Button style attributes

Button presentation style attributes apply to BUTTON elements.

Note: This topic lists presentation style attributes for a specific class of form element, common presentation style attributes can also be used for this type of element.

alignment

Defines the position of the image and/or text inside a button, when the button is bigger than the content.

When both image and text are specified for a button, these will be combined as a single graphical element before applying the alignment style attribute. If the image and text render with different heights, the smallest element will be centered vertically to the element with the greatest height.

The value can be a combination of a vertical and horizontal alignment hints, separated by a space.

The value can also be "center", which is equivalent to "verticalCenter horizontalCenter".

Vertical alignment hints:
  • "top": anchor to the top edge.
  • "verticalCenter": center in middle.
  • "bottom": anchor to the bottom edge.
Horizontal alignment hints:
  • "left": anchor to the left edge.
  • "horizontalCenter": center in middle.
  • "right": anchor to the right edge.

The default is "center".

buttonType

Defines the rendering of a button.

Values can be:
  • "normal" (default): The button is rendered as a regular push button.
  • "link": the button is rendered as an HTML hyper-link. In contrast to the label hyper-link support, clicking on a "link" button does not start the default browser, but triggers the corresponding action, like a normal button.
Important: The buttonType Button style attribute cannot be changed dynamically, once the widget has been displayed.

scaleIcon

Defines the scaling behavior of the associated icon, if the source image size is bigger than the place reserved for it in the widget.

If the scaleIcon attribute is undefined, the behavior depends on the type of action view: toolbar button icons and action panel button icons are scaled down to match the size of the widget. For other widgets, by default no scaling occurs, as for scaleIcon="no".

Values can be:
  • "no": No scaling occurs and the image is taken as-is. It is up to the developer to resize the source image to avoid misalignment.
  • "yes": Images are scaled down following the height of the widget (button or edit field). Setting a big font can result in a big icon.

Independently of the scaleIcon attribute value,to avoid pixelization or blurring of images, raster images are never upscaled. However, SVG images and TTF icons can be upscaled without any penalty.

If the icon must be enlarged, the image is centered and a transparent border is added to "fill" the empty space. This allows a mix of larger and smaller icons while keeping widget alignment.

If scaling takes place, the aspect ratio of the original image is kept. A non-square source image displays as a non-square scaled icon.