我知道这是一篇老文章，但我认为这是我所知道的最简单的方法，我的测试设备是Nexus 5。我还没有在其他设备上尝试过。希望其他人会分享他们的方法，如果他们发现我的代码不好:)

public static boolean isKeyboardShown(Context context, View view) {
        if (context == null || view == null) {
            return false;
        }
        InputMethodManager imm = (InputMethodManager) context
                .getSystemService(Context.INPUT_METHOD_SERVICE);
        return imm.hideSoftInputFromWindow(view.getWindowToken(), 0); 
}

imm。hideSoftInputFromWindow返回布尔值。

谢谢,

2012年1月25日新增答案

写了下面的答案后，有人告诉我ViewTreeObserver和其他api的存在，这些api从版本1开始就潜伏在SDK中。

而不是需要一个自定义的布局类型，一个更简单的解决方案是给你的活动的根视图一个已知的ID，比如@+ ID /activityRoot，钩子一个GlobalLayoutListener到ViewTreeObserver，并从那里计算你的活动的视图根和窗口大小之间的大小差:

final View activityRootView = findViewById(R.id.activityRoot);
activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
    @Override
    public void onGlobalLayout() {
        int heightDiff = activityRootView.getRootView().getHeight() - activityRootView.getHeight();
        if (heightDiff > dpToPx(this, 200)) { // if more than 200 dp, it's probably a keyboard...
            // ... do something here
        }
     }
});

使用一个实用程序，如:

public static float dpToPx(Context context, float valueInDp) {
    DisplayMetrics metrics = context.getResources().getDisplayMetrics();
    return TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, valueInDp, metrics);
}

简单!

注意: 你的应用程序必须在Android Manifest中设置这个标志Android:windowSoftInputMode=" adjuststresize "否则上述解决方案将无法工作。

原来的答案

是的，这是可能的，但它比应该的要难得多。

如果我需要关心键盘何时出现和消失(这是相当经常的)，那么我所做的是自定义我的顶级布局类为一个覆盖onMeasure()。基本逻辑是，如果布局发现自己填充的面积明显小于窗口的总面积，那么可能显示了软键盘。

import android.app.Activity;
import android.content.Context;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.widget.LinearLayout;

/*
 * LinearLayoutThatDetectsSoftKeyboard - a variant of LinearLayout that can detect when 
 * the soft keyboard is shown and hidden (something Android can't tell you, weirdly). 
 */

public class LinearLayoutThatDetectsSoftKeyboard extends LinearLayout {

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

    public interface Listener {
        public void onSoftKeyboardShown(boolean isShowing);
    }
    private Listener listener;
    public void setListener(Listener listener) {
        this.listener = listener;
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        int height = MeasureSpec.getSize(heightMeasureSpec);
        Activity activity = (Activity)getContext();
        Rect rect = new Rect();
        activity.getWindow().getDecorView().getWindowVisibleDisplayFrame(rect);
        int statusBarHeight = rect.top;
        int screenHeight = activity.getWindowManager().getDefaultDisplay().getHeight();
        int diff = (screenHeight - statusBarHeight) - height;
        if (listener != null) {
            listener.onSoftKeyboardShown(diff>128); // assume all soft keyboards are at least 128 pixels high
        }
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);       
    }

    }

然后在活动课上…

public class MyActivity extends Activity implements LinearLayoutThatDetectsSoftKeyboard.Listener {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        ...
        LinearLayoutThatDetectsSoftKeyboard mainLayout = (LinearLayoutThatDetectsSoftKeyboard)findViewById(R.id.main);
        mainLayout.setListener(this);
        ...
    }


    @Override
    public void onSoftKeyboardShown(boolean isShowing) {
        // do whatever you need to do here
    }

    ...
}

不要编写任何硬代码。最好的方法是，你必须调整你的视图，而Get Focus on EditText与键盘显示。 您可以使用下面的代码将活动上的resize属性添加到清单文件中。

android: windowSoftInputMode = adjustResize”

这是我的解决方案，它很有效。而不是寻找像素大小，只是检查内容视图的高度是否改变:

// Scroll to the latest comment whenever the keyboard is shown
commentsContent.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {

        private int oldHeight;

