Issue with Application Packaging in Kotlin-CodePudding

I have an app I built, deployed and is being tested with Google Developer Tester Option. My app(s) i have been developing has a wierd issue I can not put my finger on.

The App is a simple Note Taking App. So there is not a lot of code. I done my main activity only has about 60 lines of code. Everything else is composed of classes.

When I test my app on my cellphone. There is a time delay of 5 seconds that a white screen shows while launching. Then it goes to the app.

I would usually put a splash screen. And its seamless in loading. Without the splash screen with normal code it shows the white screen for 5 seconds.

My question is, am I doing something or wrong or is this something with the transition of .apk to .aab when packaging?

I have read articles of people saying its a bug withing Android itself. I have no warnings or errors within the app.

This has me puzzled and any advice would be helpful.

Here is a screenshot of the start up process.

Then this happens for 5 seconds then the main app shows

Any help is appreciated.

CodePudding user response：

Your application can't launch instantly, the time it takes to launch an application depends on several hardware factors. So the launch time is different from one smartphone to another

https://developer.android.com/topic/performance/vitals/launch-time

CodePudding user response：

Ok after some test coding I finally solved the issue. To have the White Screen not appear you can create a splash screen or just a theme.

Theme should be set as follows

<style name="Theme.SplashScreen" parent="Theme.AppCompat.NoActionBar">
    <item name="android:windowDisablePreview">true</item>
</style>

Then in your SplashScreen.kt you can add the following

val handler = Handler(Looper.getMainLooper())
    handler.postDelayed({
        val intent = Intent(this, MainActivity::class.java)
        startActivity(intent)
        finish()
    }, 2000)

Then in your Manifest you need add the following:

<activity
        android:name=".SplashScreen"
        android:exported="true"
        android:theme="@style/Theme.SplashScreen">

        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity
        android:name=".MainActivity"
        android:exported="true">

    </activity>

This cuts the launch time with the Splash Screen to whatever your delay is set at.