BBjWebComponent::setCallback

Description

In BBj 24.00 and higher, this method registers the callback routine for a specified BBjWebComponent event. These event type codes are defined by the individual web components.

Syntax

Return Value Method
void setCallback(String eventType, CustomObject customObject, String methodName)
void setCallback(String eventType, CustomObject customObject, String methodName, BBjWebEventOptions options)
void setCallback(String eventType, String subroutineName)
void setCallback(String eventType, String subroutineName, BBjWebEventOptions options)

Parameters

Parameter Description
eventType Event type for which the callback is to be registered.
subroutineName Subroutine name to be executed in PROCESS_EVENTS.
customObject A CustomObject containing the method to be called when the event is processed by PROCESS_EVENTS.
methodName

The name of the method that is to be called when the event is processed by PROCESS_EVENTS. The method must take a single BBjWebEvent parameter:

method public void onWebEvent(BBjWebEvent event!)
    rem ' handle a BBjWebEvent.
methodend
options An optional BBjWebEventOptions structure that specifies JavaScript code to execute inside the client-side event handler and a list of values to return from the event or component.

Return Value

None.

Remarks

Web Event callbacks can be registered for any string event code. Supported events are defined by the individual components. Internally, this maps to addEventListener.

The setCallback method will implicitly GOSUB to the subroutine specified in subroutineName. Since the block of code executed at subroutineName is arrived at via an implicit GOSUB, a RETURN is required at the end of the subroutine.

The setCallback method will implicitly CALL a program at the specified label when the subroutineName parameter includes "::" (e.g.: "EventHandlerProgram::label"). Since a CALL has been made to a public program, an ENTER may optionally be used at the beginning, and an EXIT is required at the end.

The setCallback method must be called before the PROCESS_EVENTS verb, or within a subroutine that is called in response to an event.

If the setCallback method specifies a non-null BBjWebEventOptions, multiple BBjWebComponent callbacks can be registered for a given eventType. If the setCallback method does not specify a BBjWebEventOptions parameter, or if the parameter is null, only the last one registered is used, as in BBjControl::setCallback.

Example

rem ' BBjWebComponent

sysgui = unt
open (sysgui)"X0"
title$ = "BBjWebComponent"
sysgui! = bbjapi().getSysGui()
flags$ = $00190083$; rem ' DWC flow layout
flags$ = $00090083$; rem ' absolute layout
window! = sysgui!.addWindow(25,25,300,750,title$,flags$)
window!.setCallback(window!.ON_CLOSE,"eoj")
browser! = bbjapi().getWebManager(err=oops)
browser!.setCallback(browser!.ON_SCRIPT_LOADED,"loaded",err=oops)
browser!.setCallback(browser!.ON_SCRIPT_FAILED,"failed",err=oops)
browser!.setCallback(browser!.ON_STYLE_LOADED,"loaded",err=oops)
browser!.setCallback(browser!.ON_STYLE_FAILED,"failed",err=oops)

url$ = "https://cdn.jsdelivr.net/npm/@microsoft/fast-components/dist/fast-components.min.js"
top = 1
attributes$ = "type=module"
browser!.injectScriptUrl(url$, top, attributes$)

url$ = "https://cdn.jsdelivr.net/npm/@shoelace-style/shoelace@latest/cdn/themes/light.css"
top = 1
attributes$ = ""
browser!.injectStyleUrl(url$, top, attributes$)

url$ = "https://cdn.jsdelivr.net/npm/@shoelace-style/shoelace@latest/cdn/themes/dark.css"
top = 1
attributes$ = ""
browser!.injectStyleUrl(url$, top, attributes$)

rem ' https://shoelace.style/getting-started/installation
url$ = "https://cdn.jsdelivr.net/npm/@shoelace-style/shoelace@latest/cdn/shoelace.js"
url$ = "https://cdn.jsdelivr.net/npm/@shoelace-style/shoelace@latest/cdn/shoelace-autoloader.js"
top = 1
attributes$ = "type=module"
browser!.injectScriptUrl(url$, top, attributes$)

