尽管本页上投票最多的解决方案说，有一个setWindowInsetsAnimationCallback的ViewCompat版本一直工作到Android 21。

所以现在，这个解决方案的方法一直适用于21。

来源:https://developer.android.com/reference/androidx/core/view/ViewCompat setWindowInsetsAnimationCallback (android.view.View androidx.core.view.WindowInsetsAnimationCompat.Callback)

基于Nebojsa Tomcic的代码，我开发了以下relativelayout子类:

import java.util.ArrayList;

import android.content.Context;
import android.util.AttributeSet;
import android.widget.RelativeLayout;

public class KeyboardDetectorRelativeLayout extends RelativeLayout {

    public interface IKeyboardChanged {
        void onKeyboardShown();
        void onKeyboardHidden();
    }

    private ArrayList<IKeyboardChanged> keyboardListener = new ArrayList<IKeyboardChanged>();

    public KeyboardDetectorRelativeLayout(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    public KeyboardDetectorRelativeLayout(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public KeyboardDetectorRelativeLayout(Context context) {
        super(context);
    }

    public void addKeyboardStateChangedListener(IKeyboardChanged listener) {
        keyboardListener.add(listener);
    }

    public void removeKeyboardStateChangedListener(IKeyboardChanged listener) {
        keyboardListener.remove(listener);
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        final int proposedheight = MeasureSpec.getSize(heightMeasureSpec);
        final int actualHeight = getHeight();

        if (actualHeight > proposedheight) {
            notifyKeyboardShown();
        } else if (actualHeight < proposedheight) {
            notifyKeyboardHidden();
        }
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }

    private void notifyKeyboardHidden() {
        for (IKeyboardChanged listener : keyboardListener) {
            listener.onKeyboardHidden();
        }
    }

    private void notifyKeyboardShown() {
        for (IKeyboardChanged listener : keyboardListener) {
            listener.onKeyboardShown();
        }
    }

}

这工作得很好… 注意，当你的活动的软输入模式设置为" windowmanager . layoutparm . soft_input_adjust_resize "时，这个解决方案才会工作

我是这样做的:

添加OnKeyboardVisibilityListener接口。

public interface OnKeyboardVisibilityListener {
    void onVisibilityChanged(boolean visible);
}

HomeActivity.java:

public class HomeActivity extends Activity implements OnKeyboardVisibilityListener {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_sign_up);
    // Other stuff...
    setKeyboardVisibilityListener(this);
}

private void setKeyboardVisibilityListener(final OnKeyboardVisibilityListener onKeyboardVisibilityListener) {
    final View parentView = ((ViewGroup) findViewById(android.R.id.content)).getChildAt(0);
    parentView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {

        private boolean alreadyOpen;
        private final int defaultKeyboardHeightDP = 100;
        private final int EstimatedKeyboardDP = defaultKeyboardHeightDP + (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP ? 48 : 0);
        private final Rect rect = new Rect();

        @Override
        public void onGlobalLayout() {
            int estimatedKeyboardHeight = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, EstimatedKeyboardDP, parentView.getResources().getDisplayMetrics());
            parentView.getWindowVisibleDisplayFrame(rect);
            int heightDiff = parentView.getRootView().getHeight() - (rect.bottom - rect.top);
            boolean isShown = heightDiff >= estimatedKeyboardHeight;

            if (isShown == alreadyOpen) {
                Log.i("Keyboard state", "Ignoring global layout change...");
                return;
            }
            alreadyOpen = isShown;
            onKeyboardVisibilityListener.onVisibilityChanged(isShown);
        }
    });
}


@Override
public void onVisibilityChanged(boolean visible) {
    Toast.makeText(HomeActivity.this, visible ? "Keyboard is active" : "Keyboard is Inactive", Toast.LENGTH_SHORT).show();
  }
}

希望这对你有所帮助。

不确定是否有人发布这篇文章。发现这个解决方案简单易用!SoftKeyboard类在gi.github.com上。但是当键盘弹出/隐藏事件回调时，我们需要一个处理程序来正确地在UI上做事情:

