Refactor loggers onto common base, add option to set metadata

.idea/gradle.xml

@@ -1,11 +1,10 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
+  <component name="GradleMigrationSettings" migrationVersion="1" />
   <component name="GradleSettings">
     <option name="linkedExternalProjectsSettings">
       <GradleProjectSettings>
-        <compositeConfiguration>
+        <option name="testRunner" value="PLATFORM" />
-          <compositeBuild compositeDefinitionSource="SCRIPT" />
-        </compositeConfiguration>
         <option name="distributionType" value="DEFAULT_WRAPPED" />
         <option name="externalProjectPath" value="$PROJECT_DIR$" />
         <option name="modules">
@@ -15,7 +14,6 @@
           </set>
         </option>
         <option name="resolveModulePerSourceSet" value="false" />
-        <option name="testRunner" value="PLATFORM" />
       </GradleProjectSettings>
     </option>
   </component>

.idea/modules.xml

@@ -2,7 +2,9 @@
 <project version="4">
   <component name="ProjectModuleManager">
     <modules>
+      <module fileurl="file://$PROJECT_DIR$/Forschungsstelle-SensorReadout.iml" filepath="$PROJECT_DIR$/Forschungsstelle-SensorReadout.iml" group="SensorReadout" />
       <module fileurl="file://$PROJECT_DIR$/SensorReadout.iml" filepath="$PROJECT_DIR$/SensorReadout.iml" />
+      <module fileurl="file://$PROJECT_DIR$/app/SensorReadout-app.iml" filepath="$PROJECT_DIR$/app/SensorReadout-app.iml" group="SensorReadout/app" />
       <module fileurl="file://$PROJECT_DIR$/app/app.iml" filepath="$PROJECT_DIR$/app/app.iml" />
     </modules>
   </component>

app/src/main/java/de/fhws/indoor/sensorreadout/MainActivity.java

@@ -1,7 +1,6 @@
 package de.fhws.indoor.sensorreadout;
 
 import android.Manifest;
-import android.app.Activity;
 import android.app.ActivityManager;
 import android.content.Context;
 import android.content.Intent;
@@ -11,13 +10,16 @@ import android.media.MediaPlayer;
 import android.os.Build;
 import android.os.Bundle;
 import android.os.SystemClock;
-import android.preference.PreferenceManager;
+
+import androidx.appcompat.app.AppCompatActivity;
+import androidx.preference.PreferenceManager;
 import androidx.core.app.ActivityCompat;
 //import android.support.wearable.activity.WearableActivity;
 import android.util.Log;
 import android.view.View;
 import android.widget.ArrayAdapter;
 import android.widget.Button;
+import android.widget.ProgressBar;
 import android.widget.Spinner;
 import android.widget.TableLayout;
 import android.widget.TableRow;
@@ -32,14 +34,13 @@ import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
 
+import de.fhws.indoor.sensorreadout.loggers.Logger;
+import de.fhws.indoor.sensorreadout.loggers.OrderedLogger;
 import de.fhws.indoor.sensorreadout.sensors.GpsNew;
 import de.fhws.indoor.sensorreadout.sensors.GroundTruth;
-import de.fhws.indoor.sensorreadout.sensors.Logger;
 import de.fhws.indoor.sensorreadout.sensors.PedestrianActivity;
 import de.fhws.indoor.sensorreadout.sensors.PedestrianActivityButton;
 import de.fhws.indoor.sensorreadout.sensors.PhoneSensors;
-import de.fhws.indoor.sensorreadout.sensors.OrderedLogger;
-//import de.fhws.indoor.sensorreadout.sensors.UnorderedLogger;
 import de.fhws.indoor.sensorreadout.sensors.WiFi;
 import de.fhws.indoor.sensorreadout.sensors.WiFiRTT;
 import de.fhws.indoor.sensorreadout.sensors.iBeacon;
@@ -47,7 +48,7 @@ import de.fhws.indoor.sensorreadout.sensors.mySensor;
 import de.fhws.indoor.sensorreadout.sensors.SensorType;
 
 
-public class MainActivity extends Activity {
+public class MainActivity extends AppCompatActivity {
 
     MediaPlayer mpStart;
     MediaPlayer mpStop;
@@ -57,11 +58,13 @@ public class MainActivity extends Activity {
     private final ArrayList<mySensor> sensors = new ArrayList<mySensor>();
     //private final Logger logger = new Logger(this);
     //private final LoggerRAM logger = new LoggerRAM(this);
-    private final OrderedLogger logger = new OrderedLogger(this);
+    private final Logger logger = new OrderedLogger(this);
     private Button btnStart;
+    private Button btnMetadata;
     private Button btnStop;
     private Button btnGround;
     private Button btnSettings;
+    private ProgressBar prgCacheFillStatus;
     private TableLayout activityButtonContainer;
     private HashMap<PedestrianActivity, PedestrianActivityButton> activityButtons = new HashMap<>();
     private PedestrianActivity currentPedestrianActivity = PedestrianActivity.STANDING;
@@ -72,6 +75,10 @@ public class MainActivity extends Activity {
     final private int MY_PERMISSIONS_REQUEST_READ_BT = 123;
     final private int MY_PERMISSIONS_REQUEST_READ_HEART = 321;
 
+    // file metadata
+    private String metaPerson = "";
+    private String metaComment = "";
+
     // static context access
     private static Context context;
 
@@ -115,11 +122,14 @@ public class MainActivity extends Activity {
 
         //get Buttons
         btnStart = (Button) findViewById(R.id.btnStart);
+        btnMetadata = (Button) findViewById(R.id.btnMetadata);
         btnStop = (Button) findViewById(R.id.btnStop);
         btnGround = (Button) findViewById(R.id.btnGround);
         btnSettings = (Button) findViewById(R.id.btnSettings);
         activityButtonContainer = (TableLayout) findViewById(R.id.pedestrianActivityButtonContainer);
 
+        prgCacheFillStatus = (ProgressBar) findViewById(R.id.prgCacheFillStatus);
+
         // log GroundTruth ButtonClicks using sensor number 99
         final GroundTruth grndTruth = new GroundTruth(this);
         sensors.add(grndTruth);
@@ -157,6 +167,26 @@ public class MainActivity extends Activity {
             }
         });
 
+        btnMetadata.setOnClickListener(new View.OnClickListener() {
+            @Override public void onClick(View v) {
+                if(!isInitialized){
+                    MetadataFragment metadataDialog = new MetadataFragment(metaPerson, metaComment, new MetadataFragment.ResultListener() {
+                        @Override public void onCommit(String person, String comment) {
+                            metaPerson = person;
+                            metaComment = comment;
+                            Log.d("MetadataDialog", "Person: " + person + " Comment: " + comment);
+                        }
+
+                        @Override public void onClose() {}
+                    });
+                    metadataDialog.show(getSupportFragmentManager(), "metadata");
+                }
+                else{
+                    mpFailure.start();
+                }
+            }
+        });
+
         btnStop.setOnClickListener(new View.OnClickListener() {
             @Override public void onClick(View v) {
                 if(isInitialized){
@@ -227,16 +257,16 @@ public class MainActivity extends Activity {
 
     private void start() {
         loadCounterAny = 0;
-        logger.start();
+        logger.start(new Logger.FileMetadata(metaPerson, metaComment));
         final TextView txt = (TextView) findViewById(R.id.txtFile);
-        String path =  logger.getFile().getAbsolutePath();
+        txt.setText(logger.getName());
-        txt.setText(path.substring(path.length()-17, path.length()));
         for (final mySensor s : sensors) {s.onResume(this);}
     }
 
     private void stop() {
         for (final mySensor s : sensors) {s.onPause(this);}
         logger.stop();
+        updateStatistics(SystemClock.elapsedRealtimeNanos());
         ((TextView) findViewById(R.id.txtWifi)).setText("-");
         ((TextView) findViewById(R.id.txtBeacon)).setText("-");
         ((TextView) findViewById(R.id.txtGPS)).setText("-");
@@ -277,19 +307,24 @@ public class MainActivity extends Activity {
 
         // dump buffer stats every x entries
         if (++loadCounterAny % 250 == 0) {
-            runOnUiThread(new Runnable() {
+            updateStatistics(timestamp);
-                @Override
-                public void run() {
-                    final TextView txt = (TextView) findViewById(R.id.txtBuffer);
-                    final float elapsedMinutes = (timestamp - logger.getStartTS()) / 1000.0f / 1000.0f / 1000.0f / 60.0f;
-                    final int kBPerMin = (int) (logger.getTotalSize() / 1024.0f / elapsedMinutes);
-                    txt.setText((logger.getCurrentBufferSize() / 1024) + "k, " + logger.getNumEntries() + ", " + kBPerMin + "kB/m");
-                }
-            });
         }
 
     }
 
+    private void updateStatistics(final long timestamp) {
+        runOnUiThread(new Runnable() {
+            @Override
+            public void run() {
+                final TextView txt = (TextView) findViewById(R.id.txtBuffer);
+                final float elapsedMinutes = (timestamp - logger.getStartTS()) / 1000.0f / 1000.0f / 1000.0f / 60.0f;
+                final int kBPerMin = (int) (logger.getSizeTotal() / 1024.0f / elapsedMinutes);
+                txt.setText((logger.getSizeTotal() / 1024) + "k, " + logger.getEventCnt() + ", " + kBPerMin + "kB/m");
+                prgCacheFillStatus.setProgress((int)(logger.getCacheLevel() * 1000));
+            }
+        });
+    }
+
     /** pause activity */
     protected void onPause() {
         //stop();

app/src/main/java/de/fhws/indoor/sensorreadout/MetadataFragment.java

@@ -0,0 +1,73 @@
+package de.fhws.indoor.sensorreadout;
+
+import android.app.Dialog;
+import android.content.DialogInterface;
+import android.os.Bundle;
+import android.view.LayoutInflater;
+import android.view.View;
+import android.widget.EditText;
+import android.widget.TextView;
+
+import androidx.annotation.NonNull;
+import androidx.appcompat.app.AlertDialog;
+import androidx.fragment.app.DialogFragment;
+import androidx.fragment.app.FragmentManager;
+import androidx.fragment.app.FragmentTransaction;
+
+public class MetadataFragment extends DialogFragment {
+
+    public interface ResultListener {
+
+        void onCommit(String person, String comment);
+        void onClose();
+
+    }
+
+    private String person;
+    private String comment;
+    private ResultListener resultListener;
+
+    public MetadataFragment(@NonNull String person, @NonNull String comment, @NonNull ResultListener resultListener) {
+        this.person = person;
+        this.comment = comment;
+        this.resultListener = resultListener;
+    }
+
+    @Override
+    public Dialog onCreateDialog(Bundle savedInstanceState) {
+        final AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
+        // Get the layout inflater
+        final LayoutInflater inflater = requireActivity().getLayoutInflater();
+        final View view = inflater.inflate(R.layout.dialog_metadata, null);
+
+        final EditText txtPerson = view.findViewById(R.id.txtPerson);
+        final EditText txtComment = view.findViewById(R.id.txtComment);
+
+        // Inflate and set the layout for the dialog
+        // Pass null as the parent view because its going in the dialog layout
+        builder.setView(view)
+                // Add action buttons
+                .setPositiveButton(R.string.save, new DialogInterface.OnClickListener() {
+                    @Override
+                    public void onClick(DialogInterface dialog, int id) {
+                        String person = txtPerson.getText().toString();
+                        String comment = txtComment.getText().toString();
+                        resultListener.onCommit(person, comment);
+                        resultListener.onClose();
+                    }
+                })
+                .setNegativeButton(R.string.cancel, new DialogInterface.OnClickListener() {
+                    public void onClick(DialogInterface dialog, int id) {
+                        MetadataFragment.this.getDialog().cancel();
+                        resultListener.onClose();
+                    }
+                });
+        Dialog dialog = builder.create();
+
+        // restore values
+        txtPerson.setText(person);
+        txtComment.setText(comment);
+
+        return dialog;
+    }
+}

app/src/main/java/de/fhws/indoor/sensorreadout/MyException.java

@@ -1,4 +1,4 @@
-package de.fhws.indoor.sensorreadout.sensors;
+package de.fhws.indoor.sensorreadout;
 
 import android.widget.Toast;
 
@@ -11,12 +11,12 @@ import de.fhws.indoor.sensorreadout.R;
 
 public class MyException extends RuntimeException {
 
-    MyException(final String err, final Throwable t) {
+    public MyException(final String err, final Throwable t) {
         super(err, t);
         Toast.makeText(MainActivity.getAppContext(), err, Toast.LENGTH_LONG);
     }
 
