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Delphi 4
Delphi 5
Delphi 6
Delphi 7
Delphi 2005
Delphi 2006
Delphi 2007
Delphi 2009
Delphi 2010

DESCRIPTION

The TRealTimeMarquee is a scrolling marquee control, and uses Windows multimedia timer for its timing needs. By this control, the marquee always runs smoothly even if your application is busy by doing some time consuming operations.

The TRealTimeMarquee control allows you to format scrolling text using a subset of HTML tags with link and image support (see supported HTML tags).

PROPERTIES

Active: Boolean
Indicating whether the marquee is running.
Interval: Integer
Determines the time interval of updating screen in milliseconds.

Items: TMarqueeCollection
Specifies items of the marquee. Each item of the collection is type of TMarqueeItem and has the following properties:

Alignment: TMarqueeAlignment
TMarqueeAlignment = (maCenter, maLeftOrTop, maRightOrBottom)
Controls the placement of the text within the marquee control.

maCenter Text is centered in the control.

maLeftOrTop For vertical marquee, text is left-justified. For horizontal marquee, text appears at the top of the control.

maRightOrBottom For vertical marquee, text is right-justified. For horizontal marquee, text appears along the bottom of the control.

Marquee: TRealTimeMarquee ^(Read-only)
Specifies the marquee control that owns the item.
Showing: Boolean ^(Read-only)
Indicates whether the item is currently visible on the screen.

Style: TMarqueeStyle
TMarqueeStyle = (msText, msHTML, msOwnerDraw)
Determines how the marquee's text is displayed.

msText The Text property contains plain text.

msHTML The Text property contains HTML formatted text.

msOwnerDraw The marquee will be drawn by OnDrawItem event handler.

Text: WideString
Specifies the text appearing in the marquee.
Tag: Integer
Stores an integer value as part of the item.

LoopCount: Integer ^(Read-only)
Indicates the number of times that all marquee items has been displayed.
LoopSpacing: TPercent
TPercent = 0..100
Determines the distance between two consequent marquee loops in percentage of the control's width (horizontal) or height (vertical). For example, when Spacing is 100 percent, the first item of the next loop appears jsut when the last item of the previous loop is left the screen.
NumLoops: Integer
Determines the maximum number of times that all marquee items should be displayed. When the LoopCount property reaches to this limit, the Active property automatically sets to False. Setting value of NumLoops property to zero, means no limit.
Orientation: TMarqueeOrientation
TMarqueeOrientation = (moHorizontal, moVertical)
Determines the direction of the marquee.
Spacing: TPercent
TPercent = 0..100
Determines the distance between two consequent marquee items in percentage of the control's width (horizontal) or height (vertical). For example, when Spacing is 100 percent, the next item appears just when the previous item is left the screen.
Step: Byte
Specifies the number of pixels that the marquee should advance on each screen update.
VisibleCount: Cardinal ^(Read-only)
Determines the number of marquee items currently visible on the control.

METHODS

procedure Lock
Prevents the control from scrolling the content.
procedure Unlock
Allows the control to scroll the content.
procedure Reset
Resets the control to start the marquee from the first item.

EVENTS

OnDrawItem: TMarqueeDrawItemEvent
procedure(Sender: TObject; Item: TMarqueeItem; Bitmap: TBitmap) of object;
Occurs when a custom draw marquee item is about to be rendered. The event handler should set Width and Height properties of the bitmap object specified by the Bitmap parameter and then draw the custom item on the Bitmap's canvas.
Note: This event does not occur in the main VCL thread.
OnImage: TMarqueeImageEvent
procedure(Sender: TObject; const Src: WideString; Image: TPicture) of object
Occurs when image of an IMG tag is required. The event handler should load the image in to the picture object specified by the Image parameter. If you do not specify an event handler for this event, the control suppose the Src parameter points to an image file and tries to load the image from the file.
Note: This event does not occur in the main VCL thread.
OnLink: TMarqueeLinkEvent
procedure(Sender: TObject; const Link: WideString) of object
Occurs when user clicks on a hyper link. If you do not specify an event handler for the event, the control tries to open the link using ShellExecute API of Windows.
OnWrap: TNotifyEvent
Occurs when the control finishes displaying all marquee items, and is about to re-start from the first item.

Supported HTML Tags

The following HTML tags and attributes are supported:

Tag Description

FONT Specifies font of the content.

Attribute Description

FACE Specifies face name of the font.

SIZE Specifies size of the font (in points). This value can be absolute or relative. A plus (+) or minus (-) signe in front of size indicates a relative size.

