call other applications inside another android application

Have reached a block while programming on android.Is there any way to change the default desktop in the android emulator? The only thing i have achieved till now is uninstalling the system applications.I understand that only an application can have an icon...right? Is there any way that an application when launched displays a set of icons (which may or may not be separate applications)开发者_如何学编程? On clicking these icons either an application or an activity is launched....any help on this matter would be highly appreciated.

This answer gives more information.

The Home application in the Android open source project can only be built as part of a firmware image. It is not designed to be compiled just using the SDK. There is a sample Home application in your SDK, though, that builds with the SDK.

So, if your goal is to create a replacement home screen standalone app, use the Home app in your SDK as a starting point. If your goal is to create replacement firmware, download the entire firmware and build it that way.

Here is a link to the Home sample app.

there is an example in the samples included with the SDK, here is a little more info:

http://developer.android.com/resources/samples/Home/index.html

be sure to add these lines to your AndroidManifest.xml in the intent filters:

            <category android:name="android.intent.category.HOME"/>
            <category android:name="android.intent.category.DEFAULT" />

when you hit the "home" button you should have two options; the Android launcher, and the one you've programmed as a replacement. i believe there, you can choose the default. you can change the default by clearing the settings under settings/apps/manage apps/launcher/clear defaults.