creating a drawable from sd card to set as a background in android
I am trying to use an image from the sd card and set it as the background for a relativelayout. I have tried other solutions that i have found here and elsewhere but they havent seemed to work for me. here is my code. I have commented out other ways that i have tried and didnt work. the only thing that worked for me was using setBackgroudnResource and using a resource from the app, but this was just to test to make sure mRoot was set up correctly. when I have tried all the other ways, it just doesn't set anything. Anyone know what I am doing wrong, or if there is a better way to do this?
//one way i tired...
//String extDir = Environment.getExternalStorageDirectory().toString();
//Drawable d = Drawable.createFromPath(extDir + "/pic.png");
//mRoot.setBackgroundDrawable(d);
//another way tried..
//Drawable d = Drawable.createFromPath("/sdcard/pic.png");
//mRoot.setBackgroundDrawable(d);
//last way i tried...
mRoot.setBackgroundDrawable(Drawable.createFromPath(new File(Environment.getExternalStorageDirectory(), "pic.png").ge开发者_StackOverflowtAbsolutePath()));
//worked, only to verify mRoot was setup correctly and it could be changed
//mRoot.setBackgroundResource(R.drawable.bkg);
You do not load a drawable from SD card but a bitmap. Here is a method to load it with the reduced sampling (quality) so the program will not complain if the image is too large. Then I guess you need to process this bitmap i.e. crop it and resize for the background.
// Read bitmap from Uri
public Bitmap readBitmap(Uri selectedImage) {
Bitmap bm = null;
BitmapFactory.Options options = new BitmapFactory.Options();
options.inSampleSize = 2; //reduce quality
AssetFileDescriptor fileDescriptor =null;
try {
fileDescriptor = this.getContentResolver().openAssetFileDescriptor(selectedImage,"r");
} catch (FileNotFoundException e) {
e.printStackTrace();
}
finally{
try {
bm = BitmapFactory.decodeFileDescriptor(fileDescriptor.getFileDescriptor(), null, options);
fileDescriptor.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return bm;
}
The Uri here can be supplied from a gallery picker activity.
The image then can be saved into application resources and loaded into an imageView
private void saveBackground(Bitmap Background) {
String strBackgroundFilename = "background_custom.jpg";
try {
Background.compress(CompressFormat.JPEG, 80, openFileOutput(strBackgroundFilename, MODE_PRIVATE));
} catch (Exception e) {
Log.e(DEBUG_TAG, "Background compression and save failed.", e);
}
Uri imageUriToSaveCameraImageTo = Uri.fromFile(new File(BackgroundSettings.this.getFilesDir(), strBackgroundFilename));
// Load this image
Bitmap bitmapImage = BitmapFactory.decodeFile(imageUriToSaveCameraImageTo.getPath());
Drawable bgrImage = new BitmapDrawable(bitmapImage);
//show it in a view
ImageView backgroundView = (ImageView) findViewById(R.id.BackgroundImageView);
backgroundView.setImageURI(null);
backgroundView.setImageDrawable(bgrImage);
}
File file = new File( url.getAbsolutePath(), imageUrl);
if (file.exists()) {
mDrawable = Drawable.createFromPath(file.getAbsolutePath());
}
I suggest checking that the drawable is being loaded correctly. Some things to try:
- Try using a different image on the sd card
- Put pic.png in R.drawable and make sure mRoot.setBackgroundResource() does what you expect
- After loading the drawable, check d.getBounds() to make sure it is what you expect
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