Removing polling for resetting video playback

Previously a Handler would check once a second if the video has
exceed the range selector's duration. This is now changed to
use a timer. When the video is paused the timer is deleted
until the video playback is resumed.

As an additional simplification, the playback location is no longer
saved when the video is paused; instead playback always restarts
from the beginning.

Author: brarcher

app/src/main/java/protect/videotranscoder/activity/MainActivity.java

@@ -14,7 +14,6 @@
 import android.os.Build;
 import android.os.Bundle;
 import android.os.Environment;
-import android.os.Handler;
 import android.provider.DocumentsContract;
 import android.provider.MediaStore;
 import android.support.v4.app.ActivityCompat;
@@ -39,7 +38,10 @@
 import java.util.Calendar;
 import java.util.Collections;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
+import java.util.Timer;
+import java.util.TimerTask;
 
 import protect.videotranscoder.FFmpegResponseHandler;
 import protect.videotranscoder.FFmpegUtil;
@@ -51,11 +53,10 @@ public class MainActivity extends AppCompatActivity
     private static final int REQUEST_TAKE_GALLERY_VIDEO = 100;
     private VideoView videoView;
     private CrystalRangeSeekbar rangeSeekBar;
-    private Runnable r;
+    private Timer videoTimer = null;
     private ProgressDialog progressDialog;
     private Uri selectedVideoUri;
     private static final String TAG = "VideoTranscoder";
-    private int stopPosition;
     private TextView tvLeft, tvRight;
     private String filePath;
     private int durationMs;
@@ -223,20 +224,50 @@ private void selectVideo()
         startActivityForResult(Intent.createChooser(intent, message), REQUEST_TAKE_GALLERY_VIDEO);
     }
 
+    private void stopVideoPlayback()
+    {
+        videoView.pause();
+        if(videoTimer != null)
+        {
+            videoTimer.cancel();
+            videoTimer = null;
+        }
+    }
+
+    private void startVideoPlayback()
+    {
+        stopVideoPlayback();
+
+        int startTimeSec = rangeSeekBar.getSelectedMinValue().intValue();
+        int stopTimeSec = rangeSeekBar.getSelectedMaxValue().intValue();
+        int durationSec = stopTimeSec - startTimeSec;
+
+        videoView.seekTo(startTimeSec * 1000);
+        videoView.start();
+
+        videoTimer = new Timer();
+        videoTimer.schedule(new TimerTask()
+        {
+            @Override
+            public void run()
+            {
+                startVideoPlayback();
+            }
+        }, durationSec * 1000);
+    }
+
     @Override
     protected void onPause()
     {
         super.onPause();
-        stopPosition = videoView.getCurrentPosition(); //stopPosition is an int
-        videoView.pause();
+        stopVideoPlayback();
     }
 
     @Override
     protected void onResume()
     {
         super.onResume();
-        videoView.seekTo(stopPosition);
-        videoView.start();
+        startVideoPlayback();
     }
 
     @Override
@@ -287,25 +318,12 @@ public void onPrepared(MediaPlayer mp)
                             @Override
                             public void valueChanged(Number minValue, Number maxValue)
                             {
-                                videoView.seekTo(minValue.intValue() * 1000);
                                 tvLeft.setText(getTime(minValue.intValue()));
                                 tvRight.setText(getTime(maxValue.intValue()));
-                            }
-                        });
 
-                        final Handler handler = new Handler();
-                        handler.postDelayed(r = new Runnable()
-                        {
-                            @Override
-                            public void run()
-                            {
-
-                                if (videoView.getCurrentPosition() >= rangeSeekBar.getSelectedMaxValue().intValue() * 1000)
-                                    videoView.seekTo(rangeSeekBar.getSelectedMinValue().intValue() * 1000);
-                                handler.postDelayed(r, 1000);
+                                startVideoPlayback();
                             }
-                        }, 1000);
-
+                        });
                     }
                 });
             }
@@ -369,8 +387,7 @@ public void onClick(DialogInterface dialog, int which)
                     })
                     .show();
 
-            videoView.seekTo(stopPosition);
-            videoView.start();
+            startVideoPlayback();
         }
     };
 
@@ -405,8 +422,7 @@ private void executeCutVideoCommand(int startMs, int endMs)
         FFmpegResponseHandler handler = new FFmpegResponseHandler(durationMs, progressDialog, _transcodeResultHandler);
         FFmpegUtil.call(complexCommand, handler);
 
-        stopPosition = videoView.getCurrentPosition(); //stopPosition is an int
-        videoView.pause();
+        stopVideoPlayback();
     }
 
     /**
@@ -439,8 +455,7 @@ private void executeCompressCommand()
         FFmpegResponseHandler handler = new FFmpegResponseHandler(durationMs, progressDialog, _transcodeResultHandler);
         FFmpegUtil.call(complexCommand, handler);
 
-        stopPosition = videoView.getCurrentPosition();
-        videoView.pause();
+        stopVideoPlayback();
     }
 
     /**
@@ -472,8 +487,7 @@ private void extractAudioVideo()
         FFmpegResponseHandler handler = new FFmpegResponseHandler(durationMs, progressDialog, _transcodeResultHandler);
         FFmpegUtil.call(complexCommand, handler);
 
-        stopPosition = videoView.getCurrentPosition(); //stopPosition is an int
-        videoView.pause();
+        stopVideoPlayback();
     }
 
     /**