Release #3:
Previous release:
Ports:
Update Notes
The primary reason for this release is a bug I found with the open location
feature: it would access deallocated memory! In addition, I've worked in a few
other changes to make writing custom LaunchBalloon() methods
easier, fixed a bug in the demo, and added two new options:
unDELAY_CLOSE works in tandem with a timeout value to delay the
action caused by the other unCLOSE_* options. This allows you to
keep a balloon active indefinately (until the user gets back from coffee break,
etc. and has time to take a look at it). For long timeout values, I'd advise
also using unSHOW_CLOSE_BUTTON so the user can still get rid of it
quickly if need be.
unDISABLE_XP_SHADOW is exactly what it sounds like: if set, that
cool dropshadow XP uses for tooltips and menus isn't shown. Note that the user
can also disable dropshadows globally, in which case this option has no effect.
I want to add some new demos, there are more things that can be done with this
than what I'm currently demonstrating, but I felt these bug fixes needed to be
released, and I'm probably too lazy to get the demos done as soon as i'd like
anyway. So, I'll do another update when they are finished. In the meantime,
Rama Krishna either has already, or will soon be releasing his .NET Version,
so there'll be plenty of Balloon Goodness around. :)
CBalloonHelp test app, running under Windows XP.
Introduction
Using CBalloonHelp
API
Important stuff
SetAnchorPoint()
SetBackgroundColor()
SetForegroundColor()
SetTitle()
SetContent()
SetTitleFont()
SetContentFont()
SetURL()
SetIcon()
LaunchBalloon()
Features
Compatibility
Internals
Updates
Related Articles
TODO
Thanks
I hate message boxes.
Or really, I hate MessageBox()s. Something about having a
form of output sooo convenient, a single function call, no need for
resources to be added, for interfaces to be designed, for any planning or
preparation at all � not even a window handle is needed (!) � seems
almost to force programmers to use it whenever there is any doubt about
what the user should know. Is there a chance a user will perform an action in
error? Better get confirmation... Just pop up a MessageBox()!
I can't delete a file in the windows explorer without having to click
through at least one MessageBox(). Am I sure? But, the file is
executable... Am i really sure? But, it might affect registered
programs... Am I really, really sure? ... If a check
box was provided to let you hide the message in the future... But that would
require extra effort, and there's this ready to use, almost good enough function
that will suffice...
But worse yet are programs that feel the need to inform you, after performing
an action that you explicitly requested, that the action has indeed been
performed, using � you guessed it � MessageBox(). Nothing wrong
with a little feedback, especially if the action had effects not necessarily
intuitive to first-time users, but to do it in a way that requires you to stop
what you're doing, (and what is sometimes worse, what the program is
doing) just to acknowledge it... That is not funny.
OK...
Enough hypocritical griping however. Solutions do exist � creating message
boxes with check boxes or �yes to all� / �no to all� buttons is not difficult.
For the purpose of feedback, displaying a short message in a status bar will
often suffice, or possibly adding a log pane. But both of these options really
only work for the main window of an application, and have other drawbacks in
terms of visibility and screen real-estate as well.
With Windows 2000, Microsoft began a practice of using balloons (of the comic
strip dialog variety) for displaying messages from system tray icons. This
seems to work quite well; when I dial into the Internet, once the connection is
made, a small icon appears in the tray, along with a balloon giving details on
my connection speed. A MessageBox() here would be inexcusable, but
a balloon is small, unobtrusive, and does not require any action on my part.
After a few seconds, it quietly fades away. Windows XP provides this feature
for many more tray icons, from system updates to the activation reminder,
adding another feature to them in the form of a close button that will dismiss
the balloon instantly, in case I'm annoyed by it and don't want to wait for it
to time out. (Windows XP also uses similar balloons in other situations, but
that fits more in line with the general XP aping of MacOS...)
Note that balloons as described above are not ToolTips. ToolTips, also in use
by tray icons by the way, serve well in their current form: small unobtrusive
pieces of text that show up when you hover the mouse over a control, and
disappear immediately upon moving the mouse away. Anyone who has used
BalloonHelp on the MacOS (Ref:
http://developer.apple.com/techpubs/mac/HIGuidelines/HIGuidelines-240.html)
should know the advantages Microsoft's ToolTips have when used for this
purpose.
