Changes for Window_GadgetMouseScroll
Window_GadgetMouseScroll (0x82892) is generated by a limited set of gadgets on request in their gadget flags word. The flag to enable the report is labelled *_GenerateMouseScroll. Whilst it uses the phrase MouseScroll, the event is generated by any alternate pointer device operation whilst over that gadget and may in addition be generated by other, equivalent operations.
The event is generated to inform applications that the user has scrolled over one of the gadgets.
The Writable Field gadget supports Writable_GenerateMouseScroll (flag 0x20) to generate the scroll notification. The gadget will also generate the new event when Page up/Page down are used.
Display field gadget
The Display Field gadget supports DisplayField_GenerateMouseScroll (flag 0x8) to generate the scroll notification.
The NumberRange gadget does not generate the Window_GadgetMouseScroll event, but sets the flags on the Display and Writable field gadgets and consumes the event generated. The gadget is modified by the step specified for the gadget adjusters.
In addition the slider is now marked as being draggable (or scrollable) when it has adjusters or a writable field. In the past the slider was only draggable (or scrollable) when it had a writable field. A true display only number-range slider is now only possible when both the Writable and Adjusters flags are clear.
PopUp Menu gadget
The PopUp menu gadget supports PopUp_GenerateMouseScroll (flag 0x2) to generate scroll notifications. It does not manipulate the menu (or other object associated with the gadget) it triggers.
The NumberRange gadget does not generate the Window_GadgetMouseScroll event but sets the flags on the PopUp, Display and Writable field gadgets and consumes the event generated. The value displayed (if any) is modified by the scroll.
Option Button gadget
The Option Button gadget supports OptionButton_GenerateMouseScroll (flag 0x8) to generate the scroll notification.
Radio Button gadget
The Radio Button gadget supports RadioButton_GenerateMouseScroll (flag 0x8) to generate the scroll notification.
The Draggable gadget supports Draggable_GenerateMouseScroll (flag 0x200) to generate the scroll notification. Note that this form of notification is not presently supported on gadgets which use a private sprite area.
The Adjuster gadget supports Adjuster_GenerateMouseScroll (flag 0x4) to generate the scroll notification.
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