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
有一种使用DisplayMetrics(API 1)来实现这一点的方法并不过时,它可以避免try/catch混乱:
// initialize the DisplayMetrics object
DisplayMetrics deviceDisplayMetrics = new DisplayMetrics();
// populate the DisplayMetrics object with the display characteristics
getWindowManager().getDefaultDisplay().getMetrics(deviceDisplayMetrics);
// get the width and height
screenWidth = deviceDisplayMetrics.widthPixels;
screenHeight = deviceDisplayMetrics.heightPixels;
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;
}
如果Display类不工作,则上面的答案将不起作用,那么您可以通过下面的方法获得宽度和高度。
private static final int WIDTH_INDEX = 0;
private static final int HEIGHT_INDEX = 1;
public static int[] getScreenSize(Context context) {
int[] widthHeight = new int[2];
widthHeight[WIDTH_INDEX] = 0;
widthHeight[HEIGHT_INDEX] = 0;
try {
WindowManager windowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
Display display = windowManager.getDefaultDisplay();
Point size = new Point();
display.getSize(size);
widthHeight[WIDTH_INDEX] = size.x;
widthHeight[HEIGHT_INDEX] = size.y;
if (!isScreenSizeRetrieved(widthHeight))
{
DisplayMetrics metrics = new DisplayMetrics();
display.getMetrics(metrics);
widthHeight[0] = metrics.widthPixels;
widthHeight[1] = metrics.heightPixels;
}
// Last defense. Use deprecated API that was introduced in lower than API 13
if (!isScreenSizeRetrieved(widthHeight)) {
widthHeight[0] = display.getWidth(); // deprecated
widthHeight[1] = display.getHeight(); // deprecated
}
} catch (Exception e) {
e.printStackTrace();
}
return widthHeight;
}
private static boolean isScreenSizeRetrieved(int[] widthHeight) {
return widthHeight[WIDTH_INDEX] != 0 && widthHeight[HEIGHT_INDEX] != 0;
}
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;
}
}
以上代码已在API级别30中弃用。现在您可以使用以下代码
val width = windowManager.currentWindowMetrics.bounds.width()
val height = windowManager.currentWindowMetrics.bounds.height()
此方法报告包括所有系统栏区域的窗口大小,而Display#getSize(Point)报告不包括导航栏和显示剪切区域的区域。Display#getSize(Point)报告的值可通过以下方式获得:
val metrics = windowManager.currentWindowMetrics
// Gets all excluding insets
val windowInsets = metrics.windowInsets
var insets: Insets = windowInsets.getInsets(WindowInsets.Type.navigationBars())
val cutout = windowInsets.displayCutout
if (cutout != null) {
val cutoutSafeInsets = Insets.of(cutout.safeInsetLeft, cutout.safeInsetTop, cutout.safeInsetRight, cutout.safeInsetBottom)
insets = Insets.max(insets, cutoutSafeInsets)
}
val insetsWidth = insets.right + insets.left
val insetsHeight = insets.top + insets.bottom
// Legacy size that Display#getSize reports
val legacySize = Size(metrics.bounds.width() - insetsWidth, metrics.bounds.height() - insetsHeight)
来源:WindowManager#getCurrentWindowMetrics()
对于正在搜索没有状态栏和操作栏的可用屏幕尺寸的用户(也感谢Swapnil的回答):
DisplayMetrics dm = getResources().getDisplayMetrics();
float screen_w = dm.widthPixels;
float screen_h = dm.heightPixels;
int resId = getResources().getIdentifier("status_bar_height", "dimen", "android");
if (resId > 0) {
screen_h -= getResources().getDimensionPixelSize(resId);
}
TypedValue typedValue = new TypedValue();
if(getTheme().resolveAttribute(android.R.attr.actionBarSize, typedValue, true)){
screen_h -= getResources().getDimensionPixelSize(typedValue.resourceId);
}