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Q58673: ButtonOpen Incorrectly Handles Button in Resizable Window

Article: Q58673
Product(s): See article
Version(s): 7.00 7.10
Operating System(s): MS-DOS
Keyword(s): ENDUSER | SR# S900202-66 buglist7.00 buglist7.10 | mspl13_basic
Last Modified: 20-SEP-1990

The ButtonOpen SUBprogram in the User Interface (UI) Toolbox (in
WINDOW.BAS) incorrectly handles buttons in resizable windows and
buttons with invalid states. When trying to create a button with an
invalid state (such as state 3 for window type 2), the following
message displays and the program stops:

   Cannot open button on window that can be re-sized.

When you attempt to place a button in a resizable window, the above
message is not displayed, but no button is created. In this case, the
ButtonOpen SUB falls through without doing anything.

This information applies to Microsoft BASIC Professional Development
System (PDS) versions 7.00 and 7.10 for MS-DOS. The necessary
corrections to the WINDOW.BAS source code are listed below.

For additional corrections to source code in the User Interface
Toolbox, search in this Knowledge Base for the following words:

   User and Interface and Toolbox and buglist7.00

The section of code that must be modified is at the end of the
ButtonOpen SUB from WINDOW.BAS (Note: The underscores are used for
display purposes only):

  IF (resize AND buttonType >= 6) OR NOT resize THEN
...*** not all code displayed
    IF (buttonType = 1 AND state >= 1 AND state <= 3)_
    OR (buttonType >= 2 AND buttonType <= 3 AND state >= 1 AND state <= 2)_
    OR (buttonType >= 4 AND buttonType <= 7) THEN
...*** not all code displayed
    ELSE
        PRINT "Cannot open button on window that can be re-sized!"
        END
    END IF
  END IF
END SUB

The problem with the existing code is that the ELSE clause matches the
wrong level of the IF nesting. To modify the code to display correct
messages, change the above code to the following:

  IF (resize AND buttonType >= 6) OR NOT resize THEN
  ...*** not all code displayed
    IF (buttonType = 1 AND state >= 1 AND state <= 3)_
    OR (buttonType >= 2 AND buttonType <= 3 AND state >= 1 AND state <= 2)_
    OR (buttonType >= 4 AND buttonType <= 7) THEN
    ...*** not all code displayed

'The following lines have changed.
    ELSE
      PRINT "Illegal state ("; state; ") or button type ("; buttonType; ")"
      END
    END IF
  ELSE
    PRINT "Cannot open button on window that can be re-sized!"
    END
  END IF
END SUB

The following code examples demonstrate the two problems with the
unmodified ButtonOpen SUB:

Example 1
---------

This first example attempts to open a button, type 2 (check box), with
an invalid state, 3. This program displays the following incorrect
message using the unmodified code shipped with BASIC PDS 7.00 or 7.10:

   Cannot open button on window that can be re-sized.

After making the specified modifications to WINDOW.BAS, Example 1
displays the following correct message:

   Illegal state ( 3 ) or button type ( 2 )

REM $INCLUDE: 'General.bi'
REM $INCLUDE: 'Mouse.bi'
REM $INCLUDE: 'Menu.bi'
REM $INCLUDE: 'Window.bi'
COMMON SHARED /uitools/ GloMenu           AS MenuMiscType
COMMON SHARED /uitools/ GloTitle()        AS MenuTitleType
COMMON SHARED /uitools/ GloItem()         AS MenuItemType
COMMON SHARED /uitools/ GloWindow()       AS windowType
COMMON SHARED /uitools/ GloButton()       AS buttonType
COMMON SHARED /uitools/ GloEdit()         AS EditFieldType
COMMON SHARED /uitools/ GloStorage        AS WindowStorageType
COMMON SHARED /uitools/ GloWindowStack()  AS INTEGER
COMMON SHARED /uitools/ GloBuffer$()
'$DYNAMIC
DIM GloWindow(MAXWINDOW) AS windowType
DIM GloWindowStack(MAXWINDOW) AS INTEGER
DIM GloButton(MAXBUTTON) AS buttonType
DIM GloEdit(MAXBUTTON) AS EditFieldType
DIM GloBuffer$(MAXWINDOW + 1, 2)
CLS
WindowInit
Resize% = 0               'Not resizable
WindowOpen 1, 3, 3, 24, 24, 7, 0, 7, 0, 7, 7, 7, Resize%, 0, 1, "test"
buttonType% = 2              'Check box (valid states=1 and 2)
state% = 3                   '3 is invalid state for check box
CALL ButtonOpen(1, state%, "Foo", 10, 10, 20, 20, buttonType%)

Example 2
---------

The following example attempts to open a button in a resizable window.
This program executes without messages using the unmodified code
shipped with BASIC PDS 7.00 or 7.10, but no button is created.

After making the specified modifications to WINDOW.BAS, Example 2
displays the following correct message:

   Cannot open button on window that can be re-sized.

REM $INCLUDE: 'General.bi'
REM $INCLUDE: 'Mouse.bi'
REM $INCLUDE: 'Menu.bi'
REM $INCLUDE: 'Window.bi'
COMMON SHARED /uitools/ GloMenu           AS MenuMiscType
COMMON SHARED /uitools/ GloTitle()        AS MenuTitleType
COMMON SHARED /uitools/ GloItem()         AS MenuItemType
COMMON SHARED /uitools/ GloWindow()       AS windowType
COMMON SHARED /uitools/ GloButton()       AS buttonType
COMMON SHARED /uitools/ GloEdit()         AS EditFieldType
COMMON SHARED /uitools/ GloStorage        AS WindowStorageType
COMMON SHARED /uitools/ GloWindowStack()  AS INTEGER
COMMON SHARED /uitools/ GloBuffer$()
'$DYNAMIC
DIM GloWindow(MAXWINDOW) AS windowType
DIM GloWindowStack(MAXWINDOW) AS INTEGER
DIM GloButton(MAXBUTTON) AS buttonType
DIM GloEdit(MAXBUTTON) AS EditFieldType
DIM GloBuffer$(MAXWINDOW + 1, 2)
CLS
WindowInit
Resize% = TRUE                 'Resizable
WindowOpen 1, 3, 3, 24, 24, 7, 0, 7, 0, 7, 7, 7, Resize%, 0, 1, "test"
buttonType% = 2
state% = 1                     'Valid state.
CALL ButtonOpen(1, state%, "Foo", 10, 10, 20, 20, buttonType%)

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