Package com.mixpanel.android.mpmetrics

Interface MixpanelAPI.Flags

Enclosing class:
MixpanelAPI
public static interface MixpanelAPI.Flags
Core interface for using Mixpanel Feature Flags. You can get an instance by calling MixpanelAPI.getFlags() (assuming such a method exists).

The Flags interface allows you to manage and retrieve feature flags defined in your Mixpanel project. Feature flags can be used to remotely configure your application's behavior, roll out new features gradually, or run A/B tests.

It's recommended to load flags early in your application's lifecycle, for example, in your main Application class or main Activity's onCreate method.

A typical use case for the Flags interface might look like this: 

 

 public class MainActivity extends Activity {
 MixpanelAPI mMixpanel;
 Flags mFlags;

 public void onCreate(Bundle saved) {
 super.onCreate(saved);
 MixanelOptions mpOptions = new MixpanelOptions.Builder().featureFlagsEnabled(true).build();
 mMixpanel = MixpanelAPI.getInstance(this, "YOUR MIXPANEL TOKEN", true, mpOptions);
 mFlags = mMixpanel.getFlags();

 // Asynchronously load flags
 mFlags.loadFlags();

 // Example of checking a flag asynchronously
 mFlags.isFlagEnabled("new-checkout-flow", false, isEnabled -> {
 if (isEnabled) {
 // Show new checkout flow
 } else {
 // Show old checkout flow
 }
 });

 // Example of getting a flag value synchronously after ensuring flags are ready
 if (mFlags.areFlagsReady()) {
 String buttonLabel = (String) mFlags.getVariantValueSync("home-button-label", "Default Label");
 // Use buttonLabel
 }
 }
 }
See Also:

  • Method Details

    • loadFlags

      void loadFlags()
      Asynchronously loads flags from the Mixpanel server if they haven't been loaded yet or if the cached flags have expired. This method will initiate a network request if necessary. Subsequent calls to get flag values (especially asynchronous ones) may trigger this load if flags are not yet available.

    • areFlagsReady

      boolean areFlagsReady()
      Returns true if flags have been successfully loaded from the server and are currently available for synchronous access. This is useful to check before calling synchronous flag retrieval methods like getVariantSync(String, MixpanelFlagVariant) to avoid them returning the fallback value immediately.
      Returns:
      true if flags are loaded and ready, false otherwise.

    • getVariantSync

      @NonNull MixpanelFlagVariant getVariantSync(@NonNull String featureName, @NonNull MixpanelFlagVariant fallback)
      Gets the complete feature flag data (key and value) synchronously.

      IMPORTANT: This method can block the calling thread if it needs to wait for flags to be loaded (though the provided implementation detail suggests it returns fallback immediately if not ready). It is strongly recommended NOT to call this from the main UI thread if areFlagsReady() is false, as it could lead to ANR (Application Not Responding) issues if blocking were to occur.

      If flags are not ready (i.e., areFlagsReady() returns false), this method will return the provided fallback value immediately without attempting to fetch flags or block.

      Parameters:
      featureName - The unique name (key) of the feature flag to retrieve.
      fallback - The MixpanelFlagVariant instance to return if the specified flag is not found in the loaded set, or if flags are not ready. This must not be null.
      Returns:
      The MixpanelFlagVariant for the found feature flag, or the fallback if the flag is not found or flags are not ready.

    • getVariantValueSync

      @Nullable Object getVariantValueSync(@NonNull String featureName, @Nullable Object fallbackValue)
      Gets the value of a specific feature flag synchronously.

      IMPORTANT: Similar to getVariantSync(String, MixpanelFlagVariant), this method may involve blocking behavior if flags are being loaded. It's advised to check areFlagsReady() first and avoid calling this on the main UI thread if flags might not be ready.

      If flags are not ready, or if the specified featureName is not found, this method returns the fallbackValue immediately.

      Parameters:
      featureName - The unique name (key) of the feature flag.
      fallbackValue - The default value to return if the flag is not found, its value is null, or if flags are not ready. Can be null.
      Returns:
      The value of the feature flag (which could be a String, Boolean, Number, etc.), or the fallbackValue.

    • isEnabledSync

      boolean isEnabledSync(@NonNull String featureName, boolean fallbackValue)
      Checks if a specific feature flag is enabled synchronously. A flag is considered enabled if its value evaluates to true.
      • If the flag's value is a Boolean, it's returned directly.
      • If the flag's value is a String, it's considered true if it equals (case-insensitive) "true" or "1".
      • If the flag's value is a Number, it's considered true if it's non-zero.
      • For other types, or if the flag is not found, it relies on the fallbackValue.

      IMPORTANT: See warnings on getVariantSync(String, MixpanelFlagVariant) regarding potential blocking and the recommendation to check areFlagsReady() first, especially when calling from the main UI thread.

      Returns fallbackValue immediately if flags are not ready or the flag is not found.

      Parameters:
      featureName - The unique name (key) of the feature flag.
      fallbackValue - The default boolean value to return if the flag is not found, cannot be evaluated as a boolean, or if flags are not ready.
      Returns:
      true if the flag is present and evaluates to true, otherwise false (or the fallbackValue).

    • getVariant

      void getVariant(@NonNull String featureName, @NonNull MixpanelFlagVariant fallback, @NonNull FlagCompletionCallback<MixpanelFlagVariant> completion)
      Asynchronously gets the complete feature flag data (key and value).

      If flags are not currently loaded, this method will trigger a fetch from the Mixpanel server. The provided completion callback will be invoked on the main UI thread once the operation is complete.

      If the fetch fails or the specific flag is not found after a successful fetch, the fallback data will be provided to the completion callback.

      Parameters:
      featureName - The unique name (key) of the feature flag to retrieve.
      fallback - The MixpanelFlagVariant instance to return via the callback if the flag is not found or if the fetch operation fails. This must not be null.
      completion - The FlagCompletionCallback that will be invoked on the main thread with the result (either the found MixpanelFlagVariant or the fallback). This must not be null.

    • getVariantValue

      void getVariantValue(@NonNull String featureName, @Nullable Object fallbackValue, @NonNull FlagCompletionCallback<Object> completion)
      Asynchronously gets the value of a specific feature flag.

      If flags are not currently loaded, this method will trigger a fetch. The completion callback is invoked on the main UI thread with the flag's value or the fallbackValue.

      Parameters:
      featureName - The unique name (key) of the feature flag.
      fallbackValue - The default value to return via the callback if the flag is not found, its value is null, or if the fetch operation fails. Can be null.
      completion - The FlagCompletionCallback that will be invoked on the main thread with the result (the flag's value or the fallbackValue). This must not be null.

    • isEnabled

      void isEnabled(@NonNull String featureName, boolean fallbackValue, @NonNull FlagCompletionCallback<Boolean> completion)
      Asynchronously checks if a specific feature flag is enabled. The evaluation of "enabled" follows the same rules as isEnabledSync(String, boolean).

      If flags are not currently loaded, this method will trigger a fetch. The completion callback is invoked on the main UI thread with the boolean result.

      Parameters:
      featureName - The unique name (key) of the feature flag.
      fallbackValue - The default boolean value to return via the callback if the flag is not found, cannot be evaluated as a boolean, or if the fetch operation fails.
      completion - The FlagCompletionCallback that will be invoked on the main thread with the boolean result. This must not be null.