Always draw the given bitmap into the Drawable's bounds, respecting the bitmap's aspect ratio. Best use with an ImageView with scaleType set to FIT_XY

FitBitmapDrawable.java

    /**
     * Always draw the given bitmap into the Drawable's bounds, respecting
     * the bitmap's aspect ratio.
     * Best use with an ImageView with scaleType set to FIT_XY
     */
    public class FitBitmapDrawable extends BitmapDrawable {
        private final Matrix matrix = new Matrix();
        private final RectF mTempSrc = new RectF();
        private final RectF mTempDst = new RectF();
        private final float[] mScale = new float[2];
        private boolean mHaveFrame;

        public FitBitmapDrawable(Resources res, Bitmap bitmap) {
            super(res, bitmap);
        }

        @Override
        protected void onBoundsChange(final Rect bounds) {
            super.onBoundsChange(bounds);
            mTempSrc.set(0, 0, getIntrinsicWidth(), getIntrinsicHeight());
            mTempDst.set(0, 0, getBounds().width(), getBounds().height());

            mScale[0] = mTempSrc.width() / mTempDst.width();
            mScale[1] = mTempSrc.height() / mTempDst.height();

            matrix.setRectToRect(mTempSrc, mTempDst, Matrix.ScaleToFit.CENTER);
            mHaveFrame = true;
        }

        @Override
        public void draw(final Canvas canvas) {
            if (mHaveFrame) {
                int count = canvas.getSaveCount();
                canvas.save();
                canvas.concat(matrix);
                canvas.scale(mScale[0], mScale[1]);
                super.draw(canvas);
                canvas.restoreToCount(count);
            }
        }
    }