

Brian Evans
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Everything posted by Brian Evans
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IBX is Crashing Application on Windows XP / Server 2003
Brian Evans replied to MikeMon's topic in Databases
Can check what API calls are being made and if some are failing shortly before the application gives up the ghost. One tool for that is API Monitor by Rohitab Batra http://www.rohitab.com/apimonitor -
Is there a way to -detect- that the VCL has been accessed from outside of the main thread?
Brian Evans replied to Der schöne Günther's topic in RTL and Delphi Object Pascal
Note you can access the VCL from another thread in a thread-safe manner using Synchronize (https://docwiki.embarcadero.com/Libraries/Athens/en/System.Classes.TThread.Synchronize) Code inside the Synchronize is run using the main thread. -
function declarations without ; at the end
Brian Evans replied to Günther Schoch's topic in RTL and Delphi Object Pascal
In the full IDE more than just the compiler parses the code and some of the other parsers have been slow, flaky and unreliable for a long time. I don't think allowing and including code like this is helping any. -
Can the UI be updated in any way while the main thread is doing work ?
Brian Evans replied to dormky's topic in VCL
This seems like adding requirements covering corner cases or minutiae that are unlikely to be meaningful to actual users. Most just dislike doubt and uncertainty - is it still doing anything? did it freeze? How much longer will it take? - provide some indication that answers those questions and most users will be happy. Trying for a precise UI treatment while also not fixing threading in the main application seems like a way to waste a lot of time on a secondary issue - just get the information displayed. -
Can the UI be updated in any way while the main thread is doing work ?
Brian Evans replied to dormky's topic in VCL
One option: Create another application that shows a loading GIF and occasionally send it messages from your main thread to update/exit/etc. Has drawbacks but disturbs the exiting application the least code and UI wise. -
Two of the big ones - Microsoft SQL Server and Oracle - still provide and support 32-bit clients. The databases with per server and/or per client license fees have more resources and incentives to keep that support going.
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An elapsed time clock is another option. If the time taken has some predictability users tend to like this option - over time they get a feel for how long some tasks take and if they can grab a quick coffee etc. In the Delphi 7 days I used a component from the Developer Express Forum Library for this but they stopped maintaining it a long time ago.
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There is a 32 bit ODBC driver, currently it is: Connector/ODBC 8.0.40. (select version 8.0.x in the list here: https://dev.mysql.com/downloads/connector/odbc/ ) It does mean using the FireDac ODBC driver to then use the MySQL ODBC driver vs going more directly.
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How to NOT save changes when compiling?
Brian Evans replied to Squall_FF8's topic in Delphi IDE and APIs
Note "IDE Insight", a search box on the right of the title IDE Window's title bar can be used to search for settings. Once you remember it exists finding settings is usually much faster than manually going through the settings dialogs. -
FMX app hanging at start after windows 11 run for a long time(a few hours).
Brian Evans replied to wqmeng's topic in General Help
Could be some piece of software or the display driver. Hard to say without more details of the system. The contents of the Display tab of dxdiag might help. Also check for any tray icons or software running in the background with % GPU (CTRL-SHIFT-ESC, Processes, right click column headers and turn on GPU engine column). -
FMX app hanging at start after windows 11 run for a long time(a few hours).
Brian Evans replied to wqmeng's topic in General Help
How about fully logging/signing out then back in (so it resets the Window session)? Very odd such basic functionality is failing. -
FMX app hanging at start after windows 11 run for a long time(a few hours).
Brian Evans replied to wqmeng's topic in General Help
Instead of rebooting try Win+Ctrl+Shift+B shortcut to reset/restart the graphics driver. Not a solution but might point to what is causing problems. -
Outside of the recently (relatively anyway) introduced STRICT tables the type of a column is really just a suggestion and it will happily stick a string anywhere if asked. Most tools try to tame this by enforcing the type but don't always succeed. SQLite website: 1. Datatypes In SQLite Most SQL database engines (every SQL database engine other than SQLite, as far as we know) uses static, rigid typing. With static typing, the datatype of a value is determined by its container - the particular column in which the value is stored. SQLite uses a more general dynamic type system. In SQLite, the datatype of a value is associated with the value itself, not with its container. The dynamic type system of SQLite is backwards compatible with the more common static type systems of other database engines in the sense that SQL statements that work on statically typed databases work the same way in SQLite. However, the dynamic typing in SQLite allows it to do things which are not possible in traditional rigidly typed databases. Flexible typing is a feature of SQLite, not a bug. Update: As of version 3.37.0 (2021-11-27), SQLite provides STRICT tables that do rigid type enforcement, for developers who prefer that kind of thing.
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The type-less nature of SQLite makes it not ideal for data in transit between databases. You end up doing work for edge cases that a typed database would handle on it's own. Want real fun? Have both English and French users, like in Canada with it's two official languages, where the decimal separator is period and comma respectively. Soon as strings start appearing in a column storing transaction values the fun begins. It can work as long as you listen to Egon Spengler and never cross the streams. Soon as you do however ...... think an online store that occasionally gives out 99.9% discounts level bad (few would complete the reverse - an order with items having a 1000x price increase except maybe the government).
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FMX app hanging at start after windows 11 run for a long time(a few hours).
