BBjListButton

Description

The BBjListButton object provides methods for manipulating a GUI list button control.

Implemented Interfaces

DropTarget, Editable, Focusable, MouseWheelEnabled, RecordSetBindable,RecordSetFillable,SimpleRecordSetBindable,TabTraversable, TextAlignable,Validateable

Creation

BBjAPI > BBjSysGui > BBjWindow > BBjListButton

A BBjListButton object is created through the following BBjWindow methods:

Methods of BBjListButton

Methods of BBjListButton implemented for DropTarget

Methods of BBjListButton implemented for Editable

Methods of BBjListButton implemented for Focusable

Methods of BBjListButton implemented for MouseWheelEnabled

Methods of BBjListButton implemented for RecordSetBindable

Methods of BBjListButton implemented for RecordSetFillable

Methods of BBjListButton implemented for SimpleRecordSetBindable

Methods of BBjListButton implemented for TabTraversable

Methods of BBjListButton implemented for TextAlignable

Methods of BBjListButton implemented for Validateable

Methods of BBjListButton inherited from BBjControl

Events

CSS

The visual appearance of BUI controls is defined using CSS (cascading style sheets) rules. Easily change the default colors, border, and other settings by customizing these rules, all without changing any application code. See CSS API for a high-level overview of BUI CSS.

In BBj 13 and higher, the default BUI BBjListButton is implemented as a custom control, to allow for CSS styling that isn't possible with native browser select elements. The native browser select elements can provide a better user experience on mobile phone and tablet browsers; the NATIVE_BROWSER_LIST !OPTIONS setting can be set to TRUE to specify that style.

The native version of the BUI BBjListButton is implemented as a <select> element with the .BBjListButton.bbj-native style name.

In BBj 10 and higher, native style BUI BBjListButton controls don't honor the deselect() method. Applications that depend on this method should set the LISTBUTTON_DESELECT method. Applications that depend on this method should set the LISTBUTTON_DESELECT setting to TRUE. This option has no effect in GUI.

By default, BBj immediately populates BUI list controls (BBjListBox, BBjListButton, BBjListEdit) with all items sent by the program. With very large lists containing many hundreds or thousands of items, this can take a bit of time. In BBj 13 and higher, the list controls can be configured to preload a smaller number of items. For example:

listpagesize$ = stbl("!LIST_PAGE_SIZE","16")

This example tells the BUI list controls to preload only 16 elements, then add more as the user scrolls. If this STBL isn't defined, or if it's set to "0", the BUI list controls preload the entire list.

!LIST_PAGE_SIZE doesn't apply to GUI, and it doesn't apply to the NATIVE_BROWSER_LIST versions of the BUI list controls.

The custom listbutton defines the following style names:

.BBjListButton (the top level control)

.BBjListButton-button (the button face)

.BBjListButton-buttonText (the left side of the button, which contains the text label)

.BBjListButton-imageWrapper (the right side of the button, which contains the dropdown arrow)

.BBjListButton-image (the dropdown arrow image)

.BBjListButton-listPanel (the dropdown container for the list)

.BBjListButton-listBox (the dropdown list)

.BBjListButton-item(an individual item in the dropdown list)

.BBjListButton-item.bbj-selected(the selected item)

.BBjListButton.bbj-disabled(the control is disabled)

.BBjListButton.bbj-focused(the control is focused)

.BBjListButton.bbj-readonly(the control is read only)

This section uses the list sample from the BBj BUI Showcase (code, demo).

With the default styles, the custom BBjListButton looks like this:

With the styles shown below, it looks like this:

Remarks

In BBj 5 and higher, typing into a BBjListButton control accumulates keystrokes entered within a specified number of milliseconds into a typeahead buffer. This allows the user, for example, to jump directly to New York in a list of all 50 states by quickly typing "NY". Without this typeahead buffer, the user would have to press "N" eight times to skip past the other state codes beginning with "N." The default time window for this feature is 1000 milliseconds (1 second). The !LISTSEARCH global overrides that timeout value; a setting of zero effectively disables this buffer.

In BBj 13.00 and higher, the LISTBUTTON_AUTO_SELECT !OPTIONS setting can be set to TRUE to select the Visual PRO/5 default behavior of auto-selecting index 0 when items are added to a previously empty list. The default behavior in BBj is to not auto-select index 0.

In BBj 13.01 and higher, the LISTBUTTON_SELECT !OPTIONS setting can be set to TRUE to auto-select index 0 when creating a non-empty BBjListButton. The default behavior is to not auto-select index 0 on creation.

Constants inherited from BBjControl

Example

rem 'Add a list button control to a window

rem 'Obtain the instance of the BBjAPI object
let myAPI! = BBjAPI()

rem 'Open the SysGui device
SYSGUI = UNT
OPEN (SYSGUI) "X0"

rem 'Obtain the instance of the BBjSysGui object
let mySysGui! = myAPI!.getSysGui()

rem 'Set addWindow param values
X = 10
Y = 10
WIDTH = 200
HEIGHT = 200
TITLE$="BBj Window"

rem 'Set the current context
mySysGui!.setContext(0)

rem 'Create a window
myWindow! = mySysGui!.addWindow(X,Y,WIDTH,HEIGHT,TITLE$)

rem 'Add a list button control to the window
myListButton! = myWindow!.addListButton(101,50,100,90,60,"",$0000$)

rem 'Add items into the list button
FOR I = 1 TO 4
    ITEM$="ITEM " + STR(I)
    myListButton!.addItem(ITEM$)
NEXT I

rem 'Register the CALLBACK routines
CALLBACK(ON_LIST_SELECT,LIST_ITEM_SELECTED,mySysGui!.getContext(),myListButton!.getID())
CALLBACK(ON_CLOSE,APP_CLOSE,mySysGui!.getContext())

rem 'Process Events
process_events

rem 'Callback routine called when the user selects an item in the list button
LIST_ITEM_SELECTED:
    rem 'Display a message with the select list button item
    MESSAGE$="The item selected is: " + STR(myListButton!.getItemAt(myListButton!.getSelectedIndex()))
    let X = MSGBOX(MESSAGE$)
return

rem 'Callback routine called when the user closes the application window
APP_CLOSE:
release

See Also

BBjAPI

BBjSysGui

BBjWindow

LISTBUTTON Mnemonic - Create a List Button Control

CALLBACK Verb - Register BBj Subroutine

DWC Component: dwc-choicebox

See the BBj Object Diagram for an illustration of the relationship between BBj Objects.