proposal: missing_alt_text

[gregorscholz]

missing_alt_name

Description

Image widget should be accessible for everybody and therefore contain an alt text.

Details

For vision impaired people images can be annoying, they often use screen readers to get the information on the page. To also get information about the images, Image widgets should contain a semanticLabel.

Bad Examples

Image(
    image: AssetImage('user_profile_picture'),
),

Good Examples

Image(
    image: AssetImage('user_profile_picture'),
    semanticLabel: 'profile picture',
),

Discussion

With a semanticLabel added, people using screen readers can get a better overview of what information is displayed on the screen. We as a community want to be open for everybody as much as we want be build applications which are accessible for everyone.

Also mentioned here: 2300

[srawlins]

CC @goderbauer

[lrhn]

If this is as important as this, should the parameter be made required directly in Flutter instead?

[IchordeDionysos]

@lrhn might prompt users just to put an empty string which is even worse because an empty string indicates to screen readers that an image is just a decorative image.

And it would make it nearly impossible for automated A11y checks to distinguish whether an alt text is missing or just omitted for decorative images.

[lrhn]

I can see the argument that you may omit alt-texts during development, but want to be reminded to add them before release. A warning is better for that than an error.

(Should we have a way to make a parameter recommended, so it's a warning to not pass it, but not an error? Or only optional in development mode, not production.?)

[gregorscholz]

I would also vote for it beeing a warning instead of an error.