Android Program Development: (2) use intent-2.4 use intent to transmit data

In addition to the ability to return data results from an activity, it is also very common to transmit data to an activity.

1. Create a new project, passdata.

2. Code in Main. xml.

[Java]View plaincopy

1. <? XML version = "1.0" encoding = "UTF-8"?>
2. <Linearlayout xmlns: Android = "http://schemas.android.com/apk/res/android"
3. Android: layout_width = "fill_parent"
4. Android: layout_height = "fill_parent"
5. Android: Orientation = "vertical">
7. <Button
8. Android: Id = "@ + ID/btn_secondactivity"
9. Android: layout_width = "fill_parent"
10. Android: layout_height = "wrap_content"
11. Android: onclick = "onclick"
12. Android: text = "click to go to second activity"/>
14. </Linearlayout>

3. In the Res/layout folder, create the secondactivity. xml file.[Java]View plaincopy

1. <? XML version = "1.0" encoding = "UTF-8"?>
2. <Linearlayout xmlns: Android = "http://schemas.android.com/apk/res/android"
3. Android: layout_width = "fill_parent"
4. Android: layout_height = "fill_parent"
5. Android: Orientation = "vertical">
7. <Textview
8. Android: layout_width = "fill_parent"
9. Android: layout_height = "wrap_content"
10. Android: text = "Welcome to second activity"/>
12. <Button
13. Android: Id = "@ + ID/btn_mainactivity"
14. Android: layout_width = "fill_parent"
15. Android: layout_height = "wrap_content"
16. Android: onclick = "onclick"
17. Android: text = "click to return to main activity"/>
19. </Linearlayout>

4. Create an activity subclass: secondactivity. java.[Java]View plaincopy

1. Public class secondactivity extends activity {
2. @ Override
3. Public void oncreate (bundle savedinstancestate ){
4. Super. oncreate (savedinstancestate );
5. Setcontentview (R. layout. secondactivity );
7. // --- Get the data passed in using getstringextra ()---
8. Toast. maketext (this, getintent (). getstringextra ("str1 "),
9. Toast. length_short). Show ();
11. // --- Get the data passed in using getintextra ()---
12. Toast. maketext (this,
13. Integer. tostring (getintent (). getintextra ("age1", 0 )),
14. Toast. length_short). Show ();
16. // --- Get the bundle object passed in ---
17. Bundle bundle = getintent (). getextras ();
19. // --- Get the data using the getstring ()---
20. Toast. maketext (this, bundle. getstring ("str2"), Toast. length_short)
21. . Show ();
23. // --- Get the data using the getint () method ---
24. Toast. maketext (this, integer. tostring (bundle. getint ("age2 ")),
25. Toast. length_short). Show ();
26. }
28. Public void onclick (view ){
29. // --- Use an intent object to return data ---
30. Intent I = new intent ();
32. // --- Use the putextra () method to return some
33. // Value ---
34. I. putextra ("age3", 45 );
36. // --- Use the setdata () method to return some value ---
37. I. setdata (URI. parse ("something passed back to main activity "));
39. // --- Set the result with OK and the intent object ---
40. Setresult (result_ OK, I );
42. // --- Destroy the current activity ---
43. Finish ();
44. }
45. }

5. The code in androidmanifest. xml.[Java]View plaincopy

1. <? XML version = "1.0" encoding = "UTF-8"?>
2. <Manifest xmlns: Android = "http://schemas.android.com/apk/res/android"
3. Package = "net. horsttnann. passingdata"
4. Android: versioncode = "1"
5. Android: versionname = "1.0" type = "codeph" text = "/codeph">
7. <Uses-SDK Android: minsdkversion = "10"/>
9. <Application
10. Android: icon = "@ drawable/ic_launcher"
11. Android: Label = "@ string/app_name">
12. <Activity
13. Android: Name = ". passingdataactivity"
14. Android: Label = "@ string/app_name">
15. <Intent-filter>
16. <Action Android: Name = "android. Intent. Action. Main"/>
18. <Category Android: Name = "android. Intent. Category. launcher"/>
19. </Intent-filter>
20. </Activity>
21. <Activity
22. Android: Name = "net. Manoel. passingdata. secondactivity"
23. Android: Label = "second activity">
24. <Intent-filter>
25. <Action Android: Name = "net. horsttnann. passingdatasecondactivity"/>
27. <Category Android: Name = "android. Intent. Category. Default"/>
28. </Intent-filter>
29. </Activity>
30. </Application>
32. </Manifest>

6. The code in passdataactivity.

public class PassingDataActivity extends Activity {    /** Called when the activity is first created. */    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);    }        public void onClick(View view) {    Intent i = new     Intent("net.manoel.PassingDataSecondActivity");    //---use putExtra() to add new key/value pairs---                i.putExtra("str1", "This is a string");    i.putExtra("age1", 25);    //---use a Bundle object to add new key/values     // pairs---      Bundle extras = new Bundle();    extras.putString("str2", "This is another string");    extras.putInt("age2", 35);                    //---attach the Bundle object to the Intent object---    i.putExtras(extras);                    //---start the activity to get a result back---    startActivityForResult(i, 1);    }        public void onActivityResult(int requestCode,     int resultCode, Intent data)    {        //---check if the request code is 1---        if (requestCode == 1) {            //---if the result is OK---             if (resultCode == RESULT_OK) {                //---get the result using getIntExtra()---                Toast.makeText(this, Integer.toString(                    data.getIntExtra("age3", 0)),                     Toast.LENGTH_SHORT).show();                      //---get the result using getData()---                Toast.makeText(this, data.getData().toString(),                     Toast.LENGTH_SHORT).show();            }                    }    }}

7. debug by F11.

The program is started for the first time:

Jump to secondactivity:

Return passdataactivity: