PureBasic Forums - English

Posted: **Sun Aug 07, 2016 8:09 am**

I have taken Lebostein's example, stripped off all specific Linux and Windows code for a clearer outline (so now it's only runnable on MacOS) and implemented a second callback for the method tableViewSelectionDidChange: to catch and signal all selection changes in both of the two ListIconGadgets.

I have tested the example successfully on MacOS 10.6.8 (Snow Leopard) and MacOS 10.11.6 (El Capitan) with PB 5.43 x86 and x64 (ASCII and Unicode mode) and with PB 5.50 x86 and x64.

Code: Select all

EnableExplicit

ImportC ""
  sel_registerName(MethodName.P-ASCII)
  class_addMethod(Class.I, Selector.I, Implementation.I, Types.P-ASCII)
EndImport

Structure CallbackEntry
  WindowID.I
  ListIconID.I
  DefaultCallback.I
EndStructure

Define AppDelegate.I = CocoaMessage(0,
  CocoaMessage(0, 0, "NSApplication sharedApplication"), "delegate")
Define DelegateClass.I = CocoaMessage(0, AppDelegate, "class")
Define NotificationCenter.I = CocoaMessage(0, 0,
  "NSNotificationCenter defaultCenter")

NewList CallbackEntry.CallbackEntry()

ProcedureC ColumnHeaderClickCallback(Object.I, Selector.I, TableView.I,
  TableColumn.I)
  Shared CallbackEntry()
  
  Protected ClickedHeaderColumn.I
  
  ForEach CallbackEntry()
    If TableView = GadgetID(CallbackEntry()\ListIconID)
      Break
    EndIf
  Next
  
  ClickedHeaderColumn = Val(PeekS(CocoaMessage(0,
    CocoaMessage(0, TableColumn, "identifier"),
    "UTF8String"), -1, #PB_UTF8))
  PostEvent(#PB_Event_Gadget, CallbackEntry()\WindowID,
    CallbackEntry()\ListIconID, #PB_EventType_LeftClick,
    ClickedHeaderColumn + 1)
EndProcedure

ProcedureC SelectionDidChangeCallback(Object.I, Selector.I, Notification.I)
  Shared CallbackEntry()
  Static ChangeSignalled.I

  If ChangeSignalled
    PostEvent(#PB_Event_Gadget, CallbackEntry()\WindowID,
      CallbackEntry()\ListIconID, #PB_EventType_Change)
    ChangeSignalled = #False
  Else
    ChangeSignalled = #True
  EndIf
EndProcedure

Procedure SetGadgetCallback(WindowID.I, ListIconID.I)
  Shared AppDelegate.I
  Shared CallbackEntry()
  Shared DelegateClass.I
  Shared NotificationCenter.I
  
  AddElement(CallbackEntry())
  CallbackEntry()\WindowID = WindowID
  CallbackEntry()\ListIconID = ListIconID

  ; ----- Initialize callback for changing selection

  class_addMethod(DelegateClass,
    sel_registerName("tableViewSelectionDidChange:"),
    @SelectionDidChangeCallback(), "v@:@")
  CocoaMessage(0, NotificationCenter,
    "addObserver:", AppDelegate,
    "selector:", sel_registerName("tableViewSelectionDidChange:"),
    "name:$", @"NSTableViewSelectionDidChangeNotification",
    "object:", GadgetID(CallbackEntry()\ListIconID))

  ; ----- Initialize callback for header click

  class_addMethod(DelegateClass,
    sel_registerName("tableView:didClickTableColumn:"),
    @ColumnHeaderClickCallback(), "v@:@@")

  CocoaMessage(0, GadgetID(CallbackEntry()\ListIconID),
    "setDelegate:", AppDelegate)
EndProcedure

; ========================================== SPECIFIC CODE FOR TESTING

Enumeration
  #zero
  #windows_nb
  #list1_nb
  #list2_nb
EndEnumeration

#Title_column1$ = "Name"
#Title_column2$ = "Address"

Define GadgetID.I

OpenWindow(#windows_nb, 0, 0, 870, 110, "Detect left click on header cell",
  #PB_Window_SystemMenu | #PB_Window_ScreenCentered)

ListIconGadget(#list1_nb, 10, 10, 420, WindowHeight(#windows_nb) - 20,
  #Title_column1$, 110, #PB_ListIcon_FullRowSelect)
AddGadgetColumn(#list1_nb, 1, #Title_column2$, 300)
AddGadgetItem(#list1_nb, -1, "Harry Rannit" + #LF$ +
  "12 Parliament Way, Battle Street, By the Bay")
AddGadgetItem(#list1_nb, -1, "Ginger Brokeit"+ #LF$ +
  "130 PureBasic Road, BigTown, CodeCity")
AddGadgetItem(#list1_nb, -1, "Didi Foundit"+ #LF$ +
  "321 Logo Drive, Mouse House, Downtown")

