/**
 * 類描述：鍵盤顯隱監(jiān)聽<br/>
 * 創(chuàng)建人：吳冬冬<br/>
 * 創(chuàng)建時間：2019/8/12 15:26 <br/>
 */
public class KeyBoardListener implements ViewTreeObserver.OnGlobalLayoutListener {

    private final int KEY_BOARD_HEIGHT = IntEKt.dp2px(70);

    public interface OnKeyBoardChangeListener {
        void keyBoardShow();

        void keyBoardHide();
    }

    /**
     * activity 根視圖
     */
    private final View mDecorView;
    /**
     * 根視圖 高度
     */
    private int mDecorViewHeight;

    private OnKeyBoardChangeListener mListener;

    public static KeyBoardListener setListener(AppCompatActivity activity, OnKeyBoardChangeListener listener) {
        KeyBoardListener keyBoardListener = new KeyBoardListener(activity);
        keyBoardListener.setListener(listener);
        return keyBoardListener;
    }

    public void removeListener() {
        mDecorView.getViewTreeObserver().removeOnGlobalLayoutListener(this);
        mListener = null;
    }

    private KeyBoardListener(AppCompatActivity activity) {
        //獲取根視圖
        mDecorView = activity.getWindow().getDecorView();
        //監(jiān)聽視圖種全局布局發(fā)生改變 或者 視圖樹中的某個視圖的可視狀態(tài)發(fā)生改變
        mDecorView.getViewTreeObserver().addOnGlobalLayoutListener(this);
    }

    public void setListener(OnKeyBoardChangeListener listener) {
        mListener = listener;
    }

    @Override
    public void onGlobalLayout() {
        //獲取當(dāng)前根視圖在屏幕上顯示的大小
        Rect rect = new Rect();
        mDecorView.getWindowVisibleDisplayFrame(rect);
        int height = rect.height();
        Logger.d("123===", "當(dāng)前屏幕高度：" + height);
        if (height == 0) {
            mDecorViewHeight = height;
            return;
        }

        //根視圖高度沒有變化鹿寨，可以看作 鍵盤 顯示/隱藏 沒有改變
        if (mDecorViewHeight == height) {
            return;
        }

        //根視圖顯示高度 變小 超過 70dp，看作鍵盤顯示
        if (mDecorViewHeight - height > KEY_BOARD_HEIGHT) {
            mDecorViewHeight = height;
            if (mListener != null) {
                mListener.keyBoardShow();
            }
            return;
        }

        //根視圖顯示高度 變大 超過 70dp匙睹， 看作鍵盤隱藏
        if (height - mDecorViewHeight > KEY_BOARD_HEIGHT) {
            mDecorViewHeight = height;
            if (mListener != null) {
                mListener.keyBoardHide();
            }
            return;
        }
    }
}