Brian Evans replied to wqmeng's topic in General Help
No solution but some thoughts. FMX forms use GPU resources including when designing in the IDE which is not the case for most VCL forms/components. Perhaps re-install / upgrade to the latest graphics drivers with whatever 'clean install' option is available selected in the installer. -
As well a lot of controls with lists have a BeginUpdate and EndUpdate so you can stop visually updating the control for every change to an item. Wrap things in an Try/Finally to make sure EndUpdate is always called. lv1.items.BeginUpdate; try // add multiple items finally lv1.items.EndUpdate; end; From the help for Vcl.ComCtrls.TListItems.BeginUpdate : Prevents updating of the list view until the EndUpdate method is called. Call BeginUpdate before making multiple changes to the list of items. When all changes are complete, call EndUpdate so that the changes can be reflected on screen. BeginUpdate and EndUpdate prevent excessive redraws and speed processing time when new items are added, deleted, or inserted.
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- delphi xe7
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As Remy already mentioned an array or list works. I tend to put such things in a dynamic array. Can move the array to someplace higher in scope if desired but for code that doesn't run that often I usually create it as needed and let it fall out of scope and be destroyed. procedure TForm1.Button1Click(Sender: TObject); Var SomeMemos : array of TMemo; begin SomeMemos := [Form1.Memo1,Form1.Memo2,Form1.Memo3,Form1.Memo4,Form1.Memo5]; // Dynamic Arrays are zero based so need to subtract one compared to 1 based SomeMemos[5 -1].Lines.Add('test!'); end;
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Is TBitmap.LoadFromStream blocking when used in a BG thread?
Brian Evans replied to domus's topic in FMX
In general an ever growing queue is a bad thing - at some point adding new items has to at least pause or it grows unbounded. The default size in the .create is a bit on the low side at 10 which I think is a source of bugs. This parameter perhaps should not have a default forcing the developer to think of a sane value or the need to .grow(). The defaults for create(): AQueueDepth is the length of the queue, which is by default set to 10. PushTimeout is the timeout when a new element is pushed, which is by default set to INFINITE. PopTimeout is the timeout when a new element is popped, which is by default set to INFINITE. -
Strange behavior with "RANGE checking" and "Overflow checking"
Brian Evans replied to DelphiUdIT's topic in RTL and Delphi Object Pascal
Sure you don't have the options reversed between debug/release? The processor might be making poor choices in where it sends instructions but it would be odd to see a couple more instructions execute faster even with poor choice of execution unit scheduling or register usage. The only difference I see is the default debug settings generate code that does range bounds checking on a[i] checking it is within the array bounds. -- range and bounds checking off Project1.dpr.51: DivandMod(a[i], 2039, resto); 000000000036CB5E 488B05834B0300 mov rax,[rel $00034b83] 000000000036CB65 8B0D594B0300 mov ecx,[rel $00034b59] 000000000036CB6B 8B0C88 mov ecx,[rax+rcx*4] 000000000036CB6E BAF7070000 mov edx,$000007f7 000000000036CB73 4C8D05764B0300 lea r8,[rel $00034b76] 000000000036CB7A E881FEFFFF call DivandMod -- range and bounds checking on Project1.dpr.51: DivandMod(a[i], 2039, resto); 000000000036CB83 8B053B4B0300 mov eax,[rel $00034b3b] 000000000036CB89 48833D574B030000 cmp qword ptr [rel $00034b57],$00 000000000036CB91 740D jz Project1 + $150 000000000036CB93 488B0D4E4B0300 mov rcx,[rel $00034b4e] 000000000036CB9A 483B41F8 cmp rax,[rcx-$08] 000000000036CB9E 7205 jb Project1 + $155 000000000036CBA0 E8BBFFECFF call @BoundErr 000000000036CBA5 488B0D3C4B0300 mov rcx,[rel $00034b3c] 000000000036CBAC 8B0C81 mov ecx,[rcx+rax*4] 000000000036CBAF BAF7070000 mov edx,$000007f7 000000000036CBB4 4C8D05354B0300 lea r8,[rel $00034b35] 000000000036CBBB E840FEFFFF call DivandMod -
Check whatever component/library you are using to add export to xlsx capability to QuickReport. Update: Seems they added it at some point.
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Does "Size to grid" actually do something?
Brian Evans replied to dummzeuch's topic in Delphi IDE and APIs
Seems busted, does nothing here in VCL. Help says it: Changes the position and the size of the selected control so that every edge is aligned with its closest line of the design grid. Help text from toolbar descriptions here: https://docwiki.embarcadero.com/RADStudio/Athens/en/Toolbars -
The Snipping Tool in Windows 11 does video in addition to static screen grabs. After triggering (SHIFT+Win+S) make sure video is selected, select the screen region you want to record then start recording.
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Delphi IDE and application created crashes with Mouse click on TActionMainMenuBar
Brian Evans replied to srikanthch's topic in VCL
Isn't SPHTMLHelp an ancient third-party library? If I remember it added support for opening CHM help files before Delphi itself did over a decade ago. -
It can generate a text file per exception that contains much more than just the stack trace. You can then do whatever you want with the text file. The log viewer tool they provide can display the contents of that text file in an easy-to-read way - nicely formatted and split up. ref: https://www.eurekalog.com/help/eurekalog/bug_report_page.php
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Could just be logging the stacks of exceptions that are handled and logging them as part of seeing what errors users hit most often. Of limited use but have seen it done - like graying out invalid choices + hint of why on mouse over or click instead of letting the user select an item and then producing an error dialog/message latter on that users are hitting far too often.