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

我会这样包装getSize代码:

@SuppressLint("NewApi")
public static Point getScreenSize(Activity a) {
    Point size = new Point();
    Display d = a.getWindowManager().getDefaultDisplay();
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
        d.getSize(size);
    } else {
        size.x = d.getWidth();
        size.y = d.getHeight();
    }
    return size;
}

其他回答

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;
    }
}

我认为这是最简单的

private fun checkDisplayResolution() {
    val displayMetrics = DisplayMetrics().also {
        windowManager.defaultDisplay.getMetrics(it)
    }

    Log.i(TAG, "display width: ${displayMetrics.widthPixels}")
    Log.i(TAG, "display height: ${displayMetrics.heightPixels}")
    Log.i(TAG, "display width dpi: ${displayMetrics.xdpi}")
    Log.i(TAG, "display height dpi: ${displayMetrics.ydpi}")
    Log.i(TAG, "display density: ${displayMetrics.density}")
    Log.i(TAG, "display scaled density: ${displayMetrics.scaledDensity}")
}
DisplayMetrics dm = getResources().getDisplayMetrics();
float fwidth = dm.density * dm.widthPixels;
float fheight = dm.density * dm.heightPixels;

如果getSize由于您的minSDKVersion而给您带来错误,并且您不想使用不推荐的方法(getWidth&getHeight),那么getMetrics解决方案最初是由Balaji.K.于2011年发布的。Nik添加了一条注释,解释getDisplayMetrics也考虑了状态栏大小。

其他一些注释指的是乘以比例(密度),以获得尺寸的精确浮动值。在Android v2.2(API 8)和v4.0中测试,结果良好,无错误/警告。

它可能无法回答您的问题,但如果你需要一个视图的维度,但你的代码在尚未布局时(例如在onCreate()中)正在执行,你可以使用View.getViewTreeObserver().addOnGlobalLayoutListener()设置一个ViewTreeObserver.OnGlobalLayout侦听器,并将需要该视图的相关代码放入尺寸。布局布局完成后,将调用侦听器的回调。

创建Kotlin扩展函数以获取屏幕宽度和高度-

fun Context?.screenWidthInPx(): Int {
    if (this == null) return 0
    val dm = DisplayMetrics()
    val wm = this.getSystemService(Context.WINDOW_SERVICE) as WindowManager
    wm.defaultDisplay.getMetrics(dm)
    return dm.widthPixels
}
//comment
fun Context?.screenHeightInPx(): Int {
    if (this == null) return 0
    val dm = DisplayMetrics()
    val wm = this.getSystemService(Context.WINDOW_SERVICE) as WindowManager
    wm.defaultDisplay.getMetrics(dm)
    return dm.heightPixels
}