title: Camera preview screen black when activity resumes
body: <p>I've been trying to get the camera section on my app working for about a week now, and after finally fixing a bug, it has created a new one. </p>
  
  <p>When I resume the activity, the preview doesn't work and neither does the recording functions. By looking at Logcat, I found out my <code>Camera</code> object is equal to null and I can't find a away to recreate it. </p>
  
  <p>My On Create</p>
  
  <pre><code>mCamera = getCameraInstance();    
  // Create preview view and set it as the content of our activity.    
  mPreview = new CameraPreview(this, mCamera);    
  preview = (FrameLayout) findViewById(R.id.previewer);   
  preview.addView(mPreview);
  </code></pre>
  
  <p>Get Camera Instance Method</p>
  
  <pre><code>private Camera getCameraInstance() { 
  
          Camera c = null;     
          try {     
              //c = Camera.open(); // attempt to get a Camera instance    
               c = this.open(); // attempt to get a Camera instance    
          } catch (Exception e) {     
              // Camera is not available (in use or does not exist)    
          }     
          Log.i("TEST getCameraInstance", "" + c);     
          return c; // returns null if camera is unavailable          
  }
  </code></pre>
  
  <p>My On Pause</p>
  
  <pre><code>protected void onPause() {
  
          super.onPause();      
          try {     
              // release the camera immediately on pause event     
              // releaseCamera();    
              mCamera.stopPreview();      
              mCamera.setPreviewCallback(null);    
              mCamera.release();     
              mCamera = null;     
          } catch (Exception e) {       
              e.printStackTrace();    
          }    
  }
  </code></pre>
  
  <p>My on Resume</p>
  
  <pre><code>protected void onResume() {
  
          super.onResume();       
          try {       
              mCamera = Camera.open();      
              mCamera = getCameraInstance();     
              Log.i("TEST onresume", "onResume Runing");      
              Log.i("TEST onresume", "camera "  + mCamera);       
              mCamera.setPreviewCallback(null);      
              Log.i("TEST onresume", "camera "  + mCamera);      
              //mCamera = getCameraInstance();      
              Log.i("TEST onresume", "camera "  + mCamera);    
              // mCamera.setPreviewCallback(null);     
              mPreview = new CameraPreview(MainRecordScreen.this, mCamera);// set preview      
              Log.i("TEST onresume", "camera "  + mCamera);                                                                               
              preview.addView(mPreview);     
              Log.i("TEST onresume", "camera "  + mCamera);    
              mCamera.startPreview();              
          } catch (Exception e) {      
              Log.d(TAG, "Error starting camera preview: " + e.getMessage());    
          }      
          Log.i("TEST onresume", "camera "  + mCamera);    
  }
  </code></pre>
  
  <p>My LogCat</p>
  
  <pre><code>06-19 06:38:40.223: E/AndroidRuntime(16702): FATAL EXCEPTION: main
  06-19 06:38:40.223: E/AndroidRuntime(16702): java.lang.NullPointerException
  06-19 06:38:40.223: E/AndroidRuntime(16702):    at com.plcd.test.MainRecordScreen.prepareVideoRecorder(MainRecordScreen.java:198)
  06-19 06:38:40.223: E/AndroidRuntime(16702):    at com.plcd.test.MainRecordScreen.access$7(MainRecordScreen.java:193)
  06-19 06:38:40.223: E/AndroidRuntime(16702):    at com.plcd.test.MainRecordScreen$3.onClick(MainRecordScreen.java:115)
  06-19 06:38:40.223: E/AndroidRuntime(16702):    at android.view.View.performClick(View.java:3511)
  06-19 06:38:40.223: E/AndroidRuntime(16702):    at android.view.View$PerformClick.run(View.java:14105)
  06-19 06:38:40.223: E/AndroidRuntime(16702):    at android.os.Handler.handleCallback(Handler.java:605)
  06-19 06:38:40.223: E/AndroidRuntime(16702):    at android.os.Handler.dispatchMessage(Handler.java:92)
  06-19 06:38:40.223: E/AndroidRuntime(16702):    at android.os.Looper.loop(Looper.java:137)
  06-19 06:38:40.223: E/AndroidRuntime(16702):    at android.app.ActivityThread.main(ActivityThread.java:4424)
  06-19 06:38:40.223: E/AndroidRuntime(16702):    at java.lang.reflect.Method.invokeNative(Native Method)
  06-19 06:38:40.223: E/AndroidRuntime(16702):    at java.lang.reflect.Method.invoke(Method.java:511)
  06-19 06:38:40.223: E/AndroidRuntime(16702):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
  06-19 06:38:40.223: E/AndroidRuntime(16702):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
  06-19 06:38:40.223: E/AndroidRuntime(16702):    at dalvik.system.NativeStart.main(Native Method)
  </code></pre>
  
  <p><code>mCamera</code> returns null from the <code>getCameraInstance()</code> method if it helps.</p>