If you’re a Flutter developer, you may have written widget tests before. But have you unleashed their full power?
Judging by the Flutter developers I have worked with the last couple of years, I would venture it’s a “no”… Not because of lack of skills, I have worked with many excellent developers, but because best practices regarding testing take a little longer to establish when a framework is still “new”.
Continue reading “Unleash the full power of Flutter widget tests”
As software developers, we learn all the time. New frameworks, new programming languages, new dev ops, the list seems endless. So, we often plan to catch up with X and Y, through online courses, videos, blog posts, asking a colleague etc. Many mention it when giving career advice. And I have done so myself up until the end of 2019.
But it’s different now. I believe that the best you can do for your career as a software developer in 2020 is to focus on climate change*. Reduce your meat and dairy consumption**. Talk about climate change with your family, friends, colleagues. Contact your local politicians and ask that they bring in legislation that keeps fossil fuels in the ground. Contact any organisation you are a member or customer of, and ask them to divest from fossil fuels.
I know, I know, I’m mostly talking about communication skills. And, as software developers, we’re not always too comfortable with those. So it’s a big ask.
“I’m worried I will get behind if I don’t learn framework X and all the other developers do.”
Do you ever get distracted at work? Yes, me too…
We get distracted. By someone, a live issue, a meeting, a colleague asking a quick question, a broken build pipeline, and so on. Reasons are plenty.
We forget “where we were”.
Every workday, I write an ordered list of tasks I will do at the start of the next workday.
Just before logging off, I set aside 5 minutes.
This is useful to do this every workday. Don’t skip it. Particularly, don’t skip it on Friday at 5.30pm. I know you want to get out of the building, but stay 5 more minutes, you will thank yourself for it on Monday morning.
Continue reading “Software developers: the 5 minutes habit that will boost your workday”
When it comes to mobile apps, automated tests play a very important role in app maintenance. So, how do you write tests in Flutter?
As you would expect from a modern framework, Flutter offers both unit and integration tests. But it also offers something else: widget tests.
Widget tests are in between unit and integration. Like a unit test, they run on a simpler test environment (whereas integration tests run on an emulator or device). But they can actually test the UI. You can write a widget test that taps on a button.
With the Android SDK, I write UI tests with Espresso. It works well but the tests take a long time to run. It’s not a problem with CI, as we can use some good sharding libraries. But while I develop, I often run a subset on my local machine, to verify my work, and I get frustrated.
Therefore, I find the concept of widget tests very welcome. It will reduce the number of integration tests on a production app, moving some of them to widget tests.
In this code tutorial, we will create an app with a list page and a details page. On the details page, we can select/unselect an item. Its selected status is shown on the list page via a different background colour.
Then, we will write unit and widget tests to verify the behaviour of the app.
Continue reading “Flutter widget tests: a practical example”Flutter makes creating custom UI experiences easy. It really does. I mean it.
One example is complex gestures. How about starting a drag gesture to trigger something, and then moving the finger to control something else, and finally dropping it to confirm?
Continue reading “How to implement gestures across several widgets in Flutter”
A common pattern when showing a list on a website is allowing the users to filter it with a search term. So, how do you do this in AngularDart?
In this code tutorial, which uses AngularDart 5.0, we will create a simple web app with a list. Above the list, in a sibling component of the list, we will show an input field and a clear button. As the user types in the input, the list is filtered accordingly. If the user taps the clear button, all the items of the list are shown again and the input field is cleared.
The code is available on github.
A few weeks ago, I decided to publish my first Flutter app on the Apple app store. The app had been published on Android for almost a year, but I had actually never tested it on an iPhone. Did Flutter live up to its cross platform claims?
Here are a few things to consider & watch out for, especially if you come from an Android background.
It’s quite common for a native Android app to use productFlavors to set up several apps from the same source code. So, how easy is this to implement in Flutter?
In this code tutorial, we will set up a project with 2 app flavors. Each app will display the app name (specific per flavor), the current date (shared functionality, which includes a string), a short description (specific per flavor), and two images (one specific per flavor, one shared).
Continue reading “Creating flavors of a Flutter app (Flutter & Android setup)”
You may be an Android or Java developer, you’ve heard about Flutter, and are curious. So, is Dart easy to pick up as a Java developer?
The official website claims that Dart is “familiar to many existing developers”, and I generally agree with this statement. There is now a codelab Intro to Dart for Java developers: I do recommend you at least skim through it to get an overview.
In addition to the codelab, below is a list of concepts you will probably need to know fairly quickly.
setState … setState … setState … Once you code an app of medium complexity, it becomes very important to think about the performance impact of your Flutter widgets.
Thinking about app performance is about being a good app citizen. Not only the app will be smoother for the user, but also it will drain less battery. And we all know battery is still the single point of failure for smartphones!
The official Stateful Widget doc has some very helpful information on performance considerations. Here, I will focus on the first item: “Push the state to the leaves”.
In this code tutorial, we will set up a screen with a list of shopping items. Each item displays a title and a picture. Some items actually have several pictures available, so we will loop through them in the display, with the picture changing for that item every 2 seconds.
Continue reading “Improve your Flutter app performance: split your widgets”