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。

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。

2020年更新

这现在是可能的:

在Android 11上，你可以这样做

view.setWindowInsetsAnimationCallback(object : WindowInsetsAnimation.Callback {
    override fun onEnd(animation: WindowInsetsAnimation) {
        super.onEnd(animation)
        val showingKeyboard = view.rootWindowInsets.isVisible(WindowInsets.Type.ime())
        // now use the boolean for something
    }
})

你也可以听显示/隐藏键盘的动画，并做相应的转换。

我建议阅读Android 11预览版和相应的文档

Android 11之前

但是，这项工作还没有Compat版本，所以您需要求助于黑客。

你可以得到窗口的insets，如果底部的insets大于一些值，你认为是合理的(通过实验)，你可以认为这是显示键盘。这不是很好，在某些情况下可能会失败，但没有框架支持这一点。

这是对这个确切问题的一个很好的回答https://stackoverflow.com/a/36259261/372076。或者，这里有一个页面给出了一些不同的方法来实现这个在Android 11之前:

https://developer.salesforce.com/docs/atlas.en-us.noversion.service_sdk_android.meta/service_sdk_android/android_detecting_keyboard.htm

Note

此解决方案不适用于软键盘和 onConfigurationChanged将不会被soft (virtual)调用 键盘。

您必须自己处理配置更改。

http://developer.android.com/guide/topics/resources/runtime-changes.html#HandlingTheChange

示例:

// from the link above
@Override
public void onConfigurationChanged(Configuration newConfig) {
    super.onConfigurationChanged(newConfig);

    
    // Checks whether a hardware keyboard is available
    if (newConfig.hardKeyboardHidden == Configuration.HARDKEYBOARDHIDDEN_NO) {
        Toast.makeText(this, "keyboard visible", Toast.LENGTH_SHORT).show();
    } else if (newConfig.hardKeyboardHidden == Configuration.HARDKEYBOARDHIDDEN_YES) {
        Toast.makeText(this, "keyboard hidden", Toast.LENGTH_SHORT).show();
    }
}

然后只需更改一些视图的可见性，更新字段，并更改布局文件。

你也可以检查第一个DecorView的子底部填充。当键盘显示时，它将被设置为非零值。

@Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
    View view = getRootView();
    if (view != null && (view = ((ViewGroup) view).getChildAt(0)) != null) {
        setKeyboardVisible(view.getPaddingBottom() > 0);
    }
    super.onLayout(changed, left, top, right, bottom);
}

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
                    ...
                }
            });

    }   
});

使用viewTreeObserver轻松获取键盘事件。

layout_parent.viewTreeObserver.addOnGlobalLayoutListener {
            val r = Rect()
            layout_parent.getWindowVisibleDisplayFrame(r)
            if (layout_parent.rootView.height - (r.bottom - r.top) > 100) { // if more than 100 pixels, its probably a keyboard...
                Log.e("TAG:", "keyboard open")
            } else {
                Log.e("TAG:", "keyboard close")
            }
        }

** layout_parent是你的视图，比如edit_text.parent