/*
Somewhere else in your code
*/
RelativeLayout mainLayout = findViewById(R.layout.main_layout); // You must use your root layout
InputMethodManager im = (InputMethodManager) getSystemService(Service.INPUT_METHOD_SERVICE);

/*
Instantiate and pass a callback
*/
SoftKeyboard softKeyboard;
softKeyboard = new SoftKeyboard(mainLayout, im);
softKeyboard.setSoftKeyboardCallback(new SoftKeyboard.SoftKeyboardChanged()
{

    @Override
    public void onSoftKeyboardHide() 
    {
        // Code here
        new Handler(Looper.getMainLooper()).post(new Runnable() {
                @Override
                public void run() {
                    // Code here will run in UI thread
                    ...
                }
            });
    }

    @Override
    public void onSoftKeyboardShow() 
    {
        // Code here
        new Handler(Looper.getMainLooper()).post(new Runnable() {
                @Override
                public void run() {
                    // Code here will run in UI thread
                    ...
                }
            });

    }   
});

这可能不是最有效的解决方案。但这对我每次都有效……我调用这个函数每当我需要听软键盘。

boolean isOpened = false;

public void setListenerToRootView() {
    final View activityRootView = getWindow().getDecorView().findViewById(android.R.id.content);
    activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
        @Override
        public void onGlobalLayout() {

            int heightDiff = activityRootView.getRootView().getHeight() - activityRootView.getHeight();
            if (heightDiff > 100) { // 99% of the time the height diff will be due to a keyboard.
                Toast.makeText(getApplicationContext(), "Gotcha!!! softKeyboardup", 0).show();

                if (isOpened == false) {
                    //Do two things, make the view top visible and the editText smaller
                }
                isOpened = true;
            } else if (isOpened == true) {
                Toast.makeText(getApplicationContext(), "softkeyborad Down!!!", 0).show();
                isOpened = false;
            }
        }
    });
}

注意: 如果用户使用浮动键盘，这种方法将导致问题。

如果你想从你的活动中处理IMM(虚拟)键盘窗口的显示/隐藏，你需要子类化你的布局并覆盖onMesure方法(这样你就可以确定你的布局的测量宽度和测量高度)。之后，通过setContentView()将子类布局设置为Activity的主视图。现在您将能够处理IMM显示/隐藏窗口事件。也许这听起来很复杂，但事实并非如此。代码如下:

main。xml

   <?xml version="1.0" encoding="utf-8"?>
   <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:orientation="horizontal" >
        <EditText
             android:id="@+id/SearchText" 
             android:text="" 
             android:inputType="text"
             android:layout_width="fill_parent"
             android:layout_height="34dip"
             android:singleLine="True"
             />
        <Button
             android:id="@+id/Search" 
             android:layout_width="60dip"
             android:layout_height="34dip"
             android:gravity = "center"
             />
    </LinearLayout>

现在在布局的Activity声明子类中(main.xml)

    public class MainSearchLayout extends LinearLayout {

    public MainSearchLayout(Context context, AttributeSet attributeSet) {
        super(context, attributeSet);
        LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        inflater.inflate(R.layout.main, this);
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        Log.d("Search Layout", "Handling Keyboard Window shown");

        final int proposedheight = MeasureSpec.getSize(heightMeasureSpec);
        final int actualHeight = getHeight();

        if (actualHeight > proposedheight){
            // Keyboard is shown

        } else {
            // Keyboard is hidden
        }
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }
}

您可以从代码中看到，我们在子类构造函数中为Activity扩展布局

inflater.inflate(R.layout.main, this);

现在只需设置Activity的子类布局的内容视图。

public class MainActivity extends Activity {

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        MainSearchLayout searchLayout = new MainSearchLayout(this, null);

        setContentView(searchLayout);
    }

    // rest of the Activity code and subclassed layout...

}