PowerBASIC Information Center Tutorials
These tutorials were written to help you get a quick, but thorough, understanding of PowerBASIC -
the scope of the language as well as it's specific capabilities.
StatusBar Control
The statusbar control provides a location for placing status information on a
dialog, typically along the bottom of the dialog. It may be split into parts to
show multiple data strings. It does not display images.
- Syntax:
Control Add StatusBar, hDlg, id&, txt$, x, y, xx, yy, _
style&, extsytle& CALL callback
- Source Code Example:
This short example creates a complete application with a single statusbar.
When clicked, the statusbar responds with a message.
This tutorial page discusses most of the statements used, however the
DDT,
Controls,
Messages, and
Callback tutorials provide
background information that may be helpful in understanding the example.
#Compile Exe
Global hDlg As Dword
Function PBMain() As Long
Dialog New Pixels, 0, "Statusbar Test",300,300,200,200, _
%WS_SysMenu, 0 To hDlg
Control Add Statusbar, hdlg, 500, "",0,0,0,0
Statusbar Set Parts hDlg, 500, 75,75,99999
Statusbar Set Text hdlg, 500, 1, 0, "one"
Statusbar Set Text hdlg, 500, 2, 0, "two"
Statusbar Set Text hdlg, 500, 3, 0, "three
Dialog Show Modal hDlg Call DlgProc
End Function
CallBack Function DlgProc() As Long
If Cb.NmCode = %NM_Click Then
MsgBox "click"
End If
End Function
An additional example of a callback function is provided further down this page.
- Visual Examples:
And here are a few examples of what you can do with the statusbar control in PowerBASIC.
Variations on the Control Add StatusBar statement were used to create the examples.
In some cases, other Control or StatusBar statements were used to modify the results.
The options are pretty basic. You can have one or more sections, each with its
own text. Sections can have their own border styel. You can also set the statusbar
at the bottom or top of the window.
Arguments
The Control Add statement is used to create all new controls. Here are the
statement's arguments and any special significance to the statusbar control.
- hDlg
The dialog handle to which the statusbar control is to be added. The value was returned
by the DIALOG NEW statement.
- id&
The id& argument is a control identifier assigned by the programmer.
It must be a value of 1-65535. Values of 100+ are suggested, as PowerBASIC
pre-assigns identifiers with special meaning. Numeric equates are
suggested over the use of literal values.
- txt$
When first created, a statusbar has only one part, whose text content is
provided by txt$.
Use of an ampersand in a statusbar section has no special meaning (i.e.,
the & does not define a hotkey as it does in some controls).
- x,y and xx,yy
The integer x,y and xx,yy dimensions use the same units as the parent dialog.
(x,y) is the upper/left coordinates of the control. (xx,yy) is the width/height
of the control.
Note: the definitions just given match those found in the Help file. However
the style& settings %css_top and %css_bottom override the x,y and xx,yy settings
and size the control with the width of the dialog and a height based on the current
font settings.
- style& and extstyle&
The style& and extstyle& arguments (listed below) are optional. If not supplied, default
values are used (see the table below). If values are supplied, they completely replace
default values (i.e., the entered values are not in addition to the default values).
- CALL
The "CALL callback" section is optional. If not supplied, the callback
function of the parent dialog is used. An example callback function for
statusbar controls is provided further down this page. The #MESSAGE COMMAND compiler
directive can be used to prevent sending %WS_NOTIFY messages to the callback
function. By default, both %WS_NOTIFY and %WS_COMMAND messages are sent.
StatusBar-Specific PowerBASIC Statements
The Control Add Statusbar statement simply adds a one-section toolbar.
To create multiple sections or to change the border, you must use the
following StatusBar Set statements. Up to 32 sections are allowed.
| StatusBar Set Parts
| creates sections, each with its own text
| | hDlg, id&, x$, y$, z$, ...
| |
| | StatusBar Set Text
| assigns text string for each part
| | hDlg, id&, item&, style&, text$
| |
|
The item& is the section number. Numbering goes left to right,
starting with 1.
The style options for the Statusbar Set Text statement are:
0 - border lower than dialog
%sbt_noborders - no borders (&H0100)
%sbt_popout - border higher than dialog (&H0200)
Use #INCLUDE on the file "CommCtrl.inc" to retreive the statusbar
equates.
If you put text into a statusbar and later increase the number of
sections, the existing text will be kept. If you decrease the number
of sections, the text in the dropped sections will be lost.
Here's an image of a 3-part statusbar and the source code used
to create it.
Control Add StatusBar, hdlg, 500, "status",0,0,0,0
StatusBar Set Parts hDlg, 500, 75,75,99999
StatusBar Set Text hdlg, 500, 1, 0, "one"
StatusBar Set Text hdlg, 500, 2, &H0100, "two"
StatusBar Set Text hdlg, 500, 3, &H0200, "three
Note the "99999" width of the 3rd section. Using an arbitrarily large
number insures that statusbar covers the entire width of the dialog.
Another approach is to resize the statusbar sections whenever the
dialog size changes - programmatically spreading the width of the
sections to meet application needs.