tagName$ = "fast-button"
fast_button! = window!.addWebComponent(101,25,25,100,25,tagName$)
fast_button!.setText(tagName$)
fast_button!.setStyle("width","")
fast_button!.setStyle("height","")
tooltip$ = "https://www.fast.design/docs/components/button"
fast_button!.setAttribute("title",tooltip$)
fast_button!.setAttribute("appearance","accent")
fast_button!.setCallback(fast_button!.ON_DEFINED,"event")
fast_button!.setCallback(fast_button!.ON_MOUSE_ENTER,"event")
fast_button!.setCallback(fast_button!.ON_MOUSE_EXIT,"event")
fast_button!.setCallback(fast_button!.ON_GAINED_FOCUS,"event")
fast_button!.setCallback(fast_button!.ON_LOST_FOCUS,"event")
fast_button!.setCallback("click","event")

light! = window!.addRadioButton(102,125,25,75,25,"Light",$0020$)
light!.setCallback(light!.ON_CHECK_ON,"light")

dark! = window!.addRadioButton(103,200,25,75,25,"Dark",$0020$)
dark!.setCallback(dark!.ON_CHECK_ON,"dark")

theme! = window!.addRadioGroup()
theme!.add(light!)
theme!.add(dark!)

tagName$ = "sl-button"

sl_button! = window!.addWebComponent(104,25,75,250,25,tagName$)
sl_button!.setProperty("size","small")
sl_button!.setText(tagName$)
tooltip$ = "https://shoelace.style/components/button"
sl_button!.setAttribute("title",tooltip$)
sl_button!.setCallback(sl_button!.ON_DEFINED,"event")
sl_button!.setCallback(sl_button!.ON_MOUSE_ENTER,"event")
sl_button!.setCallback(sl_button!.ON_MOUSE_EXIT,"event")
sl_button!.setCallback(sl_button!.ON_GAINED_FOCUS,"event")
sl_button!.setCallback(sl_button!.ON_LOST_FOCUS,"event")
sl_button!.setCallback("click","event")

sl_button! = window!.addWebComponent(105,25,125,250,25,tagName$)
sl_button!.setAttribute("pill","")
sl_button!.setText(tagName$+" pill")
tooltip$ = "https://shoelace.style/components/button"
sl_button!.setAttribute("title",tooltip$)
sl_button!.setCallback(sl_button!.ON_DEFINED,"event")
sl_button!.setCallback(sl_button!.ON_MOUSE_ENTER,"event")
sl_button!.setCallback(sl_button!.ON_MOUSE_EXIT,"event")
sl_button!.setCallback(sl_button!.ON_GAINED_FOCUS,"event")
sl_button!.setCallback(sl_button!.ON_LOST_FOCUS,"event")

tagName$ = "sl-switch"

sl_switch! = window!.addWebComponent(106,25,175,150,25,tagName$)
sl_switch!.setProperty("size","large")
sl_switch!.setText(tagName$)
tooltip$ = "https://shoelace.style/components/switch"
sl_switch!.setAttribute("title",tooltip$)
sl_switch!.setCallback(sl_switch!.ON_DEFINED,"event")
sl_switch!.setCallback(sl_switch!.ON_EXECUTE_SCRIPT,"event")
sl_switch!.setCallback(sl_switch!.ON_MOUSE_ENTER,"event")
sl_switch!.setCallback(sl_switch!.ON_MOUSE_EXIT,"event")
sl_switch!.setCallback(sl_switch!.ON_GAINED_FOCUS,"event")
sl_switch!.setCallback(sl_switch!.ON_LOST_FOCUS,"event")
sl_switch!.setCallback("sl-change","webevent")
sl_switch!.clearCallback("sl-change")
options! = sl_switch!.newEventOptions()
options!.setCode("console.log('testing custom event code.')")
options!.setFilter("event.target.checked")
options!.addItem("checked","event.target.checked")
sl_switch!.setCallback("sl-change","webevent",options!)

