Disabled Indeterminate Checkbox Styling

[RussellAFisher]

Bug: Background-color styling for a disabled indeterminate checkbox doesn't match styling for disabled checked checkbox

What is the expected behavior?

Disabled checkboxes all have the same background-color: #b0b0b0 no matter their state

What is the current behavior?

Indeterminate checkboxes retain their themed color

What are the steps to reproduce?

https://stackblitz.com/edit/angular-iscw2w

1. Expand top level
2. Click on a secondary level checkbox so top level becomes indeterminate
3. Click disable button at the bottom

What is the use-case or motivation for changing an existing behavior?

Regression from 6

Which versions of Angular, Material, OS, TypeScript, browsers are affected?

"@angular/core": "^7.1.1",
"@angular/material": "^7.1.1",
"typescript": "~3.1.6"
MacOS High Sierra 10.13.6
Chrome Version 70.0.3538.110

Is there anything else we should know?

[crisbeto]

This matches the Material Design spec. See:

[RussellAFisher]

@crisbeto Thank you, I'm curious why did this change from 6 to 7? And whats the purpose of keeping the background-color rather then going gray like disabled selected?

[jwdepetro]

@crisbeto Any reason why this changed from 6 to 7?

[crisbeto]

The reason was that the Material Design spec changed and we are matching it. @RussellAFisher I'm not sure what the reasoning is, but it seems to be deliberate when looking at the spec.

[michelled66]

@crisbeto I think the question is why did the Material Design spec change? The "check" versus "minus" seems determinate enough to differentiate between "Selected" and "Indeterminate"
Now a UI will have a visual inconsistency that may confuse a user when the view is disabled. Meaning, a user might equate gray with disabled but then see a muted color for some options and become unsure if the option is enabled or disabled.

[crisbeto]

I'm sorry, I just double-checked it with the people that are maintaining the design spec and according to them all disabled checkboxes are supposed to be greyed out. It looks like an incorrect design got uploaded to the site which we ended up implementing.

[RussellAFisher]

@crisbeto Thank you for looking into this, much appreciated.

[michelled66]

@crisbeto Thank you!