BorlandTalk.com Borland discussion newsgroups   Archives   FAQ   Search   Memberlist   Usergroups   Register   Profile   Log in to check your private messages   Log in  TPanel derived class Paint problem          BorlandTalk.com Forum Index -> C++ Builder (VCL Components Usage) View previous topic :: View next topic   Author Message Kent Guest Posted: Mon Apr 03, 2006 6:03 am    Post subject: TPanel derived class Paint problem I have derived a class from TPanel to custom draw the panel's borders, based on one of JD's past posts. The TPanels contain one TImage and a variable number of TSpeedButtons, with the speedbuttons added at runtime. void __fastcall TMyPanel::Paint() { Canvas->Brush->Color = clBtnFace; Canvas->FillRect( Canvas->ClipRect ); Frame3D(Canvas, Canvas->ClipRect, clBtnShadow, clBtnShadow, 1); } I have also tried the following: void __fastcall TMyPanel::PaintWindow(HDC DC) { Canvas->Handle = DC; Canvas->Brush->Color = clBtnFace; Canvas->FillRect( Canvas->ClipRect ); Frame3D(Canvas, Canvas->ClipRect, clBtnShadow, clBtnShadow, 1); } Both ways seem to work equally well. The only problem I have occurs using both methods: when the speedbutton's flat property is set to true, moving the mouse over and exiting the button leaves the bottom/right clBtnShadow raised edges behind. What can I do to stop this from happening? I'm using BCB3 Pro on XP Pro. Kent Back to top JD Guest Posted: Mon Apr 03, 2006 6:03 pm    Post subject: Re: TPanel derived class Paint problem "Kent" <kentav (AT) accessus (DOT) net> wrote: Quote: [...] void __fastcall TMyPanel::PaintWindow(HDC DC) { Canvas->Handle = DC; Canvas->Brush->Color = clBtnFace; Canvas->FillRect( Canvas->ClipRect ); Frame3D(Canvas, Canvas->ClipRect, clBtnShadow, clBtnShadow, 1); } That must be really old because I would never code that that way today. Quote: [...] when the speedbutton's flat property is set to true, moving the mouse over and exiting the button leaves the bottom/right clBtnShadow raised edges behind. You're going to have to post the whole class. ~ JD Back to top Kent Guest Posted: Tue Apr 04, 2006 3:03 am    Post subject: Re: TPanel derived class Paint problem JD, Thanks for replying. Here is the link for the post to which I was referring: http://216.101.185.148/scripts/isapi.dll/article?id=36FD8391&article=6 033574 The class is exactly the same, just copied and pasted. The only difference in my code is the "custom drawing" in the PaintWindow method. When I noticed the problem, I tried the Paint method and the problem persisted. In the main form's constructor I have the following: Panel2 = new TMyPanel(this); Panel2->Parent = this; Panel2->Width=27; Panel2->Align=alRight; Then I add TSpeedButtons to the panel and set some of their properties. Can you replicate the problem on your system? Thanks for any help you can provide. Kent Back to top Kent Guest Posted: Tue Apr 04, 2006 3:03 am    Post subject: Re: TPanel derived class Paint problem JD, Thanks for replying. Here is the link for the post to which I was referring: http://216.101.185.148/scripts/isapi.dll/article?id=36FD8391&article=6 033574 The class is exactly the same, just copied and pasted. The only difference in my code is the "custom drawing" in the PaintWindow method. When I noticed the problem, I tried the Paint method and the problem persisted. In the main form's constructor I have the following: Panel2 = new TMyPanel(this); Panel2->Parent = this; Panel2->Width=27; Panel2->Align=alRight; Then I add TSpeedButtons to the panel and set some of their properties. Can you replicate the problem on your system? Thanks for any help you can provide. Kent Back to top JD Guest Posted: Tue Apr 04, 2006 6:03 am    Post subject: Re: TPanel derived class Paint problem "Kent" <kentav (AT) accessus (DOT) net> wrote: Quote: Here is the link for the post to which I was referring: Tamarack is by session only so as soon as you closed that page, the link expired. I tried several different