Badge count is persisted after deleting an app and installing it again

Question

My application has a notification section in it, and the sum of the notifications are displayed in the form of Badge Count on the app icon. When the user accesses the notifi

Answer 1

Run freshInstallationCheck function in didFinishLaunchingWithOptions section.

    func freshInstallationCheck() {
        let defaults = UserDefaults.standard
        guard let currentAppVersion = Bundle.main.object(forInfoDictionaryKey: "CFBundleShortVersionString") as? String else { return }
        guard let previousVersion = defaults.string(forKey: "appVersion") else {
            // Key does not exist in UserDefaults, must be a fresh install
            print("fresh install")
            //  Writing version to UserDefaults for the first time
            defaults.set(currentAppVersion, forKey: "appVersion")
            // reinstall application, force to set icon to zero
            UIApplication.shared.applicationIconBadgeNumber = 0
            return
        }

        let comparisonResult = currentAppVersion.compare(previousVersion, options: .numeric, range: nil, locale: nil)
        switch comparisonResult {
        case .orderedSame:
            // nothing to do
            break
        case .orderedAscending, .orderedDescending:
            // new version update or downgrade

            break
        }

        // Updating new version to UserDefaults
        defaults.set(currentAppVersion, forKey: "appVersion")
    }