TreeView
You can use TreeView controls in your application to represent
relationships among hierarchical data. An example of a TreeView
implementation is PowerBuilder’s Browser. The tab pages in the Browser
contain TreeView controls.
Adding TreeView items and
pictures
A TreeView consists of TreeView items that are associated with
one or more pictures. You add images to a TreeView in the same way
that you add images to a PictureListBox.
For more information, see Adding images
to a PictureListBox.
Dynamically changing image size
The image size can be changed at runtime by setting the
PictureHeight and PictureWidth properties when you create a
TreeView.
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.
To add items to a TreeView
-
Write a script in the TreeView constructor event to create
TreeView items.
For more information about populating a TreeView, see the section called “Populating
TreeViews” in Application Techniques
and the section called “TreeView control” in Objects and Controls.
Adding state pictures to TreeView
items
A state picture is an image that appears to the left of the
TreeView item indicating that the item is not in its normal mode. A
state picture could indicate that a TreeView item is being changed, or
that it is performing a process and is unavailable for action.
To specify a state picture for a TreeView item
-
Select the TreeView control to display its properties in the
Properties view and then select the State tab. -
Do one of the following:
-
Use the StatePictureName drop-down list to select stock
pictures to add to the TreeView. -
Use the Browse button to select any bitmap (BMP), icon
(ICO), GIF, JPEG or PNG file.
-
To specify a cursor file
To use a cursor file, you must type the file name. You cannot
select it.
Working in the Properties view with the rows in the State or
Pictures tab page is the same as working with them in a ListView
control. For information, see ListView.
To activate a state picture for a TreeView item
-
Write a script that changes the image when
appropriate.For example, the following script gets the current TreeView
item and displays the state picture for it.1234567long ll_tvitreeviewitem tvill_tvi = tv_foo.finditem(currenttreeitem!, 0)tv_foo.getitem(ll_tvi, tvi)tvi.statepictureindex = 1tv_foo.setitem(ll_tvi, tvi)
For more information on the TreeView control, see Using
TreeView Controls in Application Techniques.
Setting other properties
To specify other TreeView properties
-
Select the TreeView control to display its properties in the
Properties view and then select the General tab. -
Enter a name for the TreeView in the Name text box and
specify other properties as appropriate. Among the properties you
can specify on the General property page are:-
The border style
-
Whether the TreeView has lines showing the item
hierarchy -
Whether the TreeView includes collapse and expand
buttons -
Whether the user can delete items
-
Whether the user can drag and drop items into the
TreeView
-
For more information, right-click in any tab page in the
Properties view and select Help from the pop-up menu.
For other options, choose the tab appropriate to the property
you want to specify:
|
To specify |
Choose this tab |
|---|---|
|
The images used to represent TreeView |
Pictures |
|
The state images for the TreeView |
State |
|
The font size, family, and color for TreeView |
Font |
|
The size and position of the |
Other |
|
The icon for the mouse pointer in the |
Other |
|
The icon for a drag item, and whether the |
Other |
For more information on the TreeView control, see Using
TreeView Controls in Application Techniques. For information about its
properties, see the section called “TreeView control” in Objects and Controls.