初学移动开发技术_两个页面相互跳转，并且向上一个活动传递数据并显示

一、实验内容：

     从MainActivity跳转到SecondActivity，当从SecondActivity向MainActivity跳转时，传递并显示数据

二、代码

  （1）MainActivity

package cn.bzu.tong.tiaozhuan;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;

public class MainActivity extends Activity
{

private Button btnClick1;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

btnClick1=(Button) findViewById(R.id.btnClick1);
btnClick1.setOnClickListener(new OnClickListener()
{

public void onClick(View view)
{
Intent intent = new Intent(MainActivity.this,SecondActivity.class) ;
startActivityForResult(intent,1) ;
}
});

}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data)
{
super.onActivityResult(requestCode, resultCode, data);
switch (resultCode)//判断数据来源
{
case 1:
if(reultCode==RESULT_OK){//看数据是否正常返回
String returnData = data.getStringExtra("data_return");
Toast.makeText(this, "returnData="+returnData, Toast.LENGTH_LONG).show();

Log.d("MainActivity", "returnData="+returnData);

}
break;

}

}

@Override
public boolean onCreateOptionsMenu(Menu menu)
{
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}

}

(2)SecondActivity

package cn.bzu.tong.tiaozhuan;

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

public class SecondActivity extends Activity
{

private Button btnClick2;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_second);

btnClick2=(Button) findViewById(R.id.btnClick2);
btnClick2.setOnClickListener(new OnClickListener()
{

@Override
public void onClick(View view)
{
Intent intent=new Intent();

intent.putExtra("data_return","相信自己");
setResult(RESULT_OK,intent);
finish();
}
});
}

@Override
public boolean onCreateOptionsMenu(Menu menu)
{
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.second, menu);
return true;
}

}

三、要实现好向上一活动传递数据并显示，要充分利用好