Utilities
Background Size
The Background Size utility enables you to set the size of background images within UI elements.
Utility Class | USS Properties |
|---|---|
| bg-auto | background-size: auto; |
| bg-cover | background-size: cover; |
| bg-contain | background-size: contain; |
Basic Usage in UXML
Auto
This maintains the natural size of the image, preserving its original dimensions
<VisualElement class="bg-auto"></VisualElement>
Cover
This scales the image to cover the entire area of the element, potentially cropping the image to maintain its aspect ratio.
<VisualElement class="bg-cover"></VisualElement>
Contain
This scales the image to fit within the element’s area, ensuring that the entire image is visible without stretching or cropping.
<VisualElement class="bg-contain"></VisualElement>
Customize
Modifier Variations
You can customize which modifier variations of the Background Size utility are generated, such as pseudo-classes (e.g., hover, focus) and custom modifiers.
Background Size utility.By fine-tuning the utility variations, you maintain control over your stylesheet's size and complexity, ensuring that only necessary styles are included. To update these values:
- Open the Theme Config Asset: Find the asset within your Unity project.
- Navigate to the 'Utilities' Section: Locate the
Background Sizeutility. - Adjust Modifier Variations: Select which modifiers you want to be generated for the utility. Keep in mind that the order of the modifiers will affect the order and specificity of the generated USS classes.
Class Tags and Properties
The Background Size utility generates classes based on predefined tags and their associated USS properties. While we recommend keeping these defaults for consistency and ease of reference in our documentation, you have the option to customize them to suit your project's specific needs.
These values are prepended to the defined values in this format tag-{value}. If a tag is empty, the generated class will simply be the value by itself.
Here are the default tags and the USS properties they set for the Background Size utility:
- bg : background-size
To customize these tags and properties, you can edit the Tag Property Map field for the Background Size utility in the Theme Config asset. This allows you to define new tags or modify existing ones, thus tailoring the generated classes to your preferences.
Extending Core Fields
The Background Size utility does not extend any fields from the Core section of the Theme Config asset. Before you try to extend any fields, we recommend checking Unity's documentation to verify which types of values are expected by the relevant USS properties.
To customize or define these extended fields:
- Open the Theme Config Asset: Locate the asset within your Unity project.
- Navigate to the 'Utilities' Section: Find the
Background Sizeutility. - Customize Extend Fields: Modify or add fields in the
Extend Fieldsarray to change the core configuration values that are extended. You'll only be able to extend fields of the same type.
Disable Utility
The Background Size utility is enabled by default. You can disable it by unchecking the Enabled option in the Theme Config asset. This will prevent the generation of the utility's styles.