2022-02-11
3007
#flutter
Eshiet Ekemini
43295
Feb 11, 2022 â‹… 10 min read

Flutter form validation: The complete guide

Eshiet Ekemini A graduate of University of Uyo and a tech enthusiast, Ekemini has been building for mobile for two years, with a particular focus on Kotlin and Flutter.

Recent posts:

Fix over-caching with dynamic IO caching in Next.js 15

Next.js 15 caching overhaul: Fix overcaching with Dynamic IO and the use cache directive.

David Omotayo
Aug 6, 2025 â‹… 10 min read
LLMs are facing a QA crisis here’s how we could solve it

LLMs are facing a QA crisis: Here’s how we could solve it

LLM QA isn’t just a tooling gap — it’s a fundamental shift in how we think about software reliability.

Rosario De Chiara
Aug 4, 2025 â‹… 7 min read

Windsurf vs. Cursor: When to choose the challenger

Windsurf AI brings agentic coding and terminal control right into your IDE. We compare it to Cursor, explore its features, and build a real frontend project.

Chizaram Ken
Jul 31, 2025 â‹… 9 min read

The CSS if() function: Conditional styling will never be the same

The CSS Working Group has approved the if() function for development, a feature that promises to bring true conditional styling directly to our stylesheets.

Ikeh Akinyemi
Jul 30, 2025 â‹… 12 min read
View all posts

4 Replies to "Flutter form validation: The complete guide"

  1. I got an error in the validation section then I solved the problem as follows;

    validator: (val) {
    if (!val.isValidName)
    return ‘Enter valid email’;
    },

    You cant return string or null in function, so you need to return empty string.If you do that it will solve.I did share code in the below

    validator: (val) {
    if (!val.isValidName)
    return ‘Enter valid email’;
    return ”;
    },

  2. Wow! So helpful in getting a handle on various validation and input field formatting in Flutter. Thank you! This is helpful and useful because it shows actual working examples, building from the basic form. The registration form is a particularly good example because it illustrates most use cases for starting programmers (in general, or just new to Flutter, like me).
    I’m not quite finished as I’ve got what I need for my current project, nonetheless I’m looking forward to the remainder (Making a custom form field, on). It really appears to fulfill on it’s title!

Leave a Reply