Intent 意图 用于Activity之间的数据传递

用于Activity之间的数据传递
    在起始Activity中，发送数据
      protected void onCreate(Bundle saveInstanceState){
          super.onCreate(saveInstanceState);
          setContentView(R.layout.thisactivity);
          Intent intent = new Intent();
          //设置起始Activity和目标Activity,表示数据从这个Activity传到下个Activity
          intent.setClass(ThisActivity.this,TargetActivity.class);
          //绑定数据
          intent.putExtra("username",username);//也可以绑定数组
          intent.putExtra("userpass",userpass);
          //打开目标Activity
          startActivity(intent);
      }
    在目标Activity中，接收数据：
      protected void onCreate(Bundle saveInstanceState){
          super.onCreate(saveInstanceState);
          setContentView(R.layout.targetactivity);     
          //获得意图
          Intent intent = getIntent();
          //读取数据
          String name = intent.getStringExtra("username");
          String pass = intent.getStringExtra("userpass);
      }
也可以适用Bundle（捆）
    在起始Activity中，发送数据：
      protected void onCreate(Bundle saveInstanceState){
          super.onCreate(saveInstanceState);
          setContentView(R.layout.thisactivity);     
          Intent intent = new Intent();
          //设置起始Activity和目标Activity,表示数据从这个Activity传到下个Activity
          intent.setClass(ThisActivity.this,TargetActivity.class);
          //一次绑定多个数据
          Bundle bundle = new Bundle();
          bundle.putString("username",username);
          bundle.putString("userpass",userpass);
          intent.putExtras(bundle);
          //打开目标Activity
          startActivity(intent);
      }
    在目标Activity中，接收数据：
      protected void onCreate(Bundle saveInstanceState){
          super.onCreate(saveInstanceState);
          setContentView(R.layout.targetactivity);     
          //获得意图
          Intent intent = getIntent();
          //读取数据
          Bundle bundle = intent.getExtras();
          String name = bundle.getString("username");
          String pass = bundle.getString("userpass");
      }
当需要从目标Activity回传数据到原Activity时，可以使用上述方法定义一个新的Intent来传递数据，也可以使用startActivityForResult(Intent intent, int requestCode);方法。
    在起始Activity中，发送数据：
      protected void onCreate(Bundle saveInstanceState){
          super.onCreate(saveInstanceState);
          setContentView(R.layout.thisactivity);     
          Intent intent = new Intent();
          //设置起始Activity和目标Activity,表示数据从这个Activity传到下个Activity
          intent.setClass(ThisActivity.this,TargetActivity.class);
          //绑定数据
          intent.putExtra("username",username);//也可以绑定数组
          intent.putExtra("userpass",userpass);
          //打开目标Activity
          startActivityForResult(intent,1);
      }
      //需要重写onActivityResult方法
      protected void onActivityResult(int requestCode, int resultCode, Intent intent){
         super.onActivityResult(requestCode,resultCode,intent);
         //判断结果码是否与回传的结果码相同
         if(resultCode == 1){
            //获取回传数据
            String name = intent.getStringExtra("name");
            String pass = intent.getStringExtra("pass);
            //对数据进行操作
            ......
         }
    在目标Activity中，接收数据：
      protected void onCreate(Bundle saveInstanceState){
          super.onCreate(saveInstanceState);
          setContentView(R.layout.targetactivity);     
          //获得意图
          Intent intent = getIntent();
          //读取数据
          String name = intent.getStringExtra("username");
          String pass = intent.getStringExtra("userpass);
          //从EditText中获取新的数据给name和pass
          name = editText1.getText().toString();
          pass = editText2.getText().toString()
          //数据发生改变，需要把改变后的值传递回原来的Activity
          intent.putExtra("name",name);
          intent.putExtra("pass",pass);
          //setResult(int resultCode,Intent intent)方法
          setResult(1,intent);
          //销毁此Activity，摧毁此Activity后将自动回到上一个Activity
          finish();
      }

下面是转载来的其他的一些Intent用法实例（转自javaeye）

显示网页
   1. Uri uri = Uri.parse("http://google.com");  
   2. Intent it = new Intent(Intent.ACTION_VIEW, uri);  
   3. startActivity(it);

显示地图
   1. Uri uri = Uri.parse("geo:38.899533,-77.036476");  
   2. Intent it = new Intent(Intent.ACTION_VIEW, uri);   
   3. startActivity(it);   
   4. //其他 geo URI 範例  
   5. //geo:latitude,longitude  
   6. //geo:latitude,longitude?z=zoom  
   7. //geo:0,0?q=my+street+address  
   8. //geo:0,0?q=business+near+city  
   9. //google.streetview:cbll=lat,lng&cbp=1,yaw,,pitch,zoom&mz=mapZoom

