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  • 【Android】获取控件的宽和高


          有时候我们须要在Activity的时候获取控件的宽和高来做一些操作,以下介绍三种获取宽和高的方式:


    1. onWindowFocusChanged

    @Override
        public void onWindowFocusChanged(boolean hasFocus)
        {
            super.onWindowFocusChanged(hasFocus);
            if (hasFocus)
            {
                int width = image.getMeasuredWidth();
                int height = image.getMeasuredHeight();
                Toast.makeText(MainActivity.this, "width = " + width + "---height = " + height, Toast.LENGTH_SHORT).show();
            }
    
        }


    2. post方式

     @Override
        protected void onStart()
        {
            super.onStart();
    
            image.post(new Runnable()
            {
    
                @Override
                public void run()
                {
                    int width = image.getMeasuredWidth();
                    int height = image.getMeasuredHeight();
                    Toast.makeText(MainActivity.this, "onstart--width = " + width + "---height = " + height, Toast.LENGTH_SHORT).show();
                }
            });
        }


    3. ViewTreeObserver

     ViewTreeObserver observer = image.getViewTreeObserver();
            observer.addOnGlobalLayoutListener(new OnGlobalLayoutListener()
            {
    
                @Override
                public void onGlobalLayout()
                {
                    image.getViewTreeObserver().removeGlobalOnLayoutListener(this);
                    int width = image.getMeasuredWidth();
                    int height = image.getMeasuredHeight();
                    Toast.makeText(MainActivity.this, "onglobal--width = " + width + "---height = " + height, Toast.LENGTH_SHORT).show();
                }
            });

    备注:以上image是ImageView控件

    ImageView image = (ImageView)findViewById(R.id.image);

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  • 原文地址:https://www.cnblogs.com/blfbuaa/p/7181905.html
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