Dec 232017
 
Dialog box routines for use by Object Professional owners. Source included, but TP5.5 and OPRO 1.01+ required.
File ULDIAL.ZIP from The Programmer’s Corner in
Category Pascal Source Code
Dialog box routines for use by Object Professional owners. Source included, but TP5.5 and OPRO 1.01+ required.
File Name File Size Zip Size Zip Type
TESTDIAL.EXE 124448 48461 deflated
TESTDIAL.PAS 2994 1211 deflated
ULDEFINE.INC 1333 426 deflated
ULDIAL.DOC 18965 5853 deflated
ULDIAL.PAS 19989 4640 deflated
ULROOT.PAS 15983 4560 deflated

Download File ULDIAL.ZIP Here

Contents of the ULDIAL.DOC file



Dialog Objects as Enhancements to Turbo Power OOP Professional
New Communications Technology, Inc.
Version 2.0
by John Poindexter
CIS 73717,3405
July 12, 1990

Ok Cancel



Version 2.0 of this unit makes some major improvements in encapsulating the
details of the radio buttons and providing more flexibility in the
instantiation of dialog boxes.

The main object of this unit is DialogBox, an object to display short messages
or instructions, get user input if desired and exit using radio buttons. There
is also a timeout provision so the box can be used for temporary messages that
are to be displayed for a short period of time and then clear. The above logo
is a simulation of what you will get. The new object RadioButtons is self
contained and may be used in situations other than DialogBox.

Object hierarchy:

[Root] [Root] [Root]
DialogBox [AbstractWindow] [StringArray]
[RawWindow] MStringArray
[StackWindow]
[CommandWindow]
[AbstractSelector]
EntryScreen
[PickList]
RadioButtons

DialogBox although an immediate descendant of Root contains an EntryScreenPtr
field and RadioButtonsPtr fields and uses MStringArray which adds a data field
and method that keep track of the maximum string length of added strings.

DialogBox has an automatic sizing feature which is the reason for making it an
immediate descendant of Root rather than EntryScreen.

The minimal statements to use DialogBox look like this:

if not MyDialog.Init(rbHoriz,1,30,2,20) then Exit;
with MyDialog do
begin
AddMessageString('This is a test of DialogBox.');
AddChoiceString('Ok Cancel');
AddHeader(' My Test ', heTC);
Process;
Code := GetLastChoice;
Done;
end;

Unit ULDial uses Unit ULRoot which is included in the archive. TESTDIAL.EXE is
an interactive testing program that will give you an opportunity to try out
DialogBox.

Types.
======
HorizVerticalType = (rbHoriz, rbVertical);

Constants.
==========
ucULDial = 201
Unit code for Unit ULDial.

scOk = 0
scCancel = 1
scRetry = 2
scTimeOut = 99
Status codes which may be used for exit status of DialogBox.

Variables.
==========
ULRootColorSet : ColorSet
This is initialized to ULColorSet which is in ULRoot.

ButtonFrame : FrameArray
This is initialized to SglWindowFrame in ULDial.

Miscellaneous error codes and error messages are in ULRoot.

Objects.
========
MStringArrayPtr = ^MStringArray
MStringArray = object(StringArray)
msMaxLen : byte;
...
function AddMString(St : string): word;
function GetMaxLen: byte;
end;

RadioButtonsPtr = ^RadioButtons
RadioButtons = object(PickList)
rbChoices : MStringArrayPtr;
rbOrient : HorizVerticalType;
...
constructor Init();
destructor Done; virtual;
procedure ItemString(); virtual;
procedure ProcessSelf; virtual;
end;

