Context menu on hover / clickable tooltips

[emilk]

It would be great to be able to bring up a context menu just by hovering an element. It would act similar to a tooltip, but a tooltip you can interact with (it won't go away when you move the mouse).

[mankinskin]

For anyone looking into implementing this, this would probably be an abstraction over the trigger mechanism for bringing up a stationary menu, i.e. a menu created at some other element (represented by response):

egui/egui/src/menu.rs

Lines 284 to 308 in 2d2022f

	if (response.clicked() && root.is_menu_open(id)) || input.key_pressed(Key::Escape) {
	// menu open and button clicked or esc pressed
	return MenuResponse::Close;
	} else if (response.clicked() && !root.is_menu_open(id))
	|| (response.hovered() && root.is_some())
	{
	// menu not open and button clicked
	// or button hovered while other menu is open
	let pos = response.rect.left_bottom();
	return MenuResponse::Create(pos, id);
	} else if input.pointer.any_pressed() && input.pointer.primary_down() {
	if let Some(pos) = input.pointer.interact_pos() {
	if let Some(root) = root.inner.as_mut() {
	if root.id == id {
	// pressed somewhere while this menu is open
	let menu_state = root.menu_state.read();
	let in_menu = menu_state.area_contains(pos);
	if !in_menu {
	return MenuResponse::Close;
	}
	}
	}
	}
	}
	MenuResponse::Stay

you can see that a menu is already opened by hovering if another menu is open already (L288).

the menu doesn't really have a mechanism for configuring it yet, but I suppose this could be easily added with some enums and a MenuConfig struct or something like that. Would be great if all these behaviours could be configured.

[apexys]

It would also be interesting to be able to open a context menu with a left click or through some other action programmatically.

[emilk]

This could also be implemented as "Tooltips stay put when you move the mouse onto them"

[YgorSouza]

This could also be seen as a Window that is anchored to a Response and closes when you click outside it, like the solution proposed for #4463. This is called a Popup in other UI libraries, but egui already uses popup to refer to the ComboBox drawer.

[emilk]

Follow-up issue:

• Unify menus with tooltips/popups #4607