Question

我正在构建一个android。在一个活动里面我有一个图像按钮。当我点击它时，画廊打开，我可以选择一个图像。然后我将该图像设置为图像按钮的新图像。问题是图像在我的活动中看起来太大了。如何使其适合我的图像按钮？

protected void onActivityResult(int requestCode, int resultCode, Intent imageReturnedIntent) { 
    super.onActivityResult(requestCode, resultCode, imageReturnedIntent); 

    switch(requestCode) { 
    case SELECT_PHOTO:
        if(resultCode == RESULT_OK){  
            Uri selectedImage = imageReturnedIntent.getData();
            String[] filePathColumn = {MediaStore.Images.Media.DATA};

            Cursor cursor = getContentResolver().query(selectedImage, filePathColumn, null, null, null);
            cursor.moveToFirst();

            int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
            String filePath = cursor.getString(columnIndex);
            cursor.close();


            Bitmap yourSelectedImage = BitmapFactory.decodeFile(filePath);

            mImageButton.setImageBitmap(yourSelectedImage);
        }
    }
}

Answer 1

您可以使用此方法获取已调整大小的图像。这样就可以避免OutOfMemoryError

public static Bitmap decodeUri(Context c, Uri uri, final int requiredSize) 
            throws FileNotFoundException {
        BitmapFactory.Options o = new BitmapFactory.Options();
        o.inJustDecodeBounds = true;
        BitmapFactory.decodeStream(c.getContentResolver().openInputStream(uri), null, o);

        int width_tmp = o.outWidth
                , height_tmp = o.outHeight;
        int scale = 1;

        while(true) {
            if(width_tmp / 2 < requiredSize || height_tmp / 2 < requiredSize)
                break;
            width_tmp /= 2;
            height_tmp /= 2;
            scale *= 2;
        }

        BitmapFactory.Options o2 = new BitmapFactory.Options();
        o2.inSampleSize = scale;
        return BitmapFactory.decodeStream(c.getContentResolver().openInputStream(uri), null, o2);
    }

Answer 2

请参阅此LINK

使用：Bitmap.createScaledBitmap（Bitmap src，int dstWidth，int dstHeight，boolean filter）

或使用这些方法::

public Bitmap getResizedBitmap(Bitmap bm, int newHeight, int newWidth) {
    int width = bm.getWidth();
    int height = bm.getHeight();
    float scaleWidth = ((float) newWidth) / width;
    float scaleHeight = ((float) newHeight) / height;

    // create a matrix for the manipulation
    Matrix matrix = new Matrix();

    // resize the bit map
    matrix.postScale(scaleWidth, scaleHeight);

    // recreate the new Bitmap
    Bitmap resizedBitmap = Bitmap.createBitmap(bm, 0, 0, width, height, matrix, false);

    return resizedBitmap;
}

如何调整我从android中的库中选择的图像？

2 个答案: