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This interface is used on Microsoft Windows to control tab preview specific behavior.
Gecko 1.9.2
Inherits from: nsITaskbarPreview Last changed in Gecko 1.9.2 (Firefox 3.6 / Thunderbird 3.1 / Fennec 1.0)

Tab preview support is disabled by default in Gecko 1.9.2

Creating an nsITaskbarTabPreview for a window will automatically hide that window's nsITaskbarWindowPreview; this is done by Windows and cannot be prevented. When there are no more tab previews left for a window, the window preview is automatically made visible again.

An application may have as many tab previews as memory allows.

You can't directly instantiate this interface; instead, call the nsIWinTaskbar.createTaskbarTabPreview().

Method overview

void EnsureRegistration(); Violates the XPCOM interface guidelines
nativeWindow GetHWND(); Violates the XPCOM interface guidelines
void move(in nsITaskbarTabPreview aNext);


Attribute Type Description
icon imgIContainer The icon displayed next to the title in the preview. This is null by default.
title DOMString The title displayed above the thumbnail. By default, this is an empty string.


Violates the XPCOM interface guidelines


Used internally to ensure that the taskbar knows about this preview. If a preview is not registered, the API call to set its sibling (via the move() method) will fail silently.

This method is only invoked when it's safe to make taskbar API calls.

void EnsureRegistration();


Violates the XPCOM interface guidelines


Used internally to obtain the handle to the proxy window for the preview.

nativeWindow GetHWND();


Return value

The HWND for the preview's proxy window.


Relocates the preview relative to another tab preview from the same window.

void move(
  in nsITaskbarTabPreview aNext
The preview that this preview should be placed to the left of. A value of null indicates that this preview should be the rightmost one.

See also