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This interface is used on Microsoft Windows as a common interface for both window and tab taskbar previews.
Gecko 1.9.2
Inherits from: nsISupports Last changed in Gecko 1.9.2 (Firefox 3.6 / Thunderbird 3.1 / Fennec 1.0)

You can not directly instantiate this interface. Instead, you use nsITaskbarTabPreview or nsITaskbarWindowPreview as appropriate.

Method overview

void invalidate();


Attribute Type Description
active boolean Indicates whether or not the preview is marked as active (currently selected) in the taskbar.
controller nsITaskbarPreviewController

The controller for this preview. The controller provides the behavior and appearance for the taskbar preview, and is responsible for determining the size and contents of the preview, which buttons are displayed, and how the application responds to user actions on the preview. The controller is not allowed to be null.

Note:  Neither nsITaskbarTabPreview or nsITaskbarWindowPreview makes full use of the controller; see the documentation for each interface for details on which controller methods are used.
tooltip DOMString A string containing the text displayed in the tooltip above the preview when the user hovers over it. By default, this is an empty string.
visible boolean

Indicates whether or not the preview is visible; by default, this is false.

Note: Changing this value is computationally expensive for tab previews, because doing so causes the proxy window to be destroyed and rebuilt, then re-registered with the taskbar. If any step of that process fails, an exception is thrown. For window previews, changing this value is computationally trivial.



Invalidates the taskbar's cached image of the preview, forcing a redraw if necessary.

void invalidate();


See also