一个基于@bohdan-oliynyk答案的更紧凑的Kotlin版本

private const val KEYBOARD_VISIBLE_THRESHOLD_DP = 100

fun Activity.isKeyboardOpen(): Boolean {
    fun convertDpToPx(value: Int): Int =
        (value * Resources.getSystem().displayMetrics.density).toInt()

    val rootView = findViewById<View>(android.R.id.content)
    val visibleThreshold = Rect()
    rootView.getWindowVisibleDisplayFrame(visibleThreshold)
    val heightDiff = rootView.height - visibleThreshold.height()

    val accessibleValue = convertDpToPx(KEYBOARD_VISIBLE_THRESHOLD_DP)

    return heightDiff > accessibleValue
}

fun Activity.isKeyboardClosed(): Boolean {
    return isKeyboardOpen().not()
}

private fun isKeyboardVisible(rootView: View) =
    ViewCompat.getRootWindowInsets(rootView)!!.isVisible(WindowInsetsCompat.Type.ime())

非常容易

1. 把id放在根视图上

rootView只是一个视图指向我的根视图在这种情况下，一个相对布局:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:id="@+id/addresses_confirm_root_view"
                android:background="@color/WHITE_CLR">

2. 在Activity中初始化根视图:

RelativeLayout rootView = (RelativeLayout) findViewById(R.id.addresses_confirm_root_view);

3.使用getViewTreeObserver()检测键盘是否打开或关闭

    rootView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
            @Override
            public void onGlobalLayout() {
                int heightDiff = rootView.getRootView().getHeight() - rootView.getHeight();
                
                if (heightDiff > 100) { // Value should be less than keyboard's height 
                    Log.e("MyActivity", "keyboard opened");
                } else { 
                    Log.e("MyActivity", "keyboard closed");
                }
            }
        });

试试这个:

InputMethodManager imm = (InputMethodManager) getActivity()
            .getSystemService(Context.INPUT_METHOD_SERVICE);

    if (imm.isAcceptingText()) {
        writeToLog("Software Keyboard was shown");
    } else {
        writeToLog("Software Keyboard was not shown");
    }

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;
        }
    }
};

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
}