        @Override
        public void onGlobalLayout() {
            int newHeight = commentsContent.getMeasuredHeight();
            if (newHeight < oldHeight) {
                // Check for the keyboard showing in case the height difference
                // is a result of orientation change
                if (isSoftKeyboardShowing(CommentsActivity.this)) {
                    // Keyboard is showing so scroll to the latest comment
                    scrollToLatestComment();
                }
            }
            oldHeight = newHeight;
        }

    });


public static boolean isSoftKeyboardShowing(Activity activity) {
    InputMethodManager inputMethodManager = (InputMethodManager) activity.getSystemService(Activity.INPUT_METHOD_SERVICE);
    return inputMethodManager.isActive();
}

这段代码工作得很好

根视图使用这个类:

public class KeyboardConstraintLayout extends ConstraintLayout {

private KeyboardListener keyboardListener;
private EditText targetEditText;
private int minKeyboardHeight;
private boolean isShow;

public KeyboardConstraintLayout(Context context) {
    super(context);
    minKeyboardHeight = getResources().getDimensionPixelSize(R.dimen.keyboard_min_height);
}

public KeyboardConstraintLayout(Context context, AttributeSet attrs) {
    super(context, attrs);
    minKeyboardHeight = getResources().getDimensionPixelSize(R.dimen.keyboard_min_height);
}

public KeyboardConstraintLayout(Context context, AttributeSet attrs, int defStyleAttr) {
    super(context, attrs, defStyleAttr);
    minKeyboardHeight = getResources().getDimensionPixelSize(R.dimen.keyboard_min_height);
}

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    if (!isInEditMode()) {
        Activity activity = (Activity) getContext();
        @SuppressLint("DrawAllocation")
        Rect rect = new Rect();
        getWindowVisibleDisplayFrame(rect);

        int statusBarHeight = rect.top;
        int keyboardHeight = activity.getWindowManager().getDefaultDisplay().getHeight() - (rect.bottom - rect.top) - statusBarHeight;

        if (keyboardListener != null && targetEditText != null && targetEditText.isFocused()) {
            if (keyboardHeight > minKeyboardHeight) {
                if (!isShow) {
                    isShow = true;
                    keyboardListener.onKeyboardVisibility(true);
                }
            }else {
                if (isShow) {
                    isShow = false;
                    keyboardListener.onKeyboardVisibility(false);
                }
            }
        }
    }
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}

public boolean isShowKeyboard() {
    return isShow;
}

public void setKeyboardListener(EditText targetEditText, KeyboardListener keyboardListener) {
    this.targetEditText = targetEditText;
    this.keyboardListener = keyboardListener;
}

public interface KeyboardListener {
    void onKeyboardVisibility (boolean isVisible);
}

}

在activity或fragment中设置键盘监听器:

    rootLayout.setKeyboardListener(targetEditText, new KeyboardConstraintLayout.KeyboardListener() {
    @Override
    public void onKeyboardVisibility(boolean isVisible) {

    }
});

Reuben Scratton和Kachi提供的解决方案似乎依赖于设备的像素密度，如果你有一个高密度的设备，即使按下键盘，高度差也可能超过100。围绕这一点的工作将是看到初始高度差(键盘向下)，然后与当前的差异进行比较。

boolean isOpened = false;
int firstHeightDiff = -1;

public void setListenerToRootView(){
    final View activityRootView = getActivity().getWindow().getDecorView().findViewById(android.R.id.content);
    Rect r = new Rect();
    activityRootView.getWindowVisibleDisplayFrame(r);
    firstHeightDiff = activityRootView.getRootView().getHeight() - (r.bottom - r.top);
    activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
        @Override
        public void onGlobalLayout() {
            if (isAdded()) {
                Rect r = new Rect();
                activityRootView.getWindowVisibleDisplayFrame(r);
                int heightDiff = activityRootView.getRootView().getHeight() - (r.bottom - r.top);
                isOpened = heightDiff>firstHeightDiff+100;
                if (isAdded())
                    if(isOpened) {
                        //TODO stuff for when it is up
                    } else {
                        //TODO stuf for when it is down
                    }
            }
        }
    });
}