-    MyException(final String err) {
+    public MyException(final String err) {
         super(err);
         Toast.makeText(MainActivity.getAppContext(), err, Toast.LENGTH_LONG);
     }

app/src/main/java/de/fhws/indoor/sensorreadout/SettingsFragment.java

@@ -1,7 +1,6 @@
 package de.fhws.indoor.sensorreadout;
 
 import android.os.Bundle;
-import androidx.annotation.Nullable;
 import androidx.preference.PreferenceFragmentCompat;
 import androidx.preference.SwitchPreferenceCompat;
 

app/src/main/java/de/fhws/indoor/sensorreadout/loggers/DataFolder.java

@@ -1,12 +1,13 @@
-package de.fhws.indoor.sensorreadout.sensors;
+package de.fhws.indoor.sensorreadout.loggers;
 
 import android.content.Context;
-import android.os.Build;
 import android.os.Environment;
 import android.util.Log;
 
 import java.io.File;
 
+import de.fhws.indoor.sensorreadout.MyException;
+
 /**
  * Created by toni on 02/06/16.
  */

app/src/main/java/de/fhws/indoor/sensorreadout/loggers/Logger.java

@@ -0,0 +1,113 @@
+package de.fhws.indoor.sensorreadout.loggers;
+
+import android.content.Context;
+import android.os.SystemClock;
+
+import androidx.annotation.NonNull;
+
+import java.util.Date;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.atomic.AtomicLong;
+
+import de.fhws.indoor.sensorreadout.sensors.SensorType;
+
+public abstract class Logger {
+
+    public static final long BEGINNING_TS = -1;
+
+    // work data
+    private StringBuilder stringBuilder = new StringBuilder();
+    protected Context context;
+    /** timestamp of logging start. all entries are relative to this one */
+    protected long startTs = 0;
+
+    //statistics
+    private AtomicLong statEntryCnt = new AtomicLong(0);
+    private AtomicLong statSizeTotal = new AtomicLong(0);
+
+    public Logger(Context context) {
+        this.context = context;
+    }
+
+
+    public final void start(FileMetadata metadata) {
+        statEntryCnt.set(0);
+        statSizeTotal.set(0);
+        stringBuilder.setLength(0);
+        // starting timestamp
+        startTs = SystemClock.elapsedRealtimeNanos();
+        onStart();
+
+        // commit metadata
+        addCSV(SensorType.FILE_METADATA, BEGINNING_TS, metadata.toCsv());
+    }
+    public abstract void onStart();
+
+    public final void stop() {
+        onStop();
+    }
+    public abstract void onStop();
+
+    protected abstract void log(LogEntry logEntry);
+
+    public final long getStartTS() {
+        return startTs;
+    }
+    public final long getSizeTotal() { return statSizeTotal.get(); }
+    public final long getEventCnt() { return statEntryCnt.get(); }
+    public abstract long getEntriesCached();
+    public abstract float getCacheLevel();
+    public abstract String getName();
+
+    /** add a new CSV entry for the given sensor number to the internal buffer */
+    public final void addCSV(final SensorType sensorNr, final long timestamp, final String csv) {
+        final long relTS = (timestamp == Logger.BEGINNING_TS) ? 0 : (timestamp - startTs);
+        if(relTS >= 0) { // drop pre startTS logs (at the beginning, sensors sometimes deliver old values)
+            stringBuilder.append(relTS);	// relative timestamp (uses less space)
+            stringBuilder.append(';');
+            stringBuilder.append(sensorNr.id());
+            stringBuilder.append(';');
+            stringBuilder.append(csv);
+            stringBuilder.append('\n');
+            log(new LogEntry(relTS, stringBuilder.toString()));
+            statEntryCnt.incrementAndGet();
+            statSizeTotal.addAndGet(stringBuilder.length());
+            stringBuilder.setLength(0);
+        }
+    }
+
+    public static class LogEntry implements Comparable<LogEntry> {
+        public long timestamp;
+        public String csv;
+
+        public LogEntry(long timestamp, String csv) {
+            this.timestamp = timestamp;
+            this.csv = csv;
+        }
+
+        @Override
+        public int compareTo(@NonNull LogEntry another) {
+            return (timestamp < another.timestamp) ? (-1) : (+1);
+        }
+    }
+
+    public static class FileMetadata {
+        private String person;
+        private String comment;
+        private Date date;
+
+        public FileMetadata(String person, String comment) {
+            this(person, comment, new Date());
+        }
+        public FileMetadata(String person, String comment, Date date) {
+            this.person = person;
+            this.comment = comment;
+            this.date = date;
+        }
+
+        protected String toCsv() {
+            return date.toString() + ";" + person + ";" + comment;
+        }
+    }
+
+}

app/src/main/java/de/fhws/indoor/sensorreadout/loggers/LoggerRAM.java

@@ -0,0 +1,95 @@
+package de.fhws.indoor.sensorreadout.loggers;
+
+import android.content.Context;
+import android.os.SystemClock;
+import androidx.annotation.NonNull;
+import android.util.Log;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.util.ArrayList;
+import java.util.Collections;
+
+import de.fhws.indoor.sensorreadout.MyException;
+import de.fhws.indoor.sensorreadout.sensors.SensorType;
+
+/**
+ * log sensor data to RAM
+ * only flush to file when finished
+ *
+ * WARNING: overflows RAM on some smartphones, with large recordings
+ */
+public final class LoggerRAM extends Logger {
+
+    private File file;
+    private FileOutputStream fos;
+
+    private ArrayList<LogEntry> buffer = new ArrayList<>();
+
+    public LoggerRAM(Context context) {
+        super(context);
+    }
+
+    @Override
+    public void onStart() {
+        buffer.clear();
+        // open the output-file immeditaly (to get permission errors)
+        // but do NOT yet write anything to the file
+        final DataFolder folder = new DataFolder(context, "sensorOutFiles");
+        file = new File(folder.getFolder(), startTs + ".csv");
+
+        try {
+            fos = new FileOutputStream(file);
+            Log.d("logger", "will write to: " + file.toString());
+        } catch (final Exception e) {
+            throw new MyException("error while opening log-file", e);
+        }
+    }
+
+    @Override
+    public void onStop() {
+        synchronized (buffer) {
+            // sort by TS (ensure strict ordering)
+            Collections.sort(buffer);
+
+            // export each entry
+            for (LogEntry e : buffer) {
+                try {
+                    fos.write(e.csv.getBytes());
+                } catch (final Exception ex) {
+                    ex.printStackTrace();;
+                }
+            }
+            // done
+            buffer.clear();
+        }
+
+        try {
+            fos.close();
+        } catch (final Exception e) {
+            throw new MyException("error while writing log-file", e);
+        }
+    }
+
+    @Override
+    protected void log(LogEntry logEntry) {
+        synchronized (buffer) {
+            buffer.add(logEntry);
+        }
+    }
+
+    @Override
+    public long getEntriesCached() {
+        return 0;
+    }
+
+    @Override
+    public float getCacheLevel() {
+        return 0;
+    }
+
+    @Override
+    public String getName() {
+        return null;
+    }
+}

app/src/main/java/de/fhws/indoor/sensorreadout/loggers/OrderedLogger.java

@@ -1,8 +1,6 @@
-package de.fhws.indoor.sensorreadout.sensors;
+package de.fhws.indoor.sensorreadout.loggers;
 
 import android.content.Context;
-import android.os.SystemClock;
-import androidx.annotation.NonNull;
 import android.util.Log;
 
 import java.io.File;
@@ -15,15 +13,91 @@ import java.util.concurrent.ArrayBlockingQueue;
 import java.util.concurrent.BlockingQueue;
 import java.util.concurrent.atomic.AtomicInteger;
 
