自定义视图宽度

Question

I've created a class for a custom view, and I overrode the onMeasure method like I show next. But when i call the getter for width and height, their always returns 0. Why does that happen?

@Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec){
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        int parentWidth = MeasureSpec.getSize(widthMeasureSpec);
        int parentHeight = MeasureSpec.getSize(heightMeasureSpec);
        this.setMeasuredDimension(parentWidth, parentHeight);
   }

Answer 1

getWidth（）和getHeight（）值仅在第一次完整布局传递（OnMeasure-> OnLayout）之后才可用，因此，如果您确实需要在使用getMeasuredWidth（）和getMeasuredHeight（）之间访问这些值