private async Task <RouterState> GetRouterState(IObjectStateStore stateStore)
{
ObjectState existingState = null;
try
{
existingState = await stateStore.LoadStateAsync();
}
catch (Exception e)
{
this.Log().WarnException("Could not load state from state store.", e);
await InvalidateStateAsync(stateStore);
}
RouterState routerState = null;
try
{
routerState = (RouterState)existingState?.State;
}
catch (InvalidCastException e)
{
this.Log().WarnException($"Could not cast loaded state to {nameof(RouterState)}. Was a breaking change made to the app's stored data model?", e);
await InvalidateStateAsync(stateStore);
}
return(routerState);
}
public virtual async Task StartAsync()
{
RegisterDependencies();
StateStore = GetService <IObjectStateStore>();
var routerParams = GetService <RouterConfig>();
Router = GetService <IRouter>();
SetupSubscriptions(Router);
var routerState = await GetRouterState(StateStore);
await ResumeRouterAsync(Router, routerParams, routerState, StateStore);
await Router.ShowDefaultViewModelAsync();
started = true;
}
private static async Task SaveRouterStateAsync(IRouter router, IObjectStateStore stateStore)
{
var state = await ActivationHelpers.GetObjectStateAsync(router);
await stateStore.SaveStateAsync(state);
}
private static async Task InvalidateStateAsync(IObjectStateStore stateStore)
{
await stateStore.SaveStateAsync(null);
}
private async Task ResumeRouterAsync(IRouter router, RouterConfig routerConfig, RouterState routerState, IObjectStateStore stateStore)
{
await ActivationHelpers.InitObjectAsync(router, routerConfig);
try
{
if (routerState != null)
{
await ActivationHelpers.ResumeObjectStateAsync(router, routerState);
}
}
catch (Exception e)
{
this.Log().WarnException("Could not resume the router state.", e);
await InvalidateStateAsync(stateStore);
}
}