Android launcher Research (4) ---- development of desktop application shortcuts!

Hello everyone, today I want to share with you the development of the launcher desktop shortcut icon. We all know that the shortcut icon consists of two parts: the application icon and the Application name. In fact, the shortcut icon in launcher only inherits the textview control and re-draws it to make the background light gray (I don't know what the color is) the elliptical background, the displayed text color is white. Textview has the Android: drawabletop; drawablebottom (not all of them are written here) attribute to display the application icon.

I don't need to talk much about it. Let's just look at the example. Let's just tap into the code and grow faster.

Step 1: Create an android project named applicationdemo. For example:

Step 2: Create a colors. xml file in the values directory and define the colors to use. The Code is as follows:

<? XML version = "1.0" encoding = "UTF-8"?> <Br/> <resources> <br/> <color name = "white"> # ffffff </color> <br/> <color name = "black" >#000000 </color> <br/> <color name = "bubble_dark_background"> # b2191919 </color> <br/> </resources> <br/>

Step 3: Create a bubbletextview class that inherits textview. The Code is as follows:

Package COM. tutor. application; <br/> Import android. content. context; <br/> Import android. graphics. canvas; <br/> Import android. graphics. paint; <br/> Import android. graphics. rectf; <br/> Import android. text. layout; <br/> Import android. util. attributeset; <br/> Import android. widget. textview; <br/> public class bubbletextview extends textview {<br/> Private Static final int corner_radius = 8; <br/> Private Static final int padding_h = 5; <br/> Private Static final int padding_v = 1; <br/> private final rectf mrect = new rectf (); <br/> private paint mpaint; <br/> Public bubbletextview (context) {<br/> super (context); <br/> Init (); <br/>}< br/> Public bubbletextview (context, attributeset attrs) {<br/> super (context, attrs); <br/> Init (); <br/>}< br/> Public bubbletextview (context, attributeset attrs, int defstyle) {<br/> super (context, attrs, defstyle ); <br/> Init (); <br/>}< br/> private void Init () {<br/> setfocusable (true ); <br/> // we need extra padding below to prevent the bubble being cut. <br/> setpadding (padding_h, 0, padding_h, padding_v); <br/> mpaint = new paint (paint. anti_alias_flag); <br/> mpaint. setcolor (getcontext (). getresources () <br/>. getcolor (R. color. bubble_dark_background); <br/>}< br/> @ override <br/> protected void drawablestatechanged () {<br/> invalidate (); <br/> super. drawablestatechanged (); <br/>}< br/> @ override <br/> Public void draw (canvas) {<br/> final layout = getlayout (); <br/> final rectf rect = mrect; <br/> final int left = getcompoundpaddingleft (); <br/> final int Top = getextendedpaddingtop (); <br/> rect. set (left + layout. getlineleft (0)-padding_h, <br/> top + layout. getlinetop (0)-padding_v, <br/> math. min (left + layout. getlineright (0) + padding_h, <br/> getscrollx () + getright ()-getleft (), <br/> top + layout. getlinebottom (0) + padding_v); <br/> canvas. drawroundrect (rect, corner_radius, corner_radius, mpaint); <br/> super. draw (canvas); <br/>}< br/>

Step 4: Modify the main. xml layout file. The Code is as follows:

<? XML version = "1.0" encoding = "UTF-8"?> <Br/> <linearlayout xmlns: Android = "http://schemas.android.com/apk/res/android" <br/> Android: Orientation = "vertical" <br/> Android: layout_width = "fill_parent" <br/> Android: layout_height = "fill_parent" <br/> <textview <br/> Android: layout_width = "wrap_content" <br/> Android: layout_height = "wrap_content" <br/> Android: drawabletop = "@ drawable/icon" <br/> Android: TEXT = "applicationdemo" <br/> Android: textcolor = "@ color/Black" <br/> <COM. tutor. application. bubbletextview <br/> Android: layout_width = "wrap_content" <br/> Android: layout_height = "wrap_content" <br/> Android: drawabletop = "@ drawable/icon" <br/> Android: textcolor = "@ color/White" <br/> Android: TEXT = "applicationdemo" <br/> </linearlayout> <br/>

Step 5: Modify the androidmanifest. xml file. Note that we have added a transparent style to the activity. launcher is actually a transparent activity.

The Code is as follows (8th lines of code ):

<? XML version = "1.0" encoding = "UTF-8"?> <Br/> <manifest xmlns: Android = "http://schemas.android.com/apk/res/android" <br/> package = "com. tutor. application "<br/> Android: versioncode =" 1 "<br/> Android: versionname =" 1.0 "> <br/> <application Android: icon = "@ drawable/icon" Android: Label = "@ string/app_name"> <br/> <activity Android: Name = ". applicationdemo "<br/> Android: theme =" @ Android: style/theme. wallpaper. notitlebar "<br/> Android: Label =" @ string/app_name "> <br/> <intent-filter> <br/> <action Android: Name =" android. intent. action. main "/> <br/> <category Android: Name =" android. intent. category. launcher "/> <br/> </intent-filter> <br/> </activity> <br/> </Application> <br/> <uses-SDK Android: minsdkversion = "7"/> <br/> </manifest>

Step 6: run the above project and check the effect as follows:

Change Android: drawableleft to Android: drawabletop. The effect is as follows:

OK ~ You're done. Stop and go to bed !!!