How to use VerticalListLayout with Feathers UI containers
The VerticalListLayout class may be used to position the children of a data container from top to bottom, in a single column that fills the entire width. Examples of data containers include ListView, TreeView, and GridView. This layout supports a number of useful options for adjusting the spacing around the container's children.
If all items in the layout should render with the exact same height, consider using
VerticalListFixedRowLayoutfor improved performance.
The Basics
Create a ListView container, set its data provider, and add it to the display list.
var container = new ListView();
container.dataProvider = new ArrayCollection([
{text: "A"},
{text: "B"},
{text: "C"}
]);
addChild(container);
Set the container's layout property to a new VerticalListLayout instance.
container.layout = new VerticalListLayout();
By default, the first child will be positioned in the top-left corner and fill the entire width of the container. Each additional child will be positioned below the previous child — creating a single, vertical column.
The following sections will introduce a number of properties that may be used to adjust the positioning and sizing of children in the layout.
Spacing
The padding is the space around the edges of the container that will contain no children. Padding may be added on each side, including top, right, bottom, and left.
layout.paddingTop = 10.0;
layout.paddingRight = 15.0;
layout.paddingBottom = 10.0;
layout.paddingLeft = 15.0;
If all four padding properties should be set to the same value, call the setPadding() method instead.
// sets top, right, bottom and left to the same value
layout.setPadding(10.0);
The gap refers to the space, measured in pixels, between each child in the container.
layout.gap = 5.0;
Number of rows
If the parent container does not have an explicit height value, the layout will calculate its ideal height automatically. To display a specific number of rows, regardless of the height of each row, set the requestedRowCount property.
layout.requestedRowCount = 4.0;
An integer value is not required, so a partial row may be made visible at the bottom of the list, if desired.
layout.requestedRowCount = 4.5;
If the container contains more children than the number of visible rows, the container will enable scrolling, if supported.