Question

我尝试从图库中选择背景图片并将其设置为Activity背景。但问题出现在我设置RelativeLayout而不是ImageView时，它会在setImageBitmap上给出错误，这是什么原因？这是我的代码：我参考了这个教程：http://viralpatel.net/blogs/pick-image-from-galary-android-app/提前致谢！

@Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK
                && null != data) {
            Uri selectedImage = data.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 picturePath = cursor.getString(columnIndex);
            cursor.close();

            ImageView imageView = (ImageView) findViewById(R.id.background);
            imageView.setImageBitmap(BitmapFactory.decodeFile(picturePath));

        }
    }

Answer 1

你不能在RelativeLayout上做query()。我想你要做的是setImageBitmap，它将Drawable作为参数。

Answer 2

这是因为RelativeLayout没有名为setImageBitmap的方法。参考此link，您可以使用它将其设置为相对布局：

File f = new File(getRealPathFromURI(path));  
Drawable d = Drawable.createFromPath(f.getAbsolutePath());
mRelativeLayout.setBackground(d);

private String getRealPathFromURI(Uri contentURI) {
        Cursor cursor = getContentResolver().query(contentURI, null, null, null, null);
        if (cursor == null) { // Source is Dropbox or other similar local file path
            return contentURI.getPath();
        } else { 
            cursor.moveToFirst(); 
            int idx = cursor.getColumnIndex(MediaStore.Images.ImageColumns.DATA); 
            return cursor.getString(idx); 
        }
    }

为什么我无法在这里将ImageBitmap设置为RelativeLayout？

2 个答案: