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Article: Q162249
Product(s): Microsoft FoxPro
Version(s): 
Operating System(s): 
Keyword(s): kbcode kbOOP kbvfp500 kbvfp600
Last Modified: 13-AUG-1999

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, versions 5.0, 6.0 
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SUMMARY
=======

A ToolBar is a class that is meant to be used with a variety of different forms.
Because of this, a ToolBar's ComboBox, which shows a list of items relevant to
the data shown on a particular form, generally will not be populated until the
ToolBar that contains it is bound to that form.

This article presents approaches to placing a ComboBox in a ToolBar, and several
different methods of populating a ComboBox.

Two of the ComboBoxes in Example 2 do not work, but they are intentionally
included to demonstrate that an object that is instantiated before the object
that contains it cannot be defined as having data from its container as its
RowSource. A ComboBox in a ToolBar is instantiated before the ToolBar, which is
instantiated before the formset (which ultimately contains the ToolBar) is
instantiated. The data shown in the ComboBox must be defined from within the
methods of the ComboBox, or placed there by events that happen after the
ComboBox is instantiated.

MORE INFORMATION
================

Here are two different examples. The first defines the objects visually, and the
second defines them within a program.

Example 1
---------

This example shows you how to create a ToolBar with 3 ComboBoxes through the user
interface by using the class designer and the form designer. Two of the
ComboBoxes are populated within methods of the containing ToolBar. The third is
populated from the Init event of the formset that uses the ToolBar.

In Visual FoxPro, create the ToolBar as follows:

1. On the File menu, click New. Select Class, and choose New File.

2. The New Class dialog box appears. Enter the following:

     Class Name:  tbrTest
     Based On:    Toolbar
     Store In:    Test.VCX

  Click OK.

3. The Class Designer appears on the Visual FoxPro desktop. Be sure the Forms
  Control ToolBar is visible. If not, select Forms Control Toolbar from the
  View menu so that particular option has a checkmark at the left.

  Add a three ComboBox controls to the ToolBar. Leave the default control names
  so that tbrTest contains controls named Combo1, Combo2, and Combo3.

4. On the Class menu, select New Property. Enter "aArray2(10,1)" (without the
  quotes) as the Name. Click Add, and then click Close.

5. If the Properties window is not visible, go to the View menu and click
  Properties.

  Select tbrTest in the Object list at the top. Double-click "Init Event" in the
  list of properties. The Edit window for the Init Event of tbrTest appears.
  Enter the following code:

     ** ToolBar tbrTest Init event
     ** aArray2 is dimensioned as a new property of the
     ** tbrTest ToolBar class.
     THIS.aArray2(1) = "Newspapers"
     THIS.aArray2(2) = "Magazines"
     THIS.aArray2(3) = "Radio"
     THIS.aArray2(4) = "Television"
     THIS.aArray2(5) = "Cable"
     THIS.aArray2(6) = "Direct Mail"
     THIS.aArray2(7) = "the Internet"
     THIS.aArray2(8) = "Billboards"
     THIS.aArray2(9) = "Telemarketing"
     THIS.aArray2(10) = "Word-of-mouth"

     ** The next 3 lines populate Combo2 using the AddItem method.
     i = 0
     FOR i = 1 to ALEN(THIS.aArray2)
     THIS.Combo2.AddItem(This.aArray2(i))
     NEXT

     ** The next 3 lines populate Combo3 using the properties
     ** of that ComboBox.
     THIS.Combo3.RowSourcetype = 5    && Type Array
     THIS.Combo3.RowSource = "THIS.Parent.aArray2"

     ** The code uses the string at the right in the line above
     ** in the Requery method of the Combo as the RowSource
     ** for the Combo.
     THIS.Combo3.Requery
     ******** End of tbrTest Init Event ********

6. On the File menu, click Close and then click Yes to save the file.

7. On the File menu, click New. Click Form and select New File.

8. On the Forms Control ToolBar, click View Classes (usually the #2 control on
  the Forms Control ToolBar). Click Add, and then select the class library you
  specified in step 2.

9. An abbreviated controls ToolBar appears. The tbrTest ToolBar appears as three
  tiny command buttons arrayed in a horizontal row. (If there are several
  similar controls, the tooltip will identify tbrTest.) Select tbrTest and
  place it by clicking on the form. Click Yes to create a form set object.

