We're migrating our XE projects to XE5, however, we encountered the access violation exception about teechart during the test.
I've created a test application to recreate the issue. With the test app, it works fine when open the first teechart form but will get the access violation exception when open it second time or open a new form.
Please refer to the attached test app from the following QC (embarcadero).
http://qc.embarcadero.com/wc/qcmain.aspx?d=122729
When debug it with DCUs. The exception happened when notifying TDBChart's OnStateChange event.
procedure TDataSet.DataEvent(Event: TDataEvent; Info: NativeInt);
begin
...
if NotifyDataSources then
begin
for I := 0 to FDataSources.Count - 1 do
FDataSources[I].DataEvent(Event, Info); // <<---- Access Violation
if FDesigner <> nil then FDesigner.DataEvent(Event, Info);
end;
end;
As David Berneda said at Quality Central:
Its related to using an internal TObjectList generic collection inside
DBChart. The code has been improved so the error is fixed now (a new
code takes care of destroying the ObjectList items correctly).
As a workaround, you can add this code at your form's OnClose event:
type
TChartAccess=class(TDBChart);
procedure TOutcomesGraphFm.bbtnCloseClick(Sender: TObject);
begin
TChartAccess(dbcBar).RemovedDataSource(bsTestScores,bsTestScores.DataSource);
Close;
end;
Related
In my application I want to copy all the text from a website into a string variable. Because of some issues with Indy, I want to use the webbrowser component.
The following code works perfectly for me:
procedure TForm1.Button1Click(Sender: TObject);
begin
WebBrowser1.Navigate('www.tribalwars.nl');
while WebBrowser1.Busy do
Application.ProcessMessages;
Memo1.Lines.Add((WebBrowser1.Document as IHTMLDocument2).body.innerText);
end;
However, in the example above I use a WebBrowser that has been manually created on my Form1.
Now I want to create it during runtime. I tried the following code:
procedure TForm1.Button2Click(Sender: TObject);
var Web: TWebBrowser;
begin
Web := TWebBrowser.Create(nil);
Web.Navigate('www.tribalwars.nl');
while Web.Busy do
Application.ProcessMessages;
Memo1.Lines.Add((Web.Document as IHTMLDocument2).body.innerText); //This line raises the error mentioned below
Web.Free;
end;
Unfortunately it keeps raising the following error:
Project Project1.exe raised exception class $C0000005 with message 'access violation at 0x005d9b4f: read of address 0x00000000'.
I guess I'm trying to use something that hasn't been created yet, or somewhere in that direction.
I hope someone can help me get this to work!
EDIT: whosrdaddy mentioned that I should make this component visible. How can I do that? I tried this, but it doesn't work:
procedure TForm1.Button2Click(Sender: TObject);
var Web: TWebBrowser;
begin
Web := TWebBrowser.Create(nil);
Web.Left := 50;
Web.Top := 50;
Web.Width := 50;
Web.Height := 50;
Web.Visible := True;
Application.ProcessMessages;
Web.Navigate('www.tribalwars.nl');
while Web.Busy do
Application.ProcessMessages;
Memo1.Lines.Add((Web.Document as IHTMLDocument2).body.innerText);
Web.Free;
end;
The problem is that when you create TWebBrowser dynamically and pass NIL as the owner, unfortunately the parent is also NIL. a non -NIL parent is needed to display anything.
Normally you would do this:
var
pnlBrowser : TPanel;
Web : TWebBrowser;
Web := TWebBrowser.Create(nil);
Web.Parent := pnlBrowser;
BUT, unfortunately, you cannot (directly) do this either (you get an error message "read-only property" if you try).
But luckily, there IS a way to circumvent the problem:
TWinControl(Web).Parent := pnlBrowser; // this works OK!
I have no idea WHY the parent property of the TWebBrowser class is read-only.
Reading the Delphi documentation, also
TControl(Web).Parent := pnlBrowser; // this should also work
as a side note:
If you have TmsMediaPlayer component (the ActiveX version of Microsoft Windows Media Player), setting parent using the Delphi's Parent property will stop any video playing, but setting it directly through a windows API call does not.
IF you want to use your TWebBrowser to play videos, changing the Parent property on the fly may also stop any video playing. If so it is worth trying to change the parent using windows API call directly instead to avoid stopping a video playing in the web browser.
