也有解决方案与系统嵌入，但它只适用于API >= 21 (Android L)。说你有BottomNavigationView，这是线性布局的孩子，你需要隐藏它时，键盘显示:

> LinearLayout
  > ContentView
  > BottomNavigationView

你所需要做的就是以这样的方式扩展LinearLayout:

public class KeyboardAwareLinearLayout extends LinearLayout {
    public KeyboardAwareLinearLayout(Context context) {
        super(context);
    }

    public KeyboardAwareLinearLayout(Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
    }

    public KeyboardAwareLinearLayout(Context context,
                                     @Nullable AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    public KeyboardAwareLinearLayout(Context context, AttributeSet attrs,
                                     int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
    }

    @Override
    public WindowInsets onApplyWindowInsets(WindowInsets insets) {
        int childCount = getChildCount();
        for (int index = 0; index < childCount; index++) {
            View view = getChildAt(index);
            if (view instanceof BottomNavigationView) {
                int bottom = insets.getSystemWindowInsetBottom();
                if (bottom >= ViewUtils.dpToPx(200)) {
                    // keyboard is shown
                    view.setVisibility(GONE);
                } else {
                    // keyboard is hidden
                    view.setVisibility(VISIBLE);
                }
            }
        }
        return insets;
    }
}

这个想法是，当键盘显示时，系统insets被改变为相当大的.bottom值。

我使用了与鲁班的答案略有不同的答案，事实证明在某些情况下更有帮助，特别是在使用高分辨率设备时。

final View activityRootView = findViewById(android.R.id.content);
activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(
        new OnGlobalLayoutListener() {
            @Override
            public void onGlobalLayout() {
                int heightView = activityRootView.getHeight();
                int widthView = activityRootView.getWidth();
                if (1.0 * widthView / heightView > 3) {
                    //Make changes for Keyboard not visible
                } else {
                    //Make changes for keyboard visible
                }
            }
        });

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 int DefaultKeyboardDP = 100;

        // From @nathanielwolf answer...  Lollipop includes button bar in the root. Add height of button bar (48dp) to maxDiff
        private final int EstimatedKeyboardDP = DefaultKeyboardDP + (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP ? 48 : 0);

        private final Rect r = new Rect();

        @Override
        public void onGlobalLayout() {
            // Convert the dp to pixels.
            int estimatedKeyboardHeight = (int) TypedValue
                    .applyDimension(TypedValue.COMPLEX_UNIT_DIP, EstimatedKeyboardDP, activityRootView.getResources().getDisplayMetrics());

            // Conclude whether the keyboard is shown or not.
            activityRootView.getWindowVisibleDisplayFrame(r);
            int heightDiff = activityRootView.getRootView().getHeight() - (r.bottom - r.top);
            boolean isShown = heightDiff >= estimatedKeyboardHeight;

            if (isShown == wasOpened) {
                Log.d("Keyboard state", "Ignoring global layout change...");
                return;
            }

            wasOpened = isShown;
            listener.onVisibilityChanged(isShown);
        }
    });
}

对我有用:)

注意: 如果你注意到DefaultKeyboardDP不适合你的设备播放的值，并发表评论，让每个人都知道应该是什么值…最终我们将得到适合所有设备的正确值!

要了解更多细节，请查看Cyborg上的实现

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)
    }
}

我的答案基本上与Kachi的答案相同，但我将它包装到一个很好的helper类中，以清理它在整个应用程序中的使用方式。

import android.app.Activity;
import android.app.Fragment;
import android.graphics.Rect;
import android.view.View;
import android.view.ViewTreeObserver.OnGlobalLayoutListener;

/**
 * Detects Keyboard Status changes and fires events only once for each change
 */
public class KeyboardStatusDetector {
    KeyboardVisibilityListener visibilityListener;

    boolean keyboardVisible = false;

    public void registerFragment(Fragment f) {
        registerView(f.getView());
    }

    public void registerActivity(Activity a) {
        registerView(a.getWindow().getDecorView().findViewById(android.R.id.content));
    }

    public KeyboardStatusDetector registerView(final View v) {
        v.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
            @Override
            public void onGlobalLayout() {
                Rect r = new Rect();
                v.getWindowVisibleDisplayFrame(r);

                int heightDiff = v.getRootView().getHeight() - (r.bottom - r.top);
                if (heightDiff > 100) { // if more than 100 pixels, its probably a keyboard...
                    /** Check this variable to debounce layout events */
                    if(!keyboardVisible) {
                        keyboardVisible = true;
                        if(visibilityListener != null) visibilityListener.onVisibilityChanged(true);
                    }
                } else {
                    if(keyboardVisible) {
                        keyboardVisible = false;
                        if(visibilityListener != null) visibilityListener.onVisibilityChanged(false);
                    }
                }
            }
        });

        return this;
    }

    public KeyboardStatusDetector setVisibilityListener(KeyboardVisibilityListener listener) {
        visibilityListener = listener;
        return this;
    }

    public static interface KeyboardVisibilityListener {
        public void onVisibilityChanged(boolean keyboardVisible);
    }
}

你可以使用它来检测整个应用程序中的键盘变化，如下所示:

    new KeyboardStatusDetector()
            .registerFragment(fragment)  //register to a fragment 
            .registerActivity(activity)  //or register to an activity
            .registerView(view)          //or register to a view
            .setVisibilityListener(new KeyboardVisibilityListener() {
                @Override
                public void onVisibilityChanged(boolean keyboardVisible) {
                    if(keyboardVisible) {
                       //Do stuff for keyboard visible
                    }else {
                       //Do stuff for keyboard hidden
                    }
                }
            });

注意:只使用一个“寄存器”调用。它们都是一样的，只是为了方便

一个不需要LayoutListener的方法

在我的情况下，我想在替换我的片段之前保存键盘的状态。我调用方法hideSoftInputFromWindow from onSaveInstanceState，它会关闭键盘并返回键盘是否可见。

这个方法很简单，但可能会改变键盘的状态。