Intent 应该算是Android 中特有的东西。你可以在Intent 中指定程序要执行的动作（比如：view,edit,dial ），以及程序执行到该动作时所需要的资料。都指定好后，只要调用startActivity() ，Android 系统会自动寻找最符合你指定要求的应用程序，并执行该程序。

下面列出几种Intent 的用法
显示网页:

1. Uri uri = Uri.parse("http://www.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);

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);

拨打电话:
调用拨号程序

1. Uri uri = Uri.parse("tel:xxxxxx ");
2. Intent it = new Intent(Intent.ACTION_DIAL, uri);
3. startActivity(it);

1. Uri uri = Uri.parse("tel.xxxxxx");
2. Intent it =new Intent(Intent.ACTION_CALL,uri);
3. 要使用这个必须在配置文件中加入<uses-permission id="android.permission.CALL_PHONE" />

发送SMS/MMS
调用发送短信的程序

1. Intent it = new Intent(Intent.ACTION_VIEW);
2. it.putExtra("sms_body", "The SMS text");
3. it.setType("vnd.android-dir/mms-sms");
4. startActivity(it);

发送短信

1. Uri uri = Uri.parse("smsto:0800000123");
2. Intent it = new Intent(Intent.ACTION_SENDTO, uri);
3. it.putExtra("sms_body", "The SMS text");
4. startActivity(it);

发送彩信

1. Uri uri = Uri.parse("content://media/external/images/media/23");
2. Intent it = new Intent(Intent.ACTION_SEND);
3. it.putExtra("sms_body", "some text");
4. it.putExtra(Intent.EXTRA_STREAM, uri);
5. it.setType("image/png");
6. startActivity(it);

发送Email

2. Uri uri = Uri.parse("mailto:[email protected] ");
3. Intent it = new Intent(Intent.ACTION_SENDTO, uri);
4. startActivity(it);

1. Intent it = new Intent(Intent.ACTION_SEND);
2. it.putExtra(Intent.EXTRA_EMAIL, "[email protected] ");
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={"[email protected] "};
3. String[] ccs={"[email protected] "};
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"));

添加附件

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

播放多媒体

2. Intent it = new Intent(Intent.ACTION_VIEW);
3. Uri uri = Uri.parse("file:///sdcard/song.mp3 ");
4. it.setDataAndType(uri, "audio/mp3");
5. startActivity(it);

1. Uri uri = Uri.withAppendedPath(MediaStore.Audio.Media.INTERNAL_CONTENT_URI, "1");
2. Intent it = new Intent(Intent.ACTION_VIEW, uri);
3. startActivity(it);

Uninstall 程序

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