1) try to change Your TWebBrowser component to TEmbeddedWB
- the parameters/events are the same + lots of extras You can use...
2) I think the problem is with the readystate of your created browser after navigation - its not loaded completely (+maybe it has not assigned parent)
try use the following code (replace Your TWebBrowser component name):
Web.Navigate('www.tribalwars.nl')
repeat application.processmessages; until web.readystate=4;
Memo1.Lines.Add((Web.Document as IHTMLDocument2).body.innerText);
Experts, take the following code snippet below:
var
aAllTasks : Array [0..1] of ITask //global private var
Procedure SetImage();
begin
//..
//.. Get a URL of an image stored on a server
//..
aAllTasks[0] := TTask.Run(
Procedure
begin
// Download the Image and display the image
end);
aAllTasks[1] := TTask.Run(
Procedure
begin
// Get the rating of the image from a REST server
end);
end;
when the debugger hits
aAllTasks[1] := TTask.Run(...);
I get
First chance exception at $001A30B5. Exception class EThreadNameException with message ''. Process APPNAME (126391)
It throws the exception but it does not seem to crash the App
This only happens when debugging/running iOS apps
iOS 9.2
RS 10 Seattle (with Update 1)
PA server 17.0 (with hotfix.. V 8.0.1.52)
Xcode version 7.2 (7C68)
What would cause this and how would I fix it?
Your code calls, TThread.NameThreadForDebugging. That looks like this:
class procedure TThread.NameThreadForDebugging(AThreadName: string; AThreadID: TThreadID);
{$IF Defined(MSWINDOWS)}
.... // windows specific code removed
{$ELSE MSWINDOWS}
const
cExceptionMessage = 'Type=$1000,Name=%s,ThreadID=%d,Flags=0';
EMBDBKPRESENTNAME = 'EMB_DBK_PRESENT';
{$IF Defined(MACOS)}
OLDEMBDBKPRESENTNAME = 'EMB_MACOSX_DBK_PRESENT';
{$ENDIF}
begin
{$IF Defined(MACOS)}
if (getenv(EMBDBKPRESENTNAME) <> nil) or (getenv(OLDEMBDBKPRESENTNAME) <> nil) then
{$ELSEIF Defined(ANDROID)}
if (System.DebugHook <> 0) or (getenv(EMBDBKPRESENTNAME) <> nil) then
{$ELSE}
if (getenv(EMBDBKPRESENTNAME) <> nil) then
{$ENDIF}
begin
try
raise EThreadNameException.Create(
Format(cExceptionMessage, [AThreadName, AThreadID]));
except
end;
end;
end;
{$ENDIF !MSWINDOWS}
This function is called when you wish to give your thread a name. Now, thread objects do not have names. So when you give your thread a name, it is for debugging purposes only. The debugger keeps track of the names you provide, and associates them with thread IDs. Then when the debugger presents information about threads, it can look up the name from the ID and present that to you. But this is purely a debugger mechanism because the operating system does not support thread names.
So, how do you signal to the debugger that you wish to give a thread a name. Well, you throw a specific exception. The debugger is aware of the exception and gets the first chance to handle the exception. The debugger receives the name and the thread ID in the exception text and makes a note of that information.
Notice that the exception is swallowed immediately and so this does not interrupt the flow of the program.
So, it is normal for this exception to be raised, to be handled by the debugger, and not to impact on the behaviour of the program. What is odd is that the debugger is breaking on that exception. I would have expected that exception to be ignored by the debugger, by default.
An old QC report (QC#105310) for OSX describes exactly the behaviour that you are observing. That issue was closed and marked as fixed in XE7. Perhaps this issue has re-surfaced, or perhaps it was never fixed for the mobile platforms. I suggest that you submit a bug report to Quality Portal.
In my project, i'm trying to connect one more UNIT, named Lang_Unit.pas with some classes and procedures, but, while compiling the Project, Delphi gives unknown error called "[dcc32 Fatal Error] Lang_Unit.pas(5): F2084 Internal Error: AV07953449-R26D7474C-0".
And the point is that, what if i will close my project, or remove this connected UNIT, error is not getting away.
And if i will create clear default VCL Application, its still gives this error.
And only when i'm restarting my Delphi 2010, error is getting away.
But, if i will try to edit something in the code, this error is comes again...
What is problem ? Everything was works fine, im not touched nothing.
