onMeasure模式

MeasureSpec.UNSPECIFIED //無限制

case MeasureSpec.EXACTLY://限制固定值/match_parent或者具體數值

MeasureSpec.AT_MOST://限制上限具體值/wrap_content

int measureWidth = getMeasuredWidth();
int measureHeight = getMeasuredHeight();
//寬
int widthSize = MeasureSpec.getSize(widthMeasureSpec);
int widthMode = MeasureSpec.getMode(widthMeasureSpec);
//高
int heightSize = MeasureSpec.getSize(heightMeasureSpec);
int heightMode = MeasureSpec.getMode(heightMeasureSpec);

switch (widthMode){
    case MeasureSpec.EXACTLY://限制固定值
        measureWidth = widthSize;
        break;
    case MeasureSpec.AT_MOST://限制上限具體值
        break;
    case MeasureSpec.UNSPECIFIED:
        break;

 

 

2.

for (int i = 0; i < getChildCount(); i++) {

    View childView = getChildAt(i);

    int childMeasureSpec;

    LayoutParams params = (LayoutParams) childView.getLayoutParams();
    int selfHeightSpecMode = MeasureSpec.getMode(heightMeasureSpec);
    int selfHeightSpecSize = MeasureSpec.getSize(heightMeasureSpec);

    switch (params.height){

        case ViewGroup.LayoutParams.WRAP_CONTENT:
            if (selfHeightSpecMode == MeasureSpec.EXACTLY || selfHeightSpecMode == MeasureSpec.AT_MOST){
                childMeasureSpec = MeasureSpec.makeMeasureSpec(selfHeightSpecSize,MeasureSpec.AT_MOST);
            }
            else {
                childMeasureSpec = MeasureSpec.makeMeasureSpec(0,MeasureSpec.UNSPECIFIED);
            }
            break;

        //父view的可用高度,怎麼計算？
        case LayoutParams.MATCH_PARENT:

            if (selfHeightSpecMode == MeasureSpec.EXACTLY || selfHeightSpecMode == MeasureSpec.AT_MOST){
                childMeasureSpec = MeasureSpec.makeMeasureSpec(selfHeightSpecSize,MeasureSpec.EXACTLY);
            }
            else {
                childMeasureSpec = MeasureSpec.makeMeasureSpec(0,MeasureSpec.UNSPECIFIED);
            }


            break;

        default:
            childMeasureSpec = MeasureSpec.makeMeasureSpec(params.height,MeasureSpec.EXACTLY);
            break;
    }

    childView.measure(widthMeasureSpec,childMeasureSpec);

    scrollHeight = scrollHeight +childView.getMeasuredHeight();
    CCLog.e("scrollHeight",scrollHeight);

    //super.onMeasure(widthMeasureSpec, scrollHeight);
    //setMeasuredDimension(getMeasuredWidth(), scrollHeight);
}