COLOR Specifies forecolor of the font and can be Delphi color name (without cl prefix, for example Red), hex HTML color (for example #FF0000), or short notation of hex HTML color (for example #F00).

BGCOLOR Specifies background color of the font and can be Delphi color name (without cl prefix, for example Red), hex HTML color (for example #FF0000), or short notation of hex HTML color (for example #F00).
This attribute is not part of HTML standards.

B
STRONG Renders content in bold text style.

I Renders content in italic text style.

U Renders content in underline text style.

S
STRIKE Renders content in strike-through text style.

SUP Renders content in superscript text style.

SUB Renders content in subscript text style.

SMALL Renders content in small text style.

BIG Renders content in large text style.

A Makes the content as hyper link (see OnLink event).

Attribute Description

HREF Specifies address of the link.

IMG Embeds an image in to the content (see OnImage event).

Attribute Description

SRC Specifies location of the image.

WIDTH Specifies width of the image to override (in pixels).

HEIGHT Specifies height of the image to override (in pixels).

HSPACE Specifies horizontal padding of the image (in pixels).

VSPACE Specifies vertical padding of the image (in pixels).

In addition, each tag can have the DIR attribute with LTR or RTL value which respectively renders text in left-to-right and right-to-left direction. This is useful for mixing LTR and RTL text in one line. All other tags and attributes that are not mentioned above will be ignored.

You can use any numeric HTML entitiy (for example ↔) in text. Besides that, the following special character codes are recognized:

Character Code Description

  non-breaking space

© © copyright sign

® ® registered trademark sign

™ ™ trademark sign

¹ ¹ superscript 1

² ² superscript 2 (squared)

³ ³ superscript 3 (cubed)

" " quotation mark

& & ampersand sign

< < less than sign

> > greater than sign

– – en dash

— — em dash

¯ ¯ macron, spacing macron

‘ ‘ left single quote

’ ’ right single quote, apostrophe

“ “ left double quote

” ” right double quote

• • bullet

† &dagger; dagger sign

‡ &Dagger; double dagger sign

′ ′ prime, minutes, feet

″ ″ double prime, seconds, inches

‹ &lsaquo; single left pointing angle quote

› &rsaquo; single right pointing angle quote

« « double left pointing angle quotes

» » double right pointing angle quotes

˜ &tilde; tilde sign

ˆ &circ; circumflex (or caret) sign

♠ &spades; spades suit

♣ &clubs; clubs suit

♥ &hearts; hearts suit

♦ &diams; diamonds suit

◊ &loz; lozenge

← ← left arrow

→ → right arrow

↑ ↑ up arrow

↓ ↓ down arrow

↔ ↔ left-right arrow

¬ ¬ not sign

¼ ¼ vulgar fraction one quarter

½ ½ vulgar fraction one half

¾ ¾ vulgar fraction three quarters

± ± plus-minus sign

° ° degree sign

ª ª feminine ordinal indicator

º º masculine ordinal indicator

¡ ¡ inverted exclamation mark

¿ ¿ inverted question mark

€ € euro sign

¢ ¢ cent sign

£ £ pound sign

¥ ¥ yen sign

¤ ¤ currency sign

§ § section sign

¶ ¶ paragraph sign, pilcrow sign

· · middle dot, georgian comma

µ µ micro sign

× × multipication sign

÷ ÷ division sign

Character	Code	Description
		non-breaking space
©	©	copyright sign
®	®	registered trademark sign
™	™	trademark sign
¹	¹	superscript 1
²	²	superscript 2 (squared)
³	³	superscript 3 (cubed)
"	"	quotation mark
&	&	ampersand sign
<	<	less than sign
>	>	greater than sign
–	–	en dash
—	—	em dash
¯	¯	macron, spacing macron
‘	‘	left single quote
’	’	right single quote, apostrophe
“	“	left double quote
”	”	right double quote
•	•	bullet
†	&dagger;	dagger sign
‡	&Dagger;	double dagger sign
′	′	prime, minutes, feet
″	″	double prime, seconds, inches
‹	&lsaquo;	single left pointing angle quote
›	&rsaquo;	single right pointing angle quote
«	«	double left pointing angle quotes
»	»	double right pointing angle quotes
˜	&tilde;	tilde sign
ˆ	&circ;	circumflex (or caret) sign
♠	&spades;	spades suit
♣	&clubs;	clubs suit
♥	&hearts;	hearts suit
♦	&diams;	diamonds suit
◊	&loz;	lozenge
←	←	left arrow
→	→	right arrow
↑	↑	up arrow
↓	↓	down arrow
↔	↔	left-right arrow
¬	¬	not sign
¼	¼	vulgar fraction one quarter
½	½	vulgar fraction one half
¾	¾	vulgar fraction three quarters
±	±	plus-minus sign
°	°	degree sign
ª	ª	feminine ordinal indicator
º	º	masculine ordinal indicator
¡	¡	inverted exclamation mark
¿	¿	inverted question mark
€	€	euro sign
¢	¢	cent sign
£	£	pound sign
¥	¥	yen sign
¤	¤	currency sign
§	§	section sign
¶	¶	paragraph sign, pilcrow sign
·	·	middle dot, georgian comma
µ	µ	micro sign
×	×	multipication sign
÷	÷	division sign

