Activity组件(传递数据)

（一）

1.效果图：点击按钮“调用第二个Activity”，转到第二页面，之后点击“返回数据”，将第二个页面的数据传到第一个页面

activity_main.xml

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3     xmlns:tools="http://schemas.android.com/tools"
 4     android:layout_width="match_parent"
 5     android:layout_height="match_parent"
 6     android:paddingBottom="@dimen/activity_vertical_margin"
 7     android:paddingLeft="@dimen/activity_horizontal_margin"
 8     android:paddingRight="@dimen/activity_horizontal_margin"
 9     android:paddingTop="@dimen/activity_vertical_margin"
10     tools:context="com.example.app4.MainActivity"
11     android:orientation="vertical">
12 
13     <Button
14         android:id="@+id/btn_start"
15         android:text=" 调用第二个Activity"
16         android:layout_width="match_parent"
17         android:layout_height="wrap_content" />
18     <TextView
19         android:id="@+id/tv_show"
20         android:textSize="40dp"
21         android:layout_width="wrap_content"
22         android:layout_height="wrap_content"
23         />
24 </LinearLayout>

slayout.xml

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3     android:layout_width="match_parent"
 4     android:layout_height="match_parent"
 5     android:orientation="vertical">
 6     <Button
 7         android:id="@+id/btn_back"
 8         android:text="返回数据"
 9         android:layout_width="match_parent"
10         android:layout_height="wrap_content" />
11 
12 </LinearLayout>

MianActivty.java

 1 package com.example.app4;
 2 
 3 import android.content.Intent;
 4 import android.support.v7.app.AppCompatActivity;
 5 import android.os.Bundle;
 6 import android.view.View;
 7 import android.widget.Button;
 8 import android.widget.TextView;
 9 
10 public class MainActivity extends AppCompatActivity {
11     private Button button;
12     private TextView textView;
13     private Intent intent;
14 
15     @Override
16     protected void onCreate(Bundle savedInstanceState) {
17         super.onCreate(savedInstanceState);
18         setContentView(R.layout.activity_main);
19         button = (Button)findViewById(R.id.btn_start);
20         textView = (TextView)findViewById(R.id.tv_show);
21 
22         button.setOnClickListener(new View.OnClickListener() {
23             @Override
24             public void onClick(View v) {
25                 intent = new Intent(MainActivity.this,SActivity.class);
26                 startActivityForResult(intent,0);
27             }
28         });
29     }
30 
31     @Override
32     protected void onActivityResult(int requestCode, int resultCode, Intent data) {
33         super.onActivityResult(requestCode, resultCode, data);
34         if (requestCode==0&&resultCode==0){
35             String info = data.getStringExtra("info");
36             textView.setText(info);
37         }
38     }
39 }

SActivty.java

package com.example.app4;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;

/**
 * Created by Administrator on 2018/5/23.
 */
public class SActivity extends Activity {
    private Button button;
    private String content ="你好，我是从SActivity传递回来的数据";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.slayout);
        button=(Button)findViewById(R.id.btn_back);


        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent data = new Intent();
                data.putExtra("info",content);
                setResult(0,data);

                finish();
            }
        });
    }
}