Implementing Persistent Storage for Application State

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Context

The application was unable to retain certain runtime data after being fully closed. Each time the app relaunched, all in-memory values were reset, causing user-specific information or app state to be lost. This negatively affected user experience and continuity across sessions.

Description

The root cause was that important app data was stored only in memory and never written to persistent storage. When the app process was terminated, all temporary values were cleared.

To ensure a stable and seamless user experience, essential app state must be saved to persistent storage and restored during initialization.

Solution/Approach

• During app startup, previously saved values are retrieved and applied.
• Whenever relevant data changes, updated values are written to persistent storage.
• All read/write operations are asynchronous to prevent blocking the main thread.
• The mechanism is designed to support any type of application state (e.g., progress, settings, preferences, achievements).

Implementation Step

• Initialize persistent storage during the app startup (setContext method).
• Read the previously saved xxx value.
• Ensure that all storage operations are handled asynchronously to avoid blocking the main thread.

Sample Code

async setContext(context: common.Context) {
  await storage.init(context)
  this.xxx= await storage.get('xxx') || 0
}

async saveProgress(level: number) {
  await storage.set('currentLevel', level)
}

Key Takeaways

• App data progress now persists across app restarts.
• Persistent storage ensures a consistent and reliable user experience.
• Initialization logic is simplified and aligned with the app lifecycle.
• The solution is lightweight, scalable, and easily extendable to support other game data (e.g., achievements, settings).

Written by Aycanur Ucar