Jan 22
Building a Flutter app? Avoid these common mistakes for a seamless experience.
Effortlessly build a Flutter app by avoiding these common mistakes. A smooth experience awaits.
Hello everyone, in this article we will cover common mistakes to avoid when developing a Flutter application. In order to avoid issues and bugs when developing a mobile app with Flutter, you need to avoid common mistakes.
It’s important we follow that, and I’m going to share my experience of what mistakes are made while developing apps and how I came up with better solutions. In my opinion, if you don’t make mistakes, you’re doing nothing. I’m a firm believer that making mistakes and learning from them is important, so mystic does not mean that we’ve made some mistakes so that we can give up, but we’re making some mistakes.
The purpose of all this is to make sure that we provide high quality code and a high performance application. So we can come up with a learning curve for ourselves and also create a best practice for others. We will see all those details, so you shouldn’t feel that you just stick to best practices and move. Share your mistakes and let us see how you overcame them.
Please let us know if you find any other major mistakes not covered here in the comment section. Firstly, let’s take a look at some common mistakes, let’s go over each one individually.
Testing is required for the application: The purpose of testing an application in Flutter is to ensure that the application functions as expected and works correctly. Testing includes unit testing, widget testing, and integration testing.
As an example of unit testing in Flutter, a specific function or method within a class might be tested to ensure it performs as intended. A unit test for a calculator application, for example, could confirm that when certain inputs are provided, the addition function returns the right result.
It is possible to test the visual appearance and behaviour of a button widget in Flutter. By pressing the button and tapping it, you can see if the colour changes.
Testing the interaction between different parts of the app is an example of integration testing in Flutter. Testing whether clicking a button triggers a specific action, such as opening a new screen or sending data.
In general, testing in Flutter ensures that the app behaves as expected and that any bugs or issues are caught and fixed before it is released.
It is important to handle errors properly: In order to build a reliable and stable app, you must handle errors carefully. Incorrect handling of errors can lead to crashes and unexpected behaviour in the app. Errors may cause the app to crash or malfunction if they are not handled properly.
Imagine you have a button in your Flutter app that sends a network request to a server. A server error, such as a 404 status code, may cause the app to crash if it is not handled properly by the app.
Instead of crashing the app, display a message to the user saying “Error: Could not connect to server”.
As well as catching errors, it is also important to validate user input and anticipate errors before they occur.
Future<void> _sendNetworkRequest() async {
try {
var response = await http.get('https://example.com/data');
if (response.statusCode != 200) {
throw Exception('Error: Could not connect to server');
}
// process response
} catch (e) {
print(e);
}
}In the above example, code inside the try block will execute the network request and check the status code. If the status code indicates an error, an exception is thrown and caught in the catch block. The error message can be printed to the console or displayed to the user.
It’s also good practice to use catchError and then functions to handle errors instead of using try-catch blocks.
Future<void> _sendNetworkRequest() async {
final response = await http.get('https://example.com/data')
.catchError((error) {
print(error);
return null;
})
.then((response) {
if (response.statusCode != 200) {
throw Exception('Error: Could not connect to server');
}
// process response
});
}This way, you can handle any error that occurs during the network request, such as network connectivity issues, in a more elegant way.
Orientation of devices should be properly handled: UI issues can arise when devices are not oriented properly.Providing a smooth user experience requires handling device orientations correctly. The app may not display correctly on different devices or when rotated when orientations are not handled properly.
Imagine a screen in your Flutter app that displays a grid of items. In portrait mode, the grid should have two columns, but in landscape mode, it should have three columns. The grid may not adjust correctly if the app does not handle the device orientation change correctly, and the items may be displayed incorrectly.
The OrientationBuilder widget can rebuild a part of the widget tree based on the orientation of the device.
OrientationBuilder(
builder: (BuildContext context, Orientation orientation) {
return GridView.count(
crossAxisCount: orientation == Orientation.portrait ? 2 : 3,
children: List.generate(100, (index) {
return Center(
child: Text(
'Item $index',
style: Theme.of(context).textTheme.headline,
),
);
}),
);
},
);As shown in the above example, the OrientationBuilder widget updates the number of columns in the grid based on the device’s orientation. When the device is rotated, the grid will automatically adjust to display the items correctly.
You can also use a package called flutter_screenutil which can handle the orientation, screen size, and scale factor of the device.
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
ScreenUtil.init(context, width: 1080, height: 1920, allowFontScaling: true);
return Scaffold(
body: Column(
children: <Widget>[
SizedBox(
height: ScreenUtil().setHeight(200),
width: ScreenUtil().setWidth(1080),
child: Image.asset('assets/images/bgImage.png'),
),
],
),
);
}
}In this way, you can handle the screen size and orientation change more effectively and easily.
It’s important to handle device orientations properly in order to provide a good user experience and to avoid any layout issues.