searches but didn't find what I thought was the right class. ~ JD Back to top Kent Guest Posted: Tue Apr 04, 2006 6:03 am    Post subject: Re: TPanel derived class Paint problem Quote: Tamarack is by session only so as soon as you closed that page, the link expired. I tried several different searches but didn't find what I thought was the right class. Sorry about that. Here is the post: From:"JD" <nospam (AT) nospam (DOT) com> Subject:Re: TCanvas and repainting Date:17 Oct 2005 16:27:47 -0700 Groups:borland.public.cppbuilder.vcl.components.using Quote: [...] What is the correct/proper way to set up a TCanvas on a TPanel and have it handle its drawing in a way that will not interfere with the other components' regular drawing Subclass the TPanel so that you can override it's PaintWindow method. For example: //------------------------------------------------------------- #ifndef MyPanelH #define MyPanelH //------------------------------------------------------------- #include <Classes.hpp> #include <ExtCtrls.hpp> //------------------------------------------------------------- class TMyPanel : public TPanel { protected: virtual void __fastcall PaintWindow(HDC DC); public: __fastcall TMyPanel( TComponent *Owner ); }; //------------------------------------------------------------- #endif //------------------------------------------------------------- #pragma hdrstop #include "MyPanel.h" #pragma package(smart_init) //------------------------------------------------------------- __fastcall TMyPanel::TMyPanel( TComponent *Owner ) : TPanel( Owner ) { } //------------------------------------------------------------- void __fastcall TMyPanel::PaintWindow(HDC DC) { // do your custom drawing here } //------------------------------------------------------------- Click File | New | Unit and save it as MyPanel. Then make it look exactly as the above and save it again. Then add the MyPanel header to the form's unit's includes and add this to the form's unit: TMyPanel *pPanel; //------------------------------------------------------------- __fastcall TForm1::TForm1(TComponent* Owner) : TForm(Owner) { pPanel = new TMyPanel( this ); pPanel->Parent = this; pPanel->Left = 10; pPanel->Top = 10; // set any other properties as needed for( int x = 0; x > Panel1->Component->Count; ++x ) { TControl *pControl = dynamic_cast<TControl*>( Panel1->Component[x] ); if( pControl ) pControl->Parent = pPanel; } delete Panel1; } //------------------------------------------------------------- The above allows you to use the IDE as usual and it allows you to *not* have to wrap the TMyPanel class into a component that you would then have to install into the IDE so that you could drop it on the form at design time. Quote: and at the same time have the least overhead? That would depend on exactly how and what you are drawing and what you define as overhead. What exactly are you trying to accomplish and how are you trying to do it? Quote: Is there a set of best practices or a sort of guide with regards to this? First and foremost, you have to stick with what works for you. When it comes to custom drawing, it's usually a matter of trade-offs. How fast is fast enough? Is it worth it to code 100 lines or more, or revert to assembler for only a slight reduction in performance? Each case is unique and needs to be approached as such. ~ JD Back to top JD Guest Posted: Tue Apr 04, 2006 9:03 am    Post subject: Re: TPanel derived class Paint problem "Kent" <kentav (AT) accessus (DOT) net> wrote: Quote: Here is the post: [...] I don't see any benifit from using that class. Everything that you're doing in the paint methods is already handled natively by the TPanel. For example: Quote: void __fastcall TMyPanel::PaintWindow(HDC DC) { Canvas->Handle = DC; Don't do that! Quote: Canvas->Brush->Color = clBtnFace; Set the Color property instead. Quote: Canvas->FillRect( Canvas->ClipRect ); If you don't override PaintWindow, this will happen automatically. Quote: