Android startActivityForResult的使用

在Android中startActivityForResult主要作用就是:

A-Activity需要在B-Activtiy中执行一些数据操作，而B-Activity又要将，执行操作数据的结果返回给A-Activtiy

//看效果

//看代码

package sn.len.actres;

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 ActivityResultDemoActivity extends Activity
{
    private Button button_start_task;
    private TextView TextView_result;
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        button_start_task=(Button) findViewById(R.id.button_start_task);
        TextView_result=(TextView) findViewById(R.id.TextView_result);
        button_start_task.setOnClickListener(new button_start_task_Listener());
    }
    private class button_start_task_Listener implements OnClickListener
    {
        public void onClick(View v)
        {
            Intent intent=new Intent(ActivityResultDemoActivity.this,SimpleTaskActivity.class);
            //关键点来了，使用startActivityForResult来启动
            startActivityForResult(intent, 100);
        }
    }
    /**
     * 复写onActivityResult，这个方法
     * 是要等到SimpleTaskActivity点了提交过后才会执行的
     */
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data)
    {
        //可以根据多个请求代码来作相应的操作
        if(20==resultCode)
        {
            String bookname=data.getExtras().getString("bookname");
            String booksale=data.getExtras().getString("booksale");
            TextView_result.setText("书籍名称:"+bookname+"书籍价钱"+booksale+"元");
        }
        super.onActivityResult(requestCode, resultCode, data);
    }
}

//任务处理类

package sn.len.actres;

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.EditText;

public class SimpleTaskActivity extends Activity
{
    private EditText EditText_bookname;
    private EditText EditText_booksale;
    private Button Button_task_fulfill;

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main2);
        
        EditText_bookname=(EditText) findViewById(R.id.EditText_bookname);
        EditText_booksale=(EditText) findViewById(R.id.EditText_booksale);
        Button_task_fulfill=(Button) findViewById(R.id.Button_task_fulfill);
        Button_task_fulfill.setOnClickListener(new Button_task_fulfill_Listener());
    }
    private class Button_task_fulfill_Listener implements OnClickListener
    {
        public void onClick(View v)
        {
            String str_bookname=EditText_bookname.getText().toString();
            String str_booksale=EditText_booksale.getText().toString();
            
            //判断空，我就不判断了。。。。
            Intent data=new Intent();
            data.putExtra("bookname", str_bookname);
            data.putExtra("booksale", str_booksale);
            //请求代码可以自己设置，这里设置成20
            setResult(20, data);
            //关闭掉这个Activity
            finish();
        }
    }
}