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Anders Melander

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Anders Melander last won the day on March 10

Anders Melander had the most liked content!

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    Delphi 10.2 Tokyo

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  1. Anders Melander

    Delphi compiler need to be opensourced

    I'm pretty sure many of the countries on the receiving end of US' forced friendship has a different view on that. Look to me like the US is actually also guilty of most of the issues you listed. I don't mind the US looking after its own interests, just don't pretend it's doing anything but that. China is a complex issue. Sure it's bad in some areas, but it's slowly improving. It's a huge country and rapid change would cause the country to implode.
  2. Anders Melander

    Delphi compiler need to be opensourced

    Didn't you mean to capitalize "US"? And on that note I can't see how what China is trying to do is different from what the US is already doing to the rest of the world...
  3. Anders Melander

    Delphi compiler need to be opensourced

    It's not possible to downvote in JIRA.
  4. Anders Melander

    Use graphics32 to draw rounded rectange with gradient + border

    And have you looked at the Polygon and Gradient examples?
  5. @Dalija Prasnikar I agree with your characterization but in some cases I find that composition is better suited than inheritance even though inheritance would be more natural. For example if I were to create a list of TSomething it would be tempting to use TList<T> as a base class, Problem is that it might give me too much. If I only need an Add method, a Count and an array property, then composition is probably better (I guess one could call it inheritance through composition). I've seen too many examples of inheritance (not just from TList) where most of the inherited methods doesn't make any sense and would break the application if used.
  6. Anders Melander

    Check for override

    OK then, let me spell it out; In regular applications or even simple libraries individual braking changes are probably relatively easy to locate and fix. The TStream change for example could almost have been made with search/replace, but I guess they thought that the backward compatibility solution was safe enough that they didn't need to make it breaking. In retrospect, although I never personally got bitten by it, they should have marked the old overload as deprecated to flag that ppl should fix their code or else. FWIW I don't think the TStream method is fragile. From what I can see it's very robust. For a large framework the situation can be different. A framework has an API and therefore a contract with the users of the framework. A breaking change in the RTL that lies below the framework can mean that the break propagates to the API of the framework. For example I just yesterday finished updating my local copy of a framework that sits on top of DevExpress from a two year old version of DevExpress to the latest version. DevExpress changed the type of some properties from TBitmap to TdxSmartGlyph and since the framework exposed those same properties as TBitmap it got stuck on that old version. If the framework had followed suit and also changed the type, then it again would have broken the code of hundreds of customers (the users of the framework) with no gain to them. The company that with this particular framework is still stuck on that old version of DevExpress since they no longer have have the in-house expertise to solve the problem and you can bet they would have preferred a non-breaking change. Another example is systems with a plethora of applications and millions of LOC. A breaking change here can be hugely costly because of the accumulated time it takes to evaluate, fix and test each required change. In some cases the people that wrote the original code have moved on and nobody knows or understand what it does anymore. I see that daily (not the break, the lack of knowhow). Anyway, I don't think there much point in flogging this much more so I'll let you have the last word - I know you want it 🙂
  7. Anders Melander

    Check for override

    Ehem.. I think you should speak for yourself and not put these labels on the motives of other developers you know nothing about. Breaking backward compatibility is easy. Maintaining it is often very hard. I have seen many examples of projects that have stranded on old versions of 3rd party libraries because it was simply to costly to locate and fix breaking changes. That said I naturally agree that one should strive to move code forward and eliminate dependencies on backward compatibility.
  8. Anders Melander

    Check for override

    Are you saying that it wasn't worth it back when the change was made or that it isn't worth it anymore (i.e. today)? IMO the change was definitely worth it at the time because it didn't break backward compatibility and AFAIR didn't introduce new problems. They could have marked the old methods deprecated at some point and eventually retired it completely. AFAIK the change didn't introduce any new problems in older TStream descendants with 2+Gb files - it just made them possible going forward. If you have examples of bugs then I'd love to hear of them.
  9. Anders Melander

    Check for override

    Good thing you're not in charge of the RTL then. IRL backward compatibility matters.
  10. Anders Melander

    Check for override

    You're missing the point. The purpose was to provide backward compatibility for existing descendants of TStream - not existing code using TStream.
  11. Anders Melander

    Check for override

    ...or just see TStream.Seek(Longint, Word) in classes.pas.
  12. Anders Melander

    Trouble with (very) simple XML-parsing

    Why do you have this test? I would think that the second variant (LDocument.getElementsByTagName) would be good enough... I also think it would be safer if you used XPath or specified the path in your search criteria: LDocument.getElementsByTagName('/BkToCstmrStmt/Stmt/Acct/Id/IBAN');
  13. Anders Melander

    Right Process for Changing an Application's Icon?

    A word of warning to those (I'm counting 50 since yesterday) that downloaded this version: If your resources contains bitmaps that were created by older versions of Delphi (or rather applications built with older versions of Delphi) then the resource editor might corrupt them on save. It appears that a bug was introduced in TBitmap between Delphi 2009 and 10.2. Here's the short version: The format of a windows bitmap is basically 1) Header, 2) Color table, 3) Pixel data. For bitmaps with PixelFormat>pf8bit the color table is optional. The Header specifies the number of colors in the color table (the TBitmapInfoHeader.biClrUsed field). Older versions of Delphi sometimes saved bitmaps in pf24bit/pf32bit format with a color table and the corresponding value in the biClrUsed field. This was unnecessary but harmless and perfectly legal according to the bitmap specs. Here's an example of what such a bitmap might look like: [File header] [Bitmap header, biClrUsed=16, biBitCount=32] [Pixel data] These bitmaps can be read by newer versions of Delphi, but when the bitmaps are written again they become corrupt. Delphi keeps the value in the biClrUsed field but fails to write the corresponding color table. The result is that the pixel data ends up at the wrong file offset. Here's an example of a corrupt bitmap: [File header] [Bitmap header, biClrUsed=16, biBitCount=32] [Pixel data] The reason why this is a problem for the resource editor is that it is built with Delphi 10.2. I have a fix for the problem but I'm not ready to release a new version with the fix. Here's the fix btw: // Fix for bug in TBitmap. // Saving bitmap with PixelFormat>pf8bit with biClrUsed>0 fails to save the color table // leading to a corrupt bitmap. type TBitmapColorTableBugFixer = class helper for TBitmap type TBitmapImageCracker = class(TBitmapImage); public function FixColorTable: boolean; end; function TBitmapColorTableBugFixer.FixColorTable: boolean; begin if (TBitmapImageCracker(FImage).FDIB.dsBmih.biBitCount > 8) and (TBitmapImageCracker(FImage).FDIB.dsBmih.biClrUsed <> 0) then begin TBitmapImageCracker(FImage).FDIB.dsBmih.biClrUsed := 0; Result := True; end else Result := False; end; The problem appears to be the same one reported here: Setting TBitmap.PixelFormat can lead to later image corruption or EReadError
  14. Anders Melander

    Right Process for Changing an Application's Icon?

    Only because I've just uploaded a new version 🙂. It's been gone for at least 5 years. My ISP keeps flagging it as a virus (probably because it's built with Delphi) and taking it offline.
  15. Anders Melander

    Right Process for Changing an Application's Icon?

    It's my own. You can get it here: http://melander.dk/download/ResourceEditor20190309a.zip