Change how the brightness applet and nightcolor KCM interacts
Status quo:
- In the KCM, I can select a night color schedule from: sunset, time of day, always on, always off.
- In the applet, I can turn a switch that enables the schedule, not night color itself.
Problems:
- I can temporarily disable night color when it's scheduled to be on, by turning off the switch in the applet. But I can't temporarily enable night color when it's scheduled to be off.
- So when a time-based schedule is in effect, and it's daytime, turning the switch seems to have no effect, which can be very confusing.
- When a night color schedule is selected, and the switch is off, the applet icon turns to a lightbulb crossed by a red line. It is wrong: a) the applet has other function - brightness control - so when night color is off, it should show the brightness icon. b) even if it should indicate that night color is off, the icon should be just the night color icon crossed.
Proposal:
- In the KCM, merge "always off" and "always on" into a "controlled manually" option.
- In the applet, the state of the switch should always reflect whether night color is currently in effect. Turning the switch should immediately enable/disable the night color effect, regardless of the schedule selected in KCM.
- The state of the switch should persist over sessions.
- The schedule selected in KCM should act as if it turns on / turns off the switch in the applet at the specified time (even if the machine is powered off then). It should not interfere with the user turning the switch manually.
- When night color is off, the tray icon should be "brightness", regardless of the schedule selected in KCM.
- The "night color" hotkey in kwin should be functionally identical to the switch in applet.
- Show a notification when a scheduled switch happens.
Edited by Jin Liu