SelectListView

A scrollable list view for displaying selectable items in dropdown controls.

SelectListView provides a virtualized list interface for selecting from a collection of string options. It supports highlighting the current selection, null value handling, and automatic scrolling to selected items. The view uses a CollectionView for efficient rendering of large lists.

Key features:

• Virtualized scrolling for performance with large lists
• Current selection highlighting
• Support for null values with custom display text
• Click and touch interaction
• Automatic scrolling to selected items
• Customizable cell styling through themes

Usage example:

var listView = new SelectListView();
listView.list = ['Item 1', 'Item 2', 'Item 3'];
listView.nullValueText = 'None';
listView.value = 'Item 2';
listView.size(200, 150);
listView.onValueChange(this, (value, prev) -> {
    trace('Selected: ' + value);
});
add(listView);

Static Members #

Height of each item in the list in pixels

Instance Members #

Default is false, automatically set to true when any of this instance's observable variables has changed.

Custom theme override for this list view. If null, uses the global context theme

Whether to automatically scroll to the selected value when it changes

The currently selected value. Can be null if no value is selected

Array of string options to display in the list

Text to display for the null/empty value option. If null, no null option is shown

Scrolls the list to show the currently selected value.

Returns the total number of items in the list.

Includes an extra item if nullValueText is set to represent the null option.

Provides the frame (size and position) for an item at the given index.

All items have the same height (ITEM_HEIGHT) and fill the collection view width.

Called when a view is no longer needed at the given index.

Allows cleanup before view reuse. For SelectListView, cells can always be reused.

Creates or reuses a view for the item at the given index.

Creates CellView instances to display list items. Reuses existing views when possible for performance. Binds cell data and interaction handlers.

Creates a new SelectListView.

Sets up the collection view for virtualized scrolling, configures data binding, and initializes automatic scrolling behavior.

Private Members #

The collection view that handles virtualized scrolling and cell management

Event when any observable value as changed on this instance.

Event when theme field changes.

Event emitted when a value is clicked/selected

Event when value field changes.

Event when list field changes.

Event when nullValueText field changes.

Updates scroll position to show the current value if auto-scrolling is enabled.

This is called automatically when the value changes and autoScrollToValue is true.

Binds data and interaction handlers to a cell view.

Sets up automatic updates for cell content, selection state, and theme, and configures click handling for value selection.

Updates the visual style of the list view based on the current theme.

Sets the background color, border appearance, and other visual properties to match the current theme.

Metadata #