+import de.fhws.indoor.sensorreadout.MyException;
+
 /**
- * log sensor data to file
+ * live-reorder logged sensor data, and write to file
- * Created by Frank on 25.03.2015.
+ * Created by Markus on 07.04.2020.
- * Re-Written by Markus on 20.06.2019.
  */
-public final class OrderedLogger {
+public final class OrderedLogger extends Logger {
 
     private static final long CACHED_LINES = 10000;
 
+    // members
+    private File file;
+    private FileOutputStream fos;
+    private ReorderBuffer reorderBuffer;
+
+    public OrderedLogger(Context context) {
+        super(context);
+    }
+
+    @Override
+    public final void onStart() {
+        reorderBuffer = new ReorderBuffer(CACHED_LINES, new ReorderBufferListener() {
+            @Override
+            public void onCommit(List<LogEntry> commitSlice) {
+                for(LogEntry entry : commitSlice) {
+                    try {
+                        fos.write(entry.csv.getBytes());
+                    } catch (IOException e) {
+                        e.printStackTrace();
+                    }
+                }
+            }
+        });
+
+        // open the output-file immediately (to get permission errors)
+        // but do NOT yet write anything to the file
+        final DataFolder folder = new DataFolder(context, "sensorOutFiles");
+        file = new File(folder.getFolder(), startTs + ".csv");
+
+        try {
+            fos = new FileOutputStream(file);
+            Log.d("logger", "will write to: " + file.toString());
+        } catch (final Exception e) {
+            throw new MyException("error while opening log-file", e);
+        }
+        reorderBuffer.start();
+    }
+
+    @Override
+    public void onStop() {
+        reorderBuffer.flushAndStop();
+        try {
+            fos.close();
+        } catch (final Exception e) {
+            throw new MyException("error while wriyting log-file", e);
+        }
+    }
+
+    @Override
+    protected void log(LogEntry logEntry) {
+        synchronized (reorderBuffer) {
+            reorderBuffer.add(logEntry);
+        }
+    }
+
+    @Override
+    public long getEntriesCached() {
+        return reorderBuffer.getEntriesCached();
+    }
+
+    @Override
+    public float getCacheLevel() {
+        // 5 InputCache slots + ReorderBuffer
+        return (float)reorderBuffer.getEntriesCached() / (float)(6 * CACHED_LINES);
+    }
+
+    @Override
+    public String getName() {
+        if(file != null) {
+            return file.getName();
+        }
+        return "OrderedLogger";
+    }
+
+
     private interface ReorderBufferListener {
         void onCommit(final List<LogEntry> commitSlice);
     }
@@ -154,115 +228,4 @@ public final class OrderedLogger {
     }
 
 
-
-
-    public static final long BEGINNING_TS = -1;
-
-    private StringBuilder stringBuilder = new StringBuilder();
-    private File file;
-    private FileOutputStream fos;
-    private Context context;
-
-    private ReorderBuffer reorderBuffer;
-
-    /** timestamp of logging start. all entries are relative to this one */
-    private long startTS = 0;
-
-    public OrderedLogger(Context context) {
-        this.context = context;
-    }
-
-    /** start logging (caching a couple of entries in RAM) */
-    public final void start() {
-
-        // start empty
-        stringBuilder.setLength(0);
-        reorderBuffer = new ReorderBuffer(CACHED_LINES, new ReorderBufferListener() {
-            @Override
-            public void onCommit(List<LogEntry> commitSlice) {
-                for(LogEntry entry : commitSlice) {
-                    try {
-                        fos.write(entry.csv.getBytes());
-                    } catch (IOException e) {
-                        e.printStackTrace();
-                    }
-                }
-            }
-        });
-
-        // starting timestamp
-        startTS = SystemClock.elapsedRealtimeNanos();
-
-        // open the output-file immediately (to get permission errors)
-        // but do NOT yet write anything to the file
-        final DataFolder folder = new DataFolder(context, "sensorOutFiles");
-        file = new File(folder.getFolder(), startTS + ".csv");
-
-        try {
-            fos = new FileOutputStream(file);
-            Log.d("logger", "will write to: " + file.toString());
-        } catch (final Exception e) {
-            throw new MyException("error while opening log-file", e);
-        }
-        reorderBuffer.start();
-    }
-
-    /** stop logging and flush RAM-data to the flash-chip */
-    public final void stop() {
-        reorderBuffer.flushAndStop();
-        close();
-    }
-
-    public File getFile() {
-        return file;
-    }
-
-    public int getCurrentBufferSize() {return reorderBuffer.getEntriesCached();}
-    public int getTotalSize() {return (int)reorderBuffer.getSizeTotal();}
-
-    public int getNumEntries() {return reorderBuffer.getEntriesCached();}
-
-    /** add a new CSV entry for the given sensor number to the internal buffer */
-    public final void addCSV(final SensorType sensorNr, final long timestamp, final String csv) {
-        final long relTS = (timestamp == BEGINNING_TS) ? 0 : (timestamp - startTS);
-        if(relTS >= 0) { // drop pre startTS logs (at the beginning, sensors sometimes deliver old values)
-            stringBuilder.append(relTS);	// relative timestamp (uses less space)
-            stringBuilder.append(';');
-            stringBuilder.append(sensorNr.id());
-            stringBuilder.append(';');
-            stringBuilder.append(csv);
-            stringBuilder.append('\n');
-            LogEntry logEntry = new LogEntry(relTS, stringBuilder.toString());
-            reorderBuffer.add(logEntry);
-            stringBuilder.setLength(0);
-        }
-    }
-
-    private final void close() {
-        try {
-            fos.close();
-        } catch (final Exception e) {
-            throw new MyException("error while wriyting log-file", e);
-        }
-    }
-
-    public final long getStartTS() {
-        return startTS;
-    }
-
-
-    private static class LogEntry implements Comparable<LogEntry> {
-        public long timestamp;
-        public String csv;
-
-        public LogEntry(long timestamp, String csv) {
-            this.timestamp = timestamp;
-            this.csv = csv;
-        }
-
-        @Override
-        public int compareTo(@NonNull LogEntry another) {
-            return (timestamp < another.timestamp) ? (-1) : (+1);
-        }
-    }
 }