10. In the Properties window, select the Formset1 object in the ComboBox at the
  top.

11. Select New Property from the Form menu. Enter "aArray1(10,1)" (without the
  quotes) as the name. Click Add, then click Close.

12. In the Properties window for the Formset, set the Name property to "frsTest"
  (without the quotes).

13. In the Properties window, double-click the Init Event line. When the edit
  window for frsTest.Init appears, enter the following code:

      *** Init event code for formset frsTest ***
      IF TYPE("THIS.form1") = "O" && Ensures the form is instantiated.
        THIS.tbrTest.left = THIS.form1.left
        THIS.tbrTest.top = THIS.form1.top - (THIS.tbrTest.height + 25)
      ENDIF
      THIS.aArray1(1) = "This is 1"
      THIS.aArray1(2) = "This is 2"
      THIS.aArray1(3) = "This is 3"
      THIS.aArray1(4) = "This is 4"
      THIS.aArray1(5) = "This is 5"
      THIS.tbrTest.Combo1.AddItem(THIS.aArray1(5))
      THIS.tbrTest.Combo1.AddItem(THIS.aArray1(4))
      THIS.tbrTest.Combo1.AddItem(THIS.aArray1(3))
      THIS.tbrTest.Combo1.AddItem(THIS.aArray1(2))
      THIS.tbrTest.Combo1.AddItem(THIS.aArray1(1))
      *** End if frsTest Init event code ***

14. Press Ctrl+W to save the code in the edit window. On the File menu, click
  Save As. Specify frsTest as the name of the .scx file.

  Run the form by clicking the red exclamation point tool on the Visual FoxPro
  main ToolBar. You should see an empty form, with the tbrTest ToolBar
  immediately above that form. Each Combo should show the list of information
  the above code provided.

Example 2
---------

This example shows you how to create a ToolBar programmatically, and then use it
on a formset that is created programmatically. Enter the following code into a
new program named tbrTest:

     *************************************************
     ** tbrTest.prg
     **   Sample program to populate ComboBoxes in
     **   a ToolBar.
     *************************************************

     DIMENSION aFifthArray(10,1)
     aFifthArray(1) = "Boston"
     aFifthArray(2) = "Providence"
     aFifthArray(3) = "New Haven"
     aFifthArray(4) = "Armonk"
     aFifthArray(5) = "Grand Central"

     Dimension aSixthArray(10,1)
     aSixthArray(1) = "James"
     aSixthArray(2) = "Charles"
     aSixthArray(3) = "Hudson"
     aSixthArray(4) = "Rapahoneck"
     aSixthArray(5) = "Catawba"
     aSixthArray(6) = "Susquehanna"
     aSixthArray(7) = "Cooper"
     aSixthArray(8) = "Pee Dee"
     aSixthArray(9) = "Neuss"
     aSixthArray(10) = "Ohio"

     MyFormset = CREATEOBJECT("FormSet")
     WITH MyFormset
        .AddObject("tbrTools1", "tbrTest")
        .AddObject("Myform", "form1")
        WITH .myform
           .AddObject("quitter", "cmdClose")
           WITH .Quitter
             .top = 150
             .left = 200
             .visible = .T.
           ENDWITH
           .top = 100
           .left = 10
           .visible = .T.
        ENDWITH
        WITH .tbrTools1
           .top = myformset.myform.top - 60
           .Left = myformset.myform.left
           .visible = .T.
           WITH .Combo5
              .AddItem(aFifthArray(1))
              .AddItem(aFifthArray(2))
              .AddItem(aFifthArray(3))
              .AddItem(aFifthArray(4))
              .AddItem(aFifthArray(5))
           ENDWITH
           WITH .Combo6
              .RowSourcetype = 5
              .RowSource = "aSixthArray"
              .Requery
           ENDWITH
        ENDWITH
     ENDWITH

     READ EVENTS

     DEFINE CLASS form1 AS FORM
        Height = 100
        Width = 500
        Top = 100
        Left = 10
        ADD OBJECT cmdQuit as cmdClose
     ENDDEFINE

     DEFINE CLASS cmdClose AS CommandButton
        Height = 29
        Width = 50
        Caption = "\<Close"

        PROCEDURE Click
          ThisFormSet.Release
          CLEAR EVENTS
       ENDPROC
     ENDDEFINE

     DEFINE CLASS tbrTest AS TOOLBAR
        ADD OBJECT Combo1 AS COMBOBOX
        ADD OBJECT Combo2 AS COMBOBOX
        ADD OBJECT Combo3 AS COMBOBOX
        ADD OBJECT Combo4 AS COMBOBOX
        ADD OBJECT Combo5 AS COMBOBOX
        ADD OBJECT Combo6 AS COMBOBOX

     * Start of the class defInition: one ToolBar with 6 ComboBoxes.

