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A Collection of Flutter and Dart Tips and Tricks

A Collection of Flutter and Dart Tips and Tricks
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Category: Flutter / UI Helpers
Watchers: 5
Star: 33
Fork: 3
Last update: Apr 6, 2021
Resource links
https://github.com/vandadnp/flutter-tips-and-tricks

Table of Contents

Dart List Enumeration with Index

Applying Mixins to Other Mixins in Dart

Parameter Types in Dart

Custom Exceptions in Dart

rethrowing Exceptions in Dart

mixins and JSON Parsing in Dart

mixins vs abstract classes in Dart

Drawing Shapes in Flutter with LayoutBuilder, CustomPaint and CustomPainter

Generic Type Aliases in Dart

Callable Classes in Dart

Synchronous Generators in Dart

Implicit Interfaces in Dart

Did you know that in #Dart, every #class implicitly exports an #interface that can be #implemented (as opposed to #extended) by other classes? This is called "implicit interface".

Do you know how "const" constructors work in #Dart?

Did you know that in #Dart, it is actually preferred to use #async and #await over using raw #Futures?

In #Dart, you can use a combination of #Initializer #List plus default values for your class #member #fields to create elegant and handy convenience initializers

Did you know that in #Dart, you can extract elements of a certain type from your Lists using the #whereType #generic #function instead of calculating the #equality yourselves?

Do you know about #Type #Promotion in Dart?

"address" is an optional field of the "Person" class. If you look at the "doThis()" function you see that I'm saving the value of address in a local variable and then comparing it with null and then returning if it's null. The Dart compiler is intelligent enough to understand that after the if-statement, "address" is NOT null anymore since you've already compared it with null and returned from the function.

If you look at the "insteadOfThis" function, the first one, the Dart compiler cannot make the same assumption if you don't first store the value of address in a local variable. In that first function the Dart compiler, even after the if-statement, needs you to refer to address as an optional, using "address?" syntax.

The mechanism the Dart compiler uses in the "doThis()" function is called Type Promotion.

4 lines of #Dart code that include the #spread operator, #cascade #operator, #generics, #extensions, #private prefix and #getters

Functions as First Class Citizens in Dart

0 Open More issues
Closed

Merge pull request #1 from vandadnp/main

New updates

opened Dec 12, 2021 by OmarBakry-eg 5
Closed

Cool but, My browser is not able to load this repo

Great tips thanks, the only problem is I can't load this page entirely. I think it's too heavy to load on a single page causes browser to stuck.

In Progress 
opened Mar 21, 2022 by aisivan36 4
Closed

Reduce image size(without reduce qualify) that makes images load faster

Reduce image size(without reduce qualify) that makes images load faster

opened Jan 15, 2022 by SajadRahimi1 4
Closed

Add the update to the release description

Hey! Thanks for a very cool repo ✌️

Would be nice if the release message contained the tip itself or at least a link to the new section. So if I see the release in the feed, I could just read it by entering the release page.

opened Aug 28, 2022 by nivisi 3
Closed

Built-in way to get sum and average of list items in dart

You use the reduce method to get the sum of list items in dart. Calculating the Sum of List Items in Dart

Actually there is a built-in way for doing that:

import 'package:collection/collection.dart';

void main() {
  final list = [1, 2, 3, 4];
  final sum = list.sum;
  print(sum); // prints 10
  final average = list.average; 
  print(average); // prints 2.5
}
opened Oct 25, 2021 by tmaihoff 3
Closed

very good, have you considered a Chinese version

null

opened Jan 4, 2022 by songxing10000 2
Open

Typo in "365 - Recoveringg Stream Errors in Flutter"

Typo in "365 - Recoveringg Stream Errors in Flutter"

Likely you planned saying "Recovering" (single G)?

opened Nov 13, 2022 by gaddlord 0
Open

Factory Constructors in Dart

In "Factory Constructors in Dart" there is no definition for "Rect".

opened Sep 15, 2022 by AtomSeven 1
Open

"Enum associated values" tip is useless

This tip is overly complicated, you can just do enumValue.index : https://github.com/vandadnp/flutter-tips-and-tricks/blob/main/tipsandtricks/enum-associated-values-in-dart/enum-associated-values-in-dart.md

opened Aug 26, 2022 by orevial 0
Open

"Classes as enums" tip is obsolete

Using classes as enum has become obsolete since Dart 2.17, this tip could be removed !

https://github.com/vandadnp/flutter-tips-and-tricks/blob/main/tipsandtricks/classes-as-enums-in-dart/classes-as-enums-in-dart.md

opened Aug 26, 2022 by orevial 1
Open

"Convert Enums to Strings in Dart" tip is out of date

This tip : https://github.com/vandadnp/flutter-tips-and-tricks/blob/main/tipsandtricks/convert-enums-to-strings-in-dart/convert-enums-to-strings-in-dart.md

is out of date because we now have enumValue.name since Dart 2.15 so I think this tip can be removed 😉

opened Aug 26, 2022 by orevial 0
Open

Null-Aware Infix Operators in Dart - likely unneeded code on line "return shadow + (other ?? 0) as T"

RE: https://github.com/vandadnp/flutter-tips-and-tricks/blob/main/tipsandtricks/null-aware-infix-operators-in-dart/null-aware-infix-operators-in-dart.md

Having:

T? operator +(final T? other) {
  final shadow = this;
  if (shadow != null) {
    return shadow + (other ?? 0) as T;
  } else {
    return null;
  }
}

and the test:

test('Test null + operator', () {
    int? var1;
    var1++;
    var1 += 1;
    var1 = var1 + 1;
    var1 = 2;
    var1++;
    var1 += 1;
    var1 = var1 + 1;
    expect(var1, 5);
}

The test runs successfully but with code coverage we can see that the line

return shadow + (other ?? 0) as T;

never gets called which leads me to the speculation that shadow always equals to NULL when the extension is called and the extension is not "attached" if T is not null.

opened Aug 20, 2022 by gaddlord 1

375(Dec 30, 2022)

Canonicalized maps in Dart are maps where for each key, you can calculate a unique value and should two keys get the same unique value, the last one always wins. Here is an example of how this can be useful => https://github.com/vandadnp/flutter-tips-and-tricks/blob/main/tipsandtricks/canonicalized-maps-in-dart/canonicalized-maps-in-dart.md

374(Dec 29, 2022)

If you can turn a function into a data type, then you can extend it. This example shows how helpful this can be =>

https://github.com/vandadnp/flutter-tips-and-tricks/blob/main/tipsandtricks/extending-functions-in-flutter/extending-functions-in-flutter.md

373(Dec 1, 2022)

In order to make sure your stream produces an element every N-seconds, you can take advantage of this useful Stream transformer in Flutter / Dart => https://github.com/vandadnp/flutter-tips-and-tricks/blob/main/tipsandtricks/stream-timeout-between-events-in-flutter/stream-timeout-between-events-in-flutter.md

372(Nov 26, 2022)

Learn how to use reflection in Dart to fully describe any class https://github.com/vandadnp/flutter-tips-and-tricks/blob/main/tipsandtricks/dart-object-description-using-reflection/dart-object-description-using-reflection.md

371(Nov 24, 2022)

If you have multipel optional values which are needed for a single operation, you will need to check all of them for null and then perform your operation on them if all are non-null. Using this function you can simplify that task => https://github.com/vandadnp/flutter-tips-and-tricks/blob/main/tipsandtricks/unwrapping-multiple-optionals-in-flutter-and-dart/unwrapping-multiple-optionals-in-flutter-and-dart.md

370(Nov 19, 2022)

Dart's List leaves a lot to be desired from the default implementation. For instance if you read the first element of an empty list you get an exception. Rust and Swift have optionality baked into their lists so you receive optional values instead of exceptions. You can create your own lists in Dart though to circumvent some of these shortcomings. Here is an example => https://github.com/vandadnp/flutter-tips-and-tricks/blob/main/tipsandtricks/safelist-in-flutter-and-dart/safelist-in-flutter-and-dart.md

Contents

    ibhavikmakwana Useful Flutter and Dart Tips.
    Microsoft Collection of helpful tips and tricks for VS Code.
    rstacruz Tips and tricks in using Webpack
    Luur Swift tips and tricks
    me2beats Tips and tricks you should know when using Godot Engine!
    erluxman ❤️Awesome Flutter ❤️ tips and tricks ❤️
    fejes713 A curated collection of web accessibility tips, tricks, and best practices
    vandadnp Dart Optimization Tips and Tricks
    DanilaMihailov Read VimWiki tips locally from Vim
    justmarkham :robot::zap: Daily scikit-learn tips
    TuanNguyen2504 JavaScript Tips & Tricks
    praharshbhatt Flutter tips and tricks to make the development smoother and easier
    nisrulz :ballot_box_with_check: [Cheatsheet] Tips and tricks for Android Development
    github Tips, Tricks, and Resources for your hackathons.
    DrkSephy ES2015 [ES6] cheatsheet containing tips, tricks, best practices and code snippets
    ocean1 A curated list of practical tips and tricks to help you achieve an awesome CS master thesis [WIP] - contributions are welcome
    facontidavide Tips and tricks to optimize your C++ code
    ahmadawais 📟 NodeCLI.com repo with Node.js CLI best practices and production-ready tips & tricks.
    mgonzalezo Repository with some reference information about the CKA exam, tips & tricks and Reference URLs.
    voxpelli Tips and tricks for working with types in JavaScript
    phuoc-ng Super tiny, quick tips, tricks and best practices of front-end development
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