app/src/main/java/de/fhws/indoor/sensorreadout/loggers/UnorderedLogger.java

@@ -0,0 +1,123 @@
+package de.fhws.indoor.sensorreadout.loggers;
+
+import android.content.Context;
+import android.util.Log;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.util.concurrent.ArrayBlockingQueue;
+
+import de.fhws.indoor.sensorreadout.MyException;
+
+/**
+ * log sensor data to file
+ * Created by Frank on 25.03.2015.
+ * Re-Written by Markus on 20.06.2019.
+ * Re-Written by Markus on 07.04.2020.
+ */
+public final class UnorderedLogger extends Logger {
+
+    private static final int LINE_BUFFER_SIZE = 5000;
+
+    private File file;
+    private FileOutputStream fos;
+
+    private volatile boolean addingStopped = false; // Just to be sure
+    private ArrayBlockingQueue<LogEntry> lineBuffer = new ArrayBlockingQueue<>(LINE_BUFFER_SIZE);
+    private WriteBackWorker writeBackWorker;
+
+    public UnorderedLogger(Context context) {
+        super(context);
+    }
+
+    @Override
+    public void onStart() {
+        writeBackWorker = new WriteBackWorker();
+
+        // open the output-file immediately (to get permission errors)
+        // but do NOT yet write anything to the file
+        final DataFolder folder = new DataFolder(context, "sensorOutFiles");
+        file = new File(folder.getFolder(), startTs + ".csv");
+
+        try {
+            fos = new FileOutputStream(file);
+            Log.d("logger", "will write to: " + file.toString());
+        } catch (final Exception e) {
+            throw new MyException("error while opening log-file", e);
+        }
+        writeBackWorker.start();
+    }
+
+    @Override
+    public void onStop() {
+        addingStopped = true;
+        try {
+            writeBackWorker.join();
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+        try {
+            fos.close();
+        } catch (final Exception e) {
+            throw new MyException("error while writing log-file", e);
+        }
+    }
+
+    @Override
+    protected void log(LogEntry logEntry) {
+        lineBuffer.add(logEntry);
+    }
+
+    @Override
+    public long getEntriesCached() {
+        return lineBuffer.size();
+    }
+
+    @Override
+    public float getCacheLevel() {
+        return 1.0f - (float)lineBuffer.remainingCapacity() / (float)LINE_BUFFER_SIZE;
+    }
+
+    @Override
+    public String getName() {
+        if(file != null) {
+            return file.getName();
+        }
+        return "OrderedLogger";
+    }
+
+
+
+
+    private class WriteBackWorker extends Thread {
+
+        public WriteBackWorker() {
+            setName("WriteBackWorker");
+            setPriority(Thread.MIN_PRIORITY);
+        }
+
+        @Override
+        public void run() {
+            try {
+                while (true) {
+                    LogEntry entry = lineBuffer.poll();
+                    if (entry == null) {
+                        if (addingStopped) { // Queue empty, recording stopped. exit
+                            return;
+                        } else { // Currently no line in queue, wait 10 ms
+                            Thread.sleep(10);
+                        }
+                    } else { // print log line
+                        fos.write(entry.csv.getBytes());
+                    }
+                }
+            } catch(InterruptedException e) {
+                e.printStackTrace();
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
+        }
+    }
+
+}

app/src/main/java/de/fhws/indoor/sensorreadout/sensors/Gps.java

@@ -12,6 +12,8 @@ import android.os.Build;
 import android.os.Bundle;
 import androidx.core.content.ContextCompat;
 
+import de.fhws.indoor.sensorreadout.MyException;
+
 /**
  * Created by student on 20.03.17.
  */

