似乎所有这些答案都不适合我的Galaxy M51和Android 11。在做了一些研究之后，我发现了这个代码:

WindowMetrics windowmetrics = MainActivity.getWindowManager().getCurrentWindowMetrics();
Rect rect = windowmetrics.getBounds();
int width = rect.right;
int height =rect.bottom;

显示我的真实设备分辨率为1080x2400，其余只返回810x1800。

我建议您创建扩展函数。

/**
 * Return the width and height of the screen
 */
val Context.screenWidth: Int
  get() = resources.displayMetrics.widthPixels

val Context.screenHeight: Int
  get() = resources.displayMetrics.heightPixels

/**
 * Pixel and Dp Conversion
 */
val Float.toPx get() = this * Resources.getSystem().displayMetrics.density
val Float.toDp get() = this / Resources.getSystem().displayMetrics.density

val Int.toPx get() = (this * Resources.getSystem().displayMetrics.density).toInt()
val Int.toDp get() = (this / Resources.getSystem().displayMetrics.density).toInt()

完整的方法是使用“getRealSize”来返回真实的分辨率(包括当用户改变分辨率时)。

我注意到所有其他可用的函数，包括文档中说要用的代替this的函数，在某些情况下结果会更小。

下面是代码:

            WindowManager wm = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
            Point size = new Point();
            wm.getDefaultDisplay().getRealSize(size);
            final int width = size.x, height = size.y;

因为这可以在不同的方向上改变，这里有一个解决方案(在Kotlin中)，无论朝向如何，都能得到正确的结果:

/**
 * returns the natural orientation of the device: Configuration.ORIENTATION_LANDSCAPE or Configuration.ORIENTATION_PORTRAIT .<br></br>
 * The result should be consistent no matter the orientation of the device
 */
@JvmStatic
fun getScreenNaturalOrientation(context: Context): Int {
    //based on : http://stackoverflow.com/a/9888357/878126
    val windowManager = context.getSystemService(Context.WINDOW_SERVICE) as WindowManager
    val config = context.resources.configuration
    val rotation = windowManager.defaultDisplay.rotation
    return if ((rotation == Surface.ROTATION_0 || rotation == Surface.ROTATION_180) && config.orientation == Configuration.ORIENTATION_LANDSCAPE || (rotation == Surface.ROTATION_90 || rotation == Surface.ROTATION_270) && config.orientation == Configuration.ORIENTATION_PORTRAIT)
        Configuration.ORIENTATION_LANDSCAPE
    else
        Configuration.ORIENTATION_PORTRAIT
}

/**
 * returns the natural screen size (in pixels). The result should be consistent no matter the orientation of the device
 */
@JvmStatic
fun getScreenNaturalSize(context: Context): Point {
    val screenNaturalOrientation = getScreenNaturalOrientation(context)
    val wm = context.getSystemService(Context.WINDOW_SERVICE) as WindowManager
    val point = Point()
    wm.defaultDisplay.getRealSize(point)
    val currentOrientation = context.resources.configuration.orientation
    if (currentOrientation == screenNaturalOrientation)
        return point
    else return Point(point.y, point.x)
}

这里没有一个答案适用于Chrome OS的多显示器，或即将到来的可折叠设备。

在查找当前配置时，始终使用getResources(). getconfiguration()中当前活动的配置。不要使用来自后台活动或系统资源的配置。后台活动没有大小，系统的配置可能包含多个大小和方向冲突的窗口，因此无法提取可用的数据。

所以答案是

val config = context.getResources().getConfiguration()
val (screenWidthPx, screenHeightPx) = config.screenWidthDp.dp to config.screenHeightDp.dp

为什么不

DisplayMetrics displaymetrics = getResources().getDisplayMetrics();

然后使用

displayMetrics.widthPixels

and

displayMetrics.heightPixels

有一个非常简单的答案，没有通过上下文

public static int getScreenWidth() {
    return Resources.getSystem().getDisplayMetrics().widthPixels;
}

public static int getScreenHeight() {
    return Resources.getSystem().getDisplayMetrics().heightPixels;
}

注:如果你想要高度包括导航条，使用下面的方法

WindowManager windowManager =
        (WindowManager) BaseApplication.getApplication().getSystemService(Context.WINDOW_SERVICE);
    final Display display = windowManager.getDefaultDisplay();
    Point outPoint = new Point();
    if (Build.VERSION.SDK_INT >= 19) {
        // include navigation bar
        display.getRealSize(outPoint);
    } else {
        // exclude navigation bar
        display.getSize(outPoint);
    }
    if (outPoint.y > outPoint.x) {
        mRealSizeHeight = outPoint.y;
        mRealSizeWidth = outPoint.x;
    } else {
        mRealSizeHeight = outPoint.x;
        mRealSizeWidth = outPoint.y;
    }