Android学习小结之获取被启动的Activity传回的数据

public class MainActivity extends AppCompatActivity {
private TextView textView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//找到TextView
textView=(TextView)findViewById(R.id.textView);
findViewById(R.id.btnSend).setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent=new Intent(MainActivity.this,AnotherActivity.class);
startActivityForResult(intent,0);
}
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
textView.setText("另外一个Activity传回来的数据是："+data.getStringExtra("data"));
}
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin"
tools:context="com.example.androidtest.MainActivity">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="启动另一个Activity"
android:id="@+id/btnSend" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="New Text"
android:id="@+id/textView" />
</LinearLayout>

public class AnotherActivity extends AppCompatActivity {
private EditText editText;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_another);
editText= (EditText) findViewById(R.id.editText);
Button button= (Button) findViewById(R.id.btnSendBack);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//返回结果
Intent i=new Intent();
i.putExtra("data",editText.getText().toString());
setResult(1,i);
finish();
}
});
}
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:orientation="vertical"
tools:context="com.example.androidtest.AnotherActivity">
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/editText" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="发送回去"
android:id="@+id/btnSendBack"/>
</LinearLayout> 

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if(requestCode==0){
if(resultCode==1){
textView.setText("另外一个Activity传回来的数据是："+data.getStringExtra("data"));
}
}
}