主动测量View的宽高

熟知UI显示流程的同学可能都知道，View要获取到尺寸，必须经过测量才能拿到，而测量则是UI显示流程的一个环节，所以按照成正常情况想要获取到View的尺寸，就需要至少等到View显示过程中的测量环节结束才能拿到。但是在开发过程中，可能有一些小众场景，为了显示效果，需要在View显示流程触发之前，对未固定尺寸的View根据内容获取其宽高，进而做其他显示上处理，如果有这样需求的同学，那么通过本篇你将学会如何在View显示流程触发之前获取View的宽高。

代码我已经封装为一个函数，可以拿来直接用，很简单，我就不再过多赘述。

Kotlin实现代码：

   fun viewMeasure(view:View):Size{
        var widthMeasureSpec = View.MeasureSpec.makeMeasureSpec(ViewGroup.LayoutParams.WRAP_CONTENT, View.MeasureSpec.UNSPECIFIED)
        var heightMeasureSpec = View.MeasureSpec.makeMeasureSpec(ViewGroup.LayoutParams.WRAP_CONTENT, View.MeasureSpec.UNSPECIFIED)

        // 测量View
        view.measure(widthMeasureSpec, heightMeasureSpec)

         // 获取测量后的宽和高
        var measuredWidth = view.getMeasuredWidth()
        var measuredHeight = view.getMeasuredHeight()

        // 输出宽和高
        Log.d("TextViewMeasure", "Width: $measuredWidth, Height: $measuredHeight")
        return Size(measuredWidth,measuredHeight)
    }

Java实现代码：

    public Size viewMeasure(View view){
        int widthMeasureSpec = View.MeasureSpec.makeMeasureSpec(ViewGroup.LayoutParams.WRAP_CONTENT, View.MeasureSpec.UNSPECIFIED);
        int heightMeasureSpec = View.MeasureSpec.makeMeasureSpec(ViewGroup.LayoutParams.WRAP_CONTENT, View.MeasureSpec.UNSPECIFIED);

        // 测量View
        view.measure(widthMeasureSpec, heightMeasureSpec);

        // 获取测量后的宽和高
        int measuredWidth = view.getMeasuredWidth();
        int measuredHeight = view.getMeasuredHeight();

        // 输出宽和高
        Log.d("TextViewMeasure", "Width: "+measuredWidth+", Height: "+measuredHeight);
        return new Size(measuredWidth,measuredHeight);
    }