التنقل بين الشاشات وتمرير المعلمات

Every component registered as a screen in a React Navigation navigator automatically receives a navigation prop. This object provides methods to move between screens, go back, and manage the navigation stack. You can also access it in nested components using the useNavigation hook.

Call navigation.navigate('ScreenName') to move to another screen. If the screen is already in the stack and you navigate to it again, React Navigation will go to the existing instance rather than adding a duplicate. Use navigation.push('ScreenName') to always push a new instance.

Call navigation.goBack() to pop the current screen off the stack and return to the previous one. On iOS the swipe-back gesture is enabled by default. On Android, the hardware back button calls goBack automatically. Use navigation.popToTop() to jump all the way back to the first screen.

Pass a second argument to navigation.navigate to send parameters to the destination screen. The params object can contain any serializable data — IDs, strings, booleans. Avoid passing complex non-serializable objects like class instances or functions.

The destination screen receives a route prop alongside the navigation prop. Access the parameters you passed via route.params. Always provide defaults in case a screen is opened without params, for example when it is the initial screen.

Set initialParams on a Stack.Screen to provide default parameter values. These defaults merge with any params passed at runtime, so the screen always has a complete set of values to work with, even when opened as the initial route.

A screen can update its own params using navigation.setParams. This is useful when an action on the current screen (like editing a form field) should be reflected in the navigation header title. The params update triggers a re-render of the screen.

Deep child components that are not registered screens do not receive the navigation prop automatically. Use the useNavigation() hook from React Navigation to access the navigation object anywhere inside the navigator tree without prop drilling.

Similarly, use the useRoute() hook to access route.params in a non-screen component. This is useful when you have a deeply nested component that needs to read the current screen's parameters without threading the route prop through every level.

You can dynamically set the navigation header title based on route params by passing a function to the options prop. The function receives the route object, allowing you to use param values as the screen title without extra state.

To send data from a child screen back to its parent, use navigation.navigate with the parent screen's name and include the return data as params. The parent screen will receive the updated params. Alternatively, pass a callback function as a param to the child screen and call it before going back.

In this lesson you learned: use navigation.navigate to move to another screen, pass params as the second argument to navigate, and read params with route.params in the destination screen. Next up we explore the Bottom Tab Navigator.