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

我把答案转换为kotlin,希望这对kotlin用户有帮助。

private fun checkKeyboardVisibility() {
    var isKeyboardShowing = false

    binding.coordinator.viewTreeObserver.addOnGlobalLayoutListener {
        val r = Rect()
        binding.coordinator.getWindowVisibleDisplayFrame(r)
        val screenHeight = binding.coordinator.rootView.height

        // r.bottom is the position above soft keypad or device button.
        // if keypad is shown, the r.bottom is smaller than that before.
        val keypadHeight = screenHeight - r.bottom


        if (keypadHeight > screenHeight * 0.15) { // 0.15 ratio is perhaps enough to determine keypad height.
            // keyboard is opened
            if (!isKeyboardShowing) {
                isKeyboardShowing = true

            }
        } else {
            // keyboard is closed
            if (isKeyboardShowing) {
                isKeyboardShowing = false

            }
        }
    }
}

其他回答

在我的情况下,我只有一个编辑文本来管理我的布局,所以我想出了这个解决方案。 它工作得很好,基本上它是一个自定义的EditText,它监听焦点,并在焦点改变或按下后退/完成按钮时发送本地广播。 要工作,你需要在你的布局与android: focableintouchmode ="true"和android:focusableInTouchMode="true",因为当你调用clearFocus()的焦点将被重新分配到第一个可聚焦的视图。 虚拟视图示例:

<View
android:layout_width="1dp"
android:layout_height="1dp"
android:focusable="true"
android:focusableInTouchMode="true"/>

额外的信息

检测布局变化差异的解决方案效果不太好,因为它强烈依赖于屏幕密度,因为100px在某些设备上可能很大,而在其他设备上可能没有,你可能会得到误报。 另外,不同的厂商有不同的键盘。

final View activityRootView = findViewById(R.id.rootlayout);
activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
        @Override
        public void onGlobalLayout() {

            Rect r = new Rect();
            activityRootView.getWindowVisibleDisplayFrame(r);

            int screenHeight = activityRootView.getRootView().getHeight();
            Log.e("screenHeight", String.valueOf(screenHeight));
            int heightDiff = screenHeight - (r.bottom - r.top);
            Log.e("heightDiff", String.valueOf(heightDiff));
            boolean visible = heightDiff > screenHeight / 3;
            Log.e("visible", String.valueOf(visible));
            if (visible) {
                Toast.makeText(LabRegister.this, "I am here 1", Toast.LENGTH_SHORT).show();
            } else {
                Toast.makeText(LabRegister.this, "I am here 2", Toast.LENGTH_SHORT).show();
            }
        }
});

它使用活动的adjustNothing标志和使用生命周期事件。还有Kotlin:

/**
 * This class uses a PopupWindow to calculate the window height when the floating keyboard is opened and closed
 *
 * @param activity The parent activity
 *  The root activity that uses this KeyboardManager
 */
class KeyboardManager(private val activity: AppCompatActivity) : PopupWindow(activity), LifecycleObserver {

    private var observerList = mutableListOf<((keyboardTop: Int) -> Unit)>()

    /** The last value of keyboardTop */
    private var keyboardTop: Int = 0

    /** The view that is used to calculate the keyboard top  */
    private val popupView: View?

    /** The parent view  */
    private var parentView: View

    var isKeyboardShown = false
        private set

    /**
     * Create transparent view which will be stretched over to the full screen
     */
    private fun createFullScreenView(): View {
        val view = LinearLayout(activity)
        view.layoutParams = LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,
                ViewGroup.LayoutParams.MATCH_PARENT)
        view.background = ColorDrawable(Color.TRANSPARENT)
        return view
    }

    init {
        this.popupView = createFullScreenView()
        contentView = popupView

        softInputMode = LayoutParams.SOFT_INPUT_ADJUST_RESIZE or LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE
        inputMethodMode = INPUT_METHOD_NEEDED

        parentView = activity.findViewById(android.R.id.content)

        width = 0
        height = LayoutParams.MATCH_PARENT

        popupView.viewTreeObserver.addOnGlobalLayoutListener {
            val rect = Rect()
            popupView.getWindowVisibleDisplayFrame(rect)

            val keyboardTop = rect.bottom
            if (this.keyboardTop != keyboardTop) {
                isKeyboardShown = keyboardTop < this.keyboardTop
                this.keyboardTop = keyboardTop
                observerList.forEach { it(keyboardTop) }
            }
        }
        activity.lifecycle.addObserver(this)
    }

