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Android 获得屏幕的宽高度
网友分享于:Jan 1, 1970 8:00:00 AM    来源: IT货架   

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在View构造函数中获得屏幕的宽高

public class GameView extends View
{ 
  public GameView(Context context)
  {
    Display d = ((Activity) context).getWindowManager().getDefaultDisplay();
    Log.v(TAG,"W + H = "+d.getWidth()+" + "+d.getHeight());
  }
}

==========================================================

DisplayMetrics定义了屏幕的一些属性,可以通过getMetrics方法得到当前屏幕的DisplayMetrics属性,代码如:

    DisplayMetrics dm = new DisplayMetrics();

    getWindowManager().getDefaultDisplay().getMetrics(dm);

    int width = dm.widthPixels;    //得到宽度

    int height = dm.heightPixels;  //得到高度


==========================================================

View中的onLayout方法传入的参数可以获得当前可用区域的宽高度:

protected void onLayout(boolean changed, int left, int top, int right,int bottom)
{

    int width = right - left;    //得到宽度

    int height = bottom - top;   //得到高度
}

获取屏幕宽高

// 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
        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
        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   
        ViewTreeObserver vto2 = imageView.getViewTreeObserver();  
        vto2.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
            @Override  
            public void onGlobalLayout() {
                imageView.getViewTreeObserver().removeGlobalOnLayoutListener(this);  
                textView.append("\n\n"+imageView.getHeight()+","+imageView.getWidth());
            }  
        });  

    <pre name="code" class="csharp">  
   此方法会加载onMeasure二次,但是回调函数只回调一次

 

WindowManager windowManager = getWindowManager();
        Display display = windowManager.getDefaultDisplay();
        screenWidth = display.getWidth();
        screenHeight = display.getHeight(); 

 

Android 获得屏幕的宽高度

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