关于Android中软键盘显示隐藏的监听判断总结-白红宇

前言

很多时候我们需要知道软键盘是否打开和关闭，从而处理一些需求。之前在做shou app的时候，由于交互比较复杂，需要知道软键盘是开启或者关闭，决定是否让视频全屏，还是让聊天室全屏，或者是正常显示(上面是视频，下面是聊天室)

ViewTreeObserver.OnGlobalLayoutListener

OnGlobalLayoutListener 是ViewTreeObserver的内部类，当一个视图树的布局发生改变时，可以被ViewTreeObserver监听到，这是一个注册监听视图树的观察者(observer)，在视图树的全局事件改变时得到通知。ViewTreeObserver不能直接实例化，而是通过getViewTreeObserver()获得。以上是说明，摘抄自http://www.cnblogs.com/superle/p/4567400.html这篇文章，也就是说，通过这个api，我们可以知道view的布局状态变化

如何监听软键盘

github上有这样的一个轮子，测试了下，的确有效，思路是，对android.R.id.content所对应的view设置监听，监听它的高度变化，计算比较，来确定软件盘是否弹起或者收拢了。这种模式需要设置activity

full screen模式下如何监听软件盘

在full screen 状态上，发现，以上的方案完全不起作用了。在https://pspdfkit.com/blog/2016/keyboard-handling-on-android/ 上找到了解决办法。大致上说的是full screen模式下，adjustResize不会生效了，window不会resize的。 getWindowVisibleDisplayFrame(Rect)这个api可以获取到view所在的区域，通过它比较每次区域的变化，可以实现监听软键盘是否可见完整代码为:

public class KeyBoardChangeListener implements ViewTreeObserver.OnGlobalLayoutListener {    private static final String TAG = "KeyBoardChangeListener";    // Threshold for minimal keyboard height.    final int MIN_KEYBOARD_HEIGHT_PX = 150;    private final Rect windowVisibleDisplayFrame = new Rect();    // Top-level window decor view.    private View decorView;    private int lastVisibleDecorViewHeight;    private KeyBoardListener keyBoardListener;    KeyBoardChangeListener(Activity activity) {        if (activity == null) {            Log.e(TAG, "activity is null");            return;        }        decorView = activity.getWindow().getDecorView();        decorView.getViewTreeObserver().addOnGlobalLayoutListener(this);    }    public void setKeyBoardListener(KeyBoardListener keyBoardListener) {        this.keyBoardListener = keyBoardListener;    }    @Override    public void onGlobalLayout() {        // Retrieve visible rectangle inside window.        decorView.getWindowVisibleDisplayFrame(windowVisibleDisplayFrame);        final int visibleDecorViewHeight = windowVisibleDisplayFrame.height();        // Decide whether keyboard is visible from changing decor view height.        if (lastVisibleDecorViewHeight != 0) {            if (lastVisibleDecorViewHeight > visibleDecorViewHeight + MIN_KEYBOARD_HEIGHT_PX) {                // Calculate current keyboard height (this includes also navigation bar height when in fullscreen mode).                int currentKeyboardHeight = decorView.getHeight() - windowVisibleDisplayFrame.bottom;                // Notify listener about keyboard being shown.                if (keyBoardListener != null) {                    keyBoardListener.onKeyboardChange(true, currentKeyboardHeight);                }            } else if (lastVisibleDecorViewHeight + MIN_KEYBOARD_HEIGHT_PX < visibleDecorViewHeight) {                // Notify listener about keyboard being hidden.                if (keyBoardListener != null) {                    keyBoardListener.onKeyboardChange(false, 0);                }            }        }        // Save current decor view height for the next call.        lastVisibleDecorViewHeight = visibleDecorViewHeight;    }    public interface KeyBoardListener {        /**         * call back         *         * @param isShow         true is show else hidden         * @param keyboardHeight keyboard height         */        void onKeyboardChange(boolean isShow, int keyboardHeight);    }}复制代码

前言

ViewTreeObserver.OnGlobalLayoutListener

如何监听软键盘

full screen模式下如何监听软件盘

相关参考