手势使用

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1.自定义的ListView

package com.example.test;

import android.content.Context;
import android.util.AttributeSet;
import android.view.GestureDetector;
import android.view.GestureDetector.OnGestureListener;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.ListView;
import android.widget.RelativeLayout;


public class MyListView extends ListView implements OnTouchListener,
OnGestureListener {

private GestureDetector detector;
private int itemPostion;
private boolean isDelete;

public MyListView(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
detector = new GestureDetector(this);
setOnTouchListener(this);
}


@Override
public boolean onTouch(View v, MotionEvent event) {
// TODO Auto-generated method stub
return detector.onTouchEvent(event);
}


@Override
public boolean onDown(MotionEvent e) {
// TODO Auto-generated method stub
if (!isDelete && 
e.getAction() == MotionEvent.ACTION_DOWN) {
itemPostion = pointToPosition((int)e.getX(), (int)e.getY());
}
return false;
}


@Override
public void onShowPress(MotionEvent e) {
// TODO Auto-generated method stub

}


@Override
public boolean onSingleTapUp(MotionEvent e) {
// TODO Auto-generated method stub
return false;
}


@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX,
float distanceY) {
// TODO Auto-generated method stub
return false;
}


@Override
public void onLongPress(MotionEvent e) {
// TODO Auto-generated method stub

}


@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
float velocityY) {
// TODO Auto-generated method stub
if (!isDelete && 
Math.abs(velocityX)>Math.abs(velocityY)) {
ViewGroup viewGroup = (ViewGroup)getChildAt(itemPostion - 
getFirstVisiblePosition());

RelativeLayout.LayoutParams rl = new RelativeLayout.LayoutParams(-2, -2);
rl.addRule(RelativeLayout.ALIGN_PARENT_RIGHT);
Button btn_del = new Button(getContext());
btn_del.setText("删除");
viewGroup.addView(btn_del, rl);
isDelete = true;
}
return false;
}

}

2.XML文件

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="horizontal" >
    
<TextView
   android:id="@+id/tv_item"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:textSize="20sp"/>
</RelativeLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
    
<com.example.test.MyListView
   android:id="@+id/listView"
   android:layout_width="fill_parent"
   android:layout_height="fill_parent"/>
</LinearLayout>

3.Activity代码

package com.example.test;


import java.util.ArrayList;
import java.util.List;


import android.app.Activity;
import android.os.Bundle;
import android.widget.ArrayAdapter;
import android.widget.ListView;


public class MainActivity extends Activity {

ListView listView;

@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.main);

listView = (ListView)findViewById(R.id.listView);
List<String> list = new ArrayList<String>();
for (int i = 0; i < 5; i++) {
list.add("item"+i);
}
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, 
R.layout.item,
R.id.tv_item,
list);
listView.setAdapter(adapter);
}
}