With Internet Explorer 5 and later, Microsoft make the Balloon ToolTip style
available for general use (via the TTS_BALLOON style). But it is
not very simple to use, and of course not useable at all on systems without
IE5.
So get to the point already...
The point of all this of course is that I've written an easy to use balloon
control. I stress easy to use: in order to convince myself and others to go
this way, I wanted it to be as easy to pop up a help balloon as popping up a
MessageBox().
Add BalloonHelp.cpp and BalloonHelp.h in your project.
The easiest way to create a balloon is to use the LaunchBalloon() static
function:
void CBalloonHelp::LaunchBalloon(const CString& strTitle,
const CString& strContent,
const CPoint& ptAnchor,
LPCTSTR szIcon
unsigned int unOptions ,
CWnd* pParentWnd ,
const CString strURL ,
unsigned int unTimeout )
This will allocate a new CBalloonHelp object, create the window,
and show it. When the window closes, the CBalloonHelp object will
be deleted automatically. Parameters are as follows:
strTitle
strContent
ptAnchor
szIcon
unOptions
pParentWnd
strURL
unTimeout
CBalloonHelp::LaunchBalloon("BoogaBooga",
"What the hell is \"Booga Booga\" supposed to mean, anyway?",
CPoint(0,0));
CBalloonHelp::LaunchBalloon("You are holding down the right mouse button!",
"Blah", Cpoint(0,0), IDI_WARNING,
CballoonHelp::unCLOSE_ON_RBUTTON_UP|CBalloonHelp::unSHOW_INNER_SHADOW,
this, "", 0);
The first line above will show a balloon with the title �BoogaBooga� and
associated message anchored to the top left corner of the screen (point is in
screen coordinates). Ideally, you'd anchor it to something more meaningful,
such as the center of a control, or a status bar icon. The default options will
cause this balloon to disappear after 10 seconds, and to show the standard
information icon at top left, and a close button at top right.
The second line above will show a balloon, this time anchored to the top left
corner of the window represented by this, this time with the
standard warning icon. The CBalloonHelp::unCLOSE_ON_RBUTTON_UP option will
cause it to be destroyed when the right mouse button is released � if a mouse
button is being held down, then mouse input is captured, so the balloon will
close whenever the right mouse button is released. If no mouse button is held
down, the user will have to release the right mouse button somewhere in a
window owned by the same thread in order for it to close. The
CballoonHelp::unSHOW_INNER_SHADOW option will cause the balloon to be drawn
with an inner hilight and shadow... Not all that interesting, but if you're not
running on Windows XP, it's the only shadow you can get.
It is also possible to create a balloon using the Create function, in which
case you can opt not to have the object automatically deleted when the window
closes (the LaunchBalloon function always adds the option
CBalloonHelp::unDELETE_THIS_ON_CLOSE to force this, but it may not be desirable
if, for instance, you allocate a CBalloonHelp object from the stack). This
function gives much greater potential for customization as well (see below for
more info).
Complete API
"API Create">BOOL CBalloonHelp::Create(const CString& strTitle,
const CString& strContent,
const CPoint& ptAnchor, unsigned int unOptions,
CWnd* pParentWnd ,
const CString strURL ,
unsigned int unTimeout ,
HICON hIcon );
This will create and display a balloon window. Title and content override any
set for the object prior to this call. ptAnchor indicates anchor
location in screen coordinates. unOptions should be a combination
of one or more of the following:
CBalloonHelp::unCLOSE_ON_LBUTTON_DOWN
CBalloonHelp::unCLOSE_ON_MBUTTON_DOWN
CBalloonHelp::unCLOSE_ON_RBUTTON_DOWN
CBalloonHelp::unCLOSE_ON_LBUTTON_UP
CBalloonHelp::unCLOSE_ON_MBUTTON_UP
CBalloonHelp::unCLOSE_ON_RBUTTON_UP
CBalloonHelp::unCLOSE_ON_RBUTTON_UP
CBalloonHelp::unCLOSE_ON_MOUSE_MOVE
CBalloonHelp::unCLOSE_ON_KEYPRESS
CBalloonHelp::unCLOSE_ON_ANYTHING;
CBalloonHelp::unDELAY_CLOSE;
CBalloonHelp::unDELETE_THIS_ON_CLOSE
CBalloonHelp::unSHOW_CLOSE_BUTTON
CBalloonHelp::unSHOW_INNER_SHADOW
CBalloonHelp::unSHOW_TOPMOST
CBalloonHelp::unDISABLE_XP_SHADOW;
CBalloonHelp::unDISABLE_FADE
CBalloonHelp::unDISABLE_FADEIN
CBalloonHelp::unDISABLE_FADEOUT
If pParentWnd is NULL, the balloon will be anchored
in screen coordinates, and owned by the application's main window (AfxGetMainWnd()).
