Components	Programs	Tips	Games	Links

RAD Studio XE4 is released !!
It delivers multi-device development for Intel and ARM devices, including Apple iPhone, iPad, iPad mini, iPod touch, Windows and Mac. Try it! http://embt.co/RADXE4Trial

Components & Utils

Interactive basic viewer
It's a long time I've been looking for a "basic interactive report viewer", inherited from TGraphicControl, with little overhead, and html independant.
Not finding exactly what I wanted from outside, here is what I did:
1. digged into QuickReport components source code.
2. adapted their QRX preview /browser, in modifying the layout.
3. proposed to QBS Software (QuickReport publisher) some necessary modifications to the QuickReport source code
.. and voilà, here is the interactive report I was after -> Interactive basic viewer.

Want some more details ? download [this].
NB: this demo requires QuickReport 5.05.2 build2 or upper

TCsvTransform class helper (ver 1.3)

Did'nt you ever need to simply store your data in a .csv (Comma Separated Value) format, then load it in a TClientDataSet and play (CRUD) with it .. and then save it back to the same (or other) .csv file ? Delphi does not provide any built-in access to .csv data, but a TCsvTransform class helper makes it simply come true.
How ? .. look at the example [here]

TFocusComboEdit controls (ver 6.1)

Like TComboEdit or TDateEdit but showing a side-button displayed *only when the control has the focus*.
Caution : These controls are TJvCustomXxxxEdit descendants and require JVCL /RxLib installed.
version 6.1 supports LiveBindings -> can be used directly assigning TFocusComboEdit to TLinkControlToField.Control property in object inspector.

TEventsHandler class

enables to run multiple events at once, simulating event multi-casting. example of use :

var
   aEventsHandler: TEventsHandler;
begin
   // create a new TEventsHandler with 'CreateNextForm' procedure as its main event
   aEventsHandler := TEventsHandler.Create(CreateNextForm);
   try
   // set 'Validate' procedure to be run before aEventsHandler's main event 
   aEventsHandler.AddLinkedEventsHandler(odBefore, TEventsHandler.Create(Validate));


   // set 'ClearStatusBar' procedure to be run after aEventsHandler's main event 
   aEventsHandler.AddLinkedEventsHandler(odAfter, TEventsHandler.Create(ClearStatusBar));


   // run all events at once in the specified order
   aEventsHandler.Execute;
   finally
      aEventsHandler.Free;
   end;
end;

Vigenere encoding unit

simple string encoding using Vigenere algorithm

Ascii2XML utility (ver.1.1)

enables to transform any Ascii /flat file with fixed length fields to a XML file, according the template of your choice.
For using it, follow these steps:

• get both files: the Ascii /flat file you want to convert (you may call it source.txt), and the template file you have defined (you may call it template.xml)
• open your Delphi IDE and compile AsciiToXML.dpr: you will get AsciiToXML.exe
• in cmd /dos console, run : "Ascii2XML.exe -source source.txt -template template.xml -target target.xml" (where target.xml is the name of the file to be created).
• now, you have get target.xml -> open it and look how it looks like

Nb: Requires JCLStrings.pas (from Jedi Component Library) and UParseReplace.pas

TEditableCtrlHolder (ver.3.3)

TEditableCtrlHolder is a data validator of any 'TEditableCtrl'(1) controls of your TForm. For each of TEditableCtrl, you can set their DataType, MaxLength and NullForbidden property. Check the validity of what you entered into each TEditableCtrl against the properties defined above. You can also loop into all TEditableCtrl to check if the entered values have been modified.
Version2 adds support to RxLib controls (TRxCheckListBox).
Version3 adds a OnValidate event-handler + support RxLib date-time picker controls (TDateEdit and TDBDateEdit)

(1): a TEditableCtrl can be any of editable controls, ie TEdit, TComboBox, TListBox, TCheckBox, TMemo, ..

For using it, follow these steps:
1. add EditableCtrlHolder.pas to your 'custom user package', compile your package.
2. open the demo project

TAlignedEdit3

derived of TAlignedEdit from Peter Below (TeamB) that enables left, center or right justification of the text in a TEdit. This version enables text focusing when the TEdit becomes active, by removing the multi-line capability.