button! = window!.addButton(107,200,175,75,25,"Click",$$)
button!.setCallback(button!.ON_BUTTON_PUSH,"click")

tagName$ = "sl-button-group"

sl_button_group! = window!.addWebComponent(108,25,225,200,25,tagName$,$$)
tooltip$ = "https://shoelace.style/components/button-group"
sl_button_group!.setAttribute("title",tooltip$)
sl_button_group!.setCallback(sl_button_group!.ON_DEFINED,"event")
rem sl_button_group!.setCallback(sl_button_group!.ON_MOUSE_ENTER,"event")
rem sl_button_group!.setCallback(sl_button_group!.ON_MOUSE_EXIT,"event")
rem sl_button_group!.setCallback(sl_button_group!.ON_GAINED_FOCUS,"event")
rem sl_button_group!.setCallback(sl_button_group!.ON_LOST_FOCUS,"event")
rem sl_button_group!.setCallback("click","event")

left! = window!.addWebComponent(201,0,0,0,0,"sl-button",$0010$)
left!.setAttribute("title","left")
left!.setCallback(left!.ON_DEFINED,"event")
left!.setCallback(left!.ON_MOUSE_ENTER,"event")
left!.setCallback(left!.ON_MOUSE_EXIT,"event")
left!.setCallback(left!.ON_GAINED_FOCUS,"event")
left!.setCallback(left!.ON_LOST_FOCUS,"event")
left!.setCallback("click","event")
left!.setText("Left")

center! = window!.addWebComponent(202,0,0,0,0,"sl-button",$0010$)
center!.setAttribute("title","center")
center!.setCallback(center!.ON_DEFINED,"event")
center!.setCallback(center!.ON_MOUSE_ENTER,"event")
center!.setCallback(center!.ON_MOUSE_EXIT,"event")
center!.setCallback(center!.ON_GAINED_FOCUS,"event")
center!.setCallback(center!.ON_LOST_FOCUS,"event")
center!.setCallback("click","event")
center!.setText("Center")

right! = window!.addWebComponent(203,0,0,0,0,"sl-button",$0010$)
right!.setAttribute("title","right")
right!.setCallback(right!.ON_DEFINED,"event")
right!.setCallback(right!.ON_MOUSE_ENTER,"event")
right!.setCallback(right!.ON_MOUSE_EXIT,"event")
right!.setCallback(right!.ON_GAINED_FOCUS,"event")
right!.setCallback(right!.ON_LOST_FOCUS,"event")
right!.setCallback("click","event")
right!.setText("Right")

sl_button_group!.setSlot(left!)
sl_button_group!.setSlot(center!)
sl_button_group!.setSlot(right!)

tagName$ = "input"
input! = window!.addWebComponent(109,235,225,40,30,tagName$,$$)
input!.setProperty("autocomplete","off")
input!.setAttribute("title","keydown")
options! = input!.newEventOptions()
options!.setCode("event.preventDefault()")
options!.addItem("key","event.key")
options!.addItem("code","event.code")
options!.addItem("location","event.location")
options!.addItem("ctrlKey","event.ctrlKey")
options!.addItem("shiftKey","event.shiftKey")
options!.addItem("altKey","event.altKey")
options!.addItem("metaKey","event.metaKey")
input!.setCallback("keydown","keydown",options!)

