LuaAPI/types/widget

The widget userdata offers access to a widget of a GUI2 dialog. While there is only one type of widget userdata that covers all widgets including the window itself, the properties of a widget userdata are different for each type of widget. Indexing a widget's userdata can either be used to access a child widget or to set or get a property of a widget. Some properties are read-only; the properties depend on the type of the widget.

An example of accessing a child widget:

function preshow(dialog)
  local okay_button = dialog.okay_button
  -- okay_button is now a handle to the the widgets child with the id 'okay_button' 
end

Widget Attributes

selected

• widget.selected ↔ boolean
• [toggle_button], [toggle_panel]

Whether the item is selected or not.

selected_index

• widget.selected_index ↔ index
• [listbox], [multi_page], [stacked_widget], selectable_item ([menu_button], [toggle_button], [toggle_panel])

The selected index of the item.

text

• widget.text ↔ text
• [text_box]

The text of the textbox.

value

• widget.value ↔ position
• [slider]

percentage

• widget.percentage ↔ position
• [progress_bar]

selected_item_path

• widget.selected_item_path → array of indices
• [slider]

A table describing the currently selected node. If for example, in the following treeview. Item 9 is selected, the result will be {2,1,3}.

+Section1
 +Subsection11
  *Item1
  *Item2
  *Item3
 +Subsection12
  *Item4
  *Item5
  *Item6
+Section2
 +Subsection21
  *Item7
  *Item8
  *Item9
 +Subsection22
  *Item10
  *Item11
  *Item12

path

• widget.path → array of indices
• [tree_view_node]

See selected_item_path for the syntax.

unfolded

• widget.unfolded ← boolean
• [tree_view_node]

unit

• widget.unit ← unit or unit type
• [unit_preview_pane]

item_count

• widget.item_count → number of items
• [multi_page], [listbox]

use_markup

• widget.use_markup → boolean
• most widgets, in particular [label], [button]

label

• widget.label ← text
• most widgets, in particular [label], [button], [image]

The label, technically this is a special string used in the widgets wml definition. It usually does what one would expect, but also sets the image for [image] widgets.

marked_up_text

• widget.marked_up_text ← text
• most widgets, in particular [label], [button]

Shortcut for setting label and use_markup=yes.

enabled

• widget.enabled ← boolean
• all widgets

tooltip

• widget.tooltip ← text
• all widgets

visible

• widget.visible ← visibility string
• all widgets

The following visibility statuses are recognized:

String value	Boolean shorthand	Meaning
visible	true	The widget is visible and handles events.
hidden		The widget is not visible, doesn't handle events, but still takes up space on the dialog grid.
invisible	false	The widget is not visible, doesn't handle events, and does not take up space on the dialog grid.

type

• widget.type → string
• all widgets

widget callbacks

on_modified

• widget.on_modified ← function
• all widgets the allow the user to select a value of any type.

on_left_click

• widget.on_left_click ← function
• all widgets

on_button_click

• widget.on_button_click ← function
• button type widgets

widget methods

focus

• widget:focus()

Switches the keyboard focus to the widget. This is often useful for dialogs containing a central listbox, so that it can be controlled with the keyboard as soon as it is displayed.

set_canvas

• widget:set_canvas(layer index, content)

Sets the WML passed as the second argument as the canvas content (index given by the first argument) of the widget. The content of the WML table is described at GUICanvasWML.

-- draw two rectangles in the upper-left corner of the window (assume dialog is the window widget)
dialog:set_canvas(2, {
    wml.tag.rectangle { x = 20, y = 20, w = 20, h = 20, fill_color= "0,0,255,255" },
    wml.tag.rectangle { x = 30, y = 30, w = 20, h = 20, fill_color = "255,0,0,255" }
})

The meaning of the canvas index depends on the chosen widget. It may be the disabled / enabled states of the widget, or its background / foreground planes, or... For instance, overwriting canvas 1 of the window with an empty canvas causes the window to become transparent.

add_item

• widget:add_item() → the new item

Add an item to a widget, for example a listbox. Returns the created item as a widget userdata.

add_item_of_type

• widget:'add_item_of_type(category) → the new item

Add an item to a widget which is a heterogeneous container of different types of widgets, in particular multi_pages and treeviews.

remove_items_at

• widget:'remove_items_at(position)

Removes the widget at the given index of a container type widget (like treeviews).

find

• widget:find(path, to, widget)

Finds a child widget of the widget of the given path. For example, here it searches for the widget with the id 'preview_panel' of the second item of the widget with the id 'unit_list'