TDBTreeView (ver.1.04)

Represents TDataSet records in a standard TTreeView.
click [here] for the screenshot

for a Delphi5 compatible version, click [here]

TMELabel (ver.3.0)

Like a TLabel component with a MEFont property that sets the font on CMMouseEnter Windows message. Usefull with AboutBox type forms, when you want to link your TLabel with internet.
Nb: may be same component /behaviour as TJvLinkLabel from JVCL

GETVALUE function for QuickReport

Enable to refer to other TQRPrintable controls (TQRExpr or TQRLabel) to get their value.

Usefull when you don't want to repeat TQRExpr expression every time you want to use it in your calculations.
To use it:

1. add this unit to your 'custom user package', compile your package.
2. put a TQRExpr on your TQuickReport, and set it's function property as 'GETVALUE([TQRPrintable name])'.

Parse & Replace utility (ver.2)

You simply want to parse your html file that contains some custom tags, and replace these tags by the required strings.
When used with TPageProducer, advantage of this method comparing with using the TPageProducer's OnHTMLTag event handler:

• HTML tags are handled in the same procedure as the Response.Content procedure. This prevents from using external variables, avoids multiple 'if then else' in the OnHTMLTag procedure, and make a more compact and quick program.
• better control of the parse & replace by using the internal Delphi parser CopyPrsr (uses CopyPrsr;).
• enables to chose the way you're going to replace in case the replacement tag is not found : or it is replaced by a null string, or it does not replace it and keeps the original <TagName>

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Programs

Many programs are arleady built. Among them:

Executive dash-board: severall 'dash-board' based products are available, depending on your power /autonomy requirements:

1. application fully integrated dash-board: all the reports are integrated in the application code.
2. selectable dash-board: all the reports are available in opening external files.
3. 'visual customizable' dash-board: all the reports are available in opening external files. You can build these files yourself with 'drag and dropping' components in a form. No line of code is at this level required.
4. 'fully customizable' dash-board: all the reports are available in opening external files. You can build these files yourself with a fully independant 'report-designer'. The 'report-designer' enables you to build wysiwyg forms, and to write genuine Pascal-Delphi script on all the event handlers needed. Creating such a report can require development capabilities.

Synoptic of all dash-board's capabilities		Type of dash-board
		application fully-integrated	selectable	visual customizable	fully customizable
user's report latitude	print /preview
	select report	no
	design report	no	no
	script on report	no	no	no

In anyway and as a preliminary, these dash-boards must be connected to any either specific or open database, the one of your entreprise.

Scrivitt ™: a program that enables to build standardised letters, simply in adding custom paragraphs.

Document-Explorer: Store your documents in a folder, and organize them as you wish with my TDBTreeView component.

Archieve-Explorer: Store your favourite magazines in the programm, and search them with the fields and key-words of your choice.

BdCC: a front-office configurator to your ERP, and add comprehensiveness and security to your business.

BCRx: a web application that enable order entry and query +e-mail communication between customer and company.

Data Dictionnary: a simple data-dictionnary management software. Store your data in the required XML format, and view /filter them in your browser with the required presentation. Implemented with Delphi +XML +XSLT.

Reminder: don't forget what you and your co-workers have planned !!
1. setup an open and unique database with the events you (or your co-workers) want to be reminded for
2. receive at the right time an e-mail reminding you the event.
NB: for more infos, please contact me

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Tips

Vanishing /unstiking component property value issue
Have not you ever been in the situation where, from the IDE, you set a property value for one of the component used, then test your program, be happy with it, save it, then re-open it ... and noticing that the value that you set for your component's property has changed ?
Here can be the reason:
1. if you set from your IDE the same propertie's value as the default one, then Delphi will not save the value in the .dfm at the time you will save your project.
2. the problem raises when you re-open your project : as no propertie's value is specified in the .dfm, the propertie's value that will appear in your object inspector is the one set in your component's constructor (if one set), or the default for the propertie's type.
When you build your own components and you want to set default for properties, be carefull to be consistent with the value given in the constructor.
Whether you use your own components or third party components, one good way to notice this trap, is to closely look at how properties are displayed in the object inspector. If the values are displayed in normal weight font, it means your propertie's value fits with its default. If the values are displayed in bold font, it means your propertie's value differs from the default, or that no default have been set.
Thus, when you first drop your component on your form, have precisely a look at a property displayed in bold, and that becomes in normal weight when changing manually its value.

