FitViewHelper.java 文件源码

/**
 * 计算预览区域大小
 *
 * @param measureWidth
 * @param measureHeight
 * @return 是否应该调用requestLayout刷新视图
 */
protected boolean calculatePreviewSize(int measureWidth, int measureHeight) {
    Point size;
    if (mScaleType == ScaleType.FIT_CENTER) {
        size = fitCenter(measureWidth, measureHeight);
    } else if (mScaleType == ScaleType.FIT_WIDTH) {
        size = fitWidth(measureWidth, measureHeight);
    } else if (mScaleType == ScaleType.FIT_HEIGHT) {
        size = fitHeight(measureWidth, measureHeight);
    } else {
        size = centerCrop(measureWidth, measureHeight);
    }

    boolean change = size.x != mPreviewWidth || size.y != mPreviewHeight;
    mPreviewWidth = size.x;
    mPreviewHeight = size.y;
    return change;
}