If there is no main window, and pParentWnd is NULL,
creation will fail. strURL if not empty will be passed to ShellExecute()
when the balloon is clicked. If not 0, unTimeout specifies the
time in milliseconds until the balloon closes automatically. And hIcon
if not NULL specifies the icon shown in the upper left corner of the balloon;
it is copied on creation, so the icon can safely be destroyed after Create()
returns.
"API SetAnchorPoint">void CBalloonHelp::SetAnchorPoint(CPoint ptAnchor, CWnd* pWndAnchor = NULL);
Sets the point to which the balloon is anchored (the point the balloon's tail
attaches to). Calling this before the balloon is created has no effect, since
the anchor is a required parameter of Create(). If pWndAnchor
is NULL, ptAnchor is assumed to be in screen
coordinates, otherwise it is assumed to be relative to the client area of pWndAnchor
"API SetBackgroundColor">void CBalloonHelp::SetBackgroundColor(COLORREF crBackground);
Sets the background color of the balloon. Can be called before or after the
balloon is created.
"API SetForegroundColor">void CBalloonHelp::SetForegroundColor(COLORREF crForeground);
Sets the foreground (borders & text) color of the balloon. Can be called
before or after the balloon is created.
"API SetTitle">void CBalloonHelp::SetTitle(const CString& strTitle);
Sets the title of the balloon. Can be called before or after the balloon is
created.
"API SetContent">void CBalloonHelp::SetContent(const CString& strContent);
Sets the content of the balloon. Can be called before or after the balloon is
created.
"API SetTitleFont">void CBalloonHelp::SetTitleFont(CFont* pFont);
Sets the font used to draw the title of the balloon. Can be called before or
after the balloon is created. The font and the CFont object are stored and
eventually deleted by the balloon; do not use either after calling this
function.
"API SetContentFont">void CBalloonHelp::SetContentFont(CFont* pFont);
Sets the font used to draw the contents of the balloon. Can be called before or
after the balloon is created. If this is called before creation, and the title
font is not explicitly set (via SetTitleFont()) then a bold
version of this font is used for the title (even if this font is already bold).
The font and the CFont object are stored and eventually deleted by the balloon;
do not use either after calling this function.
"API SetURL">void CBalloonHelp::SetURL(const CString& strURL);
Sets the URL or file to be opened by the balloon when clicked. Set to "" to
disable. Can be called before or after the balloon is created.
"API SetIcon">void CBalloonHelp::SetIcon(HICON hIcon);
Sets the icon shown at the top left of the balloon. Pass in NULL to show no
icon. Icon will not be scaled. Can be called before or after the balloon is
created.
void CBalloonHelp::SetIcon(HBITMAP hBitmap, COLORREF crMask);
Sets the icon shown at the top left of the balloon. crMask indicates
transparent color. Pass in NULL for hBitmap to show no icon. Icon
will not be scaled. Can be called before or after the balloon is created.
void CBalloonHelp::SetIcon(HBITMAP hBitmap, HBITMAP hMask);
Sets the icon shown at the top left of the balloon. hMask indicates
the transparent areas. Both parameters must be valid. Icon will not be scaled.
