两个Activity之间的交互startActivityForResult的使用

代码如下：

 1 package com.zzw.teststartintentforrequest;
 2 
 3 import android.app.Activity;
 4 import android.content.Intent;
 5 import android.os.Bundle;
 6 import android.util.Log;
 7 import android.view.View;
 8 import android.view.View.OnClickListener;
 9 import android.widget.TextView;
10 
11 public class MainActivity extends Activity {
12 
13     private final int REQUESTCODE_MAIN = 1;
14 
15     private final String KEY_MAIN = "key_main";
16     private final String KEY_B = "key_b";
17 
18     private TextView textView;
19 
20     @Override
21     protected void onCreate(Bundle savedInstanceState) {
22         super.onCreate(savedInstanceState);
23         setContentView(R.layout.activity_main);
24 
25         textView = (TextView) findViewById(R.id.textView_main);
26 
27         findViewById(R.id.button_main).setOnClickListener(new OnClickListener() {
28 
29             @Override
30             public void onClick(View v) {
31                 Intent intent = new Intent(MainActivity.this, ActivityB.class);
32                 int a=(int) (Math.random()*100);
33                 int b=(int) (Math.random()*100);
34                 int[] nums = { a, b };
35                 intent.putExtra(KEY_MAIN, nums);
36                 startActivityForResult(intent, REQUESTCODE_MAIN);
37             }
38         });
39     }
40 
41     @Override
42     protected void onActivityResult(int requestCode, int resultCode, Intent data) {
43         if(data!=null){
44             Log.d("-------", "requestCode:"+requestCode+"   resultCode:"+resultCode);
45             textView.setText(data.getIntExtra(KEY_B, 0)+"");
46         }
47     }
48 }

MainActivity.java

 1 package com.zzw.teststartintentforrequest;
 2 
 3 import android.app.Activity;
 4 import android.content.Intent;
 5 import android.os.Bundle;
 6 import android.view.View;
 7 import android.view.View.OnClickListener;
 8 import android.widget.TextView;
 9 
10 public class ActivityB extends Activity {
11     
12     private final int RESULTCODE_B=2;
13     
14     private final String KEY_MAIN="key_main";
15     private final String KEY_B="key_b";
16     
17     private TextView textView;
18     
19     
20     @Override
21     protected void onCreate(Bundle savedInstanceState) {
22         super.onCreate(savedInstanceState);
23         setContentView(R.layout.activityb);
24         
25         textView=(TextView) findViewById(R.id.textView_B);
26         
27         int nums[]=this.getIntent().getIntArrayExtra(KEY_MAIN);
28         
29         final int sum=nums[0]+nums[1];
30         
31         textView.setText(nums[0]+"+"+nums[1]+"="+sum);
32         
33         findViewById(R.id.button_B).setOnClickListener(new OnClickListener() {
34             
35             @Override
36             public void onClick(View v) {
37                 Intent intent=new Intent(ActivityB.this,MainActivity.class);
38                 intent.putExtra(KEY_B,sum);
39                 ActivityB.this.setResult(RESULTCODE_B, intent);
40                 ActivityB.this.finish();
41             }
42         });
43     }
44     
45     
46 }

ActivityB.java

 1 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 2     xmlns:tools="http://schemas.android.com/tools"
 3     android:layout_width="match_parent"
 4     android:layout_height="match_parent"
 5     android:background="@android:color/holo_blue_light"
 6     tools:context="com.zzw.teststartintentforrequest.MainActivity" >
 7 
 8     <TextView
 9         android:id="@+id/textView_main"
10         android:layout_width="wrap_content"
11         android:layout_height="wrap_content"
12         android:layout_centerInParent="true"
13         android:text="0"
14         android:textColor="@android:color/holo_red_light"
15         android:textSize="30sp" />
16 
17     <Button
18         android:id="@+id/button_main"
19         android:layout_width="wrap_content"
20         android:layout_height="wrap_content"
21         android:layout_alignParentBottom="true"
22         android:layout_centerHorizontal="true"
23         android:layout_marginBottom="38dp"
24         android:background="@android:color/holo_blue_light"
25         android:text="点击跳转AcyivityB"
26         android:textColor="@android:color/holo_red_light" />
27 
28 </RelativeLayout>

activity_main.xml

 1 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 2     xmlns:tools="http://schemas.android.com/tools"
 3     android:layout_width="match_parent"
 4     android:layout_height="match_parent"
 5     android:background="@android:color/black"
 6     tools:context="com.zzw.teststartintentforrequest.MainActivity" >
 7 
 8     <TextView
 9         android:id="@+id/textView_B"
10         android:layout_width="wrap_content"
11         android:layout_height="wrap_content"
12         android:layout_centerInParent="true"
13         android:textColor="@android:color/white"
14         android:textSize="30sp" />
15 
16     <Button
17         android:id="@+id/button_B"
18         android:layout_width="wrap_content"
19         android:layout_height="wrap_content"
20         android:textColor="@android:color/white"
21         android:background="@android:color/black"
22         android:layout_alignParentBottom="true"
23         android:layout_centerHorizontal="true"
24         android:layout_marginBottom="38dp"
25         android:text="点击返回MainAcyivity" />
26 
27 </RelativeLayout>

activityb.xml