LiveBinding TObject 
Delphi is an IDE that enables OOP (Object Oriented Programming) and designs the user interface. Hence why not presenting the evidence : "editing TObject instances on a form".
Object (TObject's instance) can be of a simple TObject class, or of a more complex type like a TObjectList<T>. The UI controls that will handle the display do not need being data-aware controls.
LiveBindings makes this possible, using TBaseObjectBindSource descendant.
Downloadable demo project group (below) shows :
- simple object (TObject) binded to control - FireMonkey project -,
- object list (TObjectList<T>) binded to control,
- two object lists (TObjectList<T>) linked in a master /detail relation, both binded to a TStringGrid.

Want some more details ? download [the demo project group].

import /export with XML 
The question is quite frequently asked all around and is sometimes answered with complex structures /process .. and the question is : "how to import XML data in my RDB (relational database), then edit them (CRUD -create, update, delete-) using standard UI controls, then export them back to a potentially other XML format ?".
Of course the question can be only any part of the above, ie "how to (only) import from XML" or "how to (only) export to XML".
The answer is quite simple if you use standard VCL components /structure, that are:
For accessing data: TSQLConnection, TSQLDataSet, TDataSetProvider, TClientDataSet.
For transforming data: TXMLTransformClient or TXMLTransform.
For displaying data: either data-aware controls (TDBxxx), or standard VCL UI + LiveBindings controls.

Want some more details ? download [this].
NB: this demo requires SQLite dbExpress driver provided with XE3 Professional (or higher)

deFocusControl data event in LiveBindings
Posting a record with a null value for a required field fires a 'database error' exception. Before this exception is being fired, a procedure TField.FocusControl; is executed. The intention behind that is to set focus on the UI control linked with this TField, highlighting it for further correction (ie or cancel the edit, or post a non null value)
LiveBindings does not support the deFocusControl data event (ie procedure FocusControl(Field: TFieldRef); is absent in Data.Bind.DBScope TDataLink desendants), probably because TBindLinkDataLink is control-agnostic.
To overcome this, traditional DB-aware architecture comes to rescue : simply create a TFieldDataLink that will hold the link between LiveBinded DataSource and the UI control, like

  with TFieldDataLink.Create do
  begin
  	Control := aEdit;
  	FieldName := 'aField';
  	DataSource := BindSourceDB1.DataSource;
  end;
  

Want more details through a live example, download [this].

Monitoring SQLite® database
With RAD Studio XE3®, Embarcadero added native SQLite database driver within their dbExpress framework. XE3 feature matrix says : "New in XE3! TSQLMonitor support for SQLite".
This requires some tweaks (via the Object Inspector) in the current TSQLConnection : under SQLiteConnection.Driver property, add a DBXTrace Delegate Driver.

Want more details through a live example, download [this]

Generic classes: through another example of composition, typecasting avoiding
Each time there's a novelty in the language, I'm wondering how this is going to be useful in my current /coming projects.
With Generics (or parametrized types), one obvious with it is that it flattens class hierarchies: instead of 2 levels and multiples classes, you can get the same done with only one *generic* class.
But another clean-code plus is that you can avoid typecasting.

How ? .. look at the example [here]

Anonymous Method use case
Delphi 2009 came with some novelties among them 'Anonymous Method' (AM). Reading litterature about it made me think "nice .. but what for specific use may I need it ?" or in other words "what stuff cannot be made without it (AM) easily or nicely ?".
After searching and searching again, I found a situation where AM makes a more concise /readable code : when you want that a procedure variable be declared in the local context (not in the application scope).

For more details, download the demo [here]

Sometimes you need make communicate 2 applications on the same PC *without the hassle of a middleware layer*.
It's very easy : on the Sender application, send the message with [Winapi.Windows.SendMessage] procedure; on the Receiver application, create a procedure that will capture the message; the link between both application procedures will be the message Id (integer).

