android 使用Intent传递数据之返回结果

我们开发应用时，不仅仅需要传递数据给其他activity，也要从其他activity中返回数据。

返回数据，我们一般采用Intent对象的方式来返回数据，采用这种方式，需要使用startActivityForResult方法来显式Activity，并且需要重写onActivityResult方法。

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;import android.widget.EditText;public class MainActivity extends Activity {private final int REQUESTCODE=1;//返回的结果码private EditText one,two,three;private Button button;    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);                button = (Button)findViewById(R.id.button);        one = (EditText)findViewById(R.id.one);        two = (EditText)findViewById(R.id.two);        three=(EditText)findViewById(R.id.three);                                button.setOnClickListener(new OnClickListener() {public void onClick(View v) {// TODO Auto-generated method stubint a = Integer.parseInt(one.getText().toString());int b = Integer.parseInt(two.getText().toString());Intent intent = new Intent(MainActivity.this,OtherActivity.class);intent.putExtra("a", a);intent.putExtra("b", b);startActivityForResult(intent, REQUESTCODE);//表示可以返回结果}});            }        @Override    protected void onActivityResult(int requestCode, int resultCode, Intent data) {    // TODO Auto-generated method stub    super.onActivityResult(requestCode, resultCode, data);        if(resultCode==2){    if(requestCode==REQUESTCODE){    int request = data.getIntExtra("three", 0);//接收返回数据    three.setText(String.valueOf(request));    }    }        }    }

启动intent时，使用startActivityForResult方法重写onActivityResult方法

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;import android.widget.TextView;public class OtherActivity extends Activity {private Button button;private TextView textview;private EditText edittext;@Overrideprotected void onCreate(Bundle savedInstanceState) {// TODO Auto-generated method stubsuper.onCreate(savedInstanceState);setContentView(R.layout.other);button = (Button)findViewById(R.id.obutton);textview = (TextView)findViewById(R.id.msg);edittext = (EditText)findViewById(R.id.result);Intent intent = getIntent();int a = intent.getIntExtra("a", 0);int b = intent.getIntExtra("b", 0);textview.setText(a+" + "+b+" =   ?");button.setOnClickListener(new OnClickListener() {public void onClick(View v) {// TODO Auto-generated method stubint request = Integer.parseInt(edittext.getText().toString());Intent intent = new Intent();intent.putExtra("three", request);//通过Intent对象返回结果，调用setResult方法setResult(2,intent);finish();//结束当前的activity的生命周期}});}}

/在另外一个activity中声明一个新的intent的，调用intent对象的setResult方法，并调用finish方法结束activity的生命周期。

更多相关文章

随机推荐