我需要做一件非常简单的事情-找出软件键盘是否显示。这在Android中可行吗?
当前回答
参考@TacB0sS的回答,我在Kotlin中开发了一个类。希望这对你有所帮助。如果需要改进,请告诉我。
class KeyboardVisibilityObserver(val layRootContainer: View?, val keyboardVisibilityListener: KeyboardVisibilityListener?) {
var isKeyboardOpen = false
private set
private var keyBoardObserver = object : ViewTreeObserver.OnGlobalLayoutListener {
private val DefaultKeyboardDP = 100
// Lollipop includes button bar in the root. Add height of button bar (48dp) to maxDiff
private val EstimatedKeyboardDP = DefaultKeyboardDP + if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) 48 else 0
private val r = Rect()
override fun onGlobalLayout() {
if (layRootContainer != null) {
// Convert the dp to pixels.
val estimatedKeyboardHeight = TypedValue
.applyDimension(TypedValue.COMPLEX_UNIT_DIP, EstimatedKeyboardDP.toFloat(), layRootContainer.resources.displayMetrics).toInt()
// Conclude whether the keyboard is shown or not.
layRootContainer.getWindowVisibleDisplayFrame(r)
val heightDiff = layRootContainer.rootView.height - (r.bottom - r.top)
val isShown = heightDiff >= estimatedKeyboardHeight
if (isShown == isKeyboardOpen) {
// Log.d("Keyboard state", "Ignoring global layout change...");
return
}
isKeyboardOpen = isShown
keyboardVisibilityListener?.onKeyboardVisibilityChanged(isKeyboardOpen)
}
}
}
init {
layRootContainer?.viewTreeObserver?.addOnGlobalLayoutListener(keyBoardObserver)
}
// call this in onDestroy
fun removeObserver(){
layRootContainer?.viewTreeObserver?.removeOnGlobalLayoutListener(keyBoardObserver)
}
interface KeyboardVisibilityListener {
fun onKeyboardVisibilityChanged(isKeyboardOpen: Boolean)
}
}
其他回答
除了正确的答案,我必须在onCreateView的末尾添加这个,当使用一个片段内的webview。
getActivity().getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_ADJUST_PAN);
可能是因为我在一个片段中运行Webview,或者可能是API 30上的一个新行为,我的问题是,即使显示键盘,片段的高度也从未改变。
所以对于Fragment,整个代码应该是
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = super.onCreateView(inflater, container, savedInstanceState);
//mWebView.postUrl("https://www.google.com/");
final View activityRootView = view;
layoutListener = new ViewTreeObserver.OnGlobalLayoutListener() {
@Override
public void onGlobalLayout() {
Rect r = new Rect();
//r will be populated with the coordinates of your view that area still visible.
activityRootView.getWindowVisibleDisplayFrame(r);
// This variable was created only for Debug purposes and
// to see the height change when clicking on a field inside mWebView
int screenHeight = activityRootView.getRootView().getHeight();
Log.d("onGlobalLayout", "rect: " + r.toString());
Log.d("onGlobalLayout", "screenHeight: " + screenHeight);
//The difference on the heights from bottom to top and on the root height
int heightDiff = screenHeight - (r.bottom - r.top);
Log.d("onGlobalLayout", "heightDiff: " + heightDiff);
//I suggest to put 250 on resources to have better order
float dpx = dpToPx(getActivity(), 250);
if (previousHeightDiff != heightDiff) {
if (heightDiff > dpx) {
isSoftKeyboardPresent = true;
} else {
isSoftKeyboardPresent = false;
}
previousHeightDiff = heightDiff;
}
}
};
activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(layoutListener);
getActivity().getWindow().setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_ADJUST_PAN);
return view;
}
private static float dpToPx(Context context, float valueInDp) {
DisplayMetrics metrics = context.getResources().getDisplayMetrics();
return TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, valueInDp, metrics);
}
有一种直接的方法可以找出答案。而且,它不需要任何布局更改。 所以,它也可以在沉浸式全屏模式下工作。 诀窍在于,您尝试隐藏或显示软键盘,并捕获尝试的结果。 没有恐慌,这并不真正显示或隐藏键盘。我们只要求状态。 为了保持最新,您可以简单地重复操作,例如,每200毫秒,使用处理器。 您可以在这里找到一个实现:https://stackoverflow.com/a/27567074/2525452
有一个隐藏的方法可以帮助这个,inputmethodmanager。getinputmethodwindowvisibleheight。但我不知道为什么要藏起来。
import android.content.Context
import android.os.Handler
import android.view.inputmethod.InputMethodManager
class SoftKeyboardStateWatcher(private val ctx: Context) {
companion object {
private const val DELAY = 10L
}
private val handler = Handler()
private var isSoftKeyboardOpened: Boolean = false
private val height: Int
get() {
val imm = ctx.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
val method = imm.javaClass.getMethod("getInputMethodWindowVisibleHeight")
method.isAccessible = true
return method.invoke(imm) as Int
}
private val task: Runnable by lazy {
Runnable {
start()
if (!isSoftKeyboardOpened && height > 0) {
isSoftKeyboardOpened = true
notifyOnSoftKeyboardOpened(height)
} else if (isSoftKeyboardOpened && height == 0) {
isSoftKeyboardOpened = false
notifyOnSoftKeyboardClosed()
}
}
}
var listener: SoftKeyboardStateListener? = null
interface SoftKeyboardStateListener {
fun onSoftKeyboardOpened(keyboardHeightInPx: Int)
fun onSoftKeyboardClosed()
}
fun start() {
handler.postDelayed(task, DELAY)
}
fun stop() {
handler.postDelayed({
if (!isSoftKeyboardOpened) handler.removeCallbacks(task)
}, DELAY * 10)
}
private fun notifyOnSoftKeyboardOpened(keyboardHeightInPx: Int) {
listener?.onSoftKeyboardOpened(keyboardHeightInPx)
}
private fun notifyOnSoftKeyboardClosed() {
listener?.onSoftKeyboardClosed()
}
}
这个解决方案可能会重新打开键盘,但它是有效的。
InputMethodManager inputManager = ( (InputMethodManager) this.getSystemService(Context.INPUT_METHOD_SERVICE) );
private boolean isKeyboardShowing() {
boolean isKeyboardShowing = inputManager.hideSoftInputFromWindow(irrelevantView.getWindowToken(), 0);
if (isKeyboardShowing) {
inputManager.showSoftInput(this.getCurrentFocus(), 0);
}
return isKeyboardShowing;
}
就计算机而言,这是永远的问题,但这个问题仍然令人难以置信地相关! 所以我把上面的答案结合起来,做了一些改进……
public interface OnKeyboardVisibilityListener {
void onVisibilityChanged(boolean visible);
}
public final void setKeyboardListener(final OnKeyboardVisibilityListener listener) {
final View activityRootView = ((ViewGroup) getActivity().findViewById(android.R.id.content)).getChildAt(0);
activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
private boolean wasOpened;
private final Rect r = new Rect();
@Override
public void onGlobalLayout() {
activityRootView.getWindowVisibleDisplayFrame(r);
int heightDiff = activityRootView.getRootView().getHeight() - (r.bottom - r.top);
boolean isOpen = heightDiff > 100;
if (isOpen == wasOpened) {
logDebug("Ignoring global layout change...");
return;
}
wasOpened = isOpen;
listener.onVisibilityChanged(isOpen);
}
});
}
这对我很管用。
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