Android軟件鍵盤狀態監聽(顯示/隱藏&當前高度)

   //調用

SoftKeyBoardListener.setListener(this,
        new SoftKeyBoardListener.OnSoftKeyBoardChangeListener() {
            @Override
            public void keyBoardShow(int height) {
               
            }

            @Override
            public void keyBoardHide(int height) {
            
            }
        });

import android.app.Activity;
import android.graphics.Rect;
import android.view.View;
import android.view.ViewTreeObserver;

/**
 * Created by AnnisLee
 */
public class SoftKeyBoardListener {
    private View rootView;//activity的根視圖
    int rootViewVisibleHeight;//紀錄根視圖的顯示高度
    private OnSoftKeyBoardChangeListener onSoftKeyBoardChangeListener;

    public SoftKeyBoardListener(Activity activity) {
        //獲取activity的根視圖
        rootView = activity.getWindow().getDecorView();

        //監聽視圖樹中全局佈局發生改變或者視圖樹中的某個視圖的可視狀態發生改變
        rootView.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
            @Override
            public void onGlobalLayout() {
                //獲取當前根視圖在屏幕上顯示的大小
                Rect r = new Rect();
                rootView.getWindowVisibleDisplayFrame(r);
                int visibleHeight = r.height();
                if (rootViewVisibleHeight == 0) {
                    rootViewVisibleHeight = visibleHeight;
                    return;
                }

                //根視圖顯示高度沒有變化，可以看作軟鍵盤顯示／隱藏狀態沒有改變
                if (rootViewVisibleHeight == visibleHeight) {
                    return;
                }

                //根視圖顯示高度變小超過200，可以看作軟鍵盤顯示了
                if (rootViewVisibleHeight - visibleHeight > 200) {
                    if (onSoftKeyBoardChangeListener != null) {
                        onSoftKeyBoardChangeListener.keyBoardShow(rootViewVisibleHeight - visibleHeight);
                    }
                    rootViewVisibleHeight = visibleHeight;
                    return;
                }

                //根視圖顯示高度變大超過200，可以看作軟鍵盤隱藏了
                if (visibleHeight - rootViewVisibleHeight > 200) {
                    if (onSoftKeyBoardChangeListener != null) {
                        onSoftKeyBoardChangeListener.keyBoardHide(visibleHeight - rootViewVisibleHeight);
                    }
                    rootViewVisibleHeight = visibleHeight;
                    return;
                }

            }
        });
    }

    private void setOnSoftKeyBoardChangeListener(OnSoftKeyBoardChangeListener onSoftKeyBoardChangeListener) {
        this.onSoftKeyBoardChangeListener = onSoftKeyBoardChangeListener;
    }

    public interface OnSoftKeyBoardChangeListener {
        void keyBoardShow(int height);

        void keyBoardHide(int height);
    }

    public static void setListener(Activity activity, OnSoftKeyBoardChangeListener onSoftKeyBoardChangeListener) {
        SoftKeyBoardListener softKeyBoardListener = new SoftKeyBoardListener(activity);
        softKeyBoardListener.setOnSoftKeyBoardChangeListener(onSoftKeyBoardChangeListener);
    }
}