Associating RETURN key with a button in Fyne

by

Summary

The issue at hand is associating the RETURN key with a button in a Fyne application, specifically when using widget.NewForm to create a login form. The goal is to allow users to submit the form by pressing the RETURN key, rather than requiring a mouse click on the Submit button.

Root Cause

The root cause of this issue is that the default behavior of the RETURN key in Fyne is not to submit the form when the focus is on a text entry field. Instead, it typically moves the focus to the next field or widget. The fact that widget.NewForm hides the underlying buttons makes it more complicated to directly associate the RETURN key with the Submit function.

Why This Happens in Real Systems

This issue occurs in real systems due to the following reasons:

  • Default widget behavior: Fyne widgets have default behaviors that may not always align with the desired application behavior.
  • Limited direct access to underlying widgets: When using high-level widgets like widget.NewForm, direct access to the underlying buttons or fields may be limited, making it harder to customize their behavior.
  • Focus management: Managing focus between different widgets and fields can be complex, especially when trying to override default behaviors.

Real-World Impact

The real-world impact of this issue includes:

  • Poor user experience: Requiring users to click the Submit button with the mouse can be frustrating and less intuitive than simply pressing the RETURN key.
  • Inconsistent behavior: If the application behaves differently from what users expect (e.g., pressing RETURN does not submit the form), it can lead to confusion and a negative user experience.
  • Accessibility concerns: For users who rely heavily on keyboard navigation, not being able to submit a form with the RETURN key can be a significant accessibility issue.

Example or Code

package main

import (
    "fyne.io/fyne/v2"
    "fyne.io/fyne/v2/app"
    "fyne.io/fyne/v2/container"
    "fyne.io/fyne/v2/widget"
)

func main() {
    a := app.New()
    w := a.NewWindow("Login")

    idValue := widget.NewEntry()
    pwValue := widget.NewPasswordEntry()

    loginForm := widget.NewForm(
        widget.NewFormItem("Username", idValue),
        widget.NewFormItem("Password", pwValue),
    )

    loginForm.OnCancel = func() { w.Close() }
    loginForm.OnSubmit = func() { 
        // Submit logic here
        w.Close() 
    }

    w.SetContent(loginForm)
    w.Canvas().Focus(idValue)

    w.ShowAndRun()
}

How Senior Engineers Fix It

Senior engineers fix this issue by:

  • Understanding the widget hierarchy: Knowing how widgets are structured and interact with each other.
  • Customizing widget behavior: Using available APIs or extending widgets to change their default behavior.
  • Implementing custom focus management: Controlling how focus moves between widgets to achieve the desired behavior.
  • Testing for accessibility and user experience: Ensuring that the solution works well for all users, including those with accessibility needs.

Why Juniors Miss It

Junior engineers might miss this issue due to:

  • Lack of experience with widget customization: Not being familiar with how to extend or modify widget behavior.
  • Insufficient understanding of focus management: Not fully grasping how focus works between widgets and how to control it.
  • Overlooking accessibility and user experience: Focusing too much on functional requirements and neglecting how the application behaves from a user’s perspective.