int getScreenSize() {
        int screenSize = getResources().getConfiguration().screenLayout &
                Configuration.SCREENLAYOUT_SIZE_MASK;
//        String toastMsg = "Screen size is neither large, normal or small";
        Display display = ((WindowManager) getSystemService(WINDOW_SERVICE)).getDefaultDisplay();
        int orientation = display.getRotation();

        int i = 0;
        switch (screenSize) {

            case Configuration.SCREENLAYOUT_SIZE_NORMAL:
                i = 1;
//                toastMsg = "Normal screen";
                break;
            case Configuration.SCREENLAYOUT_SIZE_SMALL:
                i = 1;
//                toastMsg = "Normal screen";
                break;
            case Configuration.SCREENLAYOUT_SIZE_LARGE:
//                toastMsg = "Large screen";
                if (orientation == Surface.ROTATION_90
                        || orientation == Surface.ROTATION_270) {
                    // TODO: add logic for landscape mode here
                    i = 2;
                } else {
                    i = 1;
                }


                break;
            case Configuration.SCREENLAYOUT_SIZE_XLARGE:
                if (orientation == Surface.ROTATION_90
                        || orientation == Surface.ROTATION_270) {
                    // TODO: add logic for landscape mode here
                    i = 4;
                } else {
                    i = 3;
                }

                break;


        }
//        customeToast(toastMsg);
        return i;
    }

DisplayMetrics displayMetrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(displayMetrics);
int height = displayMetrics.heightPixels;
int width = displayMetrics.widthPixels;

在某些情况下，这可能行不通。获取getMetrics注释:

Gets display metrics that describe the size and density of this display. The size returned by this method does not necessarily represent the actual raw size (native resolution) of the display. The returned size may be adjusted to exclude certain system decor elements that are always visible. It may be scaled to provide compatibility with older applications that were originally designed for smaller displays. It can be different depending on the WindowManager to which the display belongs. If requested from non-Activity context (e.g. Application context via (WindowManager) getApplicationContext().getSystemService(Context.WINDOW_SERVICE)) metrics will report the size of the entire display based on current rotation and with subtracted system decoration areas. If requested from activity (either using getWindowManager() or (WindowManager) getSystemService(Context.WINDOW_SERVICE)) resulting metrics will correspond to current app window metrics. In this case the size can be smaller than physical size in multi-window mode.

所以，要得到真正的大小:

DisplayMetrics displayMetrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getRealMetrics(displayMetrics);
int height = displayMetrics.heightPixels;
int width = displayMetrics.widthPixels;

or:

Point point = new Point();
getWindowManager().getDefaultDisplay().getRealSize(point);
int height = point.y;
int width = point.x;

    int getScreenSize() {
        int screenSize = getResources().getConfiguration().screenLayout &
                Configuration.SCREENLAYOUT_SIZE_MASK;
//        String toastMsg = "Screen size is neither large, normal or small";
        Display display = ((WindowManager) getSystemService(WINDOW_SERVICE)).getDefaultDisplay();
        int orientation = display.getRotation();

        int i = 0;
        switch (screenSize) {

            case Configuration.SCREENLAYOUT_SIZE_NORMAL:
                i = 1;
//                toastMsg = "Normal screen";
                break;
            case Configuration.SCREENLAYOUT_SIZE_SMALL:
                i = 1;
//                toastMsg = "Normal screen";
                break;
            case Configuration.SCREENLAYOUT_SIZE_LARGE:
//                toastMsg = "Large screen";
                if (orientation == Surface.ROTATION_90
                        || orientation == Surface.ROTATION_270) {
                    // TODO: add logic for landscape mode here
                    i = 2;
                } else {
                    i = 1;
                }


                break;
            case Configuration.SCREENLAYOUT_SIZE_XLARGE:
                if (orientation == Surface.ROTATION_90
                        || orientation == Surface.ROTATION_270) {
                    // TODO: add logic for landscape mode here
                    i = 4;
                } else {
                    i = 3;
                }

                break;


        }
//        customeToast(toastMsg);
        return i;
    }

只是通过parag和SpK更新答案，使其与当前SDK的向后兼容性保持一致:

int Measuredwidth = 0;  
int Measuredheight = 0;  
Point size = new Point();
WindowManager w = getWindowManager();

if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB)    {
    w.getDefaultDisplay().getSize(size);
    Measuredwidth = size.x;
    Measuredheight = size.y; 
}else{
    Display d = w.getDefaultDisplay(); 
    Measuredwidth = d.getWidth(); 
    Measuredheight = d.getHeight(); 
}

我更新了Kotlin语言的答案!

对于Kotlin:您应该调用窗口管理器并获取指标。在那简单的方法之后。

val displayMetrics = DisplayMetrics()
windowManager.defaultDisplay.getMetrics(displayMetrics)

var width = displayMetrics.widthPixels
var height = displayMetrics.heightPixels

如何用Kotlin语言有效地独立活动地使用它?

这里，我在一般的Kotlin类中创建了一个方法。你可以在所有活动中使用它。

private val T_GET_SCREEN_WIDTH:String = "screen_width"
private val T_GET_SCREEN_HEIGHT:String = "screen_height"

private fun getDeviceSizes(activity:Activity, whichSize:String):Int{

    val displayMetrics = DisplayMetrics()
    activity.windowManager.defaultDisplay.getMetrics(displayMetrics)

    return when (whichSize){
        T_GET_SCREEN_WIDTH -> displayMetrics.widthPixels
        T_GET_SCREEN_HEIGHT -> displayMetrics.heightPixels
        else -> 0 // Error
    }
}

public class DisplayInfo {
    int screen_height=0, screen_width=0;
    WindowManager wm;
    DisplayMetrics displaymetrics;

    DisplayInfo(Context context) {
        getdisplayheightWidth(context);
    }

    void getdisplayheightWidth(Context context) {
        wm = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
        displaymetrics = new DisplayMetrics();
        wm.getDefaultDisplay().getMetrics(displaymetrics);
        screen_height = displaymetrics.heightPixels;
        screen_width = displaymetrics.widthPixels;
    }

    public int getScreen_height() {
        return screen_height;
    }

    public int getScreen_width() {
        return screen_width;
    }
}