Question

这个问题让我很沮丧。

我试图缩放我在temp文件中保存的图片（下面的代码），但是当我这样做时，我收到了这个错误：

java.lang.ArithmeticException：除以零引起：java.lang.ArithmeticException：除以零

这是我的onActivityResult :(来自https://developer.android.com/training/camera/photobasics.html的代码）这里导致错误，因为image.getWidth和getHeight返回0

   @Override
protected void onActivityResult(int requestCode, int resultCode, Intent intent) {
    super.onActivityResult(requestCode, resultCode, intent);
    if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK) {


        mCurrentPhotoPath = mCurrentPhotoPath.replace("file:", "");
        Log.i(MYTAG, "Entered setFullImageFromFilePath method");
        View inflatedView = getLayoutInflater().inflate(R.layout.edit, null);
        image = (ImageView) inflatedView.findViewById(R.id.ImageviewPreview);
        // Get the dimensions of the View
        int targetW = image.getWidth();
        int targetH = image.getHeight();

        Log.i(MYTAG,"var targetW in setFullImageFromFilePath is:"  +targetW);
        Log.i(MYTAG,"the targetH in setFullImageFromFilePath is:" + targetH);


        // Get the dimensions of the bitmap
        BitmapFactory.Options bmOptions = new BitmapFactory.Options();
        bmOptions.inJustDecodeBounds = true;

        Log.i(MYTAG, "the mCurrentPhotoPath in setFullImageFromFilePath is:" + mCurrentPhotoPath);


        BitmapFactory.decodeFile(mCurrentPhotoPath, bmOptions);
        int photoW= bmOptions.outWidth;
        int photoH = bmOptions.outHeight;

        //Determine how much to scale down the image
        int scaleFactor = Math.min(photoW/targetW, photoH/targetH);

        //Decode the image file into a Bitmap sized to fill the view
        bmOptions.inJustDecodeBounds = false;
        bmOptions.inSampleSize = scaleFactor;
        bmOptions.inPurgeable = true;

        Bitmap bitmap = BitmapFactory.decodeFile(mCurrentPhotoPath, bmOptions);
        image.setImageBitmap(bitmap) ;

            Intent intent2 = new Intent(MapsActivity.this, SendScreen.class);
            startActivity(intent2);
    }
}

但是图像视图确实有宽度和高度

 <LinearLayout
        android:id="@+id/viewA"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="0.6"
        android:background="@android:color/holo_purple"
        android:orientation="horizontal">

        <ImageView
            android:contentDescription="@string/desc"
            android:id="@+id/ImageviewPreview"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:fitsSystemWindows="true"
            android:scaleType="centerCrop"
            android:src="@drawable/splash_image"
            />
    </LinearLayout>

这里我启动相机Intent并将图片保存到https://developer.android.com/training/camera/photobasics.html的临时位置，可能是图片没有正确存储，因此宽度和高度为0

    private File createImageFile() throws IOException {
    // Create an image file name
    String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
    String imageFileName = "JPEG_" + timeStamp + "_";
    File storageDir = getExternalFilesDir(Environment.DIRECTORY_PICTURES);
    File image = File.createTempFile(
            imageFileName,  /* prefix */
            ".jpg",         /* suffix */
            storageDir      /* directory */
    );

    // Save a file: path for use with ACTION_VIEW intents
    mCurrentPhotoPath = "file:" + image.getAbsolutePath();
    return image;
}

public void launchCamera(View v) {

        if (ContextCompat.checkSelfPermission(MapsActivity.this, Manifest.permission.ACCESS_FINE_LOCATION)
                == PackageManager.PERMISSION_GRANTED) {
            Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
            // Ensure that there's a camera activity to handle the intent
            if (takePictureIntent.resolveActivity(getPackageManager()) != null) {
                // Create the File where the photo should go
                File photoFile = null;
                try {
                    photoFile = createImageFile();
                } catch (IOException ex) {
                    // Error occurred while creating the File

                }
                // Continue only if the File was successfully created
                if (photoFile != null) {
                    Uri photoURI = FileProvider.getUriForFile(this,
                            "com.example.sanchez.worldgramproject",
                            photoFile);

                    takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, photoURI);

                    startActivityForResult(takePictureIntent, REQUEST_TAKE_PHOTO);

                }
            }

Answer 1

imageview还没有高度。在调用onLayout之前它没有高度，直到将视图添加到内容视图（或它的子节点）之后才会发生这种情况，并且控件已返回到事件循环，因此它可以执行布局通行证。此时它将计算其高度。在此之前它将返回0的高度。

您需要重构代码，以便在图像视图可用之前不需要它的宽度和高度。

Answer 2

您希望缩放图像适合ImageView吗？我想你可以使用毕加索：

   @Override
protected void onActivityResult(int requestCode, int resultCode, Intent intent) {
    super.onActivityResult(requestCode, resultCode, intent);
    if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK) {
        Log.i(MYTAG, "Entered setFullImageFromFilePath method");
        View inflatedView = getLayoutInflater().inflate(R.layout.edit, null);
        image = (ImageView) inflatedView.findViewById(R.id.ImageviewPreview);
        Picasso.with(context).load(new File(mCurrentPhotoPath )).into(image);
         Intent intent2 = new Intent(MapsActivity.this, SendScreen.class);
         startActivity(intent2);
    }
}

但是，我不知道你在哪里使用inflatedView？

java.lang.ArithmeticException：在onActivityResult中除以零

2 个答案: