If I remember correctly, then reintroduce should help for virtual methods. The reintroduce directive suppresses compiler warnings about hiding previously declared virtual methods. Use reintroduce when you want to hide an inherited virtual method with a new one. To answer your updated question – I think it’s not possbile to hide a non-virtual constructor with … Read more
The VCL itself does not natively implement any support for MSAA. Windows provides default implementations for standard UI controls, which many standard VCL components wrap. If you need more MSAA support than Windows provides, you will have to implement the IAccessible interface yourself, and then have your control respond to the WM_GETOBJECT message so it … Read more
1. Introduction In this post I’ll try to explain the ScanLine property usage only for 24-bit bitmap pixel format and if you actually need to use it. As first take a look what makes this property so important. 2. ScanLine or not…? You can ask yourself why to use such tricky technique like using ScanLine … Read more
The only thing I have found to work well is to use the WS_EX_COMPOSITED window style. This is a performance hog so I only enable it when in a sizing loop. It is my experience that, with the built-in controls, in my app, flickering only occurs when resizing forms. You should first perform a quick … Read more
Yes, there are faster ways to do this. Your simple loop spends most of the time in cache misses. This happends because you touch a lot of data at very different places in a tight loop. Even worse: Your memory locations are exactly a power of two apart. That’s a size where the cache performs … Read more
You need to implement and register IAutoComplete2. Here’s what it looks like using a TEdit ( shades of Andreas 🙂 ): More info here, including sample code to implement all of the above. EDIT: Posting an update to provide source for a TAutoCompleteEdit component, a registration unit, package source, and a quick sample app. (The … Read more
I use the following code: procedure PatchCode(Address: Pointer; const NewCode; Size: Integer); var OldProtect: DWORD; begin if VirtualProtect(Address, Size, PAGE_EXECUTE_READWRITE, OldProtect) then begin Move(NewCode, Address^, Size); FlushInstructionCache(GetCurrentProcess, Address, Size); VirtualProtect(Address, Size, OldProtect, @OldProtect); end; end; type PInstruction = ^TInstruction; TInstruction = packed record Opcode: Byte; Offset: Integer; end; procedure RedirectProcedure(OldAddress, NewAddress: Pointer); var NewCode: TInstruction; … Read more
You don’t need RTTI. Any code has implicit access to the protected members of any class declared in the same unit. You can take advantage of this by declaring a new TWinControl descendant in the unit that needs access to that class’s members. The declaration is very simple: type TProtectedWinControl = class(TWinControl); Then type-cast any … Read more
I’m very sure that I’m POSTing the right data Since it does not work – obviously you do not (or Delphi does not – that makes no difference for server). You should start usual debugging loop: Observe reference working behaviour. Observe your program behavior Spot the difference Eliminate the difference Check if the program works … Read more
Task Manager is not the right tool to detect memory leaks. Delphi allocates large blocks of memory and keeps them later for future use, so certain increase in allocated memory is expected even after you release all resources. Any other results (and more detailed answers) can be obtained only by using specialize memory analysis tools. … Read more