Construct a new layout.
Private _widgetGet the fit policy for the layout.
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.
Set the fit policy for the layout.
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.
Test whether the layout is disposed.
Get the parent widget of the layout.
Set the parent widget of the layout.
This is set automatically when installing the layout on the parent widget. The parent widget should not be set directly by user code.
Get the child widget for the layout.
Set the child widget for the layout.
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.
Protected attachAttach a widget to the parent's DOM node.
The widget to attach to the parent.
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.
Protected detachDetach a widget from the parent's DOM node.
The widget to detach from the parent.
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.
Protected initProtected onA message handler invoked on an 'after-attach' message.
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.
Protected onA message handler invoked on an 'after-detach' message.
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.
Protected onA message handler invoked on an 'after-hide' message.
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.
Protected onA message handler invoked on an 'after-show' message.
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.
Protected onA message handler invoked on a 'before-attach' message.
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.
Protected onA message handler invoked on a 'before-detach' message.
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.
Protected onA message handler invoked on a 'before-hide' message.
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.
Protected onA message handler invoked on a 'before-show' message.
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.
Protected onA message handler invoked on a 'child-hidden' message.
The default implementation of this handler is a no-op.
Protected onA message handler invoked on a 'child-removed' message.
This will remove the child widget from the layout.
Subclasses should not typically reimplement this method.
Protected onA message handler invoked on a 'child-shown' message.
The default implementation of this handler is a no-op.
Protected onProtected onA message handler invoked on a 'resize' message.
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.
Protected onA message handler invoked on an 'update-request' message.
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.
Remove a widget from the layout.
The widget to remove from the layout.
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.
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.