Android research-Development of Android widget Basics

Reference address: http://mobile.51cto.com/widget-290079.htm

 

Ndroid widget DevelopmentCase implementation is the content to be introduced in this article, mainly to understand and learnAndroid widget DevelopmentApplication. Let's write about it today.Android widgetOfDevelopmentBecause it's time to wait early in the morning, I won't say it's too specific. Let's just imitate it, comrades! First, let's take a look:

 
The detailed steps of the demo are as follows:

1. Create an android project named widgetdemo.

2. Prepare materials. One is the widget icon and the other is the background of the widget. Storage directory:

3. Modify the string. xml file as follows:

2. <?XML Version="1.0" Encoding="UTF-8"?>
4. <Resources>
6. <String Name="Hello">Hello world, widetdemo!</String>
8. <String Name="App_name">Daystoworldcup</String>
10. </Resources>

Iv. EstablishmentWidgetContent Provider file. We create an XML folder under Res and create a new widget_provider.xmlCodeEntry:

2. <?XML Version="1.0" Encoding="UTF-8"?>
4. <Appwidget-provider Xmlns: Android=Http://schemas.android.com/apk/res/android"
6. Android: minwidth="50dip"
8. Android: minheight="50dip"
10. Android: updateperiodmillis="10000"
12. Android: initiallayout="@ Layout/main"
14. />

5. Modify the main. xml layout. The Code is as follows:

2. <?XML Version="1.0" Encoding="UTF-8"?>
4. <Linearlayout Xmlns: Android=Http://schemas.android.com/apk/res/android"
6. Android: Orientation="Vertical"
8. Android: layout_width="Fill_parent"
10. Android: layout_height="Fill_parent"
12. Android: Background="@ Drawable/wordcup"
14. >
16. <Textview
18. Android: ID="@ + ID/wordcup"
20. Android: layout_width="Fill_parent"
22. Android: layout_height="Wrap_content"
24. Android: Text="@ String/hello"
26. Android: textsize="12px"
28. Android: textcolor="# Ff0000"
30. />
32. </Linearlayout>

6. modify the code of widgetdemo. Java as follows:

2. Package com. Android. tutor;
4. Import java. util. calendar;
6. Import java. util. date;
8. Import java. util. gregoriancalendar;
10. Import java. util. timer;
12. Import java. util. timertask;
14. Import Android. appwidget. appwidgetmanager;
16. Import Android. appwidget. appwidgetprovider;
18. Import Android. content. componentname;
20. Import Android. content. context;
22. Import Android. widget. remoteviews;
24. Public class widetdemo extends appwidgetprovider {
26. /** Called when the activity is first created .*/
30. @ Override
32. Public void onupdate (context, appwidgetmanager,
34. Int [] appwidgetids ){
38. TimerTimer=NewTimer ();
40. Timer. scheduleatfixedrate (New mytime (context, appwidgetmanager), 1, 60000 );
42. Super. onupdate (context, appwidgetmanager, appwidgetids );
44. }
48. Private class mytime extends timertask {
50. Remoteviews;
52. Appwidgetmanager;
54. Componentname thiswidget;
58. Public mytime (context, appwidgetmanager ){
60. This. appwidgetmanager= Appwidgetmanager;
62. Remoteviews=NewRemoteviews (context. getpackagename (), R. layout. Main );
66. Thiswidget=NewComponentname (context, widetdemo. Class );
68. }
70. Public void run (){
74. DateDate=NewDate ();
76. CalendarCalendar=NewGregoriancalendar (2010,06, 11 );
78. LongDays= (Calendar. gettimeinmillis ()-date. gettime ()/1000)/86400;
80. Remoteviews. settextviewtext (R. Id. wordcup, "+ days +" days "from South Africa World Cup ");
82. Appwidgetmanager. updateappwidget (thiswidget, remoteviews );
86. }
88. }
90. }

7. modify the configuration file androidmanifest. xml. The Code is as follows:

2. <?XML Version="1.0" Encoding="UTF-8"?>
4. <Manifest Xmlns: Android=Http://schemas.android.com/apk/res/android"
6. Package="Com. Android. Tutor"
8. Android: versioncode="1"
10. Android: versionname="1.0">
12. <Application Android: icon="@ Drawable/icon" Android: Label="@ String/app_name">
14. <Cycler Android: Name=". Widetdemo"
16. Android: Label="@ String/app_name">
18. <Intent-Filter>
20. <Action Android: Name="Android. appwidget. Action. appwidget_update" />
22. </Intent-Filter>
24. <Meta-data Android: Name="Android. appwidget. provider"
26. Android: Resource="@ XML/widget_provider"
28. />
30. </Cycler>
32. </Application>
34. <Uses-SDK Android: minsdkversion="7" />
36. </Manifest>

8. Click "run" (CTRL + F11). After the operation is successful, we click "desktop" for a long time. The following two items are displayed. Click them one by one to see the top:

 

Summary: AnalysisAndroid widget DevelopmentThe implementation of the case is complete.Android widget DevelopmentContent learning is helpful to you!

 

This article is complete.