Android: Uncaught exception causing fatal exception in main

Question

Hi I am writing a simple app that interacts with androids camera API directly, I'm using this tutorial http://www.tutorialspoint.com/android/android_camera.htm

Could anyone show me where I am going wrong?

The log output:

01-09 23:42:56.901: D/ATRecorder(886): com.htc.autotest.dlib.RecordEngine in loader dalvik.system.DexClassLoader@40528bb8
01-09 23:42:57.161: D/AndroidRuntime(886): Shutting down VM
01-09 23:42:57.161: W/dalvikvm(886): threadid=1: thread exiting with uncaught exception (group=0x400205a0)
01-09 23:42:57.171: E/AndroidRuntime(886): FATAL EXCEPTION: main
01-09 23:42:57.171: E/AndroidRuntime(886): java.lang.RuntimeException: startPreview failed
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.hardware.Camera.startPreview(Native Method)
01-09 23:42:57.171: E/AndroidRuntime(886):  at com.example.camera1.ShowCamera.surfaceCreated(ShowCamera.java:30)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.SurfaceView.updateWindow(SurfaceView.java:551)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.SurfaceView.dispatchDraw(SurfaceView.java:348)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.ViewGroup.drawChild(ViewGroup.java:1730)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1459)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.ViewGroup.drawChild(ViewGroup.java:1730)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1459)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.ViewGroup.drawChild(ViewGroup.java:1730)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1459)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.ViewGroup.drawChild(ViewGroup.java:1730)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1459)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.View.draw(View.java:6973)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.widget.FrameLayout.draw(FrameLayout.java:357)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.ViewGroup.drawChild(ViewGroup.java:1732)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1459)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.ViewGroup.drawChild(ViewGroup.java:1730)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.ViewGroup.dispatchDraw(ViewGroup.java:1459)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.View.draw(View.java:6973)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.widget.FrameLayout.draw(FrameLayout.java:357)
01-09 23:42:57.171: E/AndroidRuntime(886):  at com.android.internal.policy.impl.PhoneWindow$DecorView.draw(PhoneWindow.java:1997)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.ViewRoot.draw(ViewRoot.java:1600)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.ViewRoot.performTraversals(ViewRoot.java:1321)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.view.ViewRoot.handleMessage(ViewRoot.java:1957)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.os.Handler.dispatchMessage(Handler.java:99)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.os.Looper.loop(Looper.java:150)
01-09 23:42:57.171: E/AndroidRuntime(886):  at android.app.ActivityThread.main(ActivityThread.java:4277)
01-09 23:42:57.171: E/AndroidRuntime(886):  at java.lang.reflect.Method.invokeNative(Native Method)
01-09 23:42:57.171: E/AndroidRuntime(886):  at java.lang.reflect.Method.invoke(Method.java:507)
01-09 23:42:57.171: E/AndroidRuntime(886):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
01-09 23:42:57.171: E/AndroidRuntime(886):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
01-09 23:42:57.171: E/AndroidRuntime(886):  at dalvik.system.NativeStart.main(Native Method)

I've followed it perfectly but I still get and uncaught exception in log-cat when I try to run it, here is the code in MainActivity:

package com.example.camera1;

import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.hardware.Camera;
import android.hardware.Camera.PictureCallback;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.FrameLayout;
import android.widget.ImageView;
import android.widget.Toast;

public class MainActivity extends Activity {

       private Camera cameraObject;
       private ShowCamera showCamera;
       private ImageView pic;
       public static Camera isCameraAvailiable(){
          Camera object = null;
          try {
             object = Camera.open(); 
          }
          catch (Exception e){
          }
          return object; 
       }

       private PictureCallback capturedIt = new PictureCallback() {

          @Override
          public void onPictureTaken(byte[] data, Camera camera) {

          Bitmap bitmap = BitmapFactory.decodeByteArray(data , 0, data .length);
          if(bitmap==null){
             Toast.makeText(getApplicationContext(), "not taken", Toast.LENGTH_SHORT).show();
          }
          else
          {
             Toast.makeText(getApplicationContext(), "taken", Toast.LENGTH_SHORT).show();       
          }
          cameraObject.release();
       }
    };

       @Override
       protected void onCreate(Bundle savedInstanceState) {

          super.onCreate(savedInstanceState);
          setContentView(R.layout.activity_main);

          pic = (ImageView)findViewById(R.id.imageView1);
          cameraObject = isCameraAvailiable();

          showCamera = new ShowCamera(this, cameraObject);
          FrameLayout preview = (FrameLayout) findViewById(R.id.camera_preview);
          preview.addView(showCamera);
       }
       public void snapIt(View view){
          cameraObject.takePicture(null, null, capturedIt);
       }

       @Override
       public boolean onCreateOptionsMenu(Menu menu) {
          getMenuInflater().inflate(R.menu.main, menu);
          return true;
       }
    }

Here is the ShowCamera class:

package com.example.camera1;

import java.io.IOException;

import android.content.Context;
import android.hardware.Camera;
import android.view.SurfaceHolder;
import android.view.SurfaceView;

public class ShowCamera extends SurfaceView implements SurfaceHolder.Callback {

   private SurfaceHolder holdMe;
   private Camera theCamera;

   public ShowCamera(Context context,Camera camera) {
      super(context);
      theCamera = camera;
      holdMe = getHolder();
      holdMe.addCallback(this);
   }

   @Override
   public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {
   }

   @Override
   public void surfaceCreated(SurfaceHolder holder) {
      try   {
         theCamera.setPreviewDisplay(holder);
         theCamera.startPreview(); 
      } catch (IOException e) {
      }
   }

   @Override
   public void surfaceDestroyed(SurfaceHolder arg0) {
   }

}

hi sorry about that I've posted it at the top of the question. — The_Neo, Jan 19 '14 at 22:51
Could you post the full error please? The lines you posted are not very informative. — Alexis C., Jan 19 '14 at 22:52
Try to see if this help : http://stackoverflow.com/questions/13660009/camera-startpreview-failed — Alexis C., Jan 19 '14 at 23:01

score 0 · Answer 1 · answered Jan 19 '14 at 23:12

0

Try to catch a top level Exception in the surfaceCreated method (instead of IOException) and call e.getMessage() in the exception block to get more information on the type of error.

answered Jan 19 '14 at 23:12

Heisenberg

56
4

1

This is not really an answer, just a way to get to the answer. Use a comment for that. – M. Mimpen Jan 20 '14 at 10:26
It's a good advice to catch generic Exception and not only IOException working with camera. In this specific case, this could prevent the app crash (the author will need to design a fallback, though). But there will be no additional information not printed in the attached crash log. – Alex Cohn Jan 20 '14 at 10:36
Was supposed to be a comment but I needed a reputation of 50 to do so. – Heisenberg Jan 21 '14 at 09:30

score 0 · Accepted Answer · edited May 23 '17 at 11:56

0

There may be different reasons for Camera.startPreview() to throw RuntimeException. For example, it could be by set of preview size not to one of supported preview sizes.

edited May 23 '17 at 11:56

Community

1
1

answered Jan 20 '14 at 10:32

Alex Cohn

56,089
9
113
307

Android: Uncaught exception causing fatal exception in main

2 Answers2