DialogBoxPtr = ^DialogBox;
DialogBox = object(Root)
dlText : MStringArrayPtr;
dlChoices : MStringArrayPtr;
dlEntry : EntryScreenPtr;
dlButtons : RadioButtonsPtr;
...
constructor Init();
constructor InitDeluxe();

destructor Done; virtual;
procedure Clear;
function GetLastError: word;
procedure Process; virtual;
procedure AddMessageString(Msg: string);
procedure AddChoiceString(Choice: string);
procedure AddChoice(Choice: string);
procedure AddHeader(S: string; Posn: HeaderPosType);
procedure AddStringEntryField();
function CreateBox: boolean; virtual;
function GetLastChoice: word;
function GetEditedString: string;
procedure SetTimeOut(Delay: word);
end;

RadioButtons Methods.
=====================

Declaration
constructor Init(X1,Y1,X2,Y2: byte; var Colors: ColorSet;
Options: longint; Orientation: HorizVerticalType;
NrRows, NrCols: byte; CharExit: boolean;
CommandHandler: pkGenlProc;
PickOptions: word; Choices: MStringArrayPtr);
Purpose
Initialize this descendant of PickList which when drawn will display an
arrangement of radio buttons.
Description
X1,Y1,X2,Y2 define the four corners of the active PickList window. They
should be calculated based on the width of the choices, the orientation, the
number of rows and number of columns of radio buttons. See DialogBox's
CreateBox method for and example of calculating these window coordinates.
Colors and Options are the normal parameters for windows. Orientation refers
to the arrangement of radio buttons. Note this is a different type parameter
from the one used in PickLists. The difference between rbHoriz and
rbVertical is in whether the radio buttons scroll horizontally or vertically
if there are more buttons than can be shown in the active window.
NrRows and NrCols refers to the number of rows and columns of radio buttons
and not to the number of character positions covered by the buttons. A
button looks like this:
Cancel

The type of frame around the button may be changed by assigning a new value
to ButtonFrame.

The first character of the choice inside the button will be highlighted.
CharExit defines whether the PickList search method used is PickCharSearch
(CharExit = false) or PickCharExit (CharExit = true) as defined in OPRO
manual page 4-199. CommandHandler and PickOptions are the same as you would
use for a PickList. Choices is the string array that contains the labels
that are placed in the radio buttons.

Init assumes you will be using the standard CommandHandler, PickCommands,
and makes some adjustments to it depending on the orientation. Since radio
buttons are normally used in a dialog box that may have an entry field,
there needs to be a way of moving from the entry field to the buttons and
vice versa. For the horizontal arrangement cursor up is assigned to the exit
command ccUser0. For the vertical arrangement cursor left is assigned to
ccUser0.

Declaration
destructor Done; virtual
Purpose
To dispose of the RadioButtons object and restore PickCommands to the
standard assignments.
Description
It does not dispose of the Choices array.

Declaration
procedure ItemString(Item: word; Mode: pkMode; var IType: pkItemType;
var IString: string); virtual;
Purpose
This is a PickList ItemString method for returning the strings to be
displayed in the PickList.
Description
In the case of RadioButtons this method is specially tailored to produce the
radio button icons with the labels contained in the Choice array. The top
and bottom rows of each button are separate items in the PickList display
and are give the the pkProtected attribute. The area of highlighting for the
selected choice is limited to exclude the frame charcters by using Flex
attributes.

Declaration
procedure ProcessSelf; virtual
Purpose
To provide a seamless interface between the RadioButtons window field in an
entry screen and other fields in the entry screen.
Description
This method overrides the standard PickList ProcessSelf. ccSelect and
ccMouseSel are changed to ccDone so that the selection of a radio button
choice will exit the entry screen Process. ccUser0 is changed to BackTab to
move back to earlier entry screen fields.

DialogBox Methods.
==================

Declaration
constructor Init(Orientation: HorizVerticalType;
NumTextLines, TotalTextChars,
NumChoices, TotalChoiceChars: word);
Purpose
Initialize internal data fields and allocate MStringArrays for storing
lines of message text and choices.
Description
Orientation is either rbHoriz or rbVertical as explained above.
NumTextLines is the maximum number of lines of text that you will want
displayed as a message in the DialogBox.
TotalTextChars = NumTextLines * AveLengthOfEachLine
NumChoices is the number of radio buttons that you want. Each radio button
displays one word from the ChoiceString.
TotalChoiceChars = NumChoices * (AveLenghtOfEachChoice + 4)
Since DialogBox uses a descendant of StringArrays for storing the lines of
message Text to be displayed and the Choices, it is good practice to
allocate your best estimate of the memory storage requirements through Init.
However the StringArrays can reallocate if there is enough memory.
Reallocation will fragment memory.

For the EntryScreen field of DialogBox, Init uses the default
ULRootColorSet, the default window options DefWindowOptions+wBordered,
NrRows and NrCols equal 1, and CharExit equals false. Init will center the
dialog box on the screen, truncating and limiting the number of rows of
message lines to make everything fit in the screen space available.

Declaration
constructor InitDeluxe(X1, Y1: word; Options: longint;
Colors: ColorSet;
Orientation: HorizVerticalType;
NrRows, NrCols: byte; CharExit: boolean;
NumTextLines, TotalTextChars,
NumChoices, TotalChoiceChars: word);
Purpose
To provide more flexibility that the default based Init in instantiating a
DialogBox.
Description
X1 and Y1 define the upper left corner of the EntryScreen that is created by
CreateBox. The actual position is adjusted so that the DialogBox will fit on
the screen. The visible DialogBox is actually an EntryScreen. Values of 0,0
will cause the box to be centered on the screen. Values of ScreenWidth and
ScreenHeight will always place the DialogBox in the lower right corner of
the screen. Options define the window options used by the entry screen.
Orientation is as explained above. NrRows, NrCols and CharExit are as
explained under RadioButtons. The last 4 parameters are the same as for
Init.

Declaration
destructor Done; virtual;
Purpose
Deallocate all memory associated with DialogBox.
Description
This includes memory for EntryScreen, RadioButtons, Text and Choice Arrays.

Declaration
procedure Clear;
Purpose
To set up the DialogBox for a new message and set of Choices.
Description
This resets the Message and Choice arrays by disposing of them and then
reallocating at the same size. The EntryScreen is also disposed and all
DialogBox data fields reinitialized. It is useful in those situations where
you want to keep a DialogBox initialized and just keep sending new messages
and choices. Using this technique limits heap fragmentation.

Declaration
function GetLastError: word;
Purpose
To return the last error recorded by DialogBox.
Description
Returns the error code and resets dlLastError to 0.

Declaration
procedure Process;
Purpose
To activate the DialogBox in preparation for obtaining user input.
Description
Process is a little different from other process methods in OPRO. It calls
the method CreateBox described below to create the radio buttons
(dlButtons^) and the EntryScreen (dlEntry^); add the text fields, the string
entry field (if there is one) and the window field (dlButtons^). It then calls
dlEntry^.Process and waits for an exit selection. Process uses the standard
OPRO EntryCommands and PickCommands sets. If UseMouse is defined, as it is
in ULDEFINE.INC, and a mouse is installed, the mouse is enabled. After an
exit selection has been made Process also erases the DialogBox. If
SetTimeOut has been used to set a delay time before the box is automatically
erased, Process first calls Draw.

Declaration
procedure AddMessageString(Msg: string);
Purpose
To add message strings which will be displayed as TextFields in the entry
screen to be created.
Description
You can add as many message strings as you want, but keep in mind that only
those that will display on a full screen will be displayed and the lines
will be truncated to fit in a full screen window with a border. The entry
screen window is sized automatically as described under CreateBox. The
maximum number of text lines that can be displayed is
(ScreenHeight-5-NumberOfStringFieldLines). You do not have to add a message
string if you just want the radio buttons. If you stay within the memory
allocation specified in Init, then this is not likely to fail. Otherwise you
should check GetLastError after adding. In the rbHoriz mode the message
strings are centered. If you don't want them centered, just pad your strings
with blanks.

