当我返回上一页时，我的应用程序崩溃了

debugcn 发表于 Dev

k.kbr

我有一个应用程序，我可以在其中打开相机并拍照并保存图库。当我点击按钮打开相机时，它的工作原理。如果我在没有拍照的情况下点击手机上的后退按钮，我的应用程序就会停止。我怎么解决这个问题？

    Button camera = (Button) findViewById(R.id.camer);
    camera.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View arg0) {
            Intent cameraIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
            startActivityForResult(cameraIntent, CAMERA_PIC_REQUEST);


        }
    });

    send.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View arg0) {

            Intent i = new Intent(Intent.ACTION_SEND);


            //Log.d("URI@!@#!#!@##!", Uri.fromFile(pic).toString() + "   " + pic.exists());
            if (pic != null) {
                i.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(pic));
            }

            i.setType("image/jpg");

            startActivity(Intent.createChooser(i, "Share you on the jobing"));
        }
    });


}

protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode == CAMERA_PIC_REQUEST) {
        thumbnail = (Bitmap) data.getExtras().get("data");
        image = (ImageView) findViewById(R.id.imageToUpload);

        image.setImageBitmap(thumbnail);


        try {
            File root = Environment.getDataDirectory();
            if (root.canWrite()) {
                pic = new File(root, "pic.jpg");
                FileOutputStream out = new FileOutputStream(pic);
                thumbnail.compress(CompressFormat.JPEG, 100, out);
                out.flush();
                out.close();
            }

        } catch (IOException e) {
            Log.e("BROKEN", "Could not write file " + e.getMessage());
        }

    }

}

引起：java.lang.NullPointerException：尝试在空对象引用上调用虚拟方法“android.os.Bundle android.content.Intent.getExtras()”

桑托什·约瑟夫

因为你data是空的

试试这个方法：

protected void onActivityResult(int requestCode, int resultCode, Intent data) {
 if(requestCode == CAMERA_PIC_REQUEST){
   if (resultCode == RESULT_OK) {
       thumbnail = (Bitmap) data.getExtras().get("data");
       image = (ImageView) findViewById(R.id.imageToUpload);

       image.setImageBitmap(thumbnail);


       try {
           File root = Environment.getDataDirectory();
             if (root.canWrite()) {
                pic = new File(root, "pic.jpg");
                FileOutputStream out = new FileOutputStream(pic);
                thumbnail.compress(CompressFormat.JPEG, 100, out);
                out.flush();
                out.close();
            }

         } catch (IOException e) {
             Log.e("BROKEN", "Could not write file " + e.getMessage());
         }

      }
   }

}

更多参考：从活动中获取结果

本文收集自互联网，转载请注明来源。

如有侵权，请联系[email protected] 删除。