Code example for Matrix

Methods: getValues, postTranslate, setScale

0
            return true; 
        } 
    } 
 
    void fixTrans() { 
        matrix.getValues(m);
        float transX = m[Matrix.MTRANS_X];
        float transY = m[Matrix.MTRANS_Y];
         
        float fixTransX = getFixTrans(transX, viewWidth, origWidth * saveScale);
        float fixTransY = getFixTrans(transY, viewHeight, origHeight * saveScale);
 
        if (fixTransX != 0 || fixTransY != 0)
            matrix.postTranslate(fixTransX, fixTransY);
    } 
 
    float getFixTrans(float trans, float viewSize, float contentSize) {
        float minTrans, maxTrans;
 
        if (contentSize <= viewSize) {
            minTrans = 0;
            maxTrans = viewSize - contentSize;
        } else { 
            minTrans = viewSize - contentSize;
            maxTrans = 0;
        } 
 
        if (trans < minTrans)
            return -trans + minTrans;
        if (trans > maxTrans)
            return -trans + maxTrans;
        return 0; 
    } 
     
    float getFixDragTrans(float delta, float viewSize, float contentSize) {
        if (contentSize <= viewSize) {
            return 0; 
        } 
        return delta;
    } 
 
    @Override 
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        viewWidth = MeasureSpec.getSize(widthMeasureSpec);
        viewHeight = MeasureSpec.getSize(heightMeasureSpec);
         
        // 
        // Rescales image on rotation 
        // 
        if (oldMeasuredHeight == viewWidth && oldMeasuredHeight == viewHeight
                || viewWidth == 0 || viewHeight == 0)
            return; 
        oldMeasuredHeight = viewHeight;
        oldMeasuredWidth = viewWidth;
 
        if (saveScale == 1) {
            //Fit to screen. 
            float scale;
 
            Drawable drawable = getDrawable();
            if (drawable == null || drawable.getIntrinsicWidth() == 0 || drawable.getIntrinsicHeight() == 0)
                return; 
            int bmWidth = drawable.getIntrinsicWidth();
            int bmHeight = drawable.getIntrinsicHeight();
             
            Log.d("bmSize", "bmWidth: " + bmWidth + " bmHeight : " + bmHeight);
 
            float scaleX = (float) viewWidth / (float) bmWidth;
            float scaleY = (float) viewHeight / (float) bmHeight;
            scale = Math.min(scaleX, scaleY);
            matrix.setScale(scale, scale);
 
            // Center the image 
            float redundantYSpace = (float) viewHeight - (scale * (float) bmHeight);
            float redundantXSpace = (float) viewWidth - (scale * (float) bmWidth);
            redundantYSpace /= (float) 2;
            redundantXSpace /= (float) 2;
 
            matrix.postTranslate(redundantXSpace, redundantYSpace);
 
            origWidth = viewWidth - 2 * redundantXSpace;
            origHeight = viewHeight - 2 * redundantYSpace;
            setImageMatrix(matrix);
        }