Note: If the HTML parser detects an invalid HTML, it will not parse the rest of HTML.

HISTORY

Version 3.5 (September 1, 2015)
- Fixed memory leak in HTML images.
Version 3.4 (March 1, 2014)
- Fixed a bug causing marquee resets when an item was changed.
Version 3.3 (November 3, 2013)
- Some minor optimizations.
Version 3.2 (November 25, 2010)
- Fixed bug in EncodeHTMLEntities function of SimpleHTML unit. The function was encoding only one special character and ignoring the rest. - Before, each marquee item had its own image cache for HTML images. Now, all marquee items use a single image cache to prevent creating/loading images more than once.
Version 3.1 (August 13, 2010)
- Added Alignment property to marquee collection items.
- Fixed the compatibility issue with Delphi 4 and 5.
Version 3.0 (August 6, 2010)
- Added LoopSpacing property to specify spacing between two consequent loops.
- Added Orientation property to define the direction of marquee either horizontally or vertically.
- Added Showing property to marquee collection items.
- Added Items.LoadFromStrings and Items.SaveToStrings methods to load/save marquee items from/to a TStrings object.
- Removed BeginUpdate and EndUpdate methods. Instead you can use Items.BeginUpdate and Items.EndUpdate methods.
- Now the OnWrap event raises in the main VCL thread.
- Codes related to parsing and displaying HTML text has been moved to the separate unit SimpleHTML.
Version 2.4 (February 5, 2010)
- Added OnMouseEnter and OnMouseLeave events.
- Resolved the compatibility issue with Delphi 5 and earlier.
Version 2.3 (October 13, 2009)
- The bug in vertical alignment of IMG tag is fixed (Thanks to dvio).
Version 2.2 (April 17, 2009)
- The AV exception caused by removing the control from the form is resolved.
Version 2.1 (April 4, 2009)
- By mistake the component was drawing plain text always in right to left direction.
Version 2.0 (March 16, 2009)
- The component redesigned to have Unicode strings and more rendering features.
- Instead of list of strings, now items are maintained as collection of marquee items. Each item can be plain text, HTML formatted text, or owner draw. The OnDrawItem event occurs when an owner draw item needs to be rendered.
- In the previous release of the component, at each time only one marquee text was visible. But now a new text may appear on the control while other items are still scrolling. The Spacing property determines the distance between two consequent items, and VisibleCount property indicates how many items are currently visible on the control.
- The control supports IMG tags in the HTML formatted text. The OnImage event occurs when an image needs to be loaded.
- Rendering order of HTML elements in the right to left direction is corrected.
- Because of optimizations done for runtime, the marquee may flicker at design time. Don't panic please!
Version 1.0 (January 18, 2009)
- Initial release.

LICENSE

The TRealTimeMarquee component is freeware. You may copy components' files AS LONG AS YOU COPY ALL OF THEM. If you want to change the source code in order to improve the component's features, performance, etc. please send me the new source code so that I can have a look at it. The changed source code should contain descriptions what you have changed, and of course your name. The only thing you MAY NOT CHANGE is the ORIGINAL COPYRIGHT INFORMATION.

DISCLAIMER

The TRealTimeMarquee component is provided "AS IS" without any warranty of any kind, either express or implied. The entire risk as to the quality and performance of the software is with you. The author is NOT liable for any DAMAGES resulting from the use and misuse of the components, especially he is NOT liable for DAMAGES that were caused BY ANY VERSION WHICH HAS NOT BEEN PROGRAMMED BY THE AUTHOR HIMSELF.

^{END OF DOCUMENT}

maCenter		Text is centered in the control.
maLeftOrTop		For vertical marquee, text is left-justified. For horizontal marquee, text appears at the top of the control.
maRightOrBottom		For vertical marquee, text is right-justified. For horizontal marquee, text appears along the bottom of the control.

msText		The Text property contains plain text.
msHTML		The Text property contains HTML formatted text.
msOwnerDraw		The marquee will be drawn by OnDrawItem event handler.