Develop Reference

How to make app as a default system launcher?

I have developed the launcher application, for the first time when I installed it on device android system pop up chooser dialogue with two options i.e. Always & Just once. I selected "Always" now my app becomes default launcher but issue is when I update the app, the system pop up the same chooser dialogue again, I don't want to show that pop up. How to make the app as a default system launcher? To achieve this, Do I need to create system level app?
I have used following permission to make the app a launcher
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.HOME" />
<category android:name="android.intent.category.DEFAULT" />
<category android:name="android.intent.category.MONKEY" />
</intent-filter>

It is not possible to change the user preferences. Google does not allow developer to change user preferences.
A workaround may be useful, you can check for if your application is default launcher through a service and then prompt user to choose your application as default.
You can find how to check if your application is the default launcher from here (tried this one, it works for me) or here
Then you can prompt the user to select your application if it is not the default launcher. A workaround to do so is given here.

Android how to start activity on Boot-up

Let me describe you what I want: I want to build a "master app" and set it so that when the phone is powered up, it immediately goes into the master app. The user can never exit this app (this will be used for something like parental control), and he can only launch other apps from within it.
Basically it will be like a "custom desktop".
I must stress out, it is important that this app never exits. As long as the phone is started, this is the only environment that the user has access to.
Now after I explained what I need, I will need your help to tell me what am I looking for. Is this some kind of "default launcher" that I keep hearing about? Or how is this called?
How can I do it?
Thanks

Add this into Manifest.
<receiver
android:name=".Bootupclass"
android:enabled="true"
android:permission="android.permission.RECEIVE_BOOT_COMPLETED" >
</receiver>
Bootupclass
public class Bootupclass extends BroadcastReceiver{
#Override
public void onReceive(Context context, Intent intent) {
//write intent here
}
}

I need someone to give me the exact code needed to make the app:
Here Goes,
If you make an app as a launcher app, and if it is the ONLY launcher app within your system, it will of course be started when you switch on your device. And also when you click on the home button, since your app is the only launcher app within the system, the same would be started.
so ,
1) start on bootup 2) be the default action when pressing the home button (the "desktop")
could both be merged into 1.
You mentioned that your phone is rooted, So easiest way to achieve what you require would be to
1.Install your app with just these lines within the manifest. i.e within your first activity. Nothing else is required. (this would make your app as a launcher app)
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.HOME"/>
<category android:name="android.intent.category.DEFAULT" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
2.Un-install the default launcher application within your device.

What is being asked in the question body is different from the question title.
Listening to BOOT_COMPLETED will do literally what is requested by title - give control to the application once when device is powered on or restarted.
It is not enough to achieve the real goal - to prevent user from exiting the application and reaching "normal" home screen - once user presses "exit" or "home", he will essentially leave your app. While you can intercept "Exit" button and prevent it from quitting your app, "home" button is not possible to block programmatically.
In order to make and app like parental control and prevent user from reaching unwanted apps you need to implement "custom home screen" or "custom launcher" (which is the same thing).
It is rather large topic, but this seems to be a good starting point: Android - creating custom launcher.
And because author insists on "exact code", to make your app to start instead of a home screen (after boot or pressing "home" button), you need the following in the manifest:
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.HOME"/>
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
After install, press "home" button - you will be given a choice of standard launcher or your app. Check "use as default" and select your app - from now on it will start instead of the normal home screen.
Beware, though, that there are few known issues with custom launchers. One is - you have to block access to settings, otherwise user can switch back to default launcher. Also, after your app is updated (i.e. you post new version) user will be asked what home screen to use and can choose default launcher.

I must stress out, it is important that this app never exits This I believe is not possible.
From your requirement it seems that you require a MDM solution. Upwards of Android 2.2 device administration APIs have been available. Check out http://developer.android.com/guide/topics/admin/device-admin.html
The user will have to install your app and allow it to be a Device Administrator. (You can see currently available administrators from Setting -> Location and Security -> Device Administrator). Now as an administrator you can control features on device eg. disallow apps to be uninstalled, prevent installation of specific apps, disallow launch of specific apps. wipe device if security is breached etc. You can also prevent your app from being uninstalled.
There are apps available with such features. I can name Maas360 off the top of my head.
Disclaimer: I haven't tried the device administration apis myself.

Air app on Android to launch another application

I have an Android AIR application (developed with Flex SDK 4.5.1) for which I need to block the Home Button, as the app is used by patients in a hospital without supervision, i.e. it is crucial that they cannot leave the app.
It seems that the only way to hijack the Home Button is to be registered as the default launcher, so that your own app gets the focus when home is pressed. This is easily achieved in the manifest, such as:
<activity android:excludeFromRecents="false">
<intent-filter>
<category android:name="android.intent.category.DEFAULT"/>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
<category android:name="android.intent.category.HOME"/>
</intent-filter>
</activity>
Now the problem is: If I do quit the application, the original launcher should be made available to the user and I think the solution would be to just start the original launcher, but how should I do that? The original Android-way of "intents" is not available in AIR and the navigatetoURL() function seems to work only for special URIs, e.g. "market://.." launches the default market app, however, I need to execute an arbitrary application...
Edit: I am referring to a mobile Android App running in this case on an Archos tablet, but it could run on any Android device with AIR installed, such as a typical mobile phone like the HTC desire. With "home button" I am referring to the respective hardware button that allows the user to switch applications (or, to be more exact, to switch to a launcher app that typically shows all the apps as icons to tap on). This "home button" functionality I need to block, as the user should not be able to easily switch to another application.

This is probably a less useful answer but disabling device buttons sounds like something that should be handled at the OS layer and not at the Application layer. Might want to have a custom build of Android for this purpose.

Android: don't boot Launcher - run my application instead on startup

I've built Android from source and would like to launch directly into my application and NOT launch Launcher at all. Does anyone know what to change to launch an applicable .apk instead of Launcher on boot?
Running launcher causes a host of problems with my masking the fact Android is running.
- The unlock screen
- The status bar
- The menu & home icons
It would be best simply not to launch Launcher and go directly into the application from the Android boot logo.
Thanks,
Kevin

There is much easier solution that allows you not to rebuild Android. Just fill the main Activity of your application (in AndroidManifest.xml) with:
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.HOME" />
<category android:name="android.intent.category.DEFAULT" />
And after first start, reboot your device and than make your application's main Activity the default Home Screen (check the CheckBox at the bottom of choose dialog).

How to change default Android's Desktop application?

I hear that the Android's desktop is an application that I can change.
I'm searching for some information about how to do that.

I guess you mean when you press the home button you want to have your app there instead of the default home screen? And do you mean on a non-rooted phone?
I use an intent filter for that, i.e. I want my activity to start on phone boot-up and be the default home screen.
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
<category android:name="android.intent.category.HOME"/>
<category android:name="android.intent.category.DEFAULT"/>
</intent-filter>
On a regular phone, the user will get an option to choose between your app and the default home screen though at first, although he can mark a checkbox then to always choose this app as the default screen then - but your app cannot force the user to do that.

In the market you can search for Home Replacements. Once you install one and press the home button you will get a Choose Dialog, that let's you pick from the default Home and the newly installed one.
The current Home Screen that I use is Launcher Pro.