Declaration
procedure AddChoice(Choice: string);
Purpose
To add exit choices that will be displayed in the radio button icons.
Description
Each Choice string is displayed as a label in a radio button icon. It is an
error (epFatal+ecNoChoice) not to add a Choice string and the string may not
be blank. If you stay within the memory allocation requirements specified in
Init, this is not likely to fail. Otherwise you should check GetLastError
after adding.
Example
AddChoice('Sometimes');
AddChoice('Always');
AddChoice('Never On Sunday');

This would result in the following radio buttons:

Sometimes Always Never On Sunday

Choice: 1 2 3
The labels are not centered to take advantage of the PickList character
search procedures.

Declaration
procedure AddChoiceString(Choice: string);
Purpose
To add exit choices that will be displayed in the radio button icons.
Description
This works much like AddChoice but you can include several choices in the
Choice string. Each word in the string is treated as a separate choice.
Example
AddChoiceString('Sometimes Always Never_On_Sunday');

Declaration
procedure AddStringEntryField(Prompt: string; pRow, pCol: word;
Picture: string; fRow, fCol: word;
fWidth: byte; HelpIndex: word;
EditSt: string);
Purpose
To add a string entry field to the DialogBox.
Description
The use of this method is exactly the same as AddStringField in OPRO. The
positioning of the field is adjusted in CreateBox as necessary to center the
field just above the radio buttons. pCol and fCol are adjusted to center the
entry field inside the box in the rbHoriz mode; only their difference is
significant. pRow and fRow are only used to determine whether the prompt and
the field are on the same line or if not, which comes first. So the
difference between pRow and fRow is the only thing that is significant.

Declaration
procedure AddHeader(S: string; Posn: HeaderPosType);
Purpose
To add a header on the frame of the DialogBox.
Description
Works just like the similar method in OPRO on the dlEntry^. It can fail
because of insufficient memory.

Declaration
function GetLastChoice: word;
Purpose
Returns the number of the Choice that is selected.
Description
The exit Choices are numbered beginning with 1 in the sequence that they
appear in the Choice string in AddChoiceString. This should be called after
Process to get the exit selection.

Declaration
function GetEditedString: string;
Purpose
Returns the edited string if AddStringEntryField has been used.
Description
If no entry field has been added, it will always return a blank string.

Declaration
procedure SetTimeOut(Delay: word);
Purpose
Used to set a time out period (in seconds) for DialogBox.
Description
Sometimes it is useful to display a temporary message that is on the screen
for a fixed length of time (Delay). If the user presses a key, the timeout
feature is overridden and the DialogBox reverts to normal key and mouse
operation. If the DialogBox exits because of timeout, the GetLastChoice will
return a value of scTimeOut (presently = 99).
Example
if not MyDialog.Init(rbHoriz,1,78,2,20) then Exit;
with MyDialog do
begin
AddMessageString('Test of timeout feature.');
AddChoiceString('Ok Cancel');
SetTimeOut(10);
Process;
Code := GetLastChoice;
Done;
end;

If a key is not pressed within 10 seconds, Code = scTimeOut.
If {Enter} is pressed, MyDialog is erased and Code = 1.
If any other key is pressed, MyDialog reverts to normal operation.

Declaration
function CreateBox: boolean; virtual
Purpose
Initializes entry screen and radio buttons and adds fields.
Description
Normally CreateBox is called automatically by Process; however you may call
it separately if you want to use non-default features. If CreateBox is
called prior to Process, then it will not be called in Process. CreateBox
sizes the entry screen window based on the messages, choices and entry field
that are added. In the rbHoriz mode the radio buttons are centered at the
bottom of the window. If an entry field is added, it is centered just above
the radio buttons. In the rbVertical mode the radio buttons are at the right
hand side of the window and the entry field is placed just below the lines
of text. If all goes well, it returns true. When CreateBox exits, all
objects are initialized and ready for a call to Process or Draw. CreateBox
tries very hard to work with what you have given it to put the dialog box on
the screen either in the center or as close as possible to the position you
have defined using InitDeluxe.

Comments or suggestions are welcome. I intend to add some other field types to
DialogBox such as a Directory window.



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