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
这里是Kotlin实现中对上面一些答案的简单改编。它需要清单中如上所述的windowsSoftInput=“adjustResize”:
class KeyboardWatcher(private val layoutRooView: View) {
companion object {
private const val MIN_KEYBOARD_HEIGHT = 200f
}
private val displayMetrics: DisplayMetrics = layoutRooView.resources.displayMetrics
private var stateVisible = false
var observer: ((Boolean) -> Unit)? = null
init {
layoutRooView.viewTreeObserver.addOnGlobalLayoutListener {
val heightDiff = layoutRooView.rootView.height - layoutRooView.height
if (!stateVisible && heightDiff > dpToPx(MIN_KEYBOARD_HEIGHT)) {
stateVisible = true
observer?.invoke(stateVisible)
} else if(stateVisible) {
stateVisible = false
observer?.invoke(stateVisible)
}
}
}
private fun dpToPx(valueInDp: Float): Float {
return TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, valueInDp, displayMetrics)
}
}
并使用:
val activityRootView = findViewById<ViewGroup>(R.id.activityRoot)
KeyboardWatcher(activityRootView).observer = { visible ->
if (visible) do something here ...
}
其他回答
现在在Api 30级别上,应该这样做
final WindowMetrics metrics = windowManager.getCurrentWindowMetrics();
// Gets all excluding insets
final WindowInsets windowInsets = metrics.getWindowInsets();
Insets insets = windowInsets.getInsetsIgnoreVisibility(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);
(2012年的答案,可能已经过时了)如果你想支持前蜂窝,你需要在API 13之前引入向后兼容性。类似于:
int measuredWidth = 0;
int measuredHeight = 0;
WindowManager w = getWindowManager();
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR2) {
Point size = new Point();
w.getDefaultDisplay().getSize(size);
measuredWidth = size.x;
measuredHeight = size.y;
} else {
Display d = w.getDefaultDisplay();
measuredWidth = d.getWidth();
measuredHeight = d.getHeight();
}
当然,被弃用的方法最终会从最新的SDK中删除,但尽管我们仍然依赖大多数拥有Android 2.1、2.2和2.3的用户,但这就是我们剩下的。
为了访问Android设备的状态栏高度,我们更喜欢一种编程方式:
示例代码
int resId = getResources().getIdentifier("status_bar_height", "dimen", "android");
if (resId > 0) {
result = getResources().getDimensionPixelSize(resId);
}
变量结果给出像素的高度。
用于快速访问
有关标题栏、导航栏和内容视图高度的更多信息,请查看Android设备屏幕大小。
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;
}
我使用了上述建议,并为我们的问题创建了一个kotlin版本。希望这为使用科特林的人提供一些额外的帮助:
private val screenDimensions: Int by lazy {
val display = (context.getSystemService(Context.WINDOW_SERVICE) as WindowManager).defaultDisplay
Point()
.also { size ->
when {
Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1 -> display.getRealSize(size)
else -> display.getSize(size)
}
}
}
screenDimensions.x // width
screenDimensions.y // height