Download a simple demo [here]

How about using records instead of objects
since Delphi7, records are more alike objects (read this). But the advantage of using records instead of objects is that you don't need to create them. And , of course, if you don't have to create them, you won't need to free them.
For frequently used entities, this leads to increasing run-time performance, with gaining in readability.
Let's look at an example:

1. declaring a record:

   TFieldListRecord = record
   private
     FItems: array of TFieldRec;
     function GetCount: integer; inline;
   public
     procedure Load(const aJvCsvTableName: TFileName; const KeyFields: string; KeyValues: Variant);
     function IndexOf(const s: string): integer;
     property Count: integer read GetCount;
     procedure SetItem(const FieldName: string; const FieldValue: Variant);
     function GetItem(const FieldName: string): Variant;
    function TransformToXML(const RootTag: string): string;
   end;

2. using this record:

var
   FL: TFieldListRecord;
begin
   FL.Load(aFile, 'id', 10); //no need a Constructor
   Edit1.Text  := FL.GetItem('name');
end;

How to add fields to a TDataSet at run-time

  with TStringField.Create(aDataSet) do // create a TStringField, but can be any other field.
  begin
  	FieldName := 'aFieldName';
  	FieldKind := fkLookup;
  	DataSet := aDataSet;
  	Name := DataSet.Name + FieldName;
  	KeyFields := 'aKeyFields';
  	LookupDataSet := 'aLookupDataSet';
  	LookupKeyFields := 'aLookupKeyField';
  	LookupResultField := 'aLookupResultField';

 	aDataSet.FieldDefs.Add(FieldName, TStringField, 25, False);
  end;

WebSnap™ simple project
Have you ever heard of WebSnap™ technology being deprecated by CodeGear /Embarcadero®?
I hope they won't do that, because WebSnap™ is a really nice technology to work with if you have any web development to do with Delphi.
Here is a simple project /tutorial that shows some things that are neither hard to understand nor to implement, and that you simply cannot do with WebBroker framework.

[here] the source code of the project.

How to get selected a text drawn on a TCustomControl descendant, depending on mouse click:

[here] the source code of the example and the component.

How to buid an intranet search engine using MS index server and ADO DB connection

Main steps will be to:

1. add to MS index server configuration pane the catalogs you want to scan. [click here for more details].
2. check that both IIS and MS index server are running. [click here for more details]
3. develop a simple Delphi CGI application that will use ADO DB connection for accessing to MS index server database.

Details of 3. are following:

• Nb: for Delphi versions that do not support ADO, download and install the excellent TaoADODataSet components from http://www.alohaoi.com/Software.
for adapting to MS index server field type, modify the aoADODB.pas, procedure TaoADODataSet.InternalInitFieldDefs.
click here for more details click here for collapsing
Copy this and paste it on line #4447:

