Android系统中是否有一种方法可以检测软件(也就是Android。“软”)键盘在屏幕上可见吗?


当前回答

There is a direct method to find this out. And, it does not require the layout changes. So it works in immersive fullscreen mode, too. But, unfortunately, it does not work on all devices. So you have to test it with your device(s). The trick is that you try to hide or show the soft keyboard and capture the result of that try. If it works correct then the keyboard is not really shown or hidden. We just ask for the state. To stay up-to-date, you simply repeat this operation, e.g. every 200 milliseconds, using a Handler. The implementation below does just a single check. If you do multiple checks, then you should enable all the (_keyboardVisible) tests.

public interface OnKeyboardShowHide
{
    void    onShowKeyboard( Object param );
    void    onHideKeyboard( Object param );
}

private static Handler      _keyboardHandler    = new Handler();
private boolean             _keyboardVisible    = false;
private OnKeyboardShowHide  _keyboardCallback;
private Object              _keyboardCallbackParam;

public void start( OnKeyboardShowHide callback, Object callbackParam )
{
    _keyboardCallback      = callback;
    _keyboardCallbackParam = callbackParam;
    //
    View view = getCurrentFocus();
    if (view != null)
    {
        InputMethodManager imm = (InputMethodManager) getSystemService( Activity.INPUT_METHOD_SERVICE );
        imm.hideSoftInputFromWindow( view.getWindowToken(), InputMethodManager.HIDE_IMPLICIT_ONLY, _keyboardResultReceiver );
        imm.showSoftInput( view, InputMethodManager.SHOW_IMPLICIT, _keyboardResultReceiver );
    }
    else // if (_keyboardVisible)
    {
        _keyboardVisible = false;
        _keyboardCallback.onHideKeyboard( _keyboardCallbackParam );
    }
}

private ResultReceiver      _keyboardResultReceiver = new ResultReceiver( _keyboardHandler )
{
    @Override
    protected void onReceiveResult( int resultCode, Bundle resultData )
    {
        switch (resultCode)
        {
            case InputMethodManager.RESULT_SHOWN :
            case InputMethodManager.RESULT_UNCHANGED_SHOWN :
                // if (!_keyboardVisible)
                {
                    _keyboardVisible = true;
                    _keyboardCallback.onShowKeyboard( _keyboardCallbackParam );
                }
                break;
            case InputMethodManager.RESULT_HIDDEN :
            case InputMethodManager.RESULT_UNCHANGED_HIDDEN :
                // if (_keyboardVisible)
                {
                    _keyboardVisible = false;
                    _keyboardCallback.onHideKeyboard( _keyboardCallbackParam );
                }
                break;
        }
    }
};

其他回答

可以使用showSoftInput()和hideSoftInput()的回调结果来检查键盘的状态。完整的细节和示例代码在

https://rogerkeays.com/how-to-check-if-the-software-keyboard-is-shown-in-android

我是这样做的,但只有当你的目标是关闭/打开键盘时,它才有意义。

关闭示例:(检查键盘是否已经关闭,如果没有关闭)

imm.showSoftInput(etSearch, InputMethodManager.HIDE_IMPLICIT_ONLY, new ResultReceiver(null) {
                    @Override
                    protected void onReceiveResult(int resultCode, Bundle resultData) {
                        super.onReceiveResult(resultCode, resultData);
                        if (resultCode != InputMethodManager.RESULT_UNCHANGED_HIDDEN)
                            imm.toggleSoftInput(InputMethodManager.SHOW_FORCED, 0);
                    }
                });

所以,在花了很长一段时间摆弄accesessibilityservices、窗口嵌入、屏幕高度检测等之后,我想我找到了一种方法来做到这一点。

免责声明:它在Android中使用了一个隐藏的方法,这意味着它可能不一致。然而,在我的测试中,它似乎有效。

该方法是InputMethodManager#getInputMethodWindowVisibleHeight(),它自Lollipop(5.0)以来就存在了。

调用它将返回当前键盘的高度(以像素为单位)。理论上,键盘不应该是0像素高,所以我做了一个简单的高度检查(在Kotlin中):

val imm by lazy { context.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager }
if (imm.inputMethodWindowVisibleHeight > 0) {
    //keyboard is shown
else {
    //keyboard is hidden
}

当我调用隐藏方法时,我使用Android隐藏API来避免反射(我为我开发的应用程序做了很多,这些应用程序主要是hack /tuner应用程序),但这应该也是可能的反射:

val imm by lazy { context.getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager }
val windowHeightMethod = InputMethodManager::class.java.getMethod("getInputMethodWindowVisibleHeight")
val height = windowHeightMethod.invoke(imm) as Int
//use the height val in your logic

A可能会使用:

@Override
public void onConfigurationChanged(Configuration newConfig) {
    super.onConfigurationChanged(newConfig);

    Log.d(
    getClass().getSimpleName(), 
    String.format("conf: %s", newConfig));

    if (newConfig.hardKeyboardHidden != hardKeyboardHidden) {
        onHardwareKeyboardChange(newConfig.hardKeyboardHidden);

        hardKeyboardHidden = newConfig.hardKeyboardHidden;
    }

    if (newConfig.keyboardHidden != keyboardHidden) {
        onKeyboardChange(newConfig.keyboardHidden);

        keyboardHidden = newConfig.hardKeyboardHidden;
    }

}

public static final int KEYBOARDHIDDEN_UNDEFINED = 0;
public static final int KEYBOARDHIDDEN_NO = 1;
public static final int KEYBOARDHIDDEN_YES = 2;
public static final int KEYBOARDHIDDEN_SOFT = 3;

//todo
private void onKeyboardChange(int keyboardHidden) {

}

//todo
private void onHardwareKeyboardChange(int hardKeyboardHidden) {

}

我也遇到过类似的问题。我需要对屏幕上的Enter按钮做出反应(这隐藏了键盘)。在这种情况下,你可以订阅键盘打开的文本视图的OnEditorAction -如果你有多个可编辑框,那么就订阅所有的文本视图。

在你的活动中,你可以完全控制键盘,所以如果你监听所有打开和关闭事件,你就不会面临键盘是否打开的问题。