android 键盘监听

从知乎上看到的一种解决方案，目前还没发现有什么坑。

public class SoftKeyBroadManager implements ViewTreeObserver.OnGlobalLayoutListener{
    
    public interface SoftKeyboardStateListener {
        void onSoftKeyboardOpened(int keyboardHeightInPx);
        void onSoftKeyboardClosed();
    }

    private final List<SoftKeyboardStateListener> listeners = new LinkedList<SoftKeyboardStateListener>();
    private final View activityRootView;
    private int lastSoftKeyboardHeightInPx;
    private boolean isSoftKeyboardOpened;

    public SoftKeyBroadManager(View activityRootView) {
        this(activityRootView,false);
    }

    public SoftKeyBroadManager(View activityRootView, boolean isSoftKeyboardOpened) {
        this.activityRootView = activityRootView;
        this.isSoftKeyboardOpened = isSoftKeyboardOpened;
        activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(this);
    }

    @Override
    public void onGlobalLayout() {
        final Rect r = new Rect();
        activityRootView.getWindowVisibleDisplayFrame(r);

        final int heightDiff = activityRootView.getRootView().getHeight() - (r.bottom - r.top);
       
        if (!isSoftKeyboardOpened && heightDiff > 500) { 
            // 如果高度超过500 键盘可能被打开
            isSoftKeyboardOpened = true;
            notifyOnSoftKeyboardOpened(heightDiff);
        } else if (isSoftKeyboardOpened && heightDiff < 500) {
            isSoftKeyboardOpened = false;
            notifyOnSoftKeyboardClosed();
        }
    }

    public void setIsSoftKeyboardOpened(boolean isSoftKeyboardOpened) {
        this.isSoftKeyboardOpened = isSoftKeyboardOpened;
    }

    public boolean isSoftKeyboardOpened() {
        return isSoftKeyboardOpened;
    }

  
    public int getLastSoftKeyboardHeightInPx() {
        return lastSoftKeyboardHeightInPx;
    }

    public void addSoftKeyboardStateListener(SoftKeyboardStateListener listener) {
        listeners.add(listener);
    }

    public void removeSoftKeyboardStateListener(SoftKeyboardStateListener listener) {
        listeners.remove(listener);
    }

    private void notifyOnSoftKeyboardOpened(int keyboardHeightInPx) {
        this.lastSoftKeyboardHeightInPx = keyboardHeightInPx;

        for (SoftKeyboardStateListener listener : listeners) {
            if (listener != null) {
                listener.onSoftKeyboardOpened(keyboardHeightInPx);
            }
        }
    }

    private void notifyOnSoftKeyboardClosed() {
        for (SoftKeyboardStateListener listener : listeners) {
            if (listener != null) {
                listener.onSoftKeyboardClosed();
            }
        }
    }

}

使用方法

softKeyBroadManager = new SoftKeyBroadManager(root);
    softKeyBroadManager.addSoftKeyboardStateListener(softKeyboardStateListener);

private SoftKeyBroadManager.SoftKeyboardStateListener softKeyboardStateListener = new
            SoftKeyBroadManager.SoftKeyboardStateListener() {


                @Override
                public void onSoftKeyboardOpened(int keyboardHeightInPx) {
                    PandaLogUtils.getInstance().i("键盘打开");

                }

                @Override
                public void onSoftKeyboardClosed() {
                    PandaLogUtils.getInstance().i("键盘关闭");
                    //重新算价
                    calculate();
                }
            };