app/src/main/java/de/fhws/indoor/sensorreadout/sensors/Logger.java

@@ -1,212 +0,0 @@
-package de.fhws.indoor.sensorreadout.sensors;
-
-import android.content.Context;
-import android.os.SystemClock;
-import androidx.annotation.NonNull;
-import android.util.Log;
-
-import java.io.File;
-import java.io.FileOutputStream;
-import java.io.IOException;
-import java.util.PriorityQueue;
-import java.util.concurrent.Semaphore;
-
-/**
- * log sensor data to file
- * Created by Frank on 25.03.2015.
- * Re-Written by Markus on 20.06.2019.
- */
-public final class Logger {
-
-	public static final long BEGINNING_TS = -1;
-
-	private static final int CACHED_ENTRIES = 1000;
-	private static final int FLUSH_BATCH_SIZE = 100;
-
-	private StringBuilder stringBuilder = new StringBuilder();
-	private File file;
-	private FileOutputStream fos;
-	private Context context;
-
-	private int entries = 0;
-	private int sizeTotal = 0;
-	private int currentSize = 0;
-
-	private volatile boolean addingStopped = false; // Just to be sure
-	private PriorityQueue<LogEntry> reorderBuffer = new PriorityQueue<>(2 * CACHED_ENTRIES + FLUSH_BATCH_SIZE);
-	private Semaphore flushSemaphore = new Semaphore(0);
-	private WriteBackWorker writeBackWorker;
-
-	/** timestamp of logging start. all entries are relative to this one */
-	private long startTS = 0;
-
-	public Logger(Context context) {
-		this.context = context;
-	}
-
-	/** start logging (into RAM) */
-	public final void start() {
-
-		// start empty
-		stringBuilder.setLength(0);
-		entries = 0;
-		sizeTotal = 0;
-		addingStopped = false;
-		flushSemaphore.drainPermits();
-		writeBackWorker = new WriteBackWorker();
-
-		// starting timestamp
-		startTS = SystemClock.elapsedRealtimeNanos();
-
-		// open the output-file immeditaly (to get permission errors)
-		// but do NOT yet write anything to the file
-		final DataFolder folder = new DataFolder(context, "sensorOutFiles");
-		file = new File(folder.getFolder(), startTS + ".csv");
-
-		try {
-			fos = new FileOutputStream(file);
-			Log.d("logger", "will write to: " + file.toString());
-		} catch (final Exception e) {
-			throw new MyException("error while opening log-file", e);
-		}
-		writeBackWorker.start();
-	}
-
-	/** stop logging and flush RAM-data to the flash-chip */
-	public final void stop() {
-	    debug(true);
-		synchronized (reorderBuffer) {
-			addingStopped = true;
-			// Unblock WriteBackThread for all remaining log-lines (+1)
-			// some elements in reorderBuffer could already have been released for flushing -> this might release more than necessary.
-			flushSemaphore.release(reorderBuffer.size() + 1);
-		}
-		// wait for flushing to succeed
-		try {
-			writeBackWorker.join();
-		} catch (InterruptedException e) {
-			e.printStackTrace();
-		}
-		debug(true);
-		close();
-	}
-
-	public File getFile() {
-		return file;
-	}
-
-	public int getCurrentBufferSize() {return currentSize;}
-	public int getTotalSize() {return sizeTotal;}
-
-	public int getNumEntries() {return entries;}
-
-	/** add a new CSV entry for the given sensor number to the internal buffer */
-	public final void addCSV(final SensorType sensorNr, final long timestamp, final String csv) {
-		final long relTS = (timestamp == BEGINNING_TS) ? 0 : (timestamp - startTS);
-		if(relTS >= 0) { // drop pre startTS logs (at the beginning, sensors sometimes deliver old values)
-			synchronized (reorderBuffer) {
-				if(addingStopped) {
-					// addCSV was called after calling stop();
-					return;
-				}
-
-				stringBuilder.append(relTS);	// relative timestamp (uses less space)
-				stringBuilder.append(';');
-				stringBuilder.append(sensorNr.id());
-				stringBuilder.append(';');
-				stringBuilder.append(csv);
-				stringBuilder.append('\n');
-				++entries;
-				LogEntry logEntry = new LogEntry(relTS, stringBuilder.toString());
-				sizeTotal += logEntry.csv.length();
-				currentSize += logEntry.csv.length();
-				stringBuilder.setLength(0);
-
-				// commit to reorder-buffer and start flush (if necessary)
-				reorderBuffer.add(logEntry);
-				if(flushSemaphore.availablePermits() == 0 && reorderBuffer.size() > (CACHED_ENTRIES + FLUSH_BATCH_SIZE)) {
-					// Unblock WriteBackThread and allow it to flush FLUSH_BATCH_SIZE csv-lines.
-					flushSemaphore.release(reorderBuffer.size() - CACHED_ENTRIES);
-				}
-			}
-		}
-        debug(false);
-	}
-
-	private final void close() {
-		try {
-			fos.close();
-		} catch (final Exception e) {
-			throw new MyException("error while writing log-file", e);
-		}
-	}
-
-	public final long getStartTS() {
-		return startTS;
-	}
-
-	int cnt = 0;
-	private final void debug(boolean force) {
-		if (++cnt % 1000 == 0 || force) {
-			Log.d("buffer", "size: " + reorderBuffer.size() + " lines");
-		}
-	}
-
-
-
-	private static class LogEntry implements Comparable<LogEntry> {
-		public long timestamp;
-		public String csv;
-
-		public LogEntry(long timestamp, String csv) {
-			this.timestamp = timestamp;
-			this.csv = csv;
-		}
-
-		@Override
-		public int compareTo(@NonNull LogEntry another) {
-			return (timestamp < another.timestamp) ? (-1) : (+1);
-		}
-	}
-
-	private class WriteBackWorker extends Thread {
-
-		public WriteBackWorker() {
-			setName("WriteBackWorker");
-			setPriority(Thread.MIN_PRIORITY);
-		}
-
-		@Override
-		public void run() {
-			try {
-				boolean stop = false;
-				while(!stop) {
-					flushSemaphore.acquireUninterruptibly();
-
-					LogEntry[] entriesToFlush = null;
-					synchronized (reorderBuffer) {
-                        int flushBatchSize = 1 + flushSemaphore.drainPermits(); // might contain extra-permit for stop-unblocking
-						if(flushBatchSize > reorderBuffer.size()) { // We were unblocked more than there are available lines to fush -> request to flush all & stop
-							stop = true;
-							flushBatchSize = reorderBuffer.size();
-						}
-						entriesToFlush = new LogEntry[flushBatchSize];
-
-						for(int i = 0; i < flushBatchSize; ++i) {
-							entriesToFlush[i] = reorderBuffer.poll();
-							currentSize -= entriesToFlush[i].csv.length();
-						}
-					}
-
-					for(int i = 0; i < entriesToFlush.length; ++i) {
-						fos.write(entriesToFlush[i].csv.getBytes());
-					}
-				}
-			} catch (IOException e) {
-				e.printStackTrace();
-			}
-		}
-	}
-
-
-}

