How to access ImageList from TreeView and ListView control with Visual FoxPro code

Summary

This article illustrates how images of an ImageList control can be accessed by TreeView and ListView controls programmatically.

More Information

This section has two code examples. The first example illustrates how
ImageList images can be assigned to a TreeView control. In this example if Leaves are added to a Node of the TreeView, then a Closed Folder icon is assigned to the Node. If a node containing leaves is expanded, its icon changes to an Open Folder, and upon collapse, it changes back to the Closed Folder.


The second example shows how ImageList images can be assigned to a ListViewcontrol. In this example, when a List Item is created it is assigned a large icon. The item icons can then be toggled between a small and a large icon. For each type of icon--large and small--separate ImageList controls are used; otherwise, both types of icons appear as same size.


Note The folders containing the icon and bitmap files have changed in Visual FoxPro 6.0. The new location for the icons is:

home(4)+"icons\office\<filename>"
The new location for the bitmaps is:


home(4)+"bitmaps\outline\<Filename>"
Following is the sample code for the first example to assign ImageListimages to a TreeView:
   LVForm=CREATEOBJECT("MyLVForm")
LVForm.SHOW
READ EVENT

*** Define the Form to hold and display all the controls ***
DEFINE CLASS MyLVForm AS FORM
LEFT=23
HEIGHT=250
WIDTH=425
mndx=0
*** Add the Control Objects to the Form ***
ADD OBJECT ImageList1 AS MyImageList
ADD OBJECT TreeView1 AS MyTreeView
ADD OBJECT AddNode AS ANCButton
ADD OBJECT AddLeaf AS ALCButton
ADD OBJECT mDelete AS DCButton
ADD OBJECT mExit AS ECButton
ENDDEFINE

*** Define ImageList to Hold Images for the TreeView Control ***
DEFINE CLASS MyImageList AS OLECONTROL
OLECLASS="COMCTL.ImageListCtrl.1"
TOP=36
LEFT=420
PROCEDURE INIT
THIS.OBJECT.ListImages.ADD(1,,LOADPICTURE(home()+;
"samples\graphics\bmps\outline\closed.bmp"))
THIS.OBJECT.ListImages.ADD(2,,LOADPICTURE(home()+;
"samples\graphics\bmps\outline\open.bmp"))
ENDPROC
ENDDEFINE

*** Define the TreeView Control ***
DEFINE CLASS MyTreeView AS OLECONTROL
OLECLASS="COMCTL.TreeCtrl.1"
TOP=24
HEIGHT=169
WIDTH=300
LEFT=20
.OBJECT.LineStyle=1
VISIBLE=.T.

*** Set ImageList property to ImageList1 Images ***
PROCEDURE INIT
THIS.OBJECT.ImageList=THISFORM.ImageList1.OBJECT
ENDPROC
PROCEDURE nodeclick
LPARAMETERS NODE
ENDPROC

*** Assign Image for Collapsed object ***
PROCEDURE collapse
LPARAMETERS NODE
IF !EMPTY(NODE.IMAGE)
NODE.IMAGE=1
ENDIF
ENDPROC

*** Assign Image for Expanded object ***
PROCEDURE expand
LPARAMETERS NODE
IF !EMPTY(NODE.IMAGE)
NODE.IMAGE=2
ENDIF
ENDPROC
ENDDEFINE
*** Define the Add Node Command Button ***
DEFINE CLASS ANCButton AS COMMANDBUTTON
TOP=70
LEFT=350
HEIGHT=18
WIDTH=59
CAPTION="Add Node"
VISIBLE=.T.
PROCEDURE CLICK
mndxtxt=""
mndxtxt=ALLTRIM(STR(THISFORM.mndx))

THISFORM.TreeView1.nodes.ADD(,2,mndxtxt+;
"_",REPLICATE(mndxtxt,5),,0)
THISFORM.mndx=THISFORM.mndx+1
THISFORM.TreeView1.ENABLED=.T.
THISFORM.AddLeaf.ENABLED=.T.
THISFORM.mDelete.ENABLED=.T.
ENDPROC
ENDDEFINE
*** Define the Add Leaf Command Button ***
DEFINE CLASS ALCButton AS COMMANDBUTTON
TOP=100
LEFT=350
HEIGHT=18
WIDTH=59
CAPTION="Add Leaf"
VISIBLE=.T.
ENABLED=.F.
PROCEDURE CLICK
so=THISFORM.TreeView1.SELECTEDITEM
IF !ISNULL(so)
THISFORM.TreeView1.nodes.ADD(so.INDEX,;
4,,"Sub"+ALLTRIM(so.TEXT),,0)
so.IMAGE=1
ENDIF
THISFORM.REFRESH
ENDPROC
ENDDEFINE
*** Define the Delete Command Button ***
DEFINE CLASS DCButton AS COMMANDBUTTON
TOP=150
LEFT=350
HEIGHT=18
WIDTH=59
CAPTION="Delete"
VISIBLE=.T.
ENABLED=.F.
PROCEDURE CLICK
o=THISFORM.TreeView1.SELECTEDITEM
IF !ISNULL(o)
IF !ISNULL(o.PARENT)
IF o.PARENT.children<2
o.PARENT.IMAGE=0
ENDIF
ENDIF
THISFORM.TreeView1.nodes.REMOVE(o.INDEX)
ENDIF
ENDPROC
ENDDEFINE
*** Define the Exit Command Button ***
DEFINE CLASS ECButton AS COMMANDBUTTON
TOP=215
LEFT=180
WIDTH=70
HEIGHT=25
CAPTION="Exit"
VISIBLE=.T.
PROCEDURE CLICK
THISFORM.RELEASE
CLEAR EVENTS
ENDPROC
ENDDEFINE

