Templates (ux:Template)

The ux:Template attribute in UX Markup, when placed on an XML element, specifies that the given XML element and its entire subtree is a template (Uno.UX.Template). Templates can construct an arbitrary number of copies of the UX Markup tree at runtime.

Syntax

<type ux:Template="template_name" />

Where type is any valid UX Markup type, and template_name is a valid Uno identifier.

Remarks

Templates are used in several contexts, most noticeably:

  • Inside an <Each> repeater, the content nodes are implicitly templates.
  • Inside a <Navigator>, page templates can be provided instead of regular nodes, to allow the Navigator to construct new copies of each page template on demand.

The ux:Name of the template instance

Inside node marked ux:Template, the current copy (instance) of the current template can be refered to by the template_name, the same way as if it was named the same way using ux:Name.

For example, in a contained <JavaScript> tag, we can refer to the template instance by name:

<Page ux:Template="homePage">
	<JavaScript>
		homePage.Parameter.onValueChanged(module, function() { ...

Also, in UX markup in general, we can use the page name in expressions:

<Page ux:Template="homePage">
	<Rectangle LayoutMaster="homePage" ... />

Using templates for component customizability

Templates can be used to increase the customizability of a component by allowing it to take custom elements to be used for its appearance. An example of this in action is the PageIndicator element, which spawns an element from a template for each page in a PageControl. An element is made a template by setting the ux:Template property to a key you want to identify that template by. This key is used by template accepting elements when looking for appropriate templates to draw.

Templates are drawn using Each. Each has a property called TemplateSource, which specifies the element from which Each gets its template. As mentioned before, templates identify themselves using a key. The key Each will look for a template with is specified using the TemplateKey property.

A common TemplateSource is a ux:Class the Each is a child of:

<StackPanel ux:Class="CoolRepeater" Background="#FAD">
	<Each TemplateSource="this" TemplateKey="Item" Count="20">
		<Text>Default template</Text>
	</Each>
</StackPanel>

This is a custom component which accepts a template, which it repeats 20 times. If no template is given, the Each will fallback to its default template: whatever is inside the Each. The custom component can then be used like this:

<CoolRepeater>
	<Text ux:Template="Item">Hello, world!</Text>
</CoolRepeater>