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

需要说明的是,如果您不在“活动”中,而是在“视图”中(或在范围中具有视图类型的变量),则不需要使用WINDOW_SERVICE。那么你至少可以使用两种方法。

第一:

DisplayMetrics dm = yourView.getContext().getResources().getDisplayMetrics();

第二:

DisplayMetrics dm = new DisplayMetrics();
yourView.getDisplay().getMetrics(dm);

我们在这里调用的所有这些方法都没有被弃用。

其他回答

要获得屏幕尺寸,请使用显示度量

DisplayMetrics displayMetrics = new DisplayMetrics();
if (context != null) 
      WindowManager windowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
      Display defaultDisplay = windowManager.getDefaultDisplay();
      defaultDisplay.getRealMetrics(displayMetrics);
    }

以像素为单位获取高度和宽度

int width  =displayMetrics.widthPixels;
int height =displayMetrics.heightPixels;

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();

以下是低于/高于API 30代码的Kotlin扩展函数:

fun Activity.getScreenWidth(): Int {
    return if (Build.VERSION.SDK_INT < 30) {
        val displayMetrics = DisplayMetrics()
        windowManager.defaultDisplay.getMetrics(displayMetrics)
        displayMetrics.widthPixels
    } else {
        val metrics = windowManager.currentWindowMetrics
        val insets = metrics.windowInsets
            .getInsetsIgnoringVisibility(WindowInsets.Type.systemBars())
        metrics.bounds.width() - insets.left - insets.right
    }
}

fun Activity.getScreenHeight(): Int {
    return if (Build.VERSION.SDK_INT < 30) {
        val displayMetrics = DisplayMetrics()
        windowManager.defaultDisplay.getMetrics(displayMetrics)
        displayMetrics.heightPixels
    } else {
        val metrics = windowManager.currentWindowMetrics
        val insets = metrics.windowInsets
            .getInsetsIgnoringVisibility(WindowInsets.Type.systemBars())
        metrics.bounds.height() - insets.top - insets.bottom
    }
}

对应的Java助手方法:

public int getScreenWidth(Activity activity) {
    if (Build.VERSION.SDK_INT < 30) {
        DisplayMetrics displayMetrics = new DisplayMetrics();
        activity.getWindowManager().getDefaultDisplay().getMetrics(displayMetrics);
        return displayMetrics.widthPixels;
    } else {
        WindowMetrics metrics = activity.getWindowManager().getCurrentWindowMetrics();
        Insets insets = metrics.getWindowInsets()
                .getInsetsIgnoringVisibility(WindowInsets.Type.systemBars());
        return metrics.getBounds().width() - insets.left - insets.right;
    }
}


public int getScreenHeight(Activity activity) {
    if (Build.VERSION.SDK_INT < 30) {
        DisplayMetrics displayMetrics = new DisplayMetrics();
        activity.getWindowManager().getDefaultDisplay().getMetrics(displayMetrics);
        return displayMetrics.heightPixels;
    } else {
        WindowMetrics metrics = activity.getWindowManager().getCurrentWindowMetrics();
        Insets insets = metrics.getWindowInsets()
                .getInsetsIgnoringVisibility(WindowInsets.Type.systemBars());
        return metrics.getBounds().height() - insets.bottom - insets.top;
    }
}
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);
    }
}