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
这是我用于任务的代码:
// `activity` is an instance of Activity class.
Display display = activity.getWindowManager().getDefaultDisplay();
Point screen = new Point();
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR2) {
display.getSize(screen);
} else {
screen.x = display.getWidth();
screen.y = display.getHeight();
}
看起来很干净,但要注意贬低。
其他回答
在Kotlin要简单得多。
val displayMetrics = Resources.getSystem().displayMetrics
displayMetrics.heightPixels
displayMetrics.widthPixels
如果您想要以像素为单位的显示尺寸,可以使用getSize:
Display display = getWindowManager().getDefaultDisplay();
Point size = new Point();
display.getSize(size);
int width = size.x;
int height = size.y;
如果您不在“活动”中,则可以通过WINDOW_SERVICE获取默认显示:
WindowManager wm = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
Display display = wm.getDefaultDisplay();
如果您在一个片段中,并且想要实现这一点,只需使用Activity.WindowManager(在Xamarin.Android中)或getActivity().getWindowManager()(在java中)。
在引入getSize之前(在API级别13中),您可以使用现在已弃用的getWidth和getHeight方法:
Display display = getWindowManager().getDefaultDisplay();
int width = display.getWidth(); // deprecated
int height = display.getHeight(); // deprecated
然而,对于用例,您正在描述布局中的边距/填充似乎更合适。
另一种方法是:DisplayMetrics
一种结构,描述有关显示器的一般信息,如大小、密度和字体比例。要访问DisplayMetrics成员,请初始化如下对象:
DisplayMetrics metrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
我们可以使用widthPixels获取以下信息:
“显示的绝对宽度(以像素为单位)。”
例子:
Log.d("ApplicationTagName", "Display width in px is " + metrics.widthPixels);
API等级30更新
final WindowMetrics metrics = windowManager.getCurrentWindowMetrics();
// Gets all excluding insets
final WindowInsets windowInsets = metrics.getWindowInsets();
Insets insets = windowInsets.getInsetsIgnoringVisibility(WindowInsets.Type.navigationBars()
| WindowInsets.Type.displayCutout());
int insetsWidth = insets.right + insets.left;
int insetsHeight = insets.top + insets.bottom;
// Legacy size that Display#getSize reports
final Rect bounds = metrics.getBounds();
final Size legacySize = new Size(bounds.width() - insetsWidth,
bounds.height() - insetsHeight);
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;
}
我有两个函数,一个用于发送上下文,另一个用于获取像素的高度和宽度:
public static int getWidth(Context mContext){
int width=0;
WindowManager wm = (WindowManager) mContext.getSystemService(Context.WINDOW_SERVICE);
Display display = wm.getDefaultDisplay();
if(Build.VERSION.SDK_INT>12){
Point size = new Point();
display.getSize(size);
width = size.x;
}
else{
width = display.getWidth(); // Deprecated
}
return width;
}
and
public static int getHeight(Context mContext){
int height=0;
WindowManager wm = (WindowManager) mContext.getSystemService(Context.WINDOW_SERVICE);
Display display = wm.getDefaultDisplay();
if(Build.VERSION.SDK_INT>12){
Point size = new Point();
display.getSize(size);
height = size.y;
}
else{
height = display.getHeight(); // Deprecated
}
return height;
}
一种方法是:
Display display = getWindowManager().getDefaultDisplay();
int width = display.getWidth();
int height = display.getHeight();
它已被弃用,您应该尝试以下代码。前两行代码提供DisplayMetrics对象。此对象包含高度像素、宽度像素等字段。
DisplayMetrics metrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
int height = metrics.heightPixels;
int width = metrics.widthPixels;
Api级别30更新
final WindowMetrics metrics = windowManager.getCurrentWindowMetrics();
// Gets all excluding insets
final WindowInsets windowInsets = metrics.getWindowInsets();
Insets insets = windowInsets.getInsetsIgnoringVisibility(WindowInsets.Type.navigationBars()
| WindowInsets.Type.displayCutout());
int insetsWidth = insets.right + insets.left;
int insetsHeight = insets.top + insets.bottom;
// Legacy size that Display#getSize reports
final Rect bounds = metrics.getBounds();
final Size legacySize = new Size(bounds.width() - insetsWidth,
bounds.height() - insetsHeight);