baselist

baselist
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Description

This class is a container for a group of baselistitems. To use baselist, baselistitem must be subclassed to provide a visual representation of the list item. It supports single select by default. Set multiselect to true to allow multiple selection (shift-click for a range, control-click for an arbitrary set).

Contained list items may be declared inside the list, such as:

            <canvas height="100">
              <baselist layout="axis:y;spacing:2">
                <baselistitem height="15" width="25" bgcolor="${selected ? 0xffff00 : 0x0000ff}"/>
                <baselistitem height="15" width="50" bgcolor="${selected ? 0xffff00 : 0x0000ff}"/>
                <baselistitem height="15" width="100" bgcolor="${selected ? 0xffff00 : 0x0000ff}"/>
              </baselist>
              <text y="70">Click bar to select it.</text>
            </canvas>

or replicated from data:

            <canvas height="70">
             <dataset name="items">
                <item>one</item>
                <item>two</item>
                <item>three</item>
              </dataset>
            
              <class name="myitem" extends="baselistitem"
                     bgcolor="${selected ? yellow : white}">
                 <attribute name="text" type="text"/>
                 <method name="applydata" args="d">
                     setAttribute('text', d);
                 </method>
                 <text text="${parent.text}"/>
              </class>
            
              <baselist layout="axis:y; spacing:2">
                <myitem datapath="items:/item/text()"/>
              </baselist>
              <text y="70" >Click on a number to select it.</text>
             </canvas>

Optimizing Lists

If your lists represent data from a datapath, there are two optimizations that you may want to consider:

pooling: If you will be changing the data that is represented by the list after it has been created, you can set dataoption="pooling". For more about pooling see the datapath pooling attribute and the example in list.
lazy: If there are more items in the list than will be visible and all list items are the same size (for example, in a scrolling list or combobox), you should set dataoption="lazy". For more about lazy replication see the datapath replication attribute, LzLazyReplicationManager, and the example in list.

An abstract class which all list components should subclass.

Superclass Chain

node (LzNode) » view (LzView) » basecomponent » basevaluecomponent » baseformitem » baselist

Known Subclasses

Known Direct Subclasses: basetabsbar, basetabslider, list, radiogroup

Details

Properties (5)

dataoption: <attribute name="dataoption" type="string" value="none" />

public var dataoption : String;

One of "lazy", "resize", "pooling", "none".
defaultselection: <attribute name="defaultselection" value="null" />

public var defaultselection;

The index of the default selected item, if none is provided via the selected="true" attribute on an item.
itemclassname: <attribute name="itemclassname" type="string" value="" />

public var itemclassname : String;

The name of the class for new items that will be created with addItem().
multiselect: <attribute name="multiselect" value="false" />

public var multiselect;

If multiselect is true, multiple items may be selected. When the shift key is down, a range of items is selected. When the control key is down, any item may be added to the selection.
toggleselected: <attribute name="toggleselected" value="false" />

public var toggleselected;

When true, the first click on a list item selects it and the second click deselects it.

Methods (17)

addItem(): <method name="addItem" args="text, value" />

public function addItem(text : String, value : Object);

Add an item to the end of the list. This method is not available with dataoption="lazy" or dataoption="resize" (use the data APIs instead).
clearSelection(): <method name="clearSelection" />

public function clearSelection();

Clear the current selection.
getItem(): <method name="getItem" args="value" />

public function getItem(value : Object) : Object;

Find a particular item by value. This method is not available with dataoption="lazy" or dataoption="resize" (use the data APIs instead).
getItemAt(): <method name="getItemAt" args="index" />

public function getItemAt(index : Number) : Object;

Get a particular item by its index. This method is not available with dataoption="lazy" or dataoption="resize" (use the data APIs instead).
getNumItems(): <method name="getNumItems" />

public function getNumItems() : Number;

Get the number of items in the list.
getSelection(): <method name="getSelection" />

public function getSelection() : Object;

Get the selection for the list. Normally this method returns views, but if dataoption="lazy" or dataoption="resize", it will return datapointers.
getText(): <method name="getText" />

public function getText() : Object;

Get text for the list.
getValue(): <method name="getValue" />

public function getValue() : Object;

Get the value(s) for the list.
moveSelection(): <method name="moveSelection" args="dir" />

public function moveSelection(dir : Number);

Move the selection to the next or previous view. This method not available with dataoption="lazy" or dataoption="resize"
removeItem(): <method name="removeItem" args="value" />

public function removeItem(value : Object);

Find the first item with the specified value and remove it from the list. This method is not available with dataoption="lazy" or dataoption="resize" (use the data APIs instead).
removeItemAt(): <method name="removeItemAt" args="index" />

public function removeItemAt(index : Number);

Find the item at the specified index and remove it from the list. This method is not available with dataoption="lazy" or dataoption="resize" (use data APIs instead).
select(): <method name="select" args="item" />

public function select(item : LzView);

Select an item.
selectItem(): <method name="selectItem" args="value" />

public function selectItem(value : Object);

Select an item by value. This method is not available with dataoption="lazy" or dataoption="resize".
selectItemAt(): <method name="selectItemAt" args="index" />

public function selectItemAt(index : Number);

Select an item by index.
selectNext(): <method name="selectNext" />

public function selectNext();

Move the selection to the next view. This method not available with dataoption="lazy" or dataoption="resize".
selectPrev(): <method name="selectPrev" />

public function selectPrev();

Move the selection to the previous view. This method not available with dataoption="lazy" or dataoption="resize".
setHilite(): <method name="setHilite" args="v" />

public function setHilite(v : LzView);

Set which view has the hilite.

Events (1)

onselect: <attribute name="onselect" />

public event onselect;

This event is triggered whenever the user makes a selection it may used as a script in the tag or as an event method.

LZX Synopsis

</class>

JavaScript Synopsis

public baselist extends baseformitem {

public var dataoption : String;

public var defaultselection ;

public var itemclassname : String;

public var multiselect ;

public var toggleselected ;

prototype public function addItem (text : String, value : Object);

prototype public function clearSelection ();

prototype public function getItem (value : Object) : Object;

prototype public function getItemAt (index : Number) : Object;

prototype public function getNumItems () : Number;

prototype public function getSelection () : Object;

prototype public function getText () : Object;

prototype public function getValue () : Object;

prototype public function moveSelection (dir : Number);

prototype public event onselect ;

prototype public function removeItem (value : Object);

prototype public function removeItemAt (index : Number);

prototype public function select (item : LzView);

prototype public function selectItem (value : Object);

prototype public function selectItemAt (index : Number);

prototype public function selectNext ();

prototype public function selectPrev ();

prototype public function setHilite (v : LzView);

}

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