app/src/main/java/de/fhws/indoor/sensorreadout/sensors/LoggerRAM.java

@@ -1,171 +0,0 @@
-package de.fhws.indoor.sensorreadout.sensors;
-
-import android.content.Context;
-import android.os.SystemClock;
-import androidx.annotation.NonNull;
-import android.util.Log;
-
-import java.io.File;
-import java.io.FileOutputStream;
-import java.util.ArrayList;
-import java.util.Collections;
-
-/**
- * log sensor data to RAM
- * only flush to file when finished
- */
-public final class LoggerRAM {
-
-    public static final long BEGINNING_TS = -1;
-
-
-    private StringBuilder stringBuilder = new StringBuilder();
-    private File file;
-    private FileOutputStream fos;
-    private Context context;
-
-    private boolean addingStopped = false;
-    private int entries = 0;
-    private int sizeTotal = 0;
-    private int currentSize = 0;
-
-    private ArrayList<LogEntry> buffer = new ArrayList<>();
-
-    /** timestamp of logging start. all entries are relative to this one */
-    private long startTS = 0;
-
-    public LoggerRAM(Context context) {
-        this.context = context;
-    }
-
-    /** start logging (into RAM) */
-    public final void start() {
-
-        // start empty
-        stringBuilder.setLength(0);
-        entries = 0;
-        sizeTotal = 0;
-        currentSize = 0;
-        buffer.clear();
-        addingStopped = false;
-
-        // starting timestamp
-        startTS = SystemClock.elapsedRealtimeNanos();
-
-        // open the output-file immeditaly (to get permission errors)
-        // but do NOT yet write anything to the file
-        final DataFolder folder = new DataFolder(context, "sensorOutFiles");
-        file = new File(folder.getFolder(), startTS + ".csv");
-
-        try {
-            fos = new FileOutputStream(file);
-            Log.d("logger", "will write to: " + file.toString());
-        } catch (final Exception e) {
-            throw new MyException("error while opening log-file", e);
-        }
-
-    }
-
-    /** stop logging and flush RAM-data to the flash-chip */
-    public final void stop() {
-
-        addingStopped = true;
-
-        synchronized (buffer) {
-
-            // sort by TS (ensure strict ordering)
-            Collections.sort(buffer);
-
-            // export each entry
-            for (LogEntry e : buffer) {
-                try {
-                    fos.write(e.csv.getBytes());
-                } catch (final Exception ex) {
-                    ex.printStackTrace();;
-                }
-            }
-
-            // done
-            buffer.clear();
-
-        }
-
-        // done
-        close();
-
-    }
-
-    public File getFile() {
-        return file;
-    }
-
-    public int getCurrentBufferSize() {return currentSize;}
-    public int getTotalSize() {return sizeTotal;}
-
-    public int getNumEntries() {return entries;}
-
-    /** add a new CSV entry for the given sensor number to the internal buffer */
-    public final void addCSV(final SensorType sensorNr, final long timestamp, final String csv) {
-
-        if (addingStopped) {return;}
-
-        final long relTS = (timestamp == BEGINNING_TS) ? 0 : (timestamp - startTS);
-        if(relTS >= 0) { // drop pre startTS logs (at the beginning, sensors sometimes deliver old values)
-
-            stringBuilder.setLength(0);
-            stringBuilder.append(relTS);	// relative timestamp (uses less space)
-            stringBuilder.append(';');
-            stringBuilder.append(sensorNr.id());
-            stringBuilder.append(';');
-            stringBuilder.append(csv);
-            stringBuilder.append('\n');
-            ++entries;
-            LogEntry logEntry = new LogEntry(relTS, stringBuilder.toString());
-            sizeTotal += logEntry.csv.length();
-            currentSize += logEntry.csv.length();
-
-            synchronized (buffer) {
-                buffer.add(logEntry);
-            }
-
-        }
-
-    }
-
-    private final void close() {
-        try {
-            fos.close();
-        } catch (final Exception e) {
-            throw new MyException("error while writing log-file", e);
-        }
-    }
-
-    public final long getStartTS() {
-        return startTS;
-    }
-
-    int cnt = 0;
-    private final void debug(boolean force) {
-        if (++cnt % 1000 == 0 || force) {
-            Log.d("buffer", "size: " + buffer.size() + " lines");
-        }
-    }
-
-
-
-    private static class LogEntry implements Comparable<LogEntry> {
-        public long timestamp;
-        public String csv;
-
-        public LogEntry(long timestamp, String csv) {
-            this.timestamp = timestamp;
-            this.csv = csv;
-        }
-
-        @Override
-        public int compareTo(@NonNull LogEntry another) {
-            return Long.compare(timestamp, another.timestamp);
-        }
-    }
-
-}

app/src/main/java/de/fhws/indoor/sensorreadout/sensors/PhoneSensors.java

@@ -9,12 +9,12 @@ import android.hardware.SensorManager;
 import android.os.Build;
 import android.util.Log;
 
-import java.io.BufferedWriter;
 import java.io.File;
 import java.io.FileOutputStream;
-import java.io.FileWriter;
 import java.io.IOException;
 
+import de.fhws.indoor.sensorreadout.loggers.DataFolder;
+
 /**
  * all available sensors
  * and what to do within one class

app/src/main/java/de/fhws/indoor/sensorreadout/sensors/SensorType.java

@@ -28,6 +28,7 @@ public enum SensorType {
     PEDESTRIAN_ACTIVITY(50),
     GROUND_TRUTH(99),
     GROUND_TRUTH_PATH(-1),
+    FILE_METADATA(-2)
 
     ;
 

app/src/main/java/de/fhws/indoor/sensorreadout/sensors/UnorderedLogger.java

@@ -1,187 +0,0 @@
-package de.fhws.indoor.sensorreadout.sensors;
-
-import android.content.Context;
-import android.os.SystemClock;
-import androidx.annotation.NonNull;
-import android.util.Log;
-
-import java.io.File;
-import java.io.FileOutputStream;
-import java.io.IOException;
-import java.util.concurrent.ArrayBlockingQueue;
-
-/**
- * log sensor data to file
- * Created by Frank on 25.03.2015.
- * Re-Written by Markus on 20.06.2019.
- */
-public final class UnorderedLogger {
-
-    public static final long BEGINNING_TS = -1;
-
-    private StringBuilder stringBuilder = new StringBuilder();
-    private File file;
-    private FileOutputStream fos;
-    private Context context;
-
-    private int entries = 0;
-    private int sizeTotal = 0;
-    private int currentSize = 0;
-
-    private volatile boolean addingStopped = false; // Just to be sure
-    private ArrayBlockingQueue<LogEntry> lineBuffer = new ArrayBlockingQueue<>(5000);
-    private WriteBackWorker writeBackWorker;
-
-    /** timestamp of logging start. all entries are relative to this one */
-    private long startTS = 0;
-
-    public UnorderedLogger(Context context) {
-        this.context = context;
-    }
-
-    /** start logging (caching a couple of entries in RAM) */
-    public final void start() {
-
-        // start empty
-        stringBuilder.setLength(0);
-        entries = 0;
-        sizeTotal = 0;
-        addingStopped = false;
-        writeBackWorker = new WriteBackWorker();
-
-        // starting timestamp
-        startTS = SystemClock.elapsedRealtimeNanos();
-
-        // open the output-file immediately (to get permission errors)
-        // but do NOT yet write anything to the file
-        final DataFolder folder = new DataFolder(context, "sensorOutFiles");
-        file = new File(folder.getFolder(), startTS + ".csv");
-
-        try {
-            fos = new FileOutputStream(file);
-            Log.d("logger", "will write to: " + file.toString());
-        } catch (final Exception e) {
-            throw new MyException("error while opening log-file", e);
-        }
-        writeBackWorker.start();
-    }
-
-    /** stop logging and flush RAM-data to the flash-chip */
-    public final void stop() {
-        debug(true);
-        addingStopped = true;
-        // wait for flushing to succeed
-        try {
-            writeBackWorker.join();
-        } catch (InterruptedException e) {
-            e.printStackTrace();
-        }
-        debug(true);
-        close();
-    }
-
-    public File getFile() {
-        return file;
-    }
-
-    public int getCurrentBufferSize() {return currentSize;}
-    public int getTotalSize() {return sizeTotal;}
-
-    public int getNumEntries() {return entries;}
-
-    /** add a new CSV entry for the given sensor number to the internal buffer */
-    public final void addCSV(final SensorType sensorNr, final long timestamp, final String csv) {
-        final long relTS = (timestamp == BEGINNING_TS) ? 0 : (timestamp - startTS);
-        if(relTS >= 0) { // drop pre startTS logs (at the beginning, sensors sometimes deliver old values)
-            if(addingStopped) {
-                // addCSV was called after calling stop();
-                return;
-            }
-
-            stringBuilder.append(relTS);	// relative timestamp (uses less space)
-            stringBuilder.append(';');
-            stringBuilder.append(sensorNr.id());
-            stringBuilder.append(';');
-            stringBuilder.append(csv);
-            stringBuilder.append('\n');
-            ++entries;
-            LogEntry logEntry = new LogEntry(relTS, stringBuilder.toString());
-            sizeTotal += logEntry.csv.length();
-            currentSize += logEntry.csv.length();
-            stringBuilder.setLength(0);
-
-
-            // Commit to line/flush buffer
-            lineBuffer.add(logEntry);
-        }
-        debug(false);
-    }
-
-    private final void close() {
-        try {
-            fos.close();
-        } catch (final Exception e) {
-            throw new MyException("error while writing log-file", e);
-        }
-    }
-
-    public final long getStartTS() {
-        return startTS;
-    }
-
-    int cnt = 0;
-    private final void debug(boolean force) {
-        if (++cnt % 1000 == 0 || force) {
-            Log.d("buffer", "size: " + lineBuffer.size() + " lines");
-        }
-    }
-
-
-
-    private static class LogEntry implements Comparable<LogEntry> {
-        public long timestamp;
-        public String csv;
-
-        public LogEntry(long timestamp, String csv) {
-            this.timestamp = timestamp;
-            this.csv = csv;
-        }
-
-        @Override
-        public int compareTo(@NonNull LogEntry another) {
-            return (timestamp < another.timestamp) ? (-1) : (+1);
-        }
-    }
-
-    private class WriteBackWorker extends Thread {
-
-        public WriteBackWorker() {
-            setName("WriteBackWorker");
-            setPriority(Thread.MIN_PRIORITY);
-        }
-
-        @Override
-        public void run() {
-            try {
-                while (true) {
-                    LogEntry entry = lineBuffer.poll();
-                    if (entry == null) {
-                        if (addingStopped) { // Queue empty, recording stopped. exit
-                            return;
-                        } else { // Currently no line in queue, wait 10 ms
-                            Thread.sleep(10);
-                        }
-                    } else { // print log line
-                        fos.write(entry.csv.getBytes());
-                    }
-                }
-            } catch(InterruptedException e) {
-                e.printStackTrace();
-            } catch (IOException e) {
-                e.printStackTrace();
-            }
-        }
-    }
-
-
-}

