Can I launch different Activities on startup depending on user preferences?

Question

I have a ListActivity and a MapActivity. I would like to launch either one of these activities on application startup that has been chosen by the user in a preferences window.

So far the only way I see to launch an activity on application startup is to specify it in the application manifest file using...

  <activity android:name=".MyActiivty"
        android:label="@string/app_name">
     <intent-filter>
        <action android:name="android.intent.action.MAIN" />
        <category android:name="android.intent.category.LAUNCHER" />
     </intent-filter>
  </activity>

I am thinking I might have to start an activity that does nothing but looks at the user preferences and then launches either the ListActivity or MapActivity. Seems like a waste to have an activity do nothing but launch another activity. In my research I have not found any solution to this problem. Any suggestions would be greatly appreciated.

Thanks & Regards, Dave

Answer 1

First, don't create some third activity. Just have the LAUNCHER Activity be either the list or the map, and have it call startActivity() on the other one (plus finish() ) in onCreate() before calling setContentView() when needed. That way, ~50% of the time, you're launching the right activity.

In principle, you could have both activities have a LAUNCHER <intent-filter> , only enabling one. However, that will not work with desktop shortcuts, which will route to a specific activity (whichever one happened to be configured when they made the shortcut). If this does not concern you, you might go this route. However, try to test it with a few devices and custom home screens -- I'm not sure if everyone will pick up on your change immediately.

Answer 2

I just added the following code to the onCreate() method an it worked like a charm.

    Intent intent;

    intent = new Intent(this, MyMap.class);
    startActivity( intent );
    finish();

Answer 3

for new folks (me), following is dave's answer, plus changes i needed to make to AndroidManifest.xml.

Main activity:

 Intent intent;

 intent = new Intent(this, DisplayMessageActivity.class);
 startActivity( intent );

changes to xml file, from -> http://developer.android.com/training/basics/firstapp/starting-activity.html

AndroidManifest.xml:

<activity
        android:name="com.mycompany.myfirstapp.DisplayMessageActivity"
        android:label="@string/title_activity_display_message"
        android:parentActivityName="com.mycompany.myfirstapp.MyActivity" >
        <meta-data
            android:name="android.support.PARENT_ACTIVITY"
            android:value="com.mycompany.myfirstapp.MyActivity" />
    </activity>