I've just turned off my PC, then after some time turned it ON and opened my Project and edited my code, then i see this error...
If Its will help, here is my Lang_Unit.pas code :
unit Languages_UNIT;
interface
Uses
System.Generics.Collections, IniFiles;
Type
TLanguages_List = Class
private
LangType:string;
LangDescription:string;
LangFile:TIniFile;
public
Constructor Create(LType,LDes:string; LFile:TiniFile);
Function GetLangType:string;
Function GetDescription:string;
Function GetStructure:TIniFile;
End;
TLanguages_Controller = Class
public
Function GetStructureByType(RequestedType:string; LangList:TObjectList<TLanguages_List>):TIniFile;
Function TypeExists(RequestedType:string; LangList:TObjectList<TLanguages_List>):Boolean;
Procedure LoadLanguage(RequestedType:string; LangList:TObjectList<TLanguages_List>);
End;
implementation
uses Unit1;
Constructor TLanguages_List.Create(LType,LDes:string; LFile:TiniFile);
Begin
LangType:=LType;
LangDescription:=LDes;
LangFile:=LFile;
End;
Function TLanguages_List.GetLangType:string;
Begin
Result:=LangType;
End;
Function TLanguages_List.GetDescription:string;
Begin
Result:=LangDescription;
End;
Function TLanguages_List.GetStructure:TIniFile;
Begin
Result:=LangFile;
End;
Function TLanguages_Controller.GetStructureByType(RequestedType:string; LangList:TObjectList<TLanguages_List>):TIniFile;
var
i:integer;
Begin
For i := 0 to LangList.Count-1 Do
Begin
IF(LangList[i].GetLangType=RequestedType) Then
Begin
Result:=LangList[i].GetStructure;
Break;
End;
End;
End;
Function TLanguages_Controller.TypeExists(RequestedType:string; LangList:TObjectList<TLanguages_List>):Boolean;
var
i:integer;
GOTYA:Boolean;
Begin
GOTYA:=False;
For i := 0 to LangList.Count-1 Do
Begin
IF(LangList[i].GetLangType=RequestedType) Then
Begin
GOTYA:=True;
Break;
End;
End;
IF(GOTYA) Then
Result:=True
Else
Result:=False;
End;
Procedure TLanguages_Controller.LoadLanguage(RequestedType:string; LangList:TObjectList<TLanguages_List>);
var
i:integer;
SLS:TIniFile;//SELECTED LANGUAGE STRUCTURE
CS:string;//CURRENT SECTION
Begin
//GET SELECTED LANGUAGE STRUCTURE
For i := 0 to LangList.Count-1 Do
Begin
IF(LangList[i].GetLangType=RequestedType) Then
Begin
SLS:=LangList[i].GetStructure;
Break;
End;
End;
//START LOADING SELECTED LANGUAGE
//TABS SECTION LOAD
CS:='TABS';
SD_DEFNAME:=SLS.ReadString(CS,'Speed_Dials','Speed_Dials');
Form1.goleft.Hint:=SLS.ReadString(CS,'Back','Back');
Form1.goright.Hint:=SLS.ReadString(CS,'Forward','Forward');
REFLESHBTN_TEXT:=SLS.ReadString(CS,'Reflesh','Reflesh');
STOPBTN_TEXT:=SLS.ReadString(CS,'Stop','Stop');
//PAGE_POPUP SECTION LOAD
CS:='PAGE_POPUP';
Form1.ChromiumPopup.Items[0].Caption:=SLS.ReadString(CS,'Forward','Forward');
Form1.ChromiumPopup.Items[1].Caption:=SLS.ReadString(CS,'Back','Back');
Form1.ChromiumPopup.Items[2].Caption:=SLS.ReadString(CS,'Reflesh','Reflesh');
Form1.ChromiumPopup.Items[3].Caption:=SLS.ReadString(CS,'Copy_Link','Copy Link');
Form1.ChromiumPopup.Items[4].Caption:=SLS.ReadString(CS,'Save','Save');
Form1.ChromiumPopup.Items[5].Caption:=SLS.ReadString(CS,'Print','Print');
Form1.ChromiumPopup.Items[6].Caption:=SLS.ReadString(CS,'view_source','View Source');
Form1.ChromiumPopup.Items[7].Caption:=SLS.ReadString(CS,'code_debug','Code Debug');
End;
end.
Internal error means that the compiler itself is in a 'confused' state.