To use the %sbt_xxx equates in lieu of the literal values, include
the "CommCtrl.inc" file.
Messages, Notifications, Styles, and ExtSstyles
There are four types of named constants in the following table.
All are pulled from the
MSDN web site.
- Notifications - event notifications a control receives
- Messages - controls may send these
- Styles - affect the visual look of a control
- ExtStyles - additional values that affect the visual look
The first column contains control-specific named constants and the
second column contains generic window named constants (statusbar
controls are windows).
Also, if the PowerBASIC Help file has an entry on the value, it is
highlighted in yellow. If the value was noted in PowerBASIC Help as
a default value, it is also shown in bold text.
In the values for notifications, descriptions starting with -n and
-c refer to events received through the %wm_notify and %wm_command
messages. By default, PowerBASIC controls can receive both of these
messages.
And here is a short description of many of the named constants
corresponding to notifications, styles, and extstyle - particularly
those discussed in the PowerBASIC Help topics.
%ccs_bottom - place at bottom of dialog
%ccs_right - place at right edge of dialog
%nm_click -n mouse click
%nm_dblclk -n double click
%nm_rclick -n right mouse click
%nm_rdblclk -n right mouse double click
%sbars_sizegrip - sizegrip displayed
%sbars_tooltips - tooltips enabled
%sbn_simplemodechange -n simple mode has changed
%ws_ex_clientedge - apply sunken edge border
%ws_ex_staticedge - apply 3D border
%ws_ex_windowedge - apply raised edge border
Callback Function
A control can have its own callback function, or use the parent
dialog callback function.
A control callback function should return TRUE to indicate it
has processed the message. This prevents unnecessarily calling
the dialog callback function, which will process the message if
no control callback function is available, or if the control
callback function returns FALSE.
By default, both %WM_COMMAND and %WM_NOTIFY messages are received.
However, if the #MESSAGE COMMAND compiler directive is invoked,
the %WM_NOTIFY messages will not be available.
Here's a sample statusbar control callback function.
CallBack Function cbStatusBar()
Select Case CB.MSG
Case %WM_NOTIFY
Select Case CB.CTLMSG
Case %nm_click
Case %nm_dblclk
Case %nm_rclick
Case %nm_rdblclk
Case %nm_simplemodechange
End Select
End Select
End Function
In each Case section, add the statements the application needs to respond
to the event. Also, be sure to add "Function=1" as appropriate to indicate
that the event was handled by the callback function.
CONTROL Statement Syntax
The following table lists the various Control statements (except the ADD statements).
Most, but not all, can be used with the statusbar control. A one-line description of
the statement and then its syntax are presented.
| CONTROL DISABLE | disable
| | hDlg, id&
| |
| | CONTROL ENABLE | enable
| | hDlg, id&
| |
| | CONTROL GET CHECK | check state
| | hDlg, id& TO iResult1&
| |
| | CONTROL GET CLIENT | top/left location
| | hDlg, id& TO wide&, high&
| |
| | CONTROL GET LOC | top/left location
| | hDlg, id& TO x&, y&
| |
| | CONTROL GET SIZE | width/height
| | hDlg, id& TO width&, height&
| |
| | CONTROL GET TEXT | text
| | hDlg, id& TO txt$
| |
| | CONTROL GET USER | get user data
| | hDlg, id&, index& TO retvar&
| |
| | CONTROL HANDLE | window handle for control id
| | hDlg, id& TO hCtl&
| |
| | CONTROL KILL | remove control
| | hDlg, id&
| |
| | CONTROL POST | put message in queue (non-blocking)
| | hDlg, id&, Msg&, wParam&, lParam&
| |
| | CONTROL REDRAW | schedule redraw of control
| | hDlg, id&
| |
| | CONTROL SEND | send message to control, wait for processing
| | hDlg, id&, Msg&, wParam&, lParam& TO iResult2&
| |
| | CONTROL SET CHECK | set check for 3state or checkbox
| | hDlg, id&, checkstate&
| |
| | CONTROL SET CLIENT | change size to specific client area size
| | hDlg, id&, wide&, high&
| |
| | CONTROL SET COLOR | set fg/bg color
| | hDlg, id&, fgcolor&, bgcolor&
| |
| | CONTROL SET FOCUS | set focus
| | hDlg, id&
| |
| | CONTROL SET FONT | select font for a control
| | hDlg, id&, fonthandle&
| |
| | CONTROL SET LOC | relocate control within dialog
| | hDlg, id&, x&, y&
| |
| | CONTROL SET OPTION | set check state of option control
| | hDlg, id&, minid&, maxid&
| |
| | CONTROL SET SIZE | change control size
| | hDlg, id&, width&, height&
| |
| | CONTROL SET TEXT | change control text
| | hDlg, id&, text$
| |
| | CONTROL SET USER | set user data
| | hDlg, id&, index&, uservalue&
| |
| | CONTROL SHOW STATE | toggle visibility
| | hDlg, id&, showstate& TO iResult3&
| |
|
If you have any suggestions or corrections, please let me know.
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