        Left = 1
        Top  = 1
        Width = 575
        Caption = "Test ToolBar #2"
        Combo1.Height = 27
        Combo1.Width = 82
        Combo2.Height = 27
        Combo2.Width = 82
        Combo3.Height = 27
        Combo3.Width = 82
        Combo4.Height = 27
        Combo4.Width = 82
        Combo5.Height = 27
        Combo5.Width = 82
        Combo6.Height = 27
        Combo6.Width = 82

     PROCEDURE Load
     * ComboBox2 does not exist at Load time.
        Dimension gaArray1(10,1)
        gaArray1(1) = "Arkansas"
        gaArray1(2) = "Colorado"
        gaArray1(3) = "Delaware"
        gaArray1(4) = "Georgia"
        THIS.Combo2.AddItem(This.gaArray1(1))
        THIS.Combo2.AddItem(This.gaArray1(2))
        THIS.Combo2.AddItem(This.gaArray1(3))
        THIS.Combo2.AddItem(This.gaArray1(4))
     ENDPROC

     * Sets properties of the controls.
     * Notice that there are no Top or Left property settings for
     * controls on a ToolBar. Controls on a ToolBar are automatically
     * positioned in the order they are added.

     PROCEDURE Activate
     * ComboBox1 is populated within the activate procedure of the ToolBar.
        THIS.Combo1.AddItem("This is item 1")
        THIS.Combo1.AddItem("This is item 2")
        THIS.Combo1.AddItem("This is item 3")
        THIS.Combo1.AddItem("There are no more")

     * ComboBox2 is populated from array elements declared
     * and populated in the Load event of the ToolBar, but this code is
     * run before the ToolBar is loaded, so it causes the error "Property
     * 'GARALPHARRAY' is not found."
     *THIS.Combo2.AddItem(This.gaArray1(1))
     *THIS.Combo2.AddItem(This.gaArray1(2))
     *THIS.Combo2.AddItem(This.gaArray1(3))
     *THIS.Combo2.AddItem(This.gaArray1(4))

     * The following code depends upon the formset having a
     * gaSomeArray() defined and populated, but it suffers from the same
     * problem as the code immediately above, and causes the error
     * "Property 'GASOMEARRAY' is not found."
     *THIS.Combo3.AddItem(THISFORMSET.gaSomeArray(1))
     *THIS.Combo3.AddItem(THISFORMSET.gaSomeArray(2))
     *THIS.Combo3.AddItem(THISFORMSET.gaSomeArray(3))
     *THIS.Combo3.AddItem(THISFORMSET.gaSomeArray(4))

     DIMENSION gaArray4(10,1)
     gaArray4(1) = "Seattle"
     gaArray4(2) = "Portland"
     gaArray4(3) = "San Francisco"
     gaArray4(4) = "Los Angeles"
     gaArray4(5) = "San Diego"

     THIS.Combo4.AddItem(gaArray4(1))
     THIS.Combo4.AddItem(gaArray4(2))
     THIS.Combo4.AddItem(gaArray4(3))
     THIS.Combo4.AddItem(gaArray4(4))
     THIS.Combo4.AddItem(gaArray4(5))

     * ComboBox5 is populated from program code run after the
     * formset is loaded, Initialized, and populated, from an
     * array declared and Initialized before the formset is
     * created.

     ENDDEFINE    && End of ToolBar class defInition

(c) Microsoft Corporation 1997, All Rights Reserved. Contributions by Chris
Jensen, Microsoft Corporation


Additional query words:

======================================================================
Keywords          : kbcode kbOOP kbvfp500 kbvfp600 
Technology        : kbVFPsearch kbAudDeveloper kbVFP500 kbVFP600
Issue type        : kbhowto

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Q162249: HOWTO: Create a Toolbar Containing a ComboBox
