<layout>
Abstract layout base class.
This layout class is the base class that all other layouts —
such as, for example <simplelayout> and
<resizelayout> — extend.
A layout arranges the views within the element that it is attached
to. simplelayout is one example of a basic
extension of this layout object, and the code sample below illustrates
its use.
For example, the layout in:
<canvas height="30">
<view>
<text>A</text>
<text>B</text>
<simplelayout axis="y"/>
</view>
</canvas>
is necessary to keep the A and B text views from being positioned
on top of each other. As an alternative to the
<layout> element, a view may specify a
layout attribute. For example, the previous
example is equivalent to:
<canvas height="30">
<view layout="axis: y">
<text>A</text>
<text>B</text>
</view>
</canvas>
You do not use <layout> to explicitly position
views. Rather, you may extend this class to create new types of
layouts.
Layouts, like constraints and animators, affect specific attributes of a view. Views can have more than one layout, as long as each set of attributes
associated with a layout does not overlap with any of the other sets.
| Attributes |
| Name |
Usage |
Type (Tag) |
Type (JS) |
Default |
Category |
| delegates |
JS only |
|
Array of LzDelegate |
|
readonly |
| |
An array of all the delegates used by the
layout |
|
| locked |
Tag & JS |
boolean |
Boolean |
|
setter |
| |
Set to true if layout is locked from updates. |
|
| subviews |
JS only |
|
Array of LzView |
|
readonly |
| |
Array holding the views under this layout's
control. |
|
| updateDelegate |
JS only |
|
LzDelegate |
|
readonly |
| |
A delegate used to update the layout. |
|
| view.layouts |
JS only |
|
|
|
readonly |
| |
If it doesn't already exist, layouts create an array
in the view that it attaches to that hold the list of layouts attached
to the view. |
|
Attributes inherited from
Node
class, classroot, cloneManager, datapath, defaultplacement, id, ignoreAttribute, ignoreplacement, immediateparent, initstage, name, nodeLevel, onconstruct, oninit, parent, placement, subnodes
Methods
| addSubview() |
| LzLayout.addSubview(sd) |
|
Called whenever a new subview is added to the layout. This is called both
in the layout constructor and when a new subview is called after layout
has been created. This is only called if the view's "ignorelayout" option is
not set.
|
| Parameters |
| Name |
Type |
Desc |
| sd |
LzView |
The subview to add. |
|
| ignore() |
| LzLayout.ignore(s) |
|
Called when a subview is to be ignored by the layout. By default, most
layouts include all the subviews of a given view.
|
| Parameters |
| Name |
Type |
Desc |
| s |
LzView |
The subview to ignore. |
|
| lock() |
| LzLayout.lock() |
|
Lock the layout from processing updates. This allows the layout to register
for events that it generates itself. Unfortunately, right now all subclass
routines that can generate calls that may result in the layout calling
itself should check the lock before processing. Failure to do so is not
catastrophic, but it will slow down your program.
|
|
| releaseLayout() |
| LzLayout.releaseLayout() |
|
Remove the layout from the view and unregister the delegates that the layout
uses.
|
|
| removeSubview() |
| LzLayout.removeSubview(sd) |
|
Called when a subview is removed. This is not well tested.
|
| Parameters |
| Name |
Type |
Desc |
| sd |
LzView |
The subview to be removed. |
|
| reset() |
| LzLayout.reset(e) |
|
Reset any held parameters (such as kept sizes that may have changed) and
before updating.
|
| Parameters |
| Name |
Type |
Desc |
| e |
Any |
The event data that is passed by the delegate that called this
funciton. This is usually unused, since more than one type of delegate can
call reset. |
|
| setLayoutOrder() |
| LzLayout.setLayoutOrder(sub1, sub2) |
|
Reorder the second subview given to this function so that it immediately
follows the first. Doesn't touch the placement of the first subview given
|
| Parameters |
| Name |
Type |
Desc |
| sub1 |
LzView |
The reference subview which the second subview should
follow in the layout order. Alternatively, can be "first" or "last" |
| sub2 |
LzView |
The subview to be moved after the reference subview. |
|
| swapSubviewOrder() |
| LzLayout.swapSubviewOrder(sub1, sub2) |
|
Swap the positions of the two subviews within the layout
|
| Parameters |
| Name |
Type |
Desc |
| sub1 |
LzView |
The reference subview which the second subview should
follow in the layout order. |
| sub2 |
LzView |
The subview to be moved after the reference subview. |
|
| unlock() |
| LzLayout.unlock() |
|
Unlock the layout once update is done.
|
|
animate, applyConstraint, applyData, childOf, completeInstantiation, construct, createChildren, dataBindAttribute, destroy, determinePlacement, getAttribute, getOption, getUID, init, lookupSourceLocator, searchImmediateSubnodes, searchSubnodes, setAttribute, setDatapath, setID, setName, setOption
Copyright © 2002-2005 Laszlo Systems, Inc.
All Rights Reserved. Unauthorized use, duplication or
distribution is strictly prohibited. This is the proprietary
information of Laszlo Systems, Inc. Use is subject to license terms.
