Android之获取屏幕和视图高和宽

在android中，画布Canvas的高宽其实是屏幕的高宽。 

1.

WindowManager windowManager = getWindowManager();

Display display = windowManager.getDefaultDisplay();

screenWidth = display.getWidth();

screenHeight = display.getHeight();


2
DisplayMetrics dm = new DisplayMetrics();

this.getWindowManager().getDefaultDisplay().getMetrics(dm);//this指当前activity

screenWidth =dm.widthPixels;

screenHeight =dm.heightPixels; 以上两种方法在屏幕未显示的时候，还是处于0的状态，即要在setContentView调用之后才有效。 

还可以在onDraw中由canvas来获得

viewWidth=this.getWidth();

viewHeight=this.getHeight();
2.重写view的onSizeChanged，该方法会在onCreate之后，onDraw之前调用 
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
viewHeight=h;
viewWidth=w;
super.onSizeChanged(w, h, oldw, oldh);
}
还有对屏幕显示的一些设置： 
requestWindowFeature(Window.FEATURE_NO_TITLE);
//设置为全屏模式getWindow().setFlags

setRequesteOrientation(ActivityInfo.SCREEN_ORIENTATION_LADSCAPE);