重温3 Activity Intent 向下传递数据 向上传递数据

1、使用Intent向下传递数据

Intent intent = new Intent(MainActivity.this,SecongActivity.class);
intent.putExtra("data_from_MainActivity","I am MainActivity");
startActivity(intent);

从SecondActivity取数据

Intent intent = getIntent();
String data = intent.getStringExtra("data_from_MainActivity");

根据传递的数据的类型选择getIntExtra()/getBooleanExtra...

2、向上传递数据

MainActivity.java

Intent intent1 = new Intent("sunny.example.comeonintent.ACTION");
startActivityForResult(intent1,1);

期望返回数据

startActivityForResult()

void android.support.v4.app.FragmentActivity.startActivityForResult(Intent
intent, int requestCode)

SubActivity.java

Intent intent = new Intent();
intent.putExtra("data_from_sub", "I am Sub");
setResult(RESULT_OK,intent);//RESULT_OK -1;RESULT_CANCELED 0;

在MainActivity中接收数据

<span style="white-space:pre">	</span>@Override
protected void onActivityResult(int RequestCode,int ResultCode,Intent data){
TextView tv1 = (TextView)findViewById(R.id.tv1);
TextView tv2 = (TextView)findViewById(R.id.tv2);
switch(RequestCode){
case 1:
if(ResultCode == RESULT_OK){
String returnData1 = data.getStringExtra("data_from_sub");
tv1.setText(returnData1);
}else{}
case 2:
if(ResultCode == RESULT_OK){
String returnData2 = data.getStringExtra("data_from_third");
tv2.setText(returnData2);
}else{

}
default:
}

}

完整代码在：https://github.com/HiSunny/ComeOnIntent.git