Issue 787 inactivity timer battery check

git-svn-id: https://zxing.googlecode.com/svn/trunk@1734 59b500cc-1b3d-0410-9834-0bbf25fbcc57

android/src/com/google/zxing/client/android/CaptureActivity.java

@@ -223,6 +223,8 @@ public final class CaptureActivity extends Activity implements SurfaceHolder.Cal
     copyToClipboard = prefs.getBoolean(PreferencesActivity.KEY_COPY_TO_CLIPBOARD, true);
 
     beepManager.updatePrefs();
+    
+    inactivityTimer.onResume();
   }
 
   @Override
@@ -232,6 +234,7 @@ public final class CaptureActivity extends Activity implements SurfaceHolder.Cal
       handler.quitSynchronously();
       handler = null;
     }
+    inactivityTimer.onPause();
     CameraManager.get().closeDriver();
   }
 

android/src/com/google/zxing/client/android/InactivityTimer.java

@@ -23,9 +23,13 @@ import java.util.concurrent.ThreadFactory;
 import java.util.concurrent.TimeUnit;
 
 import android.app.Activity;
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
 
 /**
- * Finishes an activity after a period of inactivity.
+ * Finishes an activity after a period of inactivity if the device is on battery power.
  */
 final class InactivityTimer {
 
@@ -35,6 +39,7 @@ final class InactivityTimer {
       Executors.newSingleThreadScheduledExecutor(new DaemonThreadFactory());
   private final Activity activity;
   private ScheduledFuture<?> inactivityFuture = null;
+  private final PowerStatusReceiver powerStatusReceiver = new PowerStatusReceiver();
 
   InactivityTimer(Activity activity) {
     this.activity = activity;
@@ -48,6 +53,14 @@ final class InactivityTimer {
                                                 TimeUnit.SECONDS);
   }
   
+  public void onPause(){
+  	activity.unregisterReceiver(powerStatusReceiver);
+  }
+  
+  public void onResume(){
+  	activity.registerReceiver(powerStatusReceiver, new IntentFilter(Intent.ACTION_BATTERY_CHANGED));
+  }
+
   private void cancel() {
     if (inactivityFuture != null) {
       inactivityFuture.cancel(true);
@@ -68,4 +81,19 @@ final class InactivityTimer {
     }
   }
 
+  private final class PowerStatusReceiver extends BroadcastReceiver {
+  	@Override
+    public void onReceive(Context context, Intent intent){
+  		if (Intent.ACTION_BATTERY_CHANGED.equals(intent.getAction())) {
+  			// 0 indicates that we're on battery
+        // In Android 2.0+, use BatteryManager.EXTRA_PLUGGED
+        if (intent.getIntExtra("plugged", -1) == 0) {
+          InactivityTimer.this.onActivity();
+        } else {
+          InactivityTimer.this.cancel();
+        }
+  		}
+  	}
+  }
+
 }