Adding a splash screen to Flutter apps

Question

How would you approach adding a splash screen to Flutter apps? It should load and display before any other content. Currently, there is a brief flash of color before the Scaffold(home:X) widget loads.

Answer 1

I want to bring some more light on the actual way of doing a Splash screen in Flutter.

I followed a little bit the trace here and I saw that things aren't looking so bad about the Splash Screen in Flutter.

Maybe most of the devs (like me) are thinking that there isn't a Splash screen by default in Flutter and they need to do something about that. There is a Splash screen, but it's with white background and nobody can understand that there is already a splash screen for iOS and Android by default.

The only thing that the developer needs to do is to put the Branding image in the right place and the splash screen will start working just like that.

Here is how you can do it step by step:

First on Android (because is my favorite Platform :) )

1. Find the "android" folder in your Flutter project.

2. Browse to the app -> src -> main -> res folder and place all of the variants of your branding image in the corresponding folders. For example:

• the image with density 1 needs to be placed in mipmap-mdpi,
• the image with density 1.5 needs to be placed in mipmap-hdpi,
• the image with density 2 needs to be placed in mipmap-xdpi,
• the image with density 3 needs to be placed in mipmap-xxdpi,
• the image with density 4 needs to be placed in mipmap-xxxdpi,

By default in the android folder there isn't drawable-mdpi, drawable-hdpi, etc., but we can create them if we want. Because of that fact the images need to be placed in the mipmap folders. Also the default XML code about the Splash screen (in Android) is going to use @mipmap, instead of @drawable resource (you can change it if you want).

3. The last step on Android is to uncomment some of the XML code in drawable/launch_background.xml file. Browse to app -> src -> main -> res-> drawable and open launch_background.xml. Inside this file, you shall see why the Slash screen background is white. To apply the branding image which we placed in step 2, we have to uncomment some of the XML code in your launch_background.xml file. After the change, the code should look like:

    <!--<item android:drawable="@android:color/white" />-->
   
    <item>
   
        <bitmap
            android:gravity="center"
            android:src="@mipmap/your_image_name" />
   
    </item>
   

Please pay attention that we comment the XML code for the white background and uncomment the code about the mipmap image. If somebody is interested the file launch_background.xml is used in styles.xml file.

Second on iOS:

1. Find the "ios" folder in your Flutter project.

2. Browse to Runner -> Assets.xcassets -> LaunchImage.imageset. There should be LaunchImage.png, [email protected], etc. Now you have to replace these images with your branding image variants. For example:

• the image with density 1 needs to override LaunchImage.png,
• the image with density 2 needs to override [email protected],
• the image with density 3 needs to override [email protected],
• the image with density 4 needs to override [email protected],

If I am not wrong [email protected] doesn't exist by default, but you can easily create one. If [email protected] doesn't exist, you have to declare it in the Contents.json file as well, which is in the same directory as the images. After the change my Contents.json file looks like this :

{
  "images" : [
    {
      "idiom" : "universal",
      "filename" : "LaunchImage.png",
      "scale" : "1x"
    },
    {
      "idiom" : "universal",
      "filename" : "[email protected]",
      "scale" : "2x"
    },
    {
      "idiom" : "universal",
      "filename" : "[email protected]",
      "scale" : "3x"
    },
    {
      "idiom" : "universal",
      "filename" : "[email protected]",
      "scale" : "4x"
    }
  ],
  "info" : {
    "version" : 1,
    "author" : "xcode"
  }
}

That should be all you need, next time when you run your app, on Android or iOS you should have the right Splash Screen with the branding image which you added.

Thanks