Using
lists
You can use lists to present information to the user in simple lists
with scroll bars. You can present this information with text and pictures
(in a PictureListBox) or with text alone (using a ListBox).
Depending on how you design your application, the user can select
one or more list items to perform an action based on the list
selection.
You add ListBox and PictureListBox controls to windows in the same
way you add other controls: select ListBox or PictureListBox from the
Insert>Control menu and click the window.
Adding items to list
controls
In the painter
Use the Item property page for the control to add new items.
To add items to a ListBox or PictureListBox:
-
Select the Items tab in the Properties view for the
control. -
Enter the name of the items for the ListBox. For a
PictureListBox, also enter a picture index number to associate the
item with a picture.For instructions on adding pictures to a PictureListBox, see
Adding pictures to
PictureListBox controls.
In a script
Use the AddItem and InsertItem functions to dynamically add items to
a ListBox or PictureListBox at runtime. AddItem adds items to the end of
the list. However, if the list is sorted, the item will then be moved to
its position in the sort order. Use InsertItem if you want to specify
where in the list the item will be inserted.
|
Function |
You supply |
|---|---|
|
InsertItem |
Item name Position in which the item will Picture index (for a |
|
AddItem |
Item name Picture index (for a |
For example, this script adds items to a ListBox:
|
1 2 3 4 |
This.AddItem ("Vaporware") This.InsertItem ("Software",2) This.InsertItem ("Hardware",2) This.InsertItem ("Paperware",2) |
This script adds items and images to a PictureListBox:
|
1 2 3 4 |
This.AddItem ("Monitor",2) This.AddItem ("Modem", 3) This.AddItem ("Printer",4) This.InsertItem ("Scanner",5,1) |
Using the Sort property
You can set the control’s sort property to TRUE or check the
Sorted check box on the General property page to ensure that the items
in the list are always arranged in ascending alphabetical order.
Adding pictures to PictureListBox
controls
In the painter
Use the Pictures and Items property pages for the control to add
pictures.
To add pictures to a PictureListBox:
-
Select the Pictures tab in the Properties view for the
control. -
Select an image from the stock image list, or use the Browse
button to select a bitmap, cursor, or icon image. -
Select a color from the PictureMaskColor drop-down menu for the
image.The color selected for the picture mask will appear transparent
in the PictureListBox. -
Select a picture height and width.
This will control the size of the images in the
PictureListBox.Dynamically changing image size
You can use a script to change the image size at runtime by
setting the PictureHeight and PictureWidth properties before you add
any pictures when you create a PictureListBox.For more information about PictureHeight and PictureWidth, see
the section called “PictureHeight” in Objects and Controls
and the section called “PictureWidth” in Objects and Controls. -
Repeat the procedure for the number of images you plan to use in
your PictureListBox. -
Select the Items tab and change the Picture Index for each item
to the appropriate number.
In a script
Use the AddPicture function to dynamically add pictures to a
PictureListBox at runtime. For example, the script below sets the size of
the picture, adds a BMP file to the PictureListBox, and adds an item to
the control:
|
1 2 3 4 |
This.PictureHeight = 75 This.PictureWidth = 75 This.AddPicture ("c:ArtGalmpsutterfly.bmp") This.AddItem("Aine Minogue",8) |
Deleting pictures from picture list
controls
Use the DeletePicture and DeletePictures functions to delete
pictures from either a PictureListBox or a DropDownPictureListBox.
When you use the DeletePicture function, you must supply the picture
index of the picture you want to delete.
For example:
|
1 |
This.DeletePicture (1) |
deletes the first Picture from the control, and
|
1 |
This.DeletePictures () |
deletes all the pictures in a control.
Example
The following window contains a ListBox control and a
PictureListBox. The ListBox control contains four items, and the
PictureListBox has one:
When the user double-clicks an item in the ListBox, a script
executes to:
-
Delete all the items in the PictureListBox
-
Add new items to the PictureListBox that are related to the
ListBox item that was double-clicked
This is the script used in the ListBox DoubleClicked event:
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 |
int li_count //Find out the number of items //in the PictureListBox li_count = plb_1.totalItems() // Find out which item was double-clicked // Then: // * Delete all the items in the PictureListBox // * Add the items associated with the // double-clicked item CHOOSE CASE index CASE 1 DO WHILE plb_1.totalitems() > 0 plb_1.DeleteItem(plb_1.totalitems()) LOOP plb_1.AddItem("Monitor",2) plb_1.AddItem("Modem",3) plb_1.AddItem("Printer",4) plb_1.InsertItem("Scanner",5,1) CASE 2 DO WHILE plb_1.totalitems() > 0 plb_1.DeleteItem(plb_1.totalitems()) LOOP plb_1.InsertItem("GreenBar",6,1) plb_1.InsertItem("LetterHead",7,1) plb_1.InsertItem("Copy",8,1) plb_1.InsertItem("50 lb.",9,1) CASE 3 DO WHILE plb_1.totalitems() > 0 plb_1.DeleteItem(plb_1.totalitems()) LOOP plb_1.InsertItem("SpreadIt!",10,1) plb_1.InsertItem("WriteOn!",11,1) plb_1.InsertItem("WebMaker!",12,1) plb_1.InsertItem("Chessaholic",13,1) CASE 4 DO WHILE plb_1.totalitems() > 0 plb_1.DeleteItem(plb_1.totalitems()) LOOP plb_1.InsertItem("AlnaWarehouse",14,1) plb_1.InsertItem("AlnaInfo",15,1) plb_1.InsertItem("Info9000",16,1) plb_1.InsertItem("AlnaThink",17,1) END CHOOSE |