Android进阶2之Activity之间数据交流(onActivityResult的用法) (转载)

转自:http://blog.csdn.net/sjf0115/article/details/7387467

 

主要功能:

在一个主界面(主Activity)上能连接往许多不同子功能模块(子Activity上去),当子模块的事情做完之后就回到主界面,或许还同时返回一些子模块完成的数据交给主Activity处理。这样的数据交流就要用到回调函数onActivityResult。

<1>startActivityForResult(Intent intent, int requestCode);

第一个参数:一个Intent对象

第二个参数:如果> = 0,当Activity结束时requestCode将归还在onActivityResult()中。以便确定返回的数据是从哪个Activity中返回

<2>onActivityResult(int requestCode, int resultCode, Intent data)

第一个参数:这个整数requestCode提供给onActivityResult,是以便确认返回的数据是从哪个Activity返回的。

            这个requestCode和startActivityForResult中的requestCode相对应。

第二个参数:这整数resultCode是由子Activity通过其setResult()方法返回。


第三个参数:一个Intent对象,带有返回的数据。

<3>setResult(int resultCode, Intent data)

调用这个方法把Activity想要返回的数据返回到父Activity

第一个参数:当Activity结束时resultCode将归还在onActivityResult()中,一般为RESULT_CANCELED , RESULT_OK。

第二个参数:一个Intent对象,返回给父Activity的数据。


 

       

   

 

 

本实例一共有三个Activity。点击飞往火星跳转到otherActivity,把地球带给火星的消息显示在otherActivity中。点击返回地球时把火星带给地球的消息传到主Activity.

同理:

点击飞往月球跳转到thirdActivity,把地球带给月球的消息显示在thirdActivity中。点击返回地球时把月球带给地球的消息传到主Activity.


具体实现:

主Activity:

 

    package xiaosi.onActivityResult;  
      
    import android.app.Activity;  
    import android.content.Intent;  
    import android.os.Bundle;  
    import android.view.View;  
    import android.view.View.OnClickListener;  
    import android.widget.Button;  
    import android.widget.TextView;  
      
    public class OnActivityResultActivity extends Activity  
    {  
        private Button              button  = null;  
        private Button              button1 = null;  
        private TextView            text    = null;  
        private static final int    Mars    = 0;  
        private static final int    Moon    = 1;  
      
        @Override  
        public void onCreate(Bundle savedInstanceState)  
        {  
            super.onCreate(savedInstanceState);  
            setContentView(R.layout.main);  
            text = (TextView) findViewById(R.id.text);  
            button = (Button) findViewById(R.id.button);  
            button.setOnClickListener(new OnClickListener() {  
                @Override  
                public void onClick(View v)  
                {  
                    Intent intent = new Intent(OnActivityResultActivity.this, otherActivity.class);  
                    String content = "地球来的消息:你好,我是来自地球上的小老鼠。我好想去你们的火星呀";  
                    intent.putExtra("FromEarth", content);  
                    startActivityForResult(intent, Mars);  
                }  
            });  
            button1 = (Button) findViewById(R.id.button1);  
            button1.setOnClickListener(new OnClickListener() {  
                @Override  
                public void onClick(View v)  
                {  
                    Intent intent = new Intent(OnActivityResultActivity.this, thirdActivity.class);  
                    String content = "地球来的消息:你好,我是来自地球上的小老鼠。我好想去你们月球";  
                    intent.putExtra("FromEarth", content);  
                    startActivityForResult(intent, Moon);  
                }  
            });  
        }  
      
        @Override  
        protected void onActivityResult(int requestCode, int resultCode, Intent data)  
        {  
            switch (requestCode)  
            {  
            case Mars:  
                Bundle MarsBuddle = data.getExtras();  
                String MarsMessage = MarsBuddle.getString("FromMars");  
                text.setText(MarsMessage);  
                break;  
            case Moon:  
                Bundle MoonBuddle = data.getExtras();  
                String MoonMessage = MoonBuddle.getString("FromMoon");  
                text.setText(MoonMessage);  
                break;  
            }  
        }  
    }  

 

otherActivity:

 

    package xiaosi.onActivityResult;  
      
    import android.app.Activity;  
    import android.content.Intent;  
    import android.os.Bundle;  
    import android.view.View;  
    import android.widget.Button;  
    import android.widget.TextView;  
      
    public class otherActivity extends Activity  
    {  
        private Button  button  = null;  
      
        @Override  
        public void onCreate(Bundle savedInstanceState)  
        {  
            super.onCreate(savedInstanceState);  
            setContentView(R.layout.other);  
            Intent EarthIntent = getIntent();  
            String EarthMessage = EarthIntent.getStringExtra("FromEarth");  
            button = (Button) findViewById(R.id.button);  
            button.setOnClickListener(new View.OnClickListener() {  
                @Override  
                public void onClick(View v)  
                {  
                    Intent intent = new Intent(otherActivity.this, OnActivityResultActivity.class);  
                    String passString = "火星来的消息:Hello,我是火星的Jack,非常高兴你能来火星";  
                    intent.putExtra("FromMars", passString);  
                    setResult(RESULT_OK, intent);  
                    finish();  
                }  
            });  
            TextView textView = (TextView) findViewById(R.id.othertext);  
            textView.setText(EarthMessage);  
        }  
    }  

 

thirdActivity:

 

    package xiaosi.onActivityResult;  
      
    import android.app.Activity;  
    import android.content.Intent;  
    import android.os.Bundle;  
    import android.view.View;  
    import android.widget.Button;  
    import android.widget.TextView;  
      
    public class thirdActivity extends Activity  
    {  
        private Button  button  = null;  
      
        @Override  
        public void onCreate(Bundle savedInstanceState)  
        {  
            super.onCreate(savedInstanceState);  
            setContentView(R.layout.third);  
            Intent EarthIntent = getIntent();  
            String EarthMessage = EarthIntent.getStringExtra("FromEarth");  
            button = (Button) findViewById(R.id.button);  
            button.setOnClickListener(new View.OnClickListener() {  
                @Override  
                public void onClick(View v)  
                {  
                    Intent intent = new Intent(thirdActivity.this, OnActivityResultActivity.class);  
                    String passString = "月球来的消息:Hello,我是月球的Lucy,非常欢迎你来月球";  
                    intent.putExtra("FromMoon", passString);  
                    setResult(RESULT_OK, intent);  
                    finish();  
                }  
            });  
            TextView textView = (TextView) findViewById(R.id.thirdtext);  
            textView.setText(EarthMessage);  
        }  
    }  

 

 

 

 

 

posted on 2015-05-08 12:44  次奥砖家  阅读(242)  评论(0编辑  收藏  举报

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