Dart and Flutter Flutter How to write unit test for thrown exception
I didn't know how to write unit test for a function that throws an exception. Therefore. I looked into the solution and ...
Dart and Flutter 
Dart and Flutter Dart Compare two objects – how to deep equal
This article explains how to compare two objects in Dart. How can we implement if we want to do deep equal? What is the good way to override hashCode and == operator?
Dart and Flutter Flutter Provider example ChangeNotifierProvider and Consumer
I have used only setState in order to update the view but I faced a problem while I developed my own package grouped exp...
Dart and Flutter Flutter Draggable Expansion Tile
When we want to make a widget draggable, Draggable class is useful and easy to to use. An Expansion Tile has children. H...
Dart and Flutter Flutter Dynamic expansion tile for group data
I needed a expansion tile for grouping data. I wanted to show item list like a folder structure on VS Code. Top parents ...
Dart and Flutter Build error after upgrading Flutter
When I upgraded Flutter from 2.2.3 to 2.5.0 debug console showed a lot of build errors. I didn't understand what caused ...
JavaScript/TypeScript Node-RED flow test is slow if flow is big
I have tried several times to reduce test time of Node-RED flow test and failed. For the flow test, I use node-red-node-...
Dart and Flutter Flutter Add TextField widget dynamically
TextField requires TextEditingController that must be disposed. If we want to add TextField dynamically we also need to ...
Dart and Flutter Flutter move screen up on the keyboard
Scaffold widget has persistentFooterButton property. When we assign widgets there they are hidden under the keyboard. re...
JavaScript/TypeScript TypeScript – Using never type in switch case
TypeScript offers never data type for values that never occur. I've never seen it in my work but I found it useful for s...