Frame3D(Canvas, Canvas->ClipRect, clBtnShadow, clBtnShadow, 1); Set it's BevelInner to bvNone and BevelOuter to bvRaised. BTW: ClipRect is not always the same as Rect( 0, 0, Width, Height ). Quote: } From you original post, I'm uncertain if the problem is with the TPanel's borders or the TSpeedButton's. In either case, You can always Invalidate the TPanel when you detect CM_MOUSELEAVE. For example: protected: // User declarations virtual void __fastcall WndProc( TMessage &Message ); //------------------------------------------------------------- void __fastcall TMyPanel::WndProc( TMessage &Message ) { if( Message.Msg == CM_MOUSELEAVE ) { Invalidate(); } TPanel::WndProc( Message ); } //------------------------------------------------------------- ~ JD Back to top Kent Guest Posted: Wed Apr 05, 2006 5:03 am    Post subject: Re: TPanel derived class Paint problem Quote: I don't see any benifit from using that class. Everything that you're doing in the paint methods is already handled natively by the TPanel. For example: I plan to do more drawing than the example code shows and use different colors than the bevel properties allow. Quote: void __fastcall TMyPanel::PaintWindow(HDC DC) { Canvas->Handle = DC; I pasted in this line from another "PaintWindow" post. I'm curious, though, as to what circumstances would require using this parameter. BTW: Quote: ClipRect is not always the same as Rect( 0, 0, Width, Height ). Thanks for pointing this out. Quote: From you original post, I'm uncertain if the problem is with the TPanel's borders or the TSpeedButton's. In either case, You can always Invalidate the TPanel when you detect CM_MOUSELEAVE. I tried that and it works, but it flickers the whole panel of speedbuttons when moving from one speedbutton to the next. In case I wasn't clear in my first post, the flat-style speedbuttons stay "raised" on the right and bottom edges only when moving from one speedbutton to the previous speedbutton (to the left) but do not stay raised when moving to the right. It seems strange that a simple class derivation introduces this behavior. Thanks for your interest. I appreciate it. Kent Back to top JD Guest Posted: Wed Apr 05, 2006 10:03 am    Post subject: Re: TPanel derived class Paint problem "Kent" <kentav (AT) accessus (DOT) net> wrote: Quote: I don't see any benifit from using that class. [...] I plan to do more drawing [...] Then I would suggest that you use a TBitmap for that, sizing it to the same dimensions as the panel and doing all of your drawing on it instead of the Panel's Canvas. Then, in the PaintWindow method, use the TCanvas::CopyRect method to paint the bitmap. It's the fastest that you can get using a pure VCL solution and insignificantly slower than using the win32 API BitBlt. I recall that you also have a TImage in there as well. Since you're already subclassing TPanel, you could add that image to the resource and use another TBitmap instead. Other considerations are if you configure the panel to be resizable by setting it's Align property or by using some other OnResize event and manually changing the panel's size. If you going this way, intercept WM_WINDOWPOSCHANGED and change the bitmaps size and redraw it. Quote: and use different colors than the bevel properties allow. Draw that once onto the bitmap unless it's going to be a number of different colors. Quote: Canvas->Handle = DC; [...] I'm curious, though, as to what circumstances would require using this parameter. In this class, TPanel's PaintWindow method has been overridden by your PaintWindow method and your method does not use it and does not call it's inherited method which would use it. Quote: [...] Invalidate the TPanel when you detect CM_MOUSELEAVE. I tried that and it works, but it flickers the whole panel of speedbuttons when moving from one speedbutton to the next. I overlooked that that message would be sent even if the mouse was still within the panel's bounding rect but that's easy