ListIconGadget(#list2_nb, 440, 10, 420, WindowHeight(#windows_nb) - 20,
  #Title_column1$, 110, #PB_ListIcon_FullRowSelect)
AddGadgetColumn(#list2_nb, 1, #Title_column2$, 300)
AddGadgetItem(#list2_nb, -1, "Harry Rannit" + #LF$ +
  "12 Parliament Way, Battle Street, By the Bay")
AddGadgetItem(#list2_nb, -1, "Ginger Brokeit"+ #LF$ +
  "130 PureBasic Road, BigTown, CodeCity")
AddGadgetItem(#list2_nb, -1, "Didi Foundit"+ #LF$ +
  "321 Logo Drive, Mouse House, Downtown")

SetGadgetCallback(#windows_nb, #list1_nb)
SetGadgetCallback(#windows_nb, #list2_nb)

Repeat
  Select WaitWindowEvent()
    Case #PB_Event_CloseWindow
      Break
    Case #PB_Event_Gadget
      GadgetID = EventGadget()

      Select GadgetID
        Case #list1_nb, #list2_nb
          Select EventType()
          Case #PB_EventType_LeftClick
            If EventData()
              Debug "Left click on header of column " + Str(EventData() - 1) +
                ", Gadget " + Str(GadgetID)
            Else
              Debug "-> Left click on row " + Str(GetGadgetState(GadgetID)) +
                ", Gadget " + Str(GadgetID)
            EndIf
          Case #PB_EventType_Change
            Debug "Selected row changed:"
          EndSelect
      EndSelect
  EndSelect
ForEver

CocoaMessage(0, NotificationCenter, "removeObserver:", AppDelegate)

Posted: **Tue Sep 13, 2016 12:55 pm**

Thanks!!!! That's it!

Posted: **Tue Sep 13, 2016 2:17 pm**

I hope Fred will add the header click event to PB one day. In my eyes an essential thing for list table gadgets...

Posted: **Mon Jan 13, 2020 10:57 pm**

But #PB_EventType_Change returns the wrong GadgetID !!!!

add the gadget ID to the output:

Code: Select all

Debug "Selected row changed, Gadget " + Str(GadgetID)

Start the code and click on the entries on left and right. The GadgetID is everytime = 3, whether you click left or right.
But if you click one time the header, then it suddenly works....

Posted: **Tue Jan 14, 2020 9:15 pm**

Lebostein wrote:But #PB_EventType_Change returns the wrong GadgetID !!!!

add the gadget ID to the output:
Code: Select all
Debug "Selected row changed, Gadget " + Str(GadgetID)
Start the code and click on the entries on left and right. The GadgetID is everytime = 3, whether you click left or right.
But if you click one time the header, then it suddenly works....

You are right, it's a bug. The callback SelectionDidChangeCallback() is a notification callback which doesn't receive in its parameters the currently selected ListIconGadget (TableView) and column object (Table Column) like the ColumnHeaderClickCallback(). So in SelectionDidChangeCallback() PostEvent() incorrectly sends the previously selected linked list elements WindowID and ListIconID.

To eleminate this bug please change in SelectionDidChangeCallback() this code

Code: Select all

    PostEvent(#PB_Event_Gadget, CallbackEntry()\WindowID,
      CallbackEntry()\ListIconID, #PB_EventType_Change)

against this modified one

Code: Select all

    PostEvent(#PB_Event_Gadget, GetActiveWindow(), GetActiveGadget(),
      #PB_EventType_Change)

I have tested the modified example successfully on MacOS 10.14.6 'Mojave' with PB 5.71 x64.

Posted: **Wed Jan 15, 2020 11:17 am**

Thats it!!

Thanks a million!

Posted: **Fri Jan 17, 2020 2:23 pm**

Edit: It seems the last change influences other gadgets with the #PB_EventType_Change event. What about that solution? It seems it works, but I don't know if it's right:

Code: Select all

ProcedureC SelectionDidChangeCallback(Object.I, Selector.I, Notification.I)
  Shared CallbackEntry()
  Static ChangeSignalled.I

  ForEach CallbackEntry()
    If GetActiveWindow() = CallbackEntry()\WindowID And GetActiveGadget() = CallbackEntry()\ListIconID
      If ChangeSignalled
        PostEvent(#PB_Event_Gadget, CallbackEntry()\WindowID, CallbackEntry()\ListIconID, #PB_EventType_Change)
        ChangeSignalled = #False
      Else
        ChangeSignalled = #True
      EndIf
    EndIf
  Next

EndProcedure

Posted: **Sun Jan 19, 2020 10:35 am**

Lebostein wrote:Edit: It seems the last change influences other gadgets with the #PB_EventType_Change event. What about that solution? It seems it works, but I don't know if it's right:

Your solution should be even better than my proposition. Your solution takes care that the correct entry in the shared LinkedList CallbackEntry() is selected. Due to the sharing of the LinkedList CallbackEntry() in the callbacks, the change of an entry in a callback is also in effect in the main program.

PureBasic Forums - English

ListIconGadget: No #PB_EventType_Change!

Re: ListIconGadget: No #PB_EventType_Change!

Re: ListIconGadget: No #PB_EventType_Change!

Re: ListIconGadget: No #PB_EventType_Change!

Re: ListIconGadget: No #PB_EventType_Change!

Re: ListIconGadget: No #PB_EventType_Change!

Re: ListIconGadget: No #PB_EventType_Change!

Re: ListIconGadget: No #PB_EventType_Change!

Re: ListIconGadget: No #PB_EventType_Change!