app/src/main/java/de/fhws/indoor/sensorreadout/sensors/WiFi.java

@@ -7,12 +7,13 @@ import android.content.Intent;
 import android.content.IntentFilter;
 import android.net.wifi.ScanResult;
 import android.net.wifi.WifiManager;
-import android.os.Debug;
 import android.util.Log;
 
 import java.lang.reflect.Method;
 import java.util.List;
 
+import de.fhws.indoor.sensorreadout.MyException;
+
 
 /**
  * Created by Frank on 25.03.2015.

app/src/main/res/layout/activity_main.xml

@@ -30,14 +30,30 @@
             android:background="@drawable/btnstopcolor"
             android:text="stop" />
 
-        <Button
+        <LinearLayout
-            android:id="@+id/btnStart"
             android:layout_width="0dp"
             android:layout_height="match_parent"
             android:layout_marginStart="10dip"
             android:layout_weight="1"
-            android:background="@drawable/btnstartcolor"
+            android:orientation="vertical"
-            android:text="start" />
+            android:weightSum="2">
+
+            <Button
+                android:id="@+id/btnStart"
+                android:layout_width="match_parent"
+                android:layout_height="0dp"
+                android:layout_weight="1"
+                android:background="@drawable/btnstartcolor"
+                android:text="start" />
+
+            <Button
+                android:id="@+id/btnMetadata"
+                android:layout_width="match_parent"
+                android:layout_height="0dp"
+                android:layout_weight="1"
+                android:background="#fff"
+                android:text="metadata" />
+        </LinearLayout>
 
         <LinearLayout
             android:id="@+id/layoutSpinner"
@@ -63,9 +79,9 @@
                 android:background="#64bbe5" />
         </LinearLayout>
     </LinearLayout>
-    
+
-    <TextView
+
-        android:id="@+id/txtFile"
+    <LinearLayout
         android:layout_width="match_parent"
         android:layout_height="0dp"
         android:layout_below="@+id/layout"
@@ -73,8 +89,29 @@
         android:layout_marginStart="20dip"
         android:layout_marginTop="10dip"
         android:layout_weight="0.25"
-        android:text="-"
+        android:orientation="horizontal"
-        android:textColor="#ffffff" />
+        android:weightSum="1">
+        <TextView
+            android:id="@+id/txtFile"
+            android:layout_width="0dp"
+            android:layout_height="match_parent"
+            android:layout_weight="0.9"
+            android:text="-"
+            android:textColor="#ffffff" />
+
+        <ProgressBar
+            android:id="@+id/prgCacheFillStatus"
+            style="@android:style/Widget.ProgressBar.Horizontal"
+            android:layout_width="0dp"
+            android:layout_height="match_parent"
+            android:layout_weight="0.1"
+            android:clickable="false"
+            android:indeterminate="false"
+            android:indeterminateOnly="false"
+            android:max="1000"
+            android:progress="0"
+            android:rotation="-90" />
+    </LinearLayout>
 
     <LinearLayout
         android:id="@+id/layoutMain"

app/src/main/res/layout/dialog_metadata.xml

@@ -0,0 +1,27 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:orientation="vertical"
+    android:layout_width="wrap_content"
+    android:layout_height="wrap_content">
+    <EditText
+        android:id="@+id/txtPerson"
+        android:inputType="text"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="16dp"
+        android:layout_marginLeft="4dp"
+        android:layout_marginRight="4dp"
+        android:layout_marginBottom="4dp"
+        android:hint="@string/personName" />
+    <EditText
+        android:id="@+id/txtComment"
+        android:inputType="text"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:layout_marginTop="4dp"
+        android:layout_marginLeft="4dp"
+        android:layout_marginRight="4dp"
+        android:layout_marginBottom="16dp"
+        android:fontFamily="sans-serif"
+        android:hint="@string/comment"/>
+</LinearLayout>

app/src/main/res/values/strings.xml

@@ -5,6 +5,12 @@
     <string name="hello_world">Hello world!</string>
     <string name="action_settings">Settings</string>
 
+    <string name="personName">Person</string>
+    <string name="comment">Comment</string>
+
+    <string name="save">Save</string>
+    <string name="cancel">Cancel</string>
+
     <string name="prefActiveSensors">Active Sensors</string>
     <string name="prefActiveSensorsSummary">Choose the sensors included in the recording</string>
     <string-array name="prefActiveSensorsEntries">