Single Instance of Activity

Question

My application has three activities say A -> B-> C.

Activity A is called from another activity through startActivityForResult(). Acti

Answer 1

You may be able to use a static variable to determine other data. I am not sure how much or what type of data you are looking to access from the other Activities, though.

Also writing to persistent storage may work, but again - the vagueness of what data you are storing and how makes it difficult to answer. Just write/read the persistent storage in the onResume and onSuspend methdod of each Activity (or create super Activity class and extend it for A, B and C.

Answer 2

Using android:launchMode="singleTask" is probably the best approach, since it won't recreate the activity if it's already running. Just add it to the activity in your AndroidManifest.xml, and you should be all set.

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

Here's another question that might be useful: Android singleTask or singleInstance launch mode?