路径规划
   1. Uri uri = Uri.parse("http://maps.google.com/maps?f=d&saddr=startLat%20startLng&daddr=endLat%20endLng&hl=en");  
   2. Intent it = new Intent(Intent.ACTION_VIEW, uri);  
   3. startActivity(it);  
   4. //where startLat, startLng, endLat, endLng are a long with 6 decimals like: 50.123456 

打电话
   1. //叫出拨号程序 
   2. Uri uri = Uri.parse("tel:0800000123");  
   3. Intent it = new Intent(Intent.ACTION_DIAL, uri);  
   4. startActivity(it);  
   1. //直接打电话出去  
   2. Uri uri = Uri.parse("tel:0800000123");  
   3. Intent it = new Intent(Intent.ACTION_CALL, uri);  
   4. startActivity(it);  
   5. //用這個，要在 AndroidManifest.xml 中，加上  
   6. //<uses-permission id="android.permission.CALL_PHONE" /> 

传送SMS/MMS
   1. //调用短信程序 
   2. Intent it = new Intent(Intent.ACTION_VIEW, uri);  
   3. it.putExtra("sms_body", "The SMS text");   
   4. it.setType("vnd.android-dir/mms-sms");  
   5. startActivity(it); 
   1. //传送消息 
   2. Uri uri = Uri.parse("smsto://0800000123");  
   3. Intent it = new Intent(Intent.ACTION_SENDTO, uri);  
   4. it.putExtra("sms_body", "The SMS text");  
   5. startActivity(it); 
   1. //传送 MMS  
   2. Uri uri = Uri.parse("content://media/external/images/media/23");  
   3. Intent it = new Intent(Intent.ACTION_SEND);   
   4. it.putExtra("sms_body", "some text");   
   5. it.putExtra(Intent.EXTRA_STREAM, uri);  
   6. it.setType("image/png");   
   7. startActivity(it); 

传送 Email
   1. Uri uri = Uri.parse("mailto:xxx@abc.com");  
   2. Intent it = new Intent(Intent.ACTION_SENDTO, uri);  
   3. startActivity(it); 


   1. Intent it = new Intent(Intent.ACTION_SEND);  
   2. it.putExtra(Intent.EXTRA_EMAIL, "me@abc.com");  
   3. it.putExtra(Intent.EXTRA_TEXT, "The email body text");  
   4. it.setType("text/plain");  
   5. startActivity(Intent.createChooser(it, "Choose Email Client")); 


   1. Intent it=new Intent(Intent.ACTION_SEND);    
   2. String[] tos={"me@abc.com"};    
   3. String[] ccs={"you@abc.com"};    
   4. it.putExtra(Intent.EXTRA_EMAIL, tos);    
   5. it.putExtra(Intent.EXTRA_CC, ccs);    
   6. it.putExtra(Intent.EXTRA_TEXT, "The email body text");    
   7. it.putExtra(Intent.EXTRA_SUBJECT, "The email subject text");    
   8. it.setType("message/rfc822");    
   9. startActivity(Intent.createChooser(it, "Choose Email Client"));


   1. //传送附件
   2. Intent it = new Intent(Intent.ACTION_SEND);  
   3. it.putExtra(Intent.EXTRA_SUBJECT, "The email subject text");  
   4. it.putExtra(Intent.EXTRA_STREAM, "file:///sdcard/mysong.mp3");  
   5. sendIntent.setType("audio/mp3");  
   6. startActivity(Intent.createChooser(it, "Choose Email Client"));

播放多媒体
       Uri uri = Uri.parse("file:///sdcard/song.mp3");  
       Intent it = new Intent(Intent.ACTION_VIEW, uri);  
       it.setType("audio/mp3");  
       startActivity(it); 
       Uri uri = Uri.withAppendedPath(MediaStore.Audio.Media.INTERNAL_CONTENT_URI, "1");  
       Intent it = new Intent(Intent.ACTION_VIEW, uri);  
       startActivity(it);

Market 相关
1.        //寻找某个应用 
2.        Uri uri = Uri.parse("market://search?q=pname:pkg_name"); 
3.        Intent it = new Intent(Intent.ACTION_VIEW, uri);  
4.        startActivity(it);  
5.        //where pkg_name is the full package path for an application 
1.        //显示某个应用的相关信息 
2.        Uri uri = Uri.parse("market://details?id=app_id");  
3.        Intent it = new Intent(Intent.ACTION_VIEW, uri); 
4.        startActivity(it);  
5.        //where app_id is the application ID, find the ID   
6.        //by clicking on your application on Market home   
7.        //page, and notice the ID from the address bar

Uninstall 应用程序
1.        Uri uri = Uri.fromParts("package", strPackageName, null); 
2.        Intent it = new Intent(Intent.ACTION_DELETE, uri);   
3.        startActivity(it);