如何在Android中对图像应用缩放,拖动和旋转

Bitmap originalBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.image);
Matrix matrix = new Matrix();
matrix.postScale(scaleX, scaleY);
Bitmap scaledBitmap = Bitmap.createBitmap(originalBitmap, 0, 0, originalBitmap.getWidth(), originalBitmap.getHeight(), matrix, true);
imageView.setImageBitmap(scaledBitmap);

private float startX;
private float startY;
private float endX;
private float endY;

@Override
public boolean onTouchEvent(MotionEvent event) {
    switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            startX = event.getX();
            startY = event.getY();
            break;
        case MotionEvent.ACTION_MOVE:
            endX = event.getX();
            endY = event.getY();
            Matrix matrix = new Matrix();
            matrix.postTranslate(endX - startX, endY - startY);
            Bitmap movedBitmap = Bitmap.createBitmap(originalBitmap, 0, 0, originalBitmap.getWidth(), originalBitmap.getHeight(), matrix, true);
            imageView.setImageBitmap(movedBitmap);
            break;
        case MotionEvent.ACTION_UP:
            break;
    }
    return true;
}

Bitmap originalBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.image);
Matrix matrix = new Matrix();
matrix.postRotate(angle);
Bitmap rotatedBitmap = Bitmap.createBitmap(originalBitmap, 0, 0, originalBitmap.getWidth(), originalBitmap.getHeight(), matrix, true);
imageView.setImageBitmap(rotatedBitmap);