I have added badges in react native stack navigator for cart and wish-list count. These counts must be fetched from API on every screen change or back event. I also want to update these count on add to cart and add to wish-list event from Product screen
Can anyone suggests me how to do this ?
Any reference code or article will be very helpful.
Thanks in Advance.
If there is a need to update the UI globally from any screen of the app then we can implement global state management.
There are two simple ways to implement the global state which updates UI when changes made to it.
React Redux
React Context API
Use one of there and Make changes in the global state and assign the value to the UI Component the need for UI change is.
You can simply call an API and update the global state to update the badge count.
check out the official docs to implement the global state:
For React Redux: https://react-redux.js.org/
For Context API: https://reactjs.org/docs/context.html
Related
I have this react-native application using AppNavigator handling navigation between screens. I have trouble updating the paused (AppNavigator calls these screens "Blurred") screens.
I would like to be able to update the inactive screens from an active one.
I tried to add a listener on app notifications or subscribing to specific changes in a mobx store that should update the component, however the screen component won't react when not active/focused.
How can I make sure the screens updates when not active? I am unsure if I am tackling this fundamentally wrong.
In previous versions of react-navigation there was a way to disable lazy loading but that has been taken out in the newer versions.
What you are asking for will hinder you in the long term. It will basically keep all the screens loaded in the memory. You shouldn't need that just to update them. Instead you can update the MobX store and when the screen becomes active again look for the changes and update accordingly.
Use NavigationEvents to listen to when the screen becomes active.
So in my app I have a main component which have switch navigator and then inside switch navigator I have a tab navigator which renders different screens. I have registered notification handler in top component.
Now the problem is that when notification is received, I want to make some changes on screens inside tab navigator.
I have read about redux which will provide common store so state could be updated but I dont want to use that.
I have also read about lifting state up but in my case i have more nested components so I dont want to do that as well.
So suggest me some way to do it?
I have solved the problem by using react context api. It is simple wrap your top level component with provider and define some veriable and access that variable in any component.
as written in the react-navigation page:
Warning: in the next major version of React Navigation, to be released in Fall 2018, we will no longer provide any information about how to integrate with Redux and it may cease to work.
In the next version of react-navigation it could be hard to use redux with react-navigation.
My question is: what can I do to use states (and passing states between screens) in a react-navigation app without using redux?
For children of navigator
react-navigation gives you an withNavigation HOC, so you can easily wrap the component inside it to access the navigation state and navigate.
Why you integrate react navigation with redux?
For me, I want to be able to perform navigation actions from outside of my components(screens). Eg: Redux-saga. If we don't integrate, we can't navigate via redux-saga.
For a task like that we don't need to integrate react-navigation and redux. We just need to use NavigationService.
I am new to React Native and am working on a simple app, the app loads data structured like file folder hierarchy, so at top level, when a item is clicked, I want to switch to next level and Etc. every level has the same data, I guess I need to use the same component, I want to use react navigation to switch between levels, but I cannot do this because the same component is used.
Of course you can say just change the components' state with different data, but I need the navigation animation effect and navigating to upper level when click the back navigation component at the top.
Please help, thanks]1
Since I am using StackNavigation, using "push" is the answer,
this.props.navigation.push('ScreenName');
see this link: https://reactnavigation.org/docs/en/navigating.html
I have developed a application using react native map. I would like to know does the onRegionChange() method is called by default whenever the onUserLocationChange() is trigger?
After deeper search in the code source, the response is NO.
onRegionChange function called continuously when the region changes, such as when a user is dragging the map.