BitmapFactory | Android

Introduction

The Bitmap (android.graphics.Bitmap) class represents a bitmap image. You create bitmaps using the BitmapFactory (android.graphics.BitmapFactory) class. Bitmaps can be created using BitmapFactory from a resource, a file, or an InputStream.

From file

Pass path to the image to BitmapFactory.decodeFile() to load the image previously copied to the sdcard. The BitmapFactory creates a bitmap object with this image. Use the ImageView.setImageBitmap() method to update the ImageView component.

public class LoadImages extends Activity {

  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    ImageView image = (ImageView) findViewById(R.id.test_image);
    Bitmap bMap = BitmapFactory.decodeFile("/sdcard/test.png");
    image.setImageBitmap(bMap);
  }
}

From input stream

Create the input stream for BitmapFactory.decodeStream() using Java FileInputStream and BufferedInputStream.  Use BitmapFactory.decodeStream() to convert a BufferedInputStream into a bitmap object.

public class LoadImages extends Activity {

  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    ImageView image = (ImageView) findViewById(R.id.test_image);
    FileInputStream in;
    BufferedInputStream buf;
    
    try {

      in = new FileInputStream("/sdcard/test.png");
      buf = new BufferedInputStream(in);
      Bitmap bMap = BitmapFactory.decodeStream(buf);
      image.setImageBitmap(bMap);
      
      if (in != null) {
        in.close();
      }
      
      if (buf != null) {
        buf.close();
      }
      
    }catch (Exception e) {
       Log.e("Error reading file", e.toString());
    }
  }
}

From project resource

Use BitmapFactory.decodeResource(res, id) to get a bitmap from an Android resource.

public class LoadImages extends Activity { 

  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    ImageView image = (ImageView) findViewById(R.id.test_image);
    Bitmap bMap = BitmapFactory.decodeResource(getResources(), R.drawable.icon);
    image.setImageBitmap(bMap);
  }
}