if (FADOConnection.Provider = 'MSIDXS') then
case FADORecordSet.Fields.Item[i].Type_ of
0 : FieldType:= ftUnknown; {adEmpty 0 No value was specified}
2 : FieldType:= ftInteger; {adSmallInt 2 A 2-byte signed integer}
3 : FieldType:= ftInteger; {adInteger 3 A 4-byte signed integer}
4 : FieldType:= ftFloat; {adSingle 4 A single-precision floating point value}
5 : FieldType:= ftFloat; {adDouble 5 A double-precision floating point value }
6 : FieldType:= ftCurrency; {adCurrency 6 A currency value (8-byte signed integer scaled by 10,000)}
7 : FieldType:= ftDateTime; {adDate 7 A Date value}
8 : FieldType:= ftString; {adBSTR 8 A null-terminated character string (Unicode)}
9 : FieldType:= ftUnknown; {adIDispatch 9 A pointer to an IDispatch interface on an OLE object }
{$IFNDEF NEED_DBTABLES}
10 : FieldType:= ftLargeInt; {adError 10 A 32-bit error code}
{$ELSE}
10 : FieldType:= ftInteger;
{$ENDIF}
11 : FieldType:= ftBoolean; {adBoolean 11 A Boolean value}
12 : FieldType:= ftString; {adVariant 12 An OLE Automation Variant}
13 : FieldType:= ftUnknown; {adIUnknown 13 A pointer to an IUnknown interface on an OLE object}
14 : FieldType:= ftFloat; {adDecimal 14 An exact numeric value with a fixed precision and scale}
17 : FieldType:= ftInteger; {adUnsignedTinyInt 17 A 1-byte unsigned integer}
16 : FieldType:= ftInteger; {adTinyInt 16 A 1-byte signed integer}
18 : FieldType:= ftInteger; {adUnsignedSmallInt 18 A 2-byte unsigned integer}
19 : FieldType:= ftInteger; {adUnsignedInt 19 A 4-byte unsigned integer}
20 : FieldType:= ftInteger; {adBigInt 20 An 8-byte signed integer}
21 : FieldType:= ftInteger; {adUnsignedBigInt 21 An 8-byte unsigned integer}
72 : FieldType:= ftUnknown; {adGUID 72 A globally unique identifier (GUID)}
128: FieldType:= ftTypedBinary; {adBinary 128 A binary value}
129: FieldType:= ftString; {adChar 129 A String value}
130: FieldType:= ftString; {adWChar 130 A null-terminated Unicode character string }
131: FieldType:= ftFloat; {adNumeric 131 An exact numeric value with a fixed precision and scale}
132: FieldType:= ftUnknown; {adUserDefined 132 A user-defined variable}
133: FieldType:= ftDate; {adDBDate 133 A date value (yyyymmdd), contributed by David Harlowe }
134: FieldType:= ftTime; {adDBTime 134 A time value (hhmmss) - contributed by Kim Madsen}
135: FieldType:= ftDateTime; {adDBTimeStamp 135 A date-time stamp (yyyymmddhhmmss plus a fraction in billionths)}
139: FieldType:= ftFloat; {adVarNumeric 139 - contributed by Kim Madsen.}
200: FieldType:= ftString; {adVarChar 200 A String value (Parameter object only)}
201: FieldType:= ftMemo; {adLongVarChar 201 A long String value (Parameter object only)}
202: FieldType:= ftString; {adVarWChar 202 A null-terminated Unicode character string (Parameter object only)}
203: FieldType:= ftMemo; {adLongVarWChar 203 A long null-terminated string value (Parameter object only)}
204: FieldType:= ftUnknown; {adVarBinary 204 A binary value (Parameter object only)}
205: FieldType:= ftBlob; {dLongVarBinary 205 A long binary value (Parameter object only)} // changed for BlobSupport by Heiko Wenzel
else FieldType:= ftUnknown;
end;
Nb: to avoid this, we could look at modifying directly the data type entry values in MS index server property pane. But this must be confirmed.


• Open the simple CGI search project and compile it (not run) to c:\inetpub\scripts directory. Nb: don't change this path unless you do the same within your search.htm file.
  For Delphi versions that do not support ADO and have installed the third-party ADO library (above), you can download the search project here.
• open search.htm with your favorite web browser and test your new custom intranet search engine ..

How to check memory leaks on a CGI web application (use Delphi5 professional)
NB: with higher versions of Delphi, use FastMem memory checker and the IDE web app debugger

• Install Gabriel Corneanu CGI debugger. (get it from here)
• Install Vincent Mahon excellent memory leaks checker. (get it from here)
• On your CGI application (.dpr), do as follows:
  - activate both CGI debugger and memory leaks checker. Nb: see respective documentations for that.
  - set application's parameter to 'debug' (not 'debug loop')
• run (not only compile) your .dpr
• open your web browser and call the url that you want to check
• If some memory leaks still exist in your application, a log document will pop-up telling you where the leaks stay.

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Games

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Links
Tutorials
Delphi About	my favourite ..
Delphi - Club d'entraide des développeurs francophones	web site in french
Embarcadero - RAD in Action	learn from experts
CodeRage downloads	videos
Libraries & Components
Delphi Super Page	general
Torry's Delphi Pages	general
Project Jedi	library
QuickReport	reporting
TeeChart	charting
Newsgroups & Forums
Search CodeGear* Newsgroup Database	newsgroup search engine
Delphi Newswhat.com	newsgroup search engine
Google groups	newsgroup search engine
Delphi Newsgroups	newsgroup via http
Delphi Newsgroups	newsgroup via news protocol
Embarcadero
Embarcadero Resource Center	resources
Embarcadero Developer Network (EDN)	community
EDN - CodeCentral	library
EDN - QualityCentral	report bug
RAD Studio documentation	documentation
Online Help for Delphi XE4	documentation

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Updated on may 23rd 2013