将FCM通知中的Android应用的前一个实例置于前台

Question

On my app I have a Splash Screen set with intent:

<activity
        android:name=".Splash"
        android:label="@string/app_name"
        android:screenOrientation="portrait"
        android:theme="@style/AppTheme.NoActionBar">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>

My app then opens a ".MainActivity", which is where all the action happens. Although when I get a push FCM notification and tap it, the app restarts and I get a new instance of everything. How do I keep the same instance of the app but just bring it to the foreground, basically like iOS does.

Answer 1

intent.setFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP);

If FLAG_ACTIVITY_SINGLE_TOP is set, the activity will not be launched if it is already running at the top of the history stack.

Referenced from: How to use Flags in android ?