Can be called before or after the balloon is created.
void CBalloonHelp::SetIcon(CImageList* pImageList, int nIconIndex);
Sets the icon shown at the top left of the balloon. nIconIndex indicates
image to use. Both parameters must be valid. Icon will not be scaled. Can be
called before or after the balloon is created.
"API LaunchBalloon">void CBalloonHelp::LaunchBalloon(const CString& strTitle,
const CString& strContent,
const CPoint& ptAnchor,
LPCTSTR szIcon ,
unsigned int unOptions ,
CWnd* pParentWnd ,
const CString strURL ,
unsigned int unTimeout )
Creates and shows a balloon. This is a static function, so calling this on an
instance of CBalloonHelp is not too useful. If you need more control, create a
derived class, or use Create() and associated property functions.
See Use for more information.
-
Easy to use interface.
-
Adjusts position depending on anchor position; window will always be completely
visible, assuming content size is less than screen size.
-
Uses translucency effects if available.
-
Uses drop-shadow effect if available.
Tested on Windows XP, 2000, 98, and 95
Compiles with VC++ 6.0 / MFC 6 and VC++.NET / MFC 7
CBalloonHelp is an MFC class, derived from CWnd. The
first time a balloon is created, a window class named �BalloonHelpClass� is
registered. First, a window class with the CS_DROPSHADOW style is
registered; if registration fails, the style is removed, and registration is
attempted again. This allows use of the style on Windows XP, while avoiding
problems on previous versions of Windows.
The window is created hidden, and then the size of the content and title are
calculated. Margins and space for the tail are added to this, and the window is
sized and positioned relative to the anchor point. Finally, the window region
is set and the window is shown.
Tip: when doing shaped windows, put the shaped bits in the non-client area;
it's a lot easier to deal with if you don't have to account for that
stuff when dealing with drawing the client area.
AnimateWindow() is used for the fade-in/fade-out effects if
available and requested.
Messsage hooks are used to determine when closing mouse actions occur.
Andrew Nosenko's CAuxThunk implementation (renamed to _ThunkImpl) is used for
implementing message hooks.
8/2/02
-
Fixed bug in demo where div by zero balloon would be shown at wrong position.
-
Fixed bug where deallocated memory was accessed when using the strURL parameter
to open a file or location when the balloon was clicked.
-
Added option:
CBalloonHelp::unDELAY_CLOSE.
-
Added option:
CBalloonHelp::unDISABLE_XP_SHADOW.
5/30/02
-
Posted Maximilian H�nel's WTL port.
-
Release #2 (arbitrary number, but needed something)
-
Added support for multiple monitors
-
Added support for closing on WM_*BUTTON_DOWN messages.
-
Added support for anchoring to windows (move with parent).
-
Reworked message hook code, taken mostly from Max's WTL port.
1/23/02
-
Posted Fil Mackay's ATL port
12/31/01
-
Changed utilization of transparency (again), hopefully this will workaround
problems with Win2k
-
Altered border calculation code slightly
-
Fixed bug where no title would cause balloon to be full screen sized.
12/21/01
-
Expanded API to allow greater customization
-
Added example of balloon created manually that moves with parent window
-
Implemented keyboard hooks to allow close-on-keypress
-
Separate flags to disable fade-in/fade-out
-
Smooth scaling of small icons used for
LauchBalloon()
(on Win2k/XP only)
-
Misc. code cleanup.
12/12/01
-
Fixed bug with mouse not being released until fade-out had completed.
-
Added option for disabling fade effects; this is forced if the user has
disabled them via the control panel.
-
Added option for making balloons topmost windows.
Clean up code a bit... most of it is pretty straight forward, but documentation
could be better.
Move to straight Win32, not MFC derived class.
Add better code walkthrough to this article.
...Jan van den Baard for showing me the right way to use AnimateWindow(), and
for demonstrating how WM_NCHITTEST can be used to provide hot
tracking. Check out his ClassLib
library on CP!
...Maximilian H�nel for his WTL port, and for demonstrating therein a nicer way
to handle message hooks.
...To all the people who've provided feedback, positive and negative. It all
helps.
...To Mustafa Demirhan, for his suggestion and information on using keyboard
hooks.
...To The Code Project, for providing a useable forum for all of us.
