Android编程获取屏幕宽高与获取控件宽高的方法

时间:2021-09-12 06:47:03

本文实例讲述了android编程获取屏幕宽高与获取控件宽高的方法。分享给大家供大家参考,具体如下:

获取屏幕宽高

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// 获取屏幕宽高(方法1)
int screenwidth = getwindowmanager().getdefaultdisplay().getwidth(); // 屏幕宽(像素,如:480px)
int screenheight = getwindowmanager().getdefaultdisplay().getheight(); // 屏幕高(像素,如:800p)
log.e(tag + " getdefaultdisplay", "screenwidth=" + screenwidth + "; screenheight=" + screenheight);
// 获取屏幕密度(方法2)
displaymetrics dm = new displaymetrics();
dm = getresources().getdisplaymetrics();
float density = dm.density; // 屏幕密度(像素比例:0.75/1.0/1.5/2.0)
int densitydpi = dm.densitydpi; // 屏幕密度(每寸像素:120/160/240/320)
float xdpi = dm.xdpi;
float ydpi = dm.ydpi;
log.e(tag + " displaymetrics", "xdpi=" + xdpi + "; ydpi=" + ydpi);
log.e(tag + " displaymetrics", "density=" + density + "; densitydpi=" + densitydpi);
screenwidth = dm.widthpixels; // 屏幕宽(像素,如:480px)
screenheight = dm.heightpixels; // 屏幕高(像素,如:800px)
log.e(tag + " displaymetrics(111)", "screenwidth=" + screenwidth + "; screenheight=" + screenheight);
// 获取屏幕密度(方法3)
dm = new displaymetrics();
getwindowmanager().getdefaultdisplay().getmetrics(dm);
density = dm.density; // 屏幕密度(像素比例:0.75/1.0/1.5/2.0)
densitydpi = dm.densitydpi; // 屏幕密度(每寸像素:120/160/240/320)
xdpi = dm.xdpi;
ydpi = dm.ydpi;
log.e(tag + " displaymetrics", "xdpi=" + xdpi + "; ydpi=" + ydpi);
log.e(tag + " displaymetrics", "density=" + density + "; densitydpi=" + densitydpi);
int screenwidthdip = dm.widthpixels; // 屏幕宽(dip,如:320dip)
int screenheightdip = dm.heightpixels; // 屏幕宽(dip,如:533dip)
log.e(tag + " displaymetrics(222)", "screenwidthdip=" + screenwidthdip + "; screenheightdip=" + screenheightdip);
screenwidth = (int)(dm.widthpixels * density + 0.5f); // 屏幕宽(px,如:480px)
screenheight = (int)(dm.heightpixels * density + 0.5f); // 屏幕高(px,如:800px)
log.e(tag + " displaymetrics(222)", "screenwidth=" + screenwidth + "; screenheight=" + screenheight);

获取控件的宽高

一般来说,我们在oncreate里面得到的控件的宽高全是0.采用下面的方法,可以得到真实的宽高

方法一:

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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);

此方法会加载onmeasure三次

方法二:

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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;
  }
});

此方法会加载onmeasure二次,但是回调函数会回调很多次

方法三:

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viewtreeobserver vto2 = imageview.getviewtreeobserver();
vto2.addongloballayoutlistener(new ongloballayoutlistener() {
  @override
  public void ongloballayout() {
    imageview.getviewtreeobserver().removeglobalonlayoutlistener(this);
    textview.append("\n\n"+imageview.getheight()+","+imageview.getwidth());
  }
});

此方法会加载onmeasure二次,但是回调函数只回调一次

希望本文所述对大家android程序设计有所帮助。