In MainActivity, I call SincActivity. This screen has a "start" button, a TextView and a ProgressBar to show the status.
The button start an AsyncTask. This AsyncTask updates the components on the screen, and also in the notification area.
The notification area can be clicked. I passed into their creation which Activity it should open. I have spent SincActivity.
When the user is on the screen SincActivity and click the button, all components are updated as expected.
When I click on the notification area, android opens a new screen SincActivity, with initial values.
It's as if somewhere, android execute: "new SincActivity"; What I need is to be shown always the same screen.. the same instance. Almost like a singleton.
Is this possible?
UPDATE
AndroidManifest.xml
<uses-sdk
   android:minSdkVersion="11"
   android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<application
   android:allowBackup="true"
   android:icon="@drawable/ic_launcher"
   android:label="@string/app_name"
   android:theme="@style/AppTheme" >
    <activity
       android:name="br.com.rokko.gabinetemobile.MainActivity"
       android:label="@string/app_name"
       android:configChanges="orientation|keyboardHidden|screenSize"
       android:theme="@style/FullscreenTheme" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity
       android:name="br.com.rokko.gabinetemobile.ModeloActivity"
       android:configChanges="orientation|keyboardHidden|screenSize"
       android:label="@string/title_activity_modelo"
       android:theme="@style/FullscreenTheme" >
    </activity>
    <activity
       android:name="br.com.rokko.gabinetemobile.SincActivity"
       android:label="@string/sincronizacao" ><!-- android:launchMode="singleInstance" don't work -->
    </activity>
</application>