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How to set a bitmap from resource

This seems simple, I am trying to set a bitmap image but from the resources, I have within the application in the drawable folder.

bm = BitmapFactory.decodeResource(null, R.id.image);

Is this correct?

Assuming you are calling this in an Activity class

Bitmap bm = BitmapFactory.decodeResource(getResources(), R.drawable.image);

The first parameter, Resources, is required. It is normally obtainable in any Context (and subclasses like Activity).

Try this

This is from sdcard

ImageView image = (ImageView) findViewById(R.id.test_image);
Bitmap bMap = BitmapFactory.decodeFile("/sdcard/test2.png");
image.setImageBitmap(bMap);

This is from resources

Bitmap bMap = BitmapFactory.decodeResource(getResources(), R.drawable.icon);

If the resource is showing and is a view, you can also capture it. Like a screenshot:

View rootView = ((View) findViewById(R.id.yourView)).getRootView();
rootView.setDrawingCacheEnabled(true);
rootView.layout(0, 0, rootView.getWidth(), rootView.getHeight());
rootView.buildDrawingCache();

Bitmap bm = Bitmap.createBitmap(rootView.getDrawingCache());

rootView.setDrawingCacheEnabled(false);

This actually grabs the whole layout but you can alter as you wish.

If you have declare a bitmap object and you want to display it or store this bitmap object. but first you have to assign any image , and you may use the button click event, this code will only demonstrate that how to store the drawable image in bitmap Object.

Bitmap contact_pic = BitmapFactory.decodeResource(
                           v.getContext().getResources(),
                           R.drawable.android_logo
                     );

Now you can use this bitmap object, whether you want to store it, or to use it in google maps while drawing a pic on fixed latitude and longitude, or to use some where else

just replace this line

bm = BitmapFactory.decodeResource(null, R.id.image);

with

Bitmap bitmap = BitmapFactory.decodeResource(getResources(), R.drawable.YourImageName);

I mean to say just change null value with getResources() If you use this code in any button or Image view click event just append getApplicationContext() before getResources()..

Using this function you can get Image Bitmap. Just pass image url

 public Bitmap getBitmapFromURL(String strURL) {
      try {
        URL url = new URL(strURL);
        HttpURLConnection connection = (HttpURLConnection) url.openConnection();
        connection.setDoInput(true);
        connection.connect();
        InputStream input = connection.getInputStream();
        Bitmap myBitmap = BitmapFactory.decodeStream(input);
        return myBitmap;
      } catch (IOException e) {
        e.printStackTrace();
        return null;
      }
 }

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