rem https://shoelace.style/components/color-picker

tagName$ = "sl-color-picker"

sl_color_picker! = window!.addWebComponent(204,25,275,40,25,tagName$)
sl_color_picker!.setProperty("size","large")
sl_color_picker!.setAttribute("title","https://shoelace.style/components/color-picker")
r = rnd(255), g = rnd(255), b = rnd(255)
value$ = "#" + hta(chr(r)) + hta(chr(g)) + hta(chr(b))
sl_color_picker!.setProperty("value",value$)

hex! = window!.addButton(205,100,275,50,35,"hex",$$)
hex!.setCallback(hex!.ON_BUTTON_PUSH,"color")

rgb! = window!.addButton(206,150,275,50,35,"rgb",$$)
rgb!.setCallback(rgb!.ON_BUTTON_PUSH,"color")

hsl! = window!.addButton(207,200,275,50,35,"hsl",$$)
hsl!.setCallback(hsl!.ON_BUTTON_PUSH,"color")

tagName$ = "sl-card"
sl_card! = window!.addWebComponent(300,25,310,250,25,tagName$,$$)
sl_card!.setText("This is a kitten, but not just any kitten. This kitten likes walking along pallets.")
tooltip$ = "https://shoelace.style/components/card"
sl_card!.setAttribute("title",tooltip$)
sl_card!.setCallback(sl_card!.ON_DEFINED,"event")
sl_card!.setCallback(sl_card!.ON_MOUSE_ENTER,"event")
sl_card!.setCallback(sl_card!.ON_MOUSE_EXIT,"event")
sl_card!.setCallback(sl_card!.ON_GAINED_FOCUS,"event")
sl_card!.setCallback(sl_card!.ON_LOST_FOCUS,"event")
sl_card!.setCallback("click","event")
sl_card!.setStyle("font","16px sans-serif")
sl_card!.setStyle("color","var(--sl-color-neutral-900)")
sl_card!.setStyle("padding","1rem")

sl_card_image! = window!.addWebComponent(301,0,0,0,0,"img")
sl_card_image!.setCallback(sl_card_image!.ON_DEFINED,"event")
sl_card_image!.setAttribute("src","https://images.unsplash.com/photo-1547191783-94d5f8f6d8b1?ixlib=rb-1.2.1&ixid=eyJhcHBfaWQiOjEyMDd9&auto=format&fit=crop&w=400&q=80")
sl_card_image!.setAttribute("alt","A kitten walks towards camera on top of pallet.")
sl_card_image!.setAttribute("slot","image")

sl_card_header! = window!.addWebComponent(302,0,0,0,0,"span")
sl_card_header!.setCallback(sl_card_header!.ON_DEFINED,"event")
sl_card_header!.setHtml("<h1>A cat</h1>")
sl_card_header!.setAttribute("slot","header")

sl_card_footer! = window!.addWebComponent(304,0,0,0,0,"span")
sl_card_footer!.setCallback(sl_card_footer!.ON_DEFINED,"event")
sl_card_footer!.setHtml("<small>Note: some people are more into dogs.</small>")
sl_card_footer!.setAttribute("slot","footer")

sl_card!.setSlot("image",sl_card_image!)
sl_card!.setSlot("header",sl_card_header!)
sl_card!.setSlot("footer",sl_card_footer!)

status! = window!.addStatusBar(99)

EventHandler! = new EventHandler()
EventHandler!.setStatusBar(status!)
sl_button!.setCallback("click",EventHandler!,"onWebEvent")

process_events

oops:
  i = msgbox("Not supported in this client.")
eoj:
  release

loaded:
  event! = sysgui!.getLastEvent()
  msg$ = date(0:"%Hz:%mz:%sz.%tz ")+event!.getEventName()+" url="+str(event!.getUrl())
  System.out.println(msg$)
return

failed:
  event! = sysgui!.getLastEvent()
  msg$ = date(0:"%Hz:%mz:%sz.%tz ")+event!.getEventName()+" url="+str(event!.getUrl())
  System.err.println(msg$)
  i = msgbox(msg$,16)
return

