我创建了一些自定义元素,并希望以编程方式将它们放置在右上角(距离上边缘n个像素,距离右边缘m个像素)。因此,我需要获得屏幕宽度和屏幕高度,然后设置位置:
int px = screenWidth - m;
int py = screenHeight - n;
如何在主活动中获取screenWidth和screenHeight?
我创建了一些自定义元素,并希望以编程方式将它们放置在右上角(距离上边缘n个像素,距离右边缘m个像素)。因此,我需要获得屏幕宽度和屏幕高度,然后设置位置:
int px = screenWidth - m;
int py = screenHeight - n;
如何在主活动中获取screenWidth和screenHeight?
当前回答
如果您不想增加WindowManagers、Points或Displays的开销,可以获取XML中最顶层View项的高度和宽度属性,前提是其高度和宽度设置为match_parent。(只要您的布局占据整个屏幕,这是正确的。)
例如,如果您的XML以以下内容开头:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/entireLayout"
android:layout_width="match_parent"
android:layout_height="match_parent" >
然后findViewById(R.id.entireLayout).getWidth()将返回屏幕的宽度,findViewById(R.id.entireLayout).getHeight()将显示屏幕的高度。
其他回答
遵循以下方法:
public static int getWidthScreen(Context context) {
return getDisplayMetrics(context).widthPixels;
}
public static int getHeightScreen(Context context) {
return getDisplayMetrics(context).heightPixels;
}
private static DisplayMetrics getDisplayMetrics(Context context) {
DisplayMetrics displayMetrics = new DisplayMetrics();
WindowManager wm = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
wm.getDefaultDisplay().getMetrics(displayMetrics);
return displayMetrics;
}
创建一个类和方法,如下所示:
public MyPoint getScreenDimensionsAsPixel(Context context){
WindowManager windowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
Display display = windowManager.getDefaultDisplay();
Point point = new Point();
display.getSize(point);
return new MyPoint(point.x, point.y);
}
public class MyPoint{
private int width;
private int height;
public MyPoint(int width, int height) {
this.width = width;
this.height = height;
}
public int getWidth() {
return width;
}
public void setWidth(int width) {
this.width = width;
}
public int getHeight() {
return height;
}
public void setHeight(int height) {
this.height = height;
}
}
然后在代码中使用它们:
MyPoint myPoint = getScreenDimensionsAsPixel(MainActivity.this);
Toast.makeText(MainActivity.this, "width: " + String.valueOf(myPoint.getWidth()) + "|" +
"height: " + String.valueOf(myPoint.getHeight()), Toast.LENGTH_LONG).show();
最简单的方法:
int screenHeight = getResources().getDisplayMetrics().heightPixels;
int screenWidth = getResources().getDisplayMetrics().widthPixels;
public class AndroidScreenActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
DisplayMetrics dm = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(dm);
String str_ScreenSize = "The Android Screen is: "
+ dm.widthPixels
+ " x "
+ dm.heightPixels;
TextView mScreenSize = (TextView) findViewById(R.id.strScreenSize);
mScreenSize.setText(str_ScreenSize);
}
}
我尝试了所有可能的“解决方案”,但都失败了,我注意到Elliott Hughes的“Dalvik Explorer”应用程序在任何Android设备/操作系统版本上都始终显示正确的维度。我最后看了他的开源项目,可以在这里找到:https://code.google.com/p/enh/
以下是所有相关代码:
WindowManager w = activity.getWindowManager();
Display d = w.getDefaultDisplay();
DisplayMetrics metrics = new DisplayMetrics();
d.getMetrics(metrics);
// since SDK_INT = 1;
widthPixels = metrics.widthPixels;
heightPixels = metrics.heightPixels;
try {
// used when 17 > SDK_INT >= 14; includes window decorations (statusbar bar/menu bar)
widthPixels = (Integer) Display.class.getMethod("getRawWidth").invoke(d);
heightPixels = (Integer) Display.class.getMethod("getRawHeight").invoke(d);
} catch (Exception ignored) {
}
try {
// used when SDK_INT >= 17; includes window decorations (statusbar bar/menu bar)
Point realSize = new Point();
Display.class.getMethod("getRealSize", Point.class).invoke(d, realSize);
widthPixels = realSize.x;
heightPixels = realSize.y;
} catch (Exception ignored) {
}
EDIT:略有改进的版本(避免在不受支持的OS版本上触发异常):
WindowManager w = activity.getWindowManager();
Display d = w.getDefaultDisplay();
DisplayMetrics metrics = new DisplayMetrics();
d.getMetrics(metrics);
// since SDK_INT = 1;
widthPixels = metrics.widthPixels;
heightPixels = metrics.heightPixels;
// includes window decorations (statusbar bar/menu bar)
if (Build.VERSION.SDK_INT >= 14 && Build.VERSION.SDK_INT < 17)
try {
widthPixels = (Integer) Display.class.getMethod("getRawWidth").invoke(d);
heightPixels = (Integer) Display.class.getMethod("getRawHeight").invoke(d);
} catch (Exception ignored) {
}
// includes window decorations (statusbar bar/menu bar)
if (Build.VERSION.SDK_INT >= 17)
try {
Point realSize = new Point();
Display.class.getMethod("getRealSize", Point.class).invoke(d, realSize);
widthPixels = realSize.x;
heightPixels = realSize.y;
} catch (Exception ignored) {
}