to fix. Quote: [...] speedbuttons stay "raised" [...] It seems strange that a simple class derivation introduces this behavior. It's because the code that I posted isn't correct. The VCL sends CM_MOUSELEAVE down it's Parent chain and I didn't check to see if the message was intended for the TPanel or one of the other controls that it's parenting. The following sample also includes checking to see if the mouse is really outside the panel's bounding rect before it Invalidates the entire panel (even though I don't think you'll need it for the panel): //------------------------------------------------------------- void __fastcall TMyPanel::WndProc( TMessage &Message ) { if( Message.Msg == CM_MOUSELEAVE ) { TControl *pControl = reinterpret_cast<TControl*>( Message.LParam ); TSpeedButton *pButton = dynamic_cast<TSpeedButton*>( pControl ); if( pButton ) // it's for a speedbutton { // repaint the button pButton->Invalidate(); } else // it's for the panel { TRect R; TPoint P; ::GetWindowRect( Handle, &R ); ::GetCursorPos( &P ); if( !::PtInRect(R,P) ) Invalidate(); } } TPanel::WndProc( Message ); } //------------------------------------------------------------- ~ JD Back to top Kent Guest Posted: Thu Apr 06, 2006 7:03 am    Post subject: Re: TPanel derived class Paint problem The speedbuttons' stay raised when moving the mouse within the panel from button to button. They invalidate correctly when moving off of the panel. Recall that only the bottom and right edges stay raised, the top and left edges lower as they should, and this only occurs when moving the mouse leftward. One thing I have noticed: if I don't override the PaintWindow method, the buttons behave correctly, minus my custom drawing of course, regardless of whether I override WndProc. If I override PaintWindow but include a PaintWindow call after my custom drawing, the buttons behave correctly but of course my drawing is negated. For some reason, custom drawing appears to cause a problem for the speedbuttons. Kent Back to top JD Guest Posted: Thu Apr 06, 2006 3:03 pm    Post subject: Re: TPanel derived class Paint problem "Kent" <kentav (AT) accessus (DOT) net> wrote: Quote: [...] For some reason, custom drawing appears to cause a problem for the speedbuttons. I do not see that behavior with the following. If you don't find a solution in the sample, then you need to post your entire class. //------------------------------------------------------------- __fastcall TForm1::TForm1(TComponent* Owner) : TForm(Owner) { new TMyPanel( this ); } //------------------------------------------------------------- //------------------------------------------------------------- #ifndef Unit2H #define Unit2H //------------------------------------------------------------- #include <Classes.hpp> #include <Buttons.hpp> //------------------------------------------------------------- class TMyPanel : public TPanel { protected: virtual void __fastcall PaintWindow(HDC DC); virtual void __fastcall WndProc( TMessage &Message ); private: typedef TPanel inherited; public: __fastcall TMyPanel( TComponent* Owner ); __fastcall ~TMyPanel(); __published: }; //------------------------------------------------------------- #endif //------------------------------------------------------------- #include <vcl.h> #pragma hdrstop #include "Unit2.h" #pragma package(smart_init) //------------------------------------------------------------- __fastcall TMyPanel::TMyPanel(TComponent* Owner) : TPanel( Owner ) { Parent = dynamic_cast<TWinControl*>( Owner ); Left = 10; Top = 10; Width = 200; Height = 200; Color = clWhite; for( int x = 0; x < 5; ++x ) { TSpeedButton *pButton = new TSpeedButton( this ); pButton->Parent = this; pButton->Left = 10 + (pButton->Width + 10) * x; pButton->Top = 10; pButton->Flat = true; } } //------------------------------------------------------------- __fastcall TMyPanel::~TMyPanel() { } //------------------------------------------------------------- void __fastcall