keydown:
rem event key = 3
rem event code = Digit3
rem event location = 0
rem event ctrlKey = false
rem event shiftKey = false
rem event altKey = false
rem event metaKey = false
  event! = sysgui!.getLastEvent()
  msg$ = date(0:"%Hz:%mz:%sz.%tz ")+event!.getEventName()
  msg$ = msg$ + " " + event!.getEventType()
  eventMap$ = ""
  map! = event!.getEventMap()
  iterator! = map!.keySet().iterator()
  while iterator!.hasNext()
    key$ = iterator!.next()
    value! = map!.get(key$)
    if value! = null() then value$ = "null" else value$ = String.valueOf(value!)
    eventMap$ = eventMap$ + " " + key$ + " = " + value$
  wend
  msg$ = msg$ + " " + eventMap$
  status!.setText(msg$)
  System.out.println(msg$)
return

event:
  event! = sysgui!.getLastEvent()
  msg$ = date(0:"%Hz:%mz:%sz.%tz ")+event!.getEventName()
  msg$ = msg$ + " " + event!.getEventType(err=*next)
  msg$ = msg$ + " custom=" + Boolean.toString(event!.isCustom(err=*next))
  msg$ = msg$ + " " + event!.getControl().getTagName(err=*next)
  msg$ = msg$ + " " + str(event!.getControl().getID())
  msg$ = msg$ + " " + event!.getControl().getText()
  status!.setText(msg$)
  System.out.println(msg$)
return

webevent:
  event! = sysgui!.getLastEvent()
  msg$ = date(0:"%Hz:%mz:%sz.%tz ")+event!.getEventName()
  msg$ = msg$ + " " + event!.getEventType()
  msg$ = msg$ + " "+ event!.getWebComponent().getTagName()
  msg$ = msg$ + " "+ event!.getControl().getText()
  status!.setText(msg$)
  System.out.println(msg$)
  eventMap$ = "getJsonString(): " + event!.getJsonString() + $0a0a$
  eventMap$ = ""
  map! = event!.getEventMap()
  iterator! = map!.keySet().iterator()
  while iterator!.hasNext()
    key$ = iterator!.next()
    value! = map!.get(key$)
    if value! = null() then value$ = "null" else value$ = String.valueOf(value!)
    eventMap$ = eventMap$ + key$ + " = " + value$ + $0a$
  wend
  i = msgbox(eventMap$,32768,event!.getEventName()+" "+event!.getEventType()+" getEventMap")
return

class public EventHandler
  field public BBjStatusBar StatusBar!
  method public void onWebEvent(BBjWebEvent event!)
    msg$ = date(0:"%Hz:%mz:%sz.%tz onWebEvent ")+event!.getEventName()
    msg$ = msg$ + " " + event!.getEventType()
    msg$ = msg$ + " "+ event!.getWebComponent().getTagName()
    msg$ = msg$ + " "+ event!.getControl().getText()
    #StatusBar!.setText(msg$)
    System.out.println(msg$)
  methodend
classend

click:
  sl_switch!.executeAsyncScript("component.click()")
return

rem ' https://shoelace.style/components/color-picker#methods

color:
  format$ = sysgui!.getLastEvent().getControl().getText()
  method$ = "getFormattedValue('"+format$+"')"
  color$ = sl_color_picker!.executeScript(method$)
  i = msgbox(color$,0,method$)
return

rem ' https://shoelace.style/getting-started/themes

light:
  browser!.removeClass("sl-theme-dark")
  browser!.addClass("sl-theme-light")
  browser!.setTheme("light")
  gosub classList
return

dark:
  browser!.removeClass("sl-theme-light")
  browser!.addClass("sl-theme-dark")
  browser!.setTheme("dark")
  gosub classList
return

classList:
  classList! = browser!.getClassList()
  classList$ = "getClassList: " + str(classList!)
  status!.setText(classList$)
return

ClosedVersion History

  • BBj 24.00: BBjWebComponent::setCallback added.

See Also

BBjAPI

Object Variables

BBjWebComponent::clearCallback

PROCESS EVENTS Verb

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