关于Android12以上的闪屏兼容

Custom Splash Screen on Android - Why You’re Doing It Wrong - pl-coding.com

对应的视频

https://www.youtube.com/watch?v=eFZmMSm1G1c

国内大部分应用都有闪屏，如果到12上没有处理的话，会出现两个闪屏的结果

因为12默认会有一个闪屏

官方给出了迁移建议

https://developer.android.com/develop/ui/views/launch/splash-screen/migrate?hl=zh-cn

郭林的这篇文章也写的非常详细

Android 12 SplashScreen API快速入门

添加依赖

使用官方的库可以兼容之前的设备，开屏有一样的表现

implementation("androidx.core:core-splashscreen:1.0.1")

定义主题

theme.xml

   <style name="Theme.App.Starting" parent="Theme.SplashScreen">
        <item name="windowSplashScreenBackground">@color/black</item>
        <item name="postSplashScreenTheme">@style/Theme.AnimatedSplashScreen</item>
    </style>

theme.xml 31

 <style name="Theme.App.Starting" parent="Theme.SplashScreen">
        <item name="windowSplashScreenBackground">@color/black</item>
        <item name="postSplashScreenTheme">@style/Theme.AnimatedSplashScreen</item>
        <item name="android:windowSplashScreenAnimatedIcon">@drawable/animated_logo</item>
    </style>

31多了动画定义

animated_logo.xml

<?xml version="1.0" encoding="utf-8"?>
<animated-vector xmlns:android="http://schemas.android.com/apk/res/android"
    android:drawable="@drawable/logo">

    <target
        android:animation="@animator/logo_animator"
        android:name="animationGroup" />

</animated-vector>

其中 logo 定义图标，logo_animator定义动画了对logo中 animationgroup进行一些动画操作

logo.xml

<vector android:height="50dp" android:viewportHeight="3500"
    android:viewportWidth="3500" android:width="50dp" xmlns:android="http://schemas.android.com/apk/res/android">
    <group
        android:name="animationGroup"
        android:pivotX="1750"
        android:pivotY="1750">
        <path android:fillColor="#00f15e"
            android:pathData="m1843.9,1192.1l-274.6,444.5c-5.2,8.5 -14.5,13.6 -24.5,13.6h-721.7c-6.3,0 -12.4,-2.1 -17.4,-5.9l-249,-189.3c-3.5,-2.7 -6.3,-6.1 -8.3,-10L3,354.4c-7.1,-14.2 -1.4,-31.5 12.9,-38.6 4,-2 8.4,-3 12.9,-3h1372.9c10.9,0 20.8,6.2 25.7,15.9l417.8,835.5c4.5,8.9 4,19.5 -1.3,28Z" android:strokeWidth="0"/>
        <path android:fillColor="#00f15e"
            android:pathData="m2056.1,1913.7l-628.7,1257.4c-4.9,9.7 -14.8,15.9 -25.7,15.9H28.8c-15.9,0 -28.7,-12.9 -28.7,-28.7 0,-4.5 1,-8.9 3,-12.9l534.2,-1068.1c2,-3.9 4.8,-7.3 8.3,-10l249,-189.3c5,-3.8 11.1,-5.9 17.4,-5.9h1218.4c15.9,0 28.7,12.9 28.7,28.8 0,4.4 -1,8.8 -3,12.8Z" android:strokeWidth="0"/>
        <path android:fillColor="#00f15e"
            android:pathData="m3485.2,1190l-602.1,454.5c-5,3.8 -11.1,5.8 -17.3,5.8h-511.3c-10.9,0 -20.8,-6.2 -25.7,-15.9L1688.8,354.3c-7.1,-14.2 -1.3,-31.5 12.9,-38.6 4,-2 8.4,-3 12.8,-3h1020.8c5.2,0 10.3,1.4 14.8,4.1l616,368.3c6.5,3.9 11.2,10.2 13.1,17.6l116.6,457.3c2.9,11.2 -1.3,23.1 -10.6,30Z" android:strokeWidth="0"/>
        <path android:fillColor="#00f15e"
            android:pathData="m3471.1,3187.2c16.1,0 29.4,-13.3 28.9,-29.4 -15.5,-444.4 -380.7,-800 -828.9,-800s-813.4,355.5 -828.8,800c-0.6,16.1 12.8,29.4 28.9,29.4l1599.9,-0.1Z" android:strokeWidth="0"/>
    </group>
</vector>

<?xml version="1.0" encoding="utf-8"?>
<objectAnimator xmlns:android="http://schemas.android.com/apk/res/android"
    android:duration="1000"
    android:interpolator="@anim/overshoot_interpolator">

    <propertyValuesHolder
        android:propertyName="rotation"
        android:valueType="floatType"
        android:valueFrom="0.0"
        android:valueTo="360.0" />

    <propertyValuesHolder
        android:propertyName="scaleX"
        android:valueType="floatType"
        android:valueFrom="0.0"
        android:valueTo="0.4" />

    <propertyValuesHolder
        android:propertyName="scaleY"
        android:valueType="floatType"
        android:valueFrom="0.0"
        android:valueTo="0.4" />

</objectAnimator>

应用主题

        android:theme="@style/Theme.App.Starting"
        

这样当应用启动后，不需要添加额外的界面，就可以有一个logo的动画闪屏

但是动画结束，如果我们想延长呢可以加setKeepOnScreenCondition

class MainActivity : ComponentActivity() {

    private val viewModel by viewModels<MainViewModel>()

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        installSplashScreen().apply {
            setKeepOnScreenCondition {
                !viewModel.isReady.value
            }
            setOnExitAnimationListener { screen ->
                val zoomX = ObjectAnimator.ofFloat(
                    screen.iconView,
                    View.SCALE_X,
                    0.4f,
                    0.0f
                )
                zoomX.interpolator = OvershootInterpolator()
                zoomX.duration = 500L
                zoomX.doOnEnd { screen.remove() }

                val zoomY = ObjectAnimator.ofFloat(
                    screen.iconView,
                    View.SCALE_Y,
                    0.4f,
                    0.0f
                )
                zoomY.interpolator = OvershootInterpolator()
                zoomY.duration = 500L
                zoomY.doOnEnd { screen.remove() }

                zoomX.start()
                zoomY.start()
            }
        }

        setContent {
            AnimatedSplashScreenTheme {
                // A surface container using the 'background' color from the theme
                Surface(
                    modifier = Modifier.fillMaxSize(),
                    color = MaterialTheme.colorScheme.background
                ) {
                    Greeting("Android")
                }
            }
        }
    }
}

但是基本上。。老板不会满意这么简单的动画

以前做的比较多的是，使用Lottie的库，可以有一些非常流畅绚丽的动画效果。

那如果自己做闪屏的话，就需要再12上除去默认的闪屏

很不幸，在Android 12设备上，您不能通过他们提供的API直接禁用默认的启动画面。如果您的应用程序具有自定义启动画面，并且您不想迁移到这种新方法，则可以尝试以下黑客技巧。基本上，您需要在res\values-v31\themes.xml中覆盖您的启动屏幕主题并设置一个透明的图标。

<!-- My custom theme for splash screen activity -->
<style name="Theme.Splash" parent="Theme.Main">
    <item name="android:windowBackground">@color/background</item>
    <!-- Set a transparent .png as your icon -->
    <item name="android:windowSplashScreenAnimatedIcon">@drawable/transparent_image</item>
</style>

这将帮助你消除app在启动时闪屏期间出现的默认应用程序图标。

that's it