Prior to this change, the widgets that needed a `Clone` bound on `Message` to
implement the `Widget` trait could be created with a non-cloneable `Message`.
As a consequence, the compiler complained only when actually trying to use the
`Widget` trait. Normally, this happens when trying to `push` the widget in a
container or turn it into an `Element`.
Furthermore, the compiler error in this case does not mention `Message` nor the
`Clone` bound, but instead complains about a missing `From` implementation.
Thus, it can easily cause confusion!
This change introduces `Clone` bounds in the main implementation of the
widgets that need it to properly implement the `Widget` trait. As a
result, the compiler complains early when trying to create one of these widgets
with a non-cloneable `Message` and explicitly mentions that the `Message` needs
to implement `Clone`.
Both the native and the web slider now have a member `step` to control
the least possible change of the slider's value. It defaults to 1.0
for all sliders and can be adjusted with the step method.
Sliders for many color spaces update as any other sliders are moved
around. Color is space is clamped to sRGB, so Lab and Lch color spaces
cannot be fully expressed.
TODO:
- Real-time manipulation of base color to create a color scheme.
- Show slider value under each slider
- Show output values in text boxes for each color space
