What's the difference between errors and exceptions in Flutter?
→ Errors are programmer mistakes. They are fatal and we should not try to recover from them → Exceptions are failure conditions that are our of our control. We should handle them and recover gracefully
Thread 🧵
Errors are fatal and when they happen the program cannot recover normally.
→ we want to discover (and fix) them as early as possible in the development process → we should track them in production using a crash reporting solution, so that we can measure impact and severity
The most common errors we may encounter are:
AssertionErrorTypeErrorArgumentErrorRangeErrorUnimplementedErrorStateError
and many others.
They all extend the base Error class, and the full list of errors can be found here:
Exceptions are not fatal and we should always handle them gracefully.
We can choose to map them to our own exception type inside a try/catch block.
Or we can let them propagate on the call stack (until something else catches them).
How to recover when an exception happens?
Eventually, we want to catch them somewhere and show a user-friendly error message.
One common way to do this is to emit an error state that the widget can listen to.
I've covered this before:
Some common exceptions you may encounter are:
FormatExceptionIOExceptionPlatformExceptionTimeoutException
They all implement the base Exception class (you may create your own if you want), and the full list can be found here:
That's it for now. I'll be covering error & exception handling more in detail in upcoming tweets/threads.
Want more tips like this?
Follow me: @biz84.
And if you want to go more in depth, my Flutter course covers the most important topics. 👇
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