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Dark theme

Dark theme is available in Android 10 (API level 29) and higher. It has many benefits:

  • Can reduce power usage by a significant amount (depending on the device’s screen technology).
  • Improves visibility for users with low vision and those who are sensitive to bright light.
  • Makes it easier for anyone to use a device in a low-light environment.

Dark theme applies to both the Android system UI and apps running on the device.

There are three ways to enable Dark theme in Android 10 (API level 29) and higher:

  • Use the system setting (Settings -> Display -> Theme) to enable Dark theme.
  • Use the Quick Settings tile to switch themes from the notification tray (once enabled).
  • On Pixel devices, selecting the Battery Saver mode enables Dark theme at the same time. Other OEMs may or may not support this behavior.

Supporting Dark theme in your app

In order to support Dark theme, you must set your app's theme (usually found in res/values/styles.xml) to inherit from a DayNight theme:

<style name="AppTheme" parent="Theme.AppCompat.DayNight">

You can also use MaterialComponents' dark theming:

<style name="AppTheme" parent="Theme.MaterialComponents.DayNight">

This ties the app's main theme to the system-controlled night mode flags and gives the app a default Dark theme (when it is enabled).

Themes and styles

Your themes and styles should avoid hard-coded colors or icons intended for use under a light theme. You should use theme attributes (preferred) or night-qualified resources instead.

Here are the two most important theme attributes to know about:

  • ?android:attr/textColorPrimary This is a general purpose text color. It is near-black in Light theme and near-white on Dark themes. It contains a disabled state.
  • ?attr/colorControlNormal A general-purpose icon color. It contains a disabled state.

We recommend using Material Design Components, since its color theming system (such as the theme attributes ?attr/colorSurface and ?attr/colorOnSurface) provides easy access to suitable colors. Of course, you can customize these attributes in your theme.

Changing themes in-app

You might want to allow users to change the app's theme while the app is running. Your app can let the user choose between themes.

When running on devices running Android 9 or earlier, the recommended theme options are:

  • Light
  • Dark
  • Set by Battery Saver (the recommended default option)

When running on Android 10 (API level 29) and higher, the recommended options are different, to allow the user to override the system default:

  • Light
  • Dark
  • System default (the recommended default option)

Note that if the user selects Light, then Battery Saver will not change that setting.

Each of the options map directly to one of the AppCompat.DayNight modes:

To switch the theme, call AppCompatDelegate.setDefaultNightMode().

Force Dark

Android 10 provides Force Dark, a feature for developers to quickly implement a Dark theme without explicitly setting a DayNight theme, as described above.

Force Dark analyzes each view of your light-themed app, and applies a dark theme automatically before it is drawn to the screen. Some developers use a mix of Force Dark and native implementation to cut down on the amount of time needed to implement Dark theme.

Apps must opt-in to Force Dark by setting android:forceDarkAllowed="true" in the activity's theme. This attribute is set on all of the system and AndroidX provided light themes, such as Theme.Material.Light. When you use Force Dark, you should make sure to test your app thoroughly and exclude views as needed.

If your app uses a dark theme (such as Theme.Material), Force Dark will not be applied. Similarly, if your app's theme inherits from a DayNight theme, Force Dark will not be applied, due to the automatic theme switching.

Disabling Force Dark on a view

Force Dark can be controlled on specific views with the android:forceDarkAllowed layout attribute or with setForceDarkAllowed().

Best Practices

Notifications and Widgets

For UI surfaces that you display on the device but do not directly control, it is important to make sure that any views you use reflect the host app’s theme. Two good examples are notifications and launcher widgets.

Notifications

Use the system-provided notification templates (such as MessagingStyle). This means that the system is responsible for ensuring the correct view styling is applied.

Widgets and custom notification views

For launcher widgets, or if your app uses custom notification content views, it is important to make sure you test the content on both the Light and Dark themes.

Common pitfalls to look out for:

  • Assuming that the background color is always light
  • Hardcoding text colors
  • Setting a hardcoded background color, while using the default text color
  • Using a drawable icon which is a static color

In all of these cases, use appropriate theme attributes instead of hardcoded colors.

Launch screens

If your app has a custom launch screen, it may need to be modified so that it reflects the selected theme.

Remove any hardcoded colors, for example any background colors pointing may be white. Use the ?android:attr/colorBackground theme attribute instead.

Note that dark-themed android:windowBackground drawables only work on Android Q.

Configuration changes

When the app’s theme changes (either through the system setting or AppCompat) it triggers a uiMode configuration change. This means that Activities will be automatically recreated.

In some cases you might want an app to handle the configuration change. For example, you might want to delay a configuration change because a video is playing.

An app can handle the implementation of Dark theme itself by declaring that each Activity can handle the uiMode configuration change:

<activity
    android:name=".MyActivity"
    android:configChanges="uiMode" />

When an Activity declares it handles configuration changes, its onConfigurationChanged() method will be called when there is a theme change.

To check what the current theme is, apps can run code like this:

Kotlin

val currentNightMode = configuration.uiMode and Configuration.UI_MODE_NIGHT_MASK
when (currentNightMode) {
    Configuration.UI_MODE_NIGHT_NO -> {} // Night mode is not active, we're using the light theme
    Configuration.UI_MODE_NIGHT_YES -> {} // Night mode is active, we're using dark theme
}

Java

int currentNightMode = configuration.uiMode & Configuration.UI_MODE_NIGHT_MASK;
switch (currentNightMode) {
    case Configuration.UI_MODE_NIGHT_NO:
        // Night mode is not active, we're using the light theme
        break;
    case Configuration.UI_MODE_NIGHT_YES:
        // Night mode is active, we're using dark theme
        break;
}