89、Android EditText 悬浮停靠

 1 package com.willen.topFloatDemo;
 2 
 3 import android.content.Context;
 4 import android.os.Handler;
 5 import android.util.AttributeSet;
 6 import android.view.MotionEvent;
 7 import android.widget.ScrollView;
 8 
 9 /*
10  * ScrollView并没有实现滚动监听，所以我们必须自行实现对ScrollView的监听，
11  * 我们很自然的想到在onTouchEvent()方法中实现对滚动Y轴进行监听
12  * ScrollView的滚动Y值进行监听
13  */
14 public class MyScrollView extends ScrollView {
15     
16     private OnScrollListener onScrollListener;  
17     /** 
18      * 主要是用在用户手指离开MyScrollView，MyScrollView
19      * 还在继续滑动，我们用来保存Y的距离，然后做比较 
20      */  
21     private int lastScrollY;
22     
23     public MyScrollView(Context context) {
24         super(context, null);
25     }
26     public MyScrollView(Context context, AttributeSet attrs) {
27         super(context, attrs, 0);
28     }
29     public MyScrollView(Context context, AttributeSet attrs, int defStyle) {
30         super(context, attrs, defStyle);
31     }
32     
33     /** 
34      * 设置滚动接口 
35      * @param onScrollListener 
36      */
37     public void setOnScrollListener(OnScrollListener onScrollListener){
38         this.onScrollListener = onScrollListener;
39     }
40     /** 
41      * 用于用户手指离开MyScrollView的时候获取MyScrollView滚动的Y距离，然后回调给onScroll方法中 
42      */  
43     private Handler handler = new Handler() {  
44         public void handleMessage(android.os.Message msg) {  
45             int scrollY = MyScrollView.this.getScrollY();  
46             //此时的距离和记录下的距离不相等，在隔5毫秒给handler发送消息  
47             if(lastScrollY != scrollY){  
48                 lastScrollY = scrollY;  
49                 handler.sendMessageDelayed(handler.obtainMessage(), 5);    
50             }  
51             if(onScrollListener != null){  
52                 onScrollListener.onScroll(scrollY);  
53             }  
54         };  
55     }; 
56     
57     /** 
58      * 重写onTouchEvent， 当用户的手在MyScrollView上面的时候， 
59      * 直接将MyScrollView滑动的Y方向距离回调给onScroll方法中，当用户抬起手的时候， 
60      * MyScrollView可能还在滑动，所以当用户抬起手我们隔5毫秒给handler发送消息，在handler处理 
61      * MyScrollView滑动的距离 
62      */ 
63     @Override
64     public boolean onTouchEvent(MotionEvent ev) {
65         if(onScrollListener != null){  
66             onScrollListener.onScroll(lastScrollY = this.getScrollY());  
67         }  
68         switch(ev.getAction()){  
69         case MotionEvent.ACTION_UP:  
70              handler.sendMessageDelayed(handler.obtainMessage(), 20);    
71             break;  
72         }  
73         return super.onTouchEvent(ev);
74     }
75 
76     /** 
77      * 滚动的回调接口 
78      */  
79     public interface OnScrollListener{  
80         // 回调方法， 返回MyScrollView滑动的Y方向距离   
81         public void onScroll(int scrollY);  
82     }
83 }

package com.willen.topFloatDemo;

import android.app.Activity;
import android.os.Bundle;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import com.willen.topFloatDemo.MyScrollView.OnScrollListener;

public class MainActivity extends Activity implements OnScrollListener{
    private EditText search_edit;
    private MyScrollView myScrollView;
    private int searchLayoutTop;
    
    LinearLayout search01,search02;
    RelativeLayout rlayout;
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        
        setContentView(R.layout.activity_main);
        
        init();
    }

    private void init() {
        search_edit = (EditText)findViewById(R.id.search_edit);
        myScrollView = (MyScrollView)findViewById(R.id.myScrollView);
        search01 = (LinearLayout)findViewById(R.id.search01);
        search02 = (LinearLayout)findViewById(R.id.search02);
        rlayout = (RelativeLayout)findViewById(R.id.rlayout);
        myScrollView.setOnScrollListener(this);  
    }

    @Override
    public void onWindowFocusChanged(boolean hasFocus) {
        super.onWindowFocusChanged(hasFocus);    
        if(hasFocus){  
            searchLayoutTop = rlayout.getBottom();//鑾峰彇searchLayout鐨勯《閮ㄤ綅缃�
        }
    }

    //鐩戝惉婊氬姩Y鍊煎彉鍖栵紝閫氳繃addView鍜宺emoveView鏉ュ疄鐜版偓鍋滄晥鏋�
    @Override
    public void onScroll(int scrollY) {
        if(scrollY >= searchLayoutTop){  
            if (search_edit.getParent()!=search01) {
                search02.removeView(search_edit);
                search01.addView(search_edit);
            }
        }else{
            if (search_edit.getParent()!=search02) {
                search01.removeView(search_edit);
                search02.addView(search_edit);
            }
        }
    }
}