public boolean setDisplayMatrix(Matrix finalMatrix) {
        if (finalMatrix == null) {
            throw new IllegalArgumentException("Matrix cannot be null");
        }

        if (mImageView.getDrawable() == null) {
            return false;
        }

        mSuppMatrix.set(finalMatrix);
        checkAndDisplayMatrix();

        return true;
    }
The component of {@link PhotoView} which does the work allowing for zooming, scaling, panning, etc.
It is made public in case you need to subclass something other than {@link ImageView} and still
gain the functionality that {@link PhotoView} offers
main/src/main/java/com/quxianggif/common/view/photoview/PhotoViewAttacher.java