Summary of intent usage in Android

Android does not need to parse explicit intent because the target component is clear. Android needs to parse implicit intent, map intent to the activity, intentreceiver, or service that can process the intent.
The intent parsing mechanism mainly finds the matching intent by finding all intentfilters registered in androidmanifest. XML and the intent defined in them. In this parsing process, Android uses the intent action, type, and category attributes to determine the attributes. The judgment method is as follows:
* If the intent specifies an action, the action must be included in the intentfilter action list of the target component; otherwise, the action cannot be matched;
* If the intent does not provide a type, the system will obtain the data type from the data. Like action, the Data Type list of the target component must contain the intent data type. Otherwise, the data type does not match.
* If the data in the intent is not a content: Type Uri and the intent does not explicitly specify its type, it will match according to the scheme (such as http: or mailto :) of the data in the intent. Similarly, the scheme of intent must appear in the scheme list of the target component.
* If intent specifies one or more category categories, these categories must all appear in the Set category list. For example, intent contains two categories: launcher_category and alternative_category. The parsed target component must contain at least these two categories.
Intent-filter Definition
Examples of setting attributes:
<Action Android: Name = "com. example. Project. show_current"/>
<Category Android: Name = "android. Intent. Category. Default"/>
<Data Android: mimetype = "Video/MPEG" Android: Scheme = "HTTP".../>
<Data Android: mimetype = "image/*"/>
<Data Android: Scheme = "HTTP" Android: TYPE = "Video/*"/>
Complete instance
<Activity Android: Name = "noteslist" Android: Label = "@ string/title_notes_list">
<Intent-filter>
<Action Android: Name = "android. Intent. Action. Main"/>
<Category Android: Name = "android. Intent. Category. launcher"/>
</Intent-filter>
<Intent-filter>
<Action Android: Name = "android. Intent. Action. View"/>
<Action Android: Name = "android. Intent. Action. Edit"/>
<Action Android: Name = "android. Intent. Action. Pick"/>
<Category Android: Name = "android. Intent. Category. Default"/>
<Data Android: mimetype = "Vnd. Android. cursor. DIR/vnd. Google. Note"/>
</Intent-filter>
<Intent-filter>
<Action Android: Name = "android. Intent. Action. get_content"/>
<Category Android: Name = "android. Intent. Category. Default"/>
<Data Android: mimetype = "Vnd. Android. cursor. Item/vnd. Google. Note"/>
</Intent-filter>
</Activity>
Intent usage instance
1. No parameter for activity jump
Intent it = new intent (activity. Main. This, activity2.class );
Startactivity (it );
2. pass data to the next activity (use bundle and intent. putextras)
Intent it = new intent (activity. Main. This, activity2.class );
Bundle bundle = new bundle ();
Bundle. putstring ("name", "this is from mainactivity! ");
It. putextras (bundle); // it. putextra ("test", "shuju ");
Startactivity (it); // startactivityforresult (it, request_code );
You can use the following methods to obtain data:
Bundle bundle = getintent (). getextras ();
String name = bundle. getstring ("name ");

3. Return the result to the previous activity (use setresult to start the activity for startactivityforresult (it, request_code)
Intent intent = getintent ();
Bundle bundle2 = new bundle ();
Bundle2.putstring ("name", "this is from showmsg! ");
Intent. putextras (bundle2 );
Setresult (result_ OK, intent );
4. Call back the result processing function (onactivityresult) of the previous activity)
@ Override
Protected void onactivityresult (INT requestcode, int resultcode, intent data ){
// Todo auto-generated method stub
Super. onactivityresult (requestcode, resultcode, data );
If (requestcode = request_code ){
If (resultcode = result_canceled)
Settitle ("cancle ");
Else if (resultcode = result_ OK ){
String temp = NULL;
Bundle bundle = data. getextras ();
If (bundle! = NULL) temp = bundle. getstring ("name ");
Settitle (temp );
}
}
}
The following are some other intent usage examples (from javaeye)
Display webpage
1. Uri uri = URI. parse ("http://google.com ");
2. Intent it = new intent (intent. action_view, Uri );
3. startactivity (it );
Show Map
1. Uri uri = URI. parse ("Geo: 38.899533,-77.036476 ");
2. Intent it = new intent (intent. action_view, Uri );
3. startactivity (it );
4. // other geo uri examples
5. // GEO: latitude, longpolling
6. // GEO: latitude, longpolling? Z = zoom
7. // GEO: 0, 0? Q = My + street + address
8. // GEO: 0, 0? Q = business + near + city
9. // Google. Streetview: cbll = Lat, LNG & white = 1, yaw, pitch, zoom & MZ = mapzoom
Route Planning
1. Uri uri = URI. parse ("http://maps.google.com/maps? F = D & saddr = startlat % 20 startlng & daddr = endlat % 20 endlng & 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
Call
1. // call the dialing program
2. Uri uri = URI. parse ("Tel: 0800000123 ");
3. Intent it = new intent (intent. action_dial, Uri );
4. startactivity (it );
1. // directly call
2. Uri uri = URI. parse ("Tel: 0800000123 ");
3. Intent it = new intent (intent. action_call, Uri );
4. startactivity (it );
5. // use this file, which must be added to androidmanifest. xml.
6. // <uses-Permission id = "android. Permission. call_phone"/>

Send SMS/MMS
1. // call the SMS Program
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. // send messages
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. // send 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 );
Send 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. // transfer the attachment
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 "));
Play multimedia
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 Problems
1. // search for an application
2. Uri uri = URI. parse ("Market: // search? Q = pname: pkg_name ");
3. Intent it = new intent (intent. action_view, Uri );
4. startactivity (it );

// Display information about an application
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 Application
1. Uri uri = URI. fromparts ("package", strpackagename, null );
2. Intent it = new intent (intent. action_delete, Uri );
3. startactivity (it );