TMyPanel::PaintWindow(HDC DC) { Canvas->FillRect( Rect(0,0,Width,Height) ); } //------------------------------------------------------------- void __fastcall TMyPanel::WndProc( TMessage &Message ) { inherited::WndProc( Message ); } //------------------------------------------------------------- ~ JD Back to top Kent Guest Posted: Thu Apr 06, 2006 11:03 pm    Post subject: Re: TPanel derived class Paint problem It's working now. Many thanks. Kent Back to top Display posts from previous: All Posts1 Day7 Days2 Weeks1 Month3 Months6 Months1 Year Oldest FirstNewest First         BorlandTalk.com Forum Index -> C++ Builder (VCL Components Usage) All times are GMT Page 1 of 1   Jump to: Select a forum C++ Builder Newsgroups----------------C++ BuilderC++ Builder (ActiveX)C++ Builder (Announcements)C++ Builder (Command Line Tools)C++ Builder DatabasesC++ Builder Databases (ADO)C++ Builder Databases (Desktop)C++ Builder Databases (InterBase Express)C++ Builder Databases (Multi-Tier)C++ Builder Databases (SQL Servers)C++ Builder (Graphics)C++ Builder (IDE)C++ Builder (Internet)C++ Builder (Internet Socket)C++ Builder (Internet Web)C++ Builder (Jobs)C++ Builder (Language)C++ Builder (Language C++)C++ Builder (Compatibility with MFC)C++ Builder (Native API)C++ Builder (Non-Technical)C++ Builder (Students)C++ Builder (Third Party Tools)C++ Builder (Upgrade)C++ Builder (VCL)C++ Builder (VCL Components Usage)C++ Builder (VCL Components Development)C++ Builder (VCL Usage)C++ Builder (WinAPI)C++ Builder Installation Delphi Newsgroups----------------Delphi (General)Delphi ActiveX Controls UsageDelphi ActiveX Controls DevelopmentDelphi As400Delphi DatabasesDelphi Databases (ADO)Delphi Databases (dbExpress)Delphi Databases (Desktop)Delphi Databases (InterBase Express)Delphi Databases (Multi-Tier)Delphi Databases (SQL Servers)Delphi DeploymentDelphi GraphicsDelphi IDEDelphi InternationalizationDelphi InternetDelphi Internet Isapi-WebBrokerDelphi Internet WebSnapDelphi Internet WinsockDelphi JobsDelphi Language BASMDelphi Language ObjectPascalDelphi Model Driven Architecture (General)Delphi Model Driven Architecture (Third Party)Delphi MultimediaDelphi Native APIDelphi Non-TechnicalDelphi ObjectPascalDelphi OLE AutomationDelphi OO designDelphi OpenToolsAPIDelphi Reporting-ChartingDelphi RTLDelphi StudentsDelphi TeamSourceDelphi Thirdparty ToolsDelphi Thirdparty Tools (General)Delphi Thirdparty Tools (IntraWeb)Delphi Thirdparty Tools (RaveReports)Delphi UpgradeDelphi VCLDelphi VCL ComponentsDelphi VCL Components UsingDelphi VCL Components WritingDelphi WebServices SOAPDelphi WinAPIDelphi XMLDelphi Installationcomp.lang.pascal.delphi.components.misccomp.lang.pascal.delphi.components.usagecomp.lang.pascal.delphi.components.writingcomp.lang.pascal.delphi.databasescomp.lang.pascal.delphi.misccomp.sources.delphi JBuilder Newsgroups----------------JBuilderJBuilder AnnouncementsJBuilder Applet IssuesJBuilder As400JBuilder CompilerJBuilder CORBA/RMIJBuilder DatabasesJBuilder DB SwingJBuilder DebuggerJBuilder DeploymentJBuilder DocumentationJBuilder EnterpriseJBuilder HandheldJBuilder IDEJBuilder JavaJBuilder JavaAPIJBuilder Java LanguageJBuilder Java SwingJBuilder Java BeansJBuilder Java Beans UsageJBuilder Java Beans DevelopmentJBuilder JBCLJBuilder JDataStoreJBuilder JobsJBuilder LinuxJBuilder MacintoshJBuilder & MobileSetJBuilder MultiLingual AppsJBuilder Non-TechnicalJBuilder OpenToolsJBuilder Servlets (JSP)JBuilder StudentsJBuilder Team DevelopmentJBuilder Thirdparty ToolsJBuilder UpgradeJBuilder Installation InterBase Newsgroups----------------InterBaseInterBase Bug DiscussionInterBase GeneralInterBase IBConsoleInterBase OpenSourceInterBase ReplicationInterBase SQLInterBase ThirdpartyInterBase Installation Miscellaneous Borland Newsgroups----------------AppCenterAppServerEnteraVisiBroker  You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum Powered by phpBB © 2001, 2006 phpBB Group SEO toolkit © 2004-2006 webmedic.