Name Description Size
content
CustomizableUI.sys.mjs gPanelsForWindow is a list of known panels in a window which we may need to close should command events fire which target them. 12040
moz.build 401
PanelMultiView.sys.mjs Allows a popup panel to host multiple subviews. The main view shown when the panel is opened may slide out to display a subview, which in turn may lead to other subviews in a cascade menu pattern. The <panel> element should contain a <panelmultiview> element. Views are declared using <panelview> elements that are usually children of the main <panelmultiview> element, although they don't need to be, as views can also be imported into the panel from other panels or popup sets. The panel should be opened asynchronously using the openPopup static method on the PanelMultiView object. This will display the view specified using the mainViewId attribute on the contained <panelmultiview> element. Specific subviews can slide in using the showSubView method, and backwards navigation can be done using the goBack method or through a button in the subview headers. The process of displaying the main view or a new subview requires multiple steps to be completed, hence at any given time the <panelview> element may be in different states: -- Open or closed All the <panelview> elements start "closed", meaning that they are not associated to a <panelmultiview> element and can be located anywhere in the document. When the openPopup or showSubView methods are called, the relevant view becomes "open" and the <panelview> element may be moved to ensure it is a descendant of the <panelmultiview> element. The "ViewShowing" event is fired at this point, when the view is not visible yet. The event is allowed to cancel the operation, in which case the view is closed immediately. Closing the view does not move the node back to its original position. -- Visible or invisible This indicates whether the view is visible in the document from a layout perspective, regardless of whether it is currently scrolled into view. In fact, all subviews are already visible before they start sliding in. Before scrolling into view, a view may become visible but be placed in a special off-screen area of the document where layout and measurements can take place asynchronously. When navigating forward, an open view may become invisible but stay open after sliding out of view. The last known size of these views is still taken into account for determining the overall panel size. When navigating backwards, an open subview will first become invisible and then will be closed. -- Active or inactive This indicates whether the view is fully scrolled into the visible area and ready to receive mouse and keyboard events. An active view is always visible, but a visible view may be inactive. For example, during a scroll transition, both views will be inactive. When a view becomes active, the ViewShown event is fired synchronously, and the showSubView and goBack methods can be called for navigation. For the main view of the panel, the ViewShown event is dispatched during the "popupshown" event, which means that other "popupshown" handlers may be called before the view is active. Thus, code that needs to perform further navigation automatically should either use the ViewShown event or wait for an event loop tick, like BrowserTestUtils.waitForEvent does. -- Navigating with the keyboard An open view may keep state related to keyboard navigation, even if it is invisible. When a view is closed, keyboard navigation state is cleared. This diagram shows how <panelview> nodes move during navigation: In this <panelmultiview> In other panels Action ┌───┬───┬───┐ ┌───┬───┐ │(A)│ B │ C │ │ D │ E │ Open panel └───┴───┴───┘ └───┴───┘ ┌───┬───┬───┐ ┌───┬───┐ │{A}│(C)│ B │ │ D │ E │ Show subview C └───┴───┴───┘ └───┴───┘ ┌───┬───┬───┬───┐ ┌───┐ │{A}│{C}│(D)│ B │ │ E │ Show subview D └───┴───┴───┴───┘ └───┘ │ ┌───┬───┬───┬───┐ ┌───┐ │ │{A}│(C)│ D │ B │ │ E │ Go back │ └───┴───┴───┴───┘ └───┘ │ │ │ │ │ └── Currently visible view │ │ │ └───┴───┴── Open views 62267