It is recommended to use named routes: By using named routes, you can navigate more easily through the app, and prevent errors due to incorrect navigation. Using named routes allows you to navigate between different screens and pages. Using them, you can give specific names to paths, making navigation easier and more organized.
For example, imagine you have a simple app with two screens: “Home” and “Settings”. Without using named routes, you might navigate to the “Settings” screen using the following code:
Navigator.push(
context,
MaterialPageRoute(builder: (context) => SettingsPage()),
);This code pushes a new screen onto the navigation stack and displays the “Settings” screen. However, without named routes, it can be difficult to know which route is being navigated to or to handle navigation in a more organized way.
A simple way to handle this is to use named routes. You can define the routes in the MaterialApp widget and give them specific names.
MaterialApp(
routes: {
'/': (context) => HomePage(),
'/settings': (context) => SettingsPage(),
},
);With named routes, you can navigate to the “Settings” screen using the following code:
Navigator.pushNamed(context, '/settings');This code pushes a new screen onto the navigation stack and displays the “Settings” screen, but now it’s clear which route is being navigated to.
You can also use Navigator.of(context).pushNamed('/settings'); to navigate to the named route '/settings'.
It’s also possible to pass parameters or arguments to a named route by using the pushNamed method's second argument.
Navigator.pushNamed(context, '/settings', arguments: 'data');This way you can use named routes to make navigation more organized, clear and easy to handle.
It’s always a good practice to use named routes in your flutter app, especially when you have multiple pages or screens in your app.
It is recommended to use dependency injection: the dependency injection pattern allows a class to receive the objects it needs instead of creating them itself. Flutter applications can benefit from dependency injection in terms of testability, maintainability, flexibility, and reusability.
Dependent injection is not built-in to Flutter, so developers must use third-party libraries or write their own.
As an example, let’s say you have a class called NetworkClient that makes network requests, and another class called HomePage that displays data from the network. In the absence of dependency injection, the HomePage class would create an instance of the NetworkClient class itself.
class HomePage extends StatelessWidget {
@override
Widget build(BuildContext context) {
NetworkClient client = NetworkClient();
//...
}
}In order to control the behavior of the HomePage class, you would have to mock the NetworkClient class. Due to this, it is also difficult to change the implementation of the NetworkClient class, because all of the classes that use it would also need to be updated.
By using dependency injection, the HomePage class would receive an instance of the NetworkClient class as a constructor parameter, as shown below:
class HomePage extends StatelessWidget {
final NetworkClient client;
HomePage({required this.client});
@override
Widget build(BuildContext context) {
//...
}
}Using a mocked NetworkClient class makes it easier to test the HomePage class. Additionally, only the classes that create the NetworkClient class would need to be updated, making it easier to change its implementation.
Using injectable or get_it for Dependency Injection in Flutter is easy.
Optimising app performance is necessary: A poorly optimized app can cause slow performance and poor user experience.
The goal of optimizing the performance of a Flutter app is to make sure the app runs smoothly and quickly, with no lags or delays. Apps can be made smaller and do less work by reducing the amount of work they do, using less memory and resources, and making use of fewer resources.
A simple example of optimizing the performance of a Flutter app is by using the Dart profiler. With this tool, developers can monitor their app’s performance in real-time and identify areas causing slowdowns or consuming too much resources. Developers can improve performance by modifying these areas of code.
By optimizing the performance of a Flutter app, we ensure that the app runs smoothly and efficiently, improving the user experience.
for more detail checkout here
Best practices for app architecture should be followed: Apps that do not follow best practices for app architecture can be difficult to maintain and scale.
failure to follow best practices in app architecture in Flutter can lead to a number of issues, such as a lack of organization, poor performance, and difficulty in maintaining and updating the app. One example of not following best practices is not separating the concerns of the different parts of the app.
For example, consider a simple weather app where all the data, business logic and UI are all in the same widget, this would make the code difficult to understand, hard to test and hard to update. If you want to add a feature, you will have to go through all the code to find the right place to add it, and if you want to fix a bug, it will be hard to find where the problem is.
By not separating the concerns, the app will become more complex and harder to understand, making it more difficult to update, test, and debug. This will ultimately lead to a poor user experience and a higher chance of bugs and crashes.
It is important to follow the best practices in app architecture in Flutter, such as using design patterns, separating concerns, and using state management tools, to create a well-organized, maintainable, and efficient app.
i know we have seen a lot of things not to avoid and what are the things we have to inculcate while we are developing flutter apps but how do we do it at a larger extent.
so i think we can solve this problem which i have followed and come up with some best practices or some of the mistakes that i have made and learnt is by talking to experts talking to developers expressing the concern that you have how you can solve them getting different views being a part of the community whether whether it is to share a knowledge or or find out what could be the alternative solution be a part of the community try to get it open.
so that you can get different views on your problems or solutions or a different perspective on what you’re building make mistakes unless you make mistake you will not know if this could be the next best practice so try to follow these approaches and you would be able to avoid those common mistakes and use the best practices to build a better app.
