android中view的宽高测量

///

一般的，view测量的方法：

@Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); final ImageView imageView = (ImageView) findViewById(R.id.imageview); int w = View.MeasureSpec.makeMeasureSpec(0,View.MeasureSpec.UNSPECIFIED); int h = View.MeasureSpec.makeMeasureSpec(0,View.MeasureSpec.UNSPECIFIED); imageView.measure(w, h); int height =imageView.getMeasuredHeight(); int width =imageView.getMeasuredWidth(); textView.append("\n"+height+","+width); System.out.println("执行完毕.."+System.currentTimeMillis()); } //------------------------------------------------方法一 int w = View.MeasureSpec.makeMeasureSpec(0,View.MeasureSpec.UNSPECIFIED); int h = View.MeasureSpec.makeMeasureSpec(0,View.MeasureSpec.UNSPECIFIED); imageView.measure(w, h); int height =imageView.getMeasuredHeight(); int width =imageView.getMeasuredWidth(); textView.append("\n"+height+","+width); //-----------------------------------------------方法二 ViewTreeObserver vto = imageView.getViewTreeObserver(); vto.addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() { public boolean onPreDraw() { int height = imageView.getMeasuredHeight(); int width = imageView.getMeasuredWidth(); textView.append("\n"+height+","+width); return true; } }); //-----------------------------------------------方法三 ViewTreeObserver vto2 = imageView.getViewTreeObserver(); vto2.addOnGlobalLayoutListener(new OnGlobalLayoutListener() { @Override public void onGlobalLayout() { imageView.getViewTreeObserver().removeGlobalOnLayoutListener(this); textView.append("\n\n"+imageView.getHeight()+","+imageView.getWidth()); } });

最近由于要做自定义view，需要测量view宽高，发现一个不错的api：

View.MeasureSpec.makeMeasureSpec(int,int)

参数1是一个数值，基于该数值计算

参数2是一个mode，指测量的方式，mode如下：

它有三种模式：
①、UNSPECIFIED(未指定)，父元素部队自元素施加任何束缚，子元素可以得到任意想要的大小；
②、EXACTLY(完全)，父元素决定自元素的确切大小，子元素将被限定在给定的边界里而忽略它本身大小；
③、AT_MOST(至多)，子元素至多达到指定大小的值。

具体使用如下:

int w = View.MeasureSpec.makeMeasureSpec(SCREEN_W,View.MeasureSpec.AT_MOST); int h = View.MeasureSpec.makeMeasureSpec(SCREEN_H/2,View.MeasureSpec.AT_MOST); view.measure(w, h);LogUtil.showlog("w:" + w + ",h:" + h);

intw=View.MeasureSpec.makeMeasureSpec(0,View.MeasureSpec.UNSPECIFIED);
inth=View.MeasureSpec.makeMeasureSpec(0,View.MeasureSpec.UNSPECIFIED);
textView.measure(w,h);

///

参考：

http://blog.sina.com.cn/s/blog_4172d3d60101h15p.html

http://blog.csdn.net/listening_music/article/details/7210146

http://www.tuicool.com/articles/jiuqEr

更多相关文章

随机推荐