Class SingletonLayout

A concrete layout implementation which holds a single widget.

Notes

This class is useful for creating simple container widgets which hold a single child. The child should be positioned with CSS.

Hierarchy (view full)

Constructors

Properties

_widget: null | Widget = null

Accessors

  • get fitPolicy(): FitPolicy
  • Get the fit policy for the layout.

    Notes

    The fit policy controls the computed size constraints which are applied to the parent widget by the layout.

    Some layout implementations may ignore the fit policy.

    Returns FitPolicy

  • set fitPolicy(value): void
  • Set the fit policy for the layout.

    Notes

    The fit policy controls the computed size constraints which are applied to the parent widget by the layout.

    Some layout implementations may ignore the fit policy.

    Changing the fit policy will clear the current size constraint for the parent widget and then re-fit the parent.

    Parameters

    Returns void

  • get isDisposed(): boolean
  • Test whether the layout is disposed.

    Returns boolean

  • get parent(): null | Widget
  • Get the parent widget of the layout.

    Returns null | Widget

  • set parent(value): void
  • Set the parent widget of the layout.

    Notes

    This is set automatically when installing the layout on the parent widget. The parent widget should not be set directly by user code.

    Parameters

    Returns void

  • get widget(): null | Widget
  • Get the child widget for the layout.

    Returns null | Widget

  • set widget(widget): void
  • Set the child widget for the layout.

    Notes

    Setting the child widget will cause the old child widget to be automatically disposed. If that is not desired, set the parent of the old child to null before assigning a new child.

    Parameters

    Returns void

Methods

  • Attach a widget to the parent's DOM node.

    Parameters

    • widget: Widget

      The widget to attach to the parent.

      Notes

      This method is called automatically by the single layout at the appropriate time. It should not be called directly by user code.

      The default implementation adds the widgets's node to the parent's node at the proper location, and sends the appropriate attach messages to the widget if the parent is attached to the DOM.

      Subclasses may reimplement this method to control how the widget's node is added to the parent's node.

    Returns void

  • Detach a widget from the parent's DOM node.

    Parameters

    • widget: Widget

      The widget to detach from the parent.

      Notes

      This method is called automatically by the single layout at the appropriate time. It should not be called directly by user code.

      The default implementation removes the widget's node from the parent's node, and sends the appropriate detach messages to the widget if the parent is attached to the DOM.

      Subclasses may reimplement this method to control how the widget's node is removed from the parent's node.

    Returns void

  • A message handler invoked on an 'after-attach' message.

    Notes

    The default implementation of this method forwards the message to all widgets. It assumes all widget nodes are attached to the parent widget node.

    This may be reimplemented by subclasses as needed.

    Parameters

    Returns void

  • A message handler invoked on an 'after-detach' message.

    Notes

    The default implementation of this method forwards the message to all widgets. It assumes all widget nodes are attached to the parent widget node.

    This may be reimplemented by subclasses as needed.

    Parameters

    Returns void

  • A message handler invoked on an 'after-hide' message.

    Notes

    The default implementation of this method forwards the message to all non-hidden widgets. It assumes all widget nodes are attached to the parent widget node.

    This may be reimplemented by subclasses as needed.

    Parameters

    Returns void

  • A message handler invoked on an 'after-show' message.

    Notes

    The default implementation of this method forwards the message to all non-hidden widgets. It assumes all widget nodes are attached to the parent widget node.

    This may be reimplemented by subclasses as needed.

    Parameters

    Returns void

  • A message handler invoked on a 'before-attach' message.

    Notes

    The default implementation of this method forwards the message to all widgets. It assumes all widget nodes are attached to the parent widget node.

    This may be reimplemented by subclasses as needed.

    Parameters

    Returns void

  • A message handler invoked on a 'before-detach' message.

    Notes

    The default implementation of this method forwards the message to all widgets. It assumes all widget nodes are attached to the parent widget node.

    This may be reimplemented by subclasses as needed.

    Parameters

    Returns void

  • A message handler invoked on a 'before-hide' message.

    Notes

    The default implementation of this method forwards the message to all non-hidden widgets. It assumes all widget nodes are attached to the parent widget node.

    This may be reimplemented by subclasses as needed.

    Parameters

    Returns void

  • A message handler invoked on a 'before-show' message.

    Notes

    The default implementation of this method forwards the message to all non-hidden widgets. It assumes all widget nodes are attached to the parent widget node.

    This may be reimplemented by subclasses as needed.

    Parameters

    Returns void

  • A message handler invoked on a 'resize' message.

    Notes

    The layout should ensure that its widgets are resized according to the specified layout space, and that they are sent a 'resize' message if appropriate.

    The default implementation of this method sends an UnknownSize resize message to all widgets.

    This may be reimplemented by subclasses as needed.

    Parameters

    Returns void

  • A message handler invoked on an 'update-request' message.

    Notes

    The layout should ensure that its widgets are resized according to the available layout space, and that they are sent a 'resize' message if appropriate.

    The default implementation of this method sends an UnknownSize resize message to all widgets.

    This may be reimplemented by subclasses as needed.

    Parameters

    Returns void

  • Process a message sent to the parent widget.

    Parameters

    • msg: Message

      The message sent to the parent widget.

      Notes

      This method is called by the parent widget to process a message.

      Subclasses may reimplement this method as needed.

    Returns void

  • Remove a widget from the layout.

    Parameters

    • widget: Widget

      The widget to remove from the layout.

      Notes

      A widget is automatically removed from the layout when its parent is set to null. This method should only be invoked directly when removing a widget from a layout which has yet to be installed on a parent widget.

      This method does not modify the widget's parent.

    Returns void