Android获取View宽高的几种方式

jopen 8年前

有时我们会有基于这样的需求,当Activity创建时,需要获取某个View的宽高,然后进行相应的操作,但是我们在onCreate,onStart中获取View的大小,获取到的值都是0,只是由于View的绘制工程还未完成,和在onCreate中弹出Dialog或者PopupWindow会报一个Activity not running原理类似。接下来就为大家介绍几种获取View宽高的方法
一、重写Activity中的onWindowFocusChanged,当Activity获取到焦点的时候View已经绘制完成,也能获取到View的准确宽高了。同样的Dialog和PopupWindow也可以在这里弹出,需要注意的是这个方法会调用多次,当hasFocus为true时,才可进行相应的操作

    @Override      public void onWindowFocusChanged(boolean hasFocus) {          super.onWindowFocusChanged(hasFocus);          if (hasFocus) {              System.out.println("onWindowFocusChanged width="                      + tvTest.getWidth() + " height=" + tvTest.getHeight());          }      }

二、

/**       * 会执行多次       */      private void getSize1() {            ViewTreeObserver vto = tvTest.getViewTreeObserver();          vto.addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {              @Override              public boolean onPreDraw() {                  int height = tvTest.getMeasuredHeight();                  int width = tvTest.getMeasuredWidth();                  System.out.println("height" + height);                  System.out.println("width" + width);                  return true;              }            });      }

三、

private void getSize2() {          ViewTreeObserver viewTreeObserver = tvTest.getViewTreeObserver();          viewTreeObserver                  .addOnGlobalLayoutListener(new OnGlobalLayoutListener() {                      @Override                      public void onGlobalLayout() {                          tvTest.getViewTreeObserver()                                  .removeGlobalOnLayoutListener(this);                          System.out.println("onGlobalLayout width="                                  + tvTest.getWidth() + " height="                                  + tvTest.getHeight());                      }                  });      }

四、

private void getSize3() {          tvTest.post(new Runnable() {                @Override              public void run() {                  System.out.println("postDelayed width=" + tvTest.getWidth()                          + " height=" + tvTest.getHeight());              }          });        }

来自: http://blog.csdn.net/soul_code/article/details/50474528