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Everything posted by PeterBelow

  1. Timer messages have low priority. If your DoProcessMessages call takes longer than the message interval then a timer tick will not add a new wm_timer message to the queue but increment an internal count for the message already in the queue. Use a waitable timer and one of the MsgWait API functions instead of SetTimer,
  2. PeterBelow

    Resolve a uses clause unit path?

    Well, there is a FileSearch function in Sysutils that will search for a file in semicolon-separated list of directory names, but of course you still have to extract the library path from the IDE settings (= registry key, specific for an IDE version), the search path from the current project, if relevant, replace any macros ($(name)) in the pathes etc. to get the list of folders. I'm not aware of a ready-made function for this exposed in the RTL or Open Tools API.
  3. PeterBelow

    The Embarcadero GetIt server could not be reached...

  4. Yes, it is far from easy to switch processing to a specific secondary thread. Basically it is only possible savely if that thread has been written for this. So i can only concur with your previous reply: the responsibility of handling the synchronizing should fall to the code providing the callback.
  5. PeterBelow

    handling predicate conditions

    Yes, but the error you get then will not immediately indicate what the problem is. The way I do it its clear that the problem is a contract violation, and one can write unit tests that check whether the method correctly detects a contract violation.
  6. PeterBelow

    handling predicate conditions

    I usually test for pre and postconditions like this: procedure TBlobDB.CreateNewDatabase(aDBStream, aIndexStream: TStream; aTakeStreamOwnership: boolean); const Procname = 'TBlobDB.CreateNewDatabase'; begin if not Assigned(aDBStream) then raise EParameterCannotBeNil.Create(Procname,'aDBStream'); if not Assigned(aIndexStream) then raise EParameterCannotBeNil.Create(Procname,'aIndexStream'); This is for errors that are supposed to be found and fixed during the testing phase or (for library code) in unit tests. For user input the input is validated before it is used by the program, if this is at all feasable. The end user should never see an exception coming from parameter validation at a lower level, in my opinion, since the UI context may not be evident at that point and it may be unclear to the user what he did wrong.
  7. PeterBelow

    Debugging Inline Variables in 10.3.2

    Well, the cure is simple: do not use inline variables 😉. They are alien to the language anyway and serve no real purpose IMNSHO...
  8. Did you just open the old D7 project in Rio to start the migration? That is not a good idea for such a massive version jump. After you have extracted the complete old project from version control, close all files and the RIO IDE and go to the project folder on disk and move all files not having one of the following extensions to a zip folder: dpr, pas, res, rc, ico If the project contains other resources you may keep them as well. The important part is to delete the old project file (do not remember what extension it used in D7, perhaps bdsproj, and the old cfg file as well. Then open the IDE and open the project's dpr file. This will create a new project file. The project will show up in the project manager view and should have the Win32 target assigned automatically. It will also have a default build configuration assigned, but the settings used for that will not all be suitable for your project. So the next step is to open the project options dialog (from the Project menu or the project manager view's context menu) and adjust the settings, especially the search and output pathes. Beware! The settings dialog is completely different from the one you may know from D7! Since you can have multiple build configurations for multiple target platforms the settings are organized as a kind of hierarchy, and you have to first select the correct hierarchy level for the settings you want to modify. You do this using the combo box at the top of the right-side pane, pick "32 bit windows platform" under "all configurations". In the left-hand treeview you should have the top node (Delphi compiler) selected, that shows the page with the project-specific path settings on the right. The most important things here to get your project to compile are the unit scope names and the search path. Delphi uses namespace-like scope names on the run-time and framework units and has done so since many versions. But D7 did not use unit scope names. To make migration easier the IDE and the compiler will automatically search for units named in Uses clauses within the scopes listed in the unit scope names field if the unit is not found by the given name (the System scope is always searched, though). The default list contains the most frequently used scopes, but you have to make sure that VCL and VCL.Win are in the list as well. The search path becomes important if your project uses custom units not located in the project folder (where the dpr file and the generated dproj file reside). You have to add all pathes for units there that are not found on the IDE library path (as dcu or pas). I don't know how you organize your project files on disk. I usually use something like projectname (dpr, dproj, cfg) source (pas, inc) bin (dcus) exe (exe) doc (documentation) resources (rc and res files, files embedded in them) test (unit tests and other test programs) So the output folder path set in the dialog would be (without the quotes, of course) ".\exe". The unit output path would be ".\bin\$(platform)\$(config)" The search path would be ".\bin\$(platform)\$(config);.\source;$(common);$(include)" "common" and "include" are environment variables defined in the IDE Options dialog that contain the pathes to my code library (not project specific units). The resource compiler node on the left also has a search path setting, these are for rc and res files, but in my experience this has been a bit unreliable in recent versions; i often have to add rc files explicitely to a project to get them compiled and linked in.
  9. PeterBelow

    Playing multiple wave files simultaneously

    As far as I remember from older discussions you have to merge (mix) the sound files into one before you can play it. Windows has an API for that, see Audio mixers If you google for mixer audio sound delphi you may find something useful.
  10. PeterBelow

    Debugging Inline Variables in 10.3.2

    Mh, not very enlightening. Looks like setting up a exception handling frame.
  11. PeterBelow

    Debugging Inline Variables in 10.3.2

    I'm surprised that you can even set a breakpoint on a variable declaration. Makes no sense in my opinion. Could you please run to the breakpoint and switch to the CPU disassembly view to see what statement the breakpoint is actually on? I have not been able to install 10.3.2 myself yet due to trouble with the licence, so cannot test that myself.
  12. PeterBelow

    Component Compatibility 10.3.2 vs. 10.3.1?

    Generally the minor releases of Delphi (e.g. 10.3.1 10.3.2) are binary compatible, which means there are no changes to the interface part of run-time library or frame work units, so dcus and packages build for one release can be used with other. The same applies to the open tools API, so components you bought for 10.3.1 should work in 10.3.2, even if you cannot recompile them since you don't have the source. This only applies if said components play by the rules, of course. If they rely on undocumented features or dig around in the IDE's innards all bets are off.
  13. PeterBelow

    VCL component issue

    Is the project perhaps Win64 or FMX?
  14. PeterBelow

    WinAPI to query if a form is ready to Rock.

    Some of the form properties (e.g. border and bordericons) are implemented via window styles on the API level, and Windows only honors some of the styles when the window is first created. Changes to these properties recreate the window handle for this reason. Another reason are modal forms with popupmode pmauto or pmexplicit; their window handle has to be recreated when they are shown to tie them to their popup parent in Z-order. Changing the formstyle also recreates the handle.
  15. PeterBelow

    WinAPI to query if a form is ready to Rock.

    There is no panacea for this kind of problem, too much depends on how the form in question has been set up. What you can do from "outside" the process is check if the window is visible (IsWindowVisible) check whether it is the current foreground window (GetForegroundWindow) check whether its message loop is running (WaitForInputIdle, or use SendMessageTimeout to send a do-nothing message to the form, e.g. wm_null, the call will not return until the loop is running) Nothing will help you if the form does some kind of delayed initialization, e.g. using a timer started when the form is created. Also keep in mind that a Delphi form may recreate its window handle at the drop of a (virtual) hat during the initialization phase.
  16. PeterBelow

    E2161 Warning: Duplicate resource

    The <projectname>.res file is the one the IDE builds for the form resources, it also contains versioninfo if you enabled that in the project options. The verinfo.res has to be something you added yourself to the project, or some add-in you use added. Look for a {$R verinfo.rc verinfo.res} line in the project dpr file and delete it. The confllict arises since both resources have the same ID.
  17. PeterBelow

    Refer to Form Control without using the Form unit?

    You cannot do it this way without using the form units. It is not a good way to translate an application anyway. Have you looked at the IDE Translation Manager?
  18. PeterBelow

    Delphi not responding to errors..

    You can tell the debugger to ignore certain types of exceptions, this is offered as a button on the exception dialog you get when the IDE debugger catches an exception. Perhaps you did this by accident. Call up the Tools --> Options dialog,on the left scroll down to the end of the list. There you find a "debugger options" node with two subnodes for language and OS exceptions. The associated pages list the exception types to ignore; you can reactivate them there as well. see the attached dcreenshot, unfortunately from a german IDE.
  19. PeterBelow

    Cannot login to Quality Central - who to contact?

    Can you get to members.embarcadero.com and log in there with your EDN account?
  20. PeterBelow

    Best practices for system migration?

    You only need the licence key, which you can copy from the Licence manager via clipboard.
  21. PeterBelow

    Bad build a mystery

    Did you check the dpr file for bad line ends (only cr or only lf)? What happend to me some time ago was that the IDE inserted a new form unit name in the DPR file smack in the middle of an existing one, which of course did not build anymore and resulted in some weird error messages (no IDE crash, though). I found out that the file had become corrupted, with mix of linebreak styles. I never found out how that happended...
  22. PeterBelow

    Database connection as parameter in class creation

    For 1: If you like to set up the connection at design-time in a datamodule the approach is OK, and you do not need to pass the connection object as a Var parameter. Objects are reference types, so you pass a reference to the connection object, and that can even be done as const, since you can work with the object's properties or pass the reference on this way as well. Just do not free the connection object in the "record class", it belongs to the datamodule and will be freed by it when the datamodule is destroyed. For 2: "Best" is hard to define in this context. For a complete separation of the UI from the data it works with you need a bit more than just keeping connection and query/table objects out of the forms/frames and business logic code out of event handlers there. But writing a model-view-presenter framework or a full-blown object-relational mapper (ORM) framework from scratch is a lot of work. For smaller projects it may not pay to go to these length, especially if you only aim for one platform with a desktop client.
  23. Using threads to do thing in parallel obviously only works efficiently if the "things" do not depend on each other. As soon as a thread has to wait on the results of another the processing slows down and the chance of deadlocks goes up. Also, using more threads than the hardware has cores/cpus quickly gets you to a point of diminishing returns, since the OS has some administrative overhead to manage the threads. So, don't overdo it, especially in a scenario like a parallel for loop, where the code can only continue after the loop has finished completely it may be more efficient to split the loop into several and run each in its own thread. If the loop does not have that many iterations and executes each round fairly quickly setting up the individual tasks in a parallel for may consume more time than you gain by doing stuff in parallel. There is no substitute for thorough testing and timing in such a scenario.
  24. No, you can operate on several canvases (of offline bitmaps or metafiles) in parallel, its is just a little bit less efficient since each canvas has to create its own font, pen, brush instead of using an existing one from the VCL sharing pool.
  25. If you work with a TCanvas in background threads always wrap your code in canvas.lock; try ...operate on canvas here finally canvas.unlock; end; The VCL has a build-in mechanism to optimize use of GDI objects, which is shared between all TCanvases used, and his mechanism is not thread-safe. Locking the canvas makes sure it does not use this mechanism while it is locked.