Following is the sample code for the Second example:

LVForm=CREATEOBJECT("MYLVForm")
LVForm.SHOW
READ EVENT

*** Define the Form that will hold and display the controls ***
DEFINE CLASS MyLVForm AS FORM
LEFT=23
HEIGHT=300
WIDTH=478
lvitm=0
lvitxt=''
ADD OBJECT ImageList2 AS MyImageList1
ADD OBJECT ImageList3 AS MyImageList2
ADD OBJECT ListView1 AS MyListView
ADD OBJECT ADDITEM AS AICButton
ADD OBJECT LSIOption AS LSIOGroup
ADD OBJECT mDelete AS DButton
ADD OBJECT MExit AS ExButton
ENDDEFINE

*** Need separate ImageList Controls for Large and Small Icons of
*** ListView otherwise both type of icons will appear as same size
***
*** Define ImageList to Hold Large Icon Image for the ListView
*** Control

DEFINE CLASS MyImageList1 AS OLECONTROL
OLECLASS="COMCTL.ImageListCtrl.1"
TOP=204
LEFT=420
PROCEDURE INIT
THIS.OBJECT.ListImages.ADD(1,,LOADPICTURE(home(4)+;
"icons\office\folder01.ico"))
ENDPROC
ENDDEFINE

*** Define ImageList to Hold Small Icon Image for the
*** ListView Control

DEFINE CLASS MyImageList2 AS OLECONTROL
OLECLASS="COMCTL.ImageListCtrl.1"
TOP=264
LEFT=420
PROCEDURE INIT
THIS.OBJECT.ListImages.ADD(1,,LOADPICTURE(home(4)+;
"bitmaps\outline\closed.bmp"))
ENDPROC
ENDDEFINE

*** Define the ListView Class ***
DEFINE CLASS MyListView AS OLECONTROL
OLECLASS="COMCTL.ListViewCtrl.1"
TOP=24
HEIGHT=169
WIDTH=275
LEFT=36
.OBJECT.LineStyle=1
VISIBLE=.T.

*** Set the ListView Icons property to Images in ImageList1 ***
*** and SmallIcons property to Images in ImageList2 ***

PROCEDURE INIT
THIS.OBJECT.icons=THISFORM.ImageList2.OBJECT
THIS.OBJECT.smallicons=THISFORM.ImageList3.OBJECT
ENDPROC
ENDDEFINE

*** Define the Add Item Button Class ***
DEFINE CLASS AICButton AS COMMANDBUTTON
TOP=50
LEFT=360
HEIGHT=18
WIDTH=59
CAPTION="Add Item"
VISIBLE=.T.
PROCEDURE CLICK
THISFORM.lvitm=THISFORM.lvitm+1
THISFORM.lvitxt=ALLTRIM(STR(THISFORM.lvitm))
x=THISFORM.ListView1.OBJECT.listitems.ADD;
(,THISFORM.lvitxt+"_","Item"+THISFORM.lvitxt,)
x.smallicon=1
x.ICON=1
THISFORM.LSIOption.ENABLED=.T.
THISFORM.mDelete.ENABLED=.T.
THISFORM.REFRESH
ENDPROC
ENDDEFINE

*** Define the Large/Small Icon Option Group ***
DEFINE CLASS LSIOGroup AS OPTIONGROUP
BUTTONCOUNT = 2
VALUE = 1
HEIGHT = 39
LEFT = 340
TOP = 80
WIDTH = 96
Option1.CAPTION = "Large Icon"
Option1.LEFT = 11
Option1.TOP = 5
Option1.WIDTH = 82
Option1.NAME = "Option1"
Option2.CAPTION = "Small Icon"
Option2.LEFT = 11
Option2.TOP = 20
Option2.WIDTH = 82
Option2.NAME = "Option2"
PROCEDURE INTERACTIVECHANGE
DO CASE
CASE THIS.VALUE=1
THISFORM.ListView1.OBJECT.VIEW=0
CASE THIS.VALUE=2
THISFORM.ListView1.OBJECT.VIEW=1
ENDCASE
THISFORM.REFRESH
ENDPROC
ENDDEFINE
*** Define the Delete Button Class ***
DEFINE CLASS DButton AS COMMANDBUTTON
TOP=156
LEFT=360
HEIGHT=18
WIDTH=59
CAPTION="Delete"
VISIBLE=.T.
ENABLED=.F.
PROCEDURE CLICK
o=THISFORM.ListView1.SELECTEDITEM
IF !ISNULL(o)
THISFORM.ListView1.listitems.REMOVE(o.INDEX)
ENDIF
ENDPROC
ENDDEFINE

*** Define the Exit Button Class
DEFINE CLASS ExButton AS COMMANDBUTTON
TOP=226
LEFT=192
WIDTH=192
HEIGHT=18
WIDTH=59
CAPTION="Exit"
VISIBLE=.T.
PROCEDURE CLICK
THISFORM.RELEASE
CLEAR EVENTS
ENDPROC
ENDDEFINE

References

For additional information, click the following article numbers to view the articles in the Microsoft Knowledge Base:

166937 Programmatically adding images to ImageList control

160921 Error using OLE controls

163803 Cannot set ImageList property of Treeview visually

Proprietà

ID articolo: 170146 - Ultima revisione: 20 giu 2008 - Revisione: 1

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