Fix MacosThemeData to properly apply user-defined component theme classes.

[whiplashoo]

Fixes an issue where user-defined theme properties pushButtonTheme, helpButtonTheme, and tooltipTheme were not passed properly when creating a custom MacosThemeData.

Now, a user can customize a theme like this:

return MacosApp(
  darkTheme: MacosThemeData.dark().copyWith(
    pushButtonTheme: const PushButtonThemeData().copyWith(
      color: MacosColors.appleBrown,
      disabledColor: MacosColors.applePurple,
      secondaryColor: MacosColors.appleMagenta,
    ),
    helpButtonTheme: const HelpButtonThemeData(
      color: MacosColors.appleOrange,
      disabledColor: MacosColors.appleCyan,
    ),
    tooltipTheme: const TooltipThemeData(
      height: 100.0,
    ),
  ),
)

and get properly styled PushButton, HelpButton, and MacosTooltip (not shown) widgets:

Also changed a couple of colors in the example/main.dart, to remove its Material library dependency.

Pre-launch Checklist

• I have run dartfmt on all changed files
• I have incremented the package version as appropriate and updated CHANGELOG.md with my changes
• I have added/updated relevant documentation
• I have run "optimize/organize imports" on all changed files
• I have addressed all analyzer warnings as best I could

[whiplashoo]

Got a couple of failing tests, will check again.

[whiplashoo]

OK, there is also another issue with the components' ThemeData classes, that caused these tests to fail with null-check errors.

These occur when a user defines the PushButtonThemeData for the theme without explicitly setting all of its constructor properties. For example, trying to customize only the color of PushButtons via the theme:

theme: MacosThemeData.light().copyWith(
  pushButtonTheme: PushButtonThemeData(
    color: MacosColors.appleOrange,
  ),
),

causes a CastError (null-check) on Line 232, because disabledColor ends up being null (and another one later, because secondaryColor also ends up being null).

I believe we want the user to be able to set just color and not have to explicitly set the other two properties to their default values. The same happens with helpButtonTheme, tooltipTheme, macosIconButtonTheme, macosPopupButtonTheme.

One solution would be to provide the default colors inside the widgets as well, via theme-level properties. This is how Flutter's material theme does it, for example on FloatingActionButtons:

final Color foregroundColor = this.foregroundColor
  ?? floatingActionButtonTheme.foregroundColor
  ?? theme.colorScheme.onSecondary;
final Color backgroundColor = this.backgroundColor
  ?? floatingActionButtonTheme.backgroundColor
  ?? theme.colorScheme.secondary;
final Color focusColor = this.focusColor
  ?? floatingActionButtonTheme.focusColor
  ?? theme.focusColor;

This would require to populate MacosThemeData with more top-level properties, and then just initialize the component themes without setting anything.

[GroovinChip]

@whiplashoo I'm also seeing these failing tests. The problem is coming from the fact that in our tests we are not passing any values to the theme classes. See for example line 22 of push_button_test.dart. When pass values to the theme data class, the test passes.

[GroovinChip]

All tests should pass now.

[codecov]

Codecov Report

Merging #182 (f661b99) into dev (f82570a) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##              dev     #182   +/-   ##
=======================================
  Coverage   62.66%   62.66%           
=======================================
  Files          33       33           
  Lines        3337     3337           
=======================================
  Hits         2091     2091           
  Misses       1246     1246           

Impacted Files	Coverage Δ
lib/src/theme/macos_theme.dart	54.95% <100.00%> (ø)

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[whiplashoo]

Indeed, the tests should pass now. However, I am still seeing the null-check error, when initializing a PushButtonTheme with just one property, like:

theme: MacosThemeData.light().copyWith(
  pushButtonTheme: PushButtonThemeData(
    color: MacosColors.appleOrange,
  ),
),

Am I missing something?

[GroovinChip]

@whiplashoo I'll look into it

[GroovinChip]

I'm thinking the problem is we are missing merge() methods for MacosThemeData and various widget ThemeData classes. See here and here for examples

[whiplashoo]

OK, that looks doable. I will try to work on it soon.

[GroovinChip]

OK, that looks doable. I will try to work on it soon.

Thanks!