开启新的activity获取它的返回值

1、开始界面

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity" >

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        >
        <EditText
            android:id="@+id/et_number"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:hint="请输入联系人" />
        <Button
            android:onClick="click"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="联系人"
            />
    </LinearLayout>
     <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        >
        <EditText
            android:id="@+id/et_number2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:hint="请输入联系人" />
        <Button
            android:onClick="click2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="联系人2"
            />
    </LinearLayout>

</LinearLayout>

2、开启新的activity代码

 package com.example.smssender;

 import android.os.Bundle;
 import android.app.Activity;
 import android.content.Intent;
 import android.view.Menu;
 import android.view.View;
 import android.widget.EditText;

 public class MainActivity extends Activity {

     private EditText et_number;
     private EditText et_number2;
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
         et_number = (EditText) findViewById(R.id.et_number);
         et_number2 = (EditText) findViewById(R.id.et_number2);
     }

     public void click(View view){
         Intent intent = new Intent(this, ContactActivity.class);
         //startActivity(intent);
         //请求码的作用是区别是谁发起的请求
         startActivityForResult(intent, 1);
     }

     public void click2(View view){
         Intent intent = new Intent(this, ContactActivity.class);
         //startActivity(intent);
         //请求码的作用是区别是谁发起的请求
         startActivityForResult(intent, 2);
     }

     @Override
     protected void onActivityResult(int requestCode, int resultCode, Intent data) {
         // TODO Auto-generated method stub
         super.onActivityResult(requestCode, resultCode, data);
         if(data != null){
             String number = data.getStringExtra("number");
             if(requestCode == 1){
                 et_number.setText(number);
             }else{
                 et_number2.setText(number);
             }
         }
     }

 }

3、获取联系人

1)清单文件

　　<uses-permission android:name="android.permission.READ_CONTACTS"/>//权限

2)通过内容提供者获取联系人

 package com.example.smssender;

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

 import android.content.ContentResolver;
 import android.content.Context;
 import android.database.Cursor;
 import android.net.Uri;

 public class ContactService {
     public static List<contactInfo> getContactAll(Context context){
         List<contactInfo> infos = new ArrayList<contactInfo>();
         //通过内容提供者获取联系人
         ContentResolver resolver = context.getContentResolver();
         Uri uri = Uri.parse("content://com.android.contacts/raw_contacts");
         Uri dataUri = Uri.parse("content://com.android.contacts/data");
         Cursor cursor = resolver.query(uri, null, null, null, null);
         while(cursor.moveToNext()){
             String id = cursor.getString(cursor.getColumnIndex("contact_id"));
             Cursor datacursor = resolver.query(dataUri, null, "raw_contact_id=?", new String[]{id}, null);
             contactInfo info = new contactInfo();
             while(datacursor.moveToNext()){
                 String data1 = datacursor.getString(datacursor.getColumnIndex("data1"));
                 String mimetype = datacursor.getString(datacursor.getColumnIndex("mimetype"));
                 if("vnd.android.cursor.item/name".equals(mimetype)){
                     info.setUsername(data1);
                 }else if("vnd.android.cursor.item/phone_v2".equals(mimetype)){
                     info.setNumber(data1);
                 }
             }

             infos.add(info);

         }
         return infos;
     }
 }

4、设置联系人进Listview

 <?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" >

     <ListView
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         android:id="@+id/lv_contact"
         ></ListView>

 </LinearLayout>

 <?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" >

     <TextView
         android:id="@+id/et_username"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         />
     <TextView
         android:id="@+id/et_number"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         />

 </LinearLayout>

java代码:

 package com.example.smssender;

 import java.util.List;

 import android.app.Activity;
 import android.content.ContentResolver;
 import android.content.Intent;
 import android.database.Cursor;
 import android.net.Uri;
 import android.os.Bundle;
 import android.view.View;
 import android.view.ViewGroup;
 import android.widget.AdapterView;
 import android.widget.AdapterView.OnItemClickListener;
 import android.widget.BaseAdapter;
 import android.widget.ListView;
 import android.widget.TextView;

 public class ContactActivity extends Activity {

     private ListView lv_contact;
     private List<contactInfo> infos = null;
     @Override
     protected void onCreate(Bundle savedInstanceState) {

         // TODO Auto-generated method stub
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_contact);

         infos = ContactService.getContactAll(this);

         lv_contact = (ListView)findViewById(R.id.lv_contact);
         lv_contact.setAdapter(new ContactAdapter());

         lv_contact.setOnItemClickListener(new OnItemClickListener() {

             @Override
             public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
                     long arg3) {
                 // TODO Auto-generated method stub
                 contactInfo info = infos.get(arg2);
                 String number = info.getNumber();
                 Intent data = new Intent();
                 data.putExtra("number", number);
                 setResult(0, data);//0是结果码，可以在onActivityResult重新获取
                 //关闭当前activity,把数据传回给它的激活者
                 finish();

             }

         });
     }

     private class ContactAdapter extends BaseAdapter{

         @Override
         public int getCount() {
             // TODO Auto-generated method stub
             return infos.size();
         }

         @Override
         public Object getItem(int arg0) {
             // TODO Auto-generated method stub
             return null;
         }

         @Override
         public long getItemId(int arg0) {
             // TODO Auto-generated method stub
             return 0;
         }

         @Override
         public View getView(int arg0, View arg1, ViewGroup arg2) {
             // TODO Auto-generated method stub
             contactInfo info = infos.get(arg0);
             View view = View.inflate(ContactActivity.this, R.layout.contact_item, null);
             TextView et_username = (TextView)view.findViewById(R.id.et_username);
             et_username.setText(info.getUsername());

             TextView et_number = (TextView)view.findViewById(R.id.et_number);
             et_number.setText(info.getNumber());        

             return view;
         }

     }

 }