The way to get out of this is to:
Save your code in a safe location for later reference.
Restart Delphi
Revert the source code to the last known good state by undoing your last edits, or by loading a temp save file.
You can find the previous files in the _backup folder.
Make sure to set file type to any file.
In order to have Delphi generate a save file upon compilation you need to enable autosave
It's a good idea to have Delphi keep more than the default 10 saves. I like to set it to the max: 90.
Just keep restarting Delphi, and compile a previous version, until the internal error goes away.
Then you just recreate the code in a slightly different manner.
(You did save the original code right?)
I also had this problem (in Delphi 10 Berlin). It started shortly after I changed the name of a component in a frame. It also seemed very persistent. However I found the by right clicking the project and selecting 'Clean' followed by 'Build' solved the problem.
I had this issue with my system drive's memory less than 300mb left. It was especially choking in the cache folder. Prior to this error I had a sensible error (fatal error DBG) when I was attempting to recurse already async functions into a larger async function in a big multi threaded application. The compiler just gave up!(perhaps for circular references and too many subfunctions of a function) The two errors may not be related. But after freeing the system drive to about 2 Gigs upon restart and correcting the above mistake, I did a clean then it compiled just fine.
In my case, the solution for the F2084 error code was to change the encoding from ANSI to UTF8.
In my case, I made several packages that related one to another, and all were built as design and run time packages. But one day, I changed some of them to run-time only packages. After that I experienced this kind of error. It took me hours to realize that I should rebuilt all other related packages. After doing that, the error was away eventually.
i have given a chance to my software user to select dll from openfile dialog.(so my user can download dlls form my website and use it with the main project ). everything is working fine and it can even find that dlls is provided by me or selected an invalid dll.but the problem raises if the user selects a renamed file(eg : apple.txt file renamed to apple.dll ). i typed the code like this
try
dllHandle := LoadLibrary( pwidechar(openfiledialog1.filename)) ;
catch
{ showmessage if it is not a dll (but it can be any dll, it checks this is my dll or 3rd party later )}
end;
error message shown by delphi is 'bad library image selected'
but try catch is not working if the user selects invalid dll it is showing its own error message and struck up.
can anyone help me,i am using delphi 2009
There's no exception to catch because an exception is not raised when LoadLibrary fails; it just returns '0'.
You should check if 'dllHandle' is 0 or not, if it is, show the error information to the user by using GetLastError as documented. Alternatively you can use the Win32Check function in the RTL which will raise an exception with the appropriate error message:
(edit: Documentation of 'LoadLibrary' states that: To enable or disable error messages displayed by the loader during DLL loads, use the SetErrorMode function. So if you don't want the OS to show an additional dialog you'd set the error mode before calling LoadLibrary.)
var
dllHandle: HMODULE;
ErrorMode: UINT;
begin
if OpenDialog1.Execute then begin
ErrorMode := SetErrorMode(SEM_FAILCRITICALERRORS); // disable OS error messages
try
dllHandle := LoadLibrary(PChar(OpenDialog1.FileName));
finally
SetErrorMode(ErrorMode);
end;
if Win32Check(Bool(dllHandle)) then begin // exception raised if false
// use the libary
end;
end;
end;
On my form I have a IWTreeView and two buttons. One button deletes some IWTreeViewItems, the other releases the form:
procedure TIWForm1.IWButton1Click(Sender: TObject);
begin
IWTreeView1.Items[0].Subitems.Clear;
end;
procedure TIWForm1.IWButton2Click(Sender: TObject);
begin
Release;
end;
Releasing the form after deleting the IWTreeViewItems causes an exception:
Error message raised by the
application: Access violation at
address 004E0D8A in module
'TryTree.exe'. Read of address
00000000
When there is another form active and the application is not terminated by this form release, the error message is:
Error message raised by the
application: List index out of
bounds (-1)
Using IntraWeb 9.0.42 (because of TMS controls and Delphi 2006, as TMS has not tested with 10.0.17 and delphi 2006).
I tried to IWTreeView1.ClearAll in the form destroy, which did not help at all.
Instead of SubItems.Clear I now use
for i := IWTreeView1.Items[0].SubItems.Count-1 downto 0 do begin
TIWTreeViewItem(IWTreeView1.Items[0].SubItems[i]).Free;
end;
This works. Still open for better solutions, maybe not involving a loop through all subitems.