    /**
     * This must be called after the onResume of the Activity or inside view.post { } .
     * PopupWindows are not allowed to be registered before the onResume has finished
     * of the Activity
     */
    @OnLifecycleEvent(Lifecycle.Event.ON_RESUME)
    fun start() {
        parentView.post {
            if (!isShowing && parentView.windowToken != null) {
                setBackgroundDrawable(ColorDrawable(0))
                showAtLocation(parentView, Gravity.NO_GRAVITY, 0, 0)
            }
        }
    }

    /**
     * This manager will not be used anymore
     */
    @OnLifecycleEvent(Lifecycle.Event.ON_DESTROY)
    fun close() {
        activity.lifecycle.removeObserver(this)
        observerList.clear()
        dismiss()
    }

    /**
     * Set the keyboard top observer. The observer will be notified when the keyboard top has changed.
     * For example when the keyboard is opened or closed
     *
     * @param observer The observer to be added to this provider
     */
    fun registerKeyboardTopObserver(observer: (keyboardTop: Int) -> Unit) {
        observerList.add(observer)
    }
}

有用的方法,保持视图始终高于键盘

fun KeyboardManager.updateBottomMarginIfKeyboardShown(
        view: View,
        activity: AppCompatActivity,
        // marginBottom of view when keyboard is hide
        marginBottomHideKeyboard: Int,
        // marginBottom of view when keybouard is shown
        marginBottomShowKeyboard: Int
) {
    registerKeyboardTopObserver { bottomKeyboard ->
        val bottomView = ViewUtils.getFullViewBounds(view).bottom
        val maxHeight = ScreenUtils.getFullScreenSize(activity.windowManager).y
        // Check that view is within the window size
        if (bottomView < maxHeight) {
            if (bottomKeyboard < bottomView) {
                ViewUtils.updateMargin(view, bottomMargin = bottomView - bottomKeyboard +
                        view.marginBottom + marginBottomShowKeyboard)
            } else ViewUtils.updateMargin(view, bottomMargin = marginBottomHideKeyboard)
        }
    }
}

在getFullViewBounds

fun getLocationOnScreen(view: View): Point {
    val location = IntArray(2)
    view.getLocationOnScreen(location)
    return Point(location[0], location[1])
}

fun getFullViewBounds(view: View): Rect {
     val location = getLocationOnScreen(view)
     return Rect(location.x, location.y, location.x + view.width,
            location.y + view.height)
 }

在getFullScreenSize

fun getFullScreenSize(wm: WindowManager? = null) =
            getScreenSize(wm) { getRealSize(it) }

private fun getScreenSize(wm: WindowManager? = null, block: Display.(Point) -> Unit): Point {
    val windowManager = wm ?: App.INSTANCE.getSystemService(Context.WINDOW_SERVICE)
            as WindowManager
    val point = Point()
    windowManager.defaultDisplay.block(point)
    return point
}

其中更新边距

fun updateMargin(
        view: View,
        leftMargin: Int? = null,
        topMargin: Int? = null,
        rightMargin: Int? = null,
        bottomMargin: Int? = null
) {
    val layoutParams = view.layoutParams as ViewGroup.MarginLayoutParams
    if (leftMargin != null) layoutParams.leftMargin = leftMargin
    if (topMargin != null) layoutParams.topMargin = topMargin
    if (rightMargin != null) layoutParams.rightMargin = rightMargin
    if (bottomMargin != null) layoutParams.bottomMargin = bottomMargin
    view.layoutParams = layoutParams
}

如你所知,android软件的键盘只有在有可能的输入事件时才可见。换句话说,只有当EditText被聚焦时,键盘才可见。这意味着你可以通过使用OnFocusChangeListener获得键盘是否可见。

//Declare this Globally

public boolean isKeyBoardVisible = false;

//In OnCreate *[For Activity]*, OnCreateView *[For Fragment]*

text_send.setOnFocusChangeListener(new View.OnFocusChangeListener() {

    @Override
    public void onFocusChange(View v, boolean hasFocus) {
        if(hasFocus)
            isKeyBoardVisible = true;
        else
            isKeyBoardVisible = false;
    }
});

现在你可以在类的任何地方使用isKeyBoardVisible变量来获取键盘是否打开。这对我来说很有效。

注意:当使用InputMethodManager以编程方式打开键盘时,这个过程不起作用,因为它不调用OnFocusChangeListener。

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;
        }
    }
};