Navigation and routing are crucial aspects of app development in Flutter. Flutter, being an open source mobile app framework, provides a variety of options for app navigation and routing. In this article, we will discuss in detail about navigation and routing in Flutter, from the basics to the advanced ones.
To begin with, navigation is the process of transitioning between different pages (also known as routes) within an application. Routing, on the other hand, is a mechanism that allows developers to define the structure and flow of the application. In other words, navigation is about "how" to move between pages, while routing is about "what" exactly those pages are.
1. Basic navigation in Flutter
In Flutter, the Navigator class is used to navigate between routes. The Navigator works like a stack, where routes are stacked on top of each other. When a new path is browsed, it is pushed onto the browser stack. And when the user goes back, the current route is popped from the stack.
To navigate to a new route, you can use the Navigator.push method, passing in the current context and the route you want to navigate to. To go back to the previous route, you can use the Navigator.pop method.
2. Named Routing in Flutter
In larger applications, it can be difficult to manage multiple routes and navigation between them. This is where named routing can come in handy. With named routing, you can define all your routes in one place and refer to them by name.
To use named routing, you need to define a String Map and WidgetBuilder in the MaterialApp or CupertinoApp. Each Map key is the name of the route and the corresponding value is the function that will build that route.
3. Routing generated in Flutter
Generated routing is a more advanced routing technique in Flutter. It allows you to define routes dynamically based on some logic or condition. For example, you might want to show an error page when an unknown route is navigated.
To use generated routing, you need to provide a function for the onGenerateRoute parameter of the MaterialApp or CupertinoApp. This function will be called whenever the Navigator is asked to navigate to a route with the pushNamed method.
4. Passing Arguments Between Routes
Occasionally, you may want to pass some data from one route to another. This can easily be done in Flutter. When navigating to a new route, you can pass any object to the push method arguments argument.
5. Routing Custom Transitions
Finally, Flutter also allows you to customize routing transitions. By default, Flutter uses a slide transition for iOS and a fade transition for Android. However, you can override this by providing your own transition function for the transitionsBuilder parameter of the MaterialPageRoute or CupertinoPageRoute.
In summary, navigation and routing are fundamental aspects of application development in Flutter. They allow you to define the structure and flow of your application and provide a great user experience. Therefore, it is important to understand and master these concepts to become an effective Flutter developer.