threads and gui - how to?

[phenixa]

hi,
i am new to c++ (used to program in java and c#)
for several days i have been trying to change gui from a thread,
i searched all the internet but couldnt find anything related,
i am using Borland c++ builder 6,

here is my code
hope
you ll find a solution

DWORD WINAPI TForm1::m_check(LPVOID param)
{
        DWORD status;
        HANDLE m_con[2];
        m_con[0] = report;
        m_con[1] = hExitEvent;
        while(true)
        {
                status = WaitForMultipleObjects(2,m_con,FALSE,INFINITE);
                Sleep(10); //do not use processor 100%
                switch(status)
                {
                        case WAIT_OBJECT_0:
                        Form1->write(message);
                        break;
                        case WAIT_OBJECT_0 +1:
                        return NULL;//exit

                        case WAIT_FAILED:
                        Form1->write("wait failed");
                        break;
                        default:
                        Form1->write("fail");
                        break;
                }



        }
}

this part is called by a thread when a button is clicked and runs
until exitevent is set
;

void TForm1::write(AnsiString inp)
{
      Edit1->Text += inp+"\n";
}

and code to modify gui
this all code doesnt gives an error but it doesnt changes anything on gui

when i put a break point on
Edit->Text
as i see text is changed but it doesnt appears at gui

[Percey]

I'm a pretty bad C++ programmer (where pretty = horribly) but I know in visual basic there's a property called CheckForIllegalCrossThreadCalls (there's a mouthful), that you can set to true/false, I'm pretty sure the code would be frowned upon, but I have used it before.

You could try that if you are using MVC++...

[Elysia]

Originally Posted by Percey

...but I know in visual basic there's a property called CheckForIllegalCrossThreadCalls (there's a mouthful), that you can set to true/false...

No such thing in C++.

You could try that if you are using MVC++...

Problem is that the OP is using Borland stuff, which is Borland only and will not work with other compilers.
(And I assume the poor amount of replies is also related to the fact that the OP uses Borland.)

[m37h0d]

try:

void TForm1::setText(AnsiString inp)
{
    TForm1::editText = inp;
}

void TForm1::write()
{
    Edit1->Text = editText;
}

DWORD WINAPI TForm1::m_check(LPVOID param)
{
        DWORD status;
        HANDLE m_con[2];
        m_con[0] = report;
        m_con[1] = hExitEvent;
        while(true)
        {
                status = WaitForMultipleObjects(2,m_con,FALSE,INFINITE);
                Sleep(10); //do not use processor 100%
                switch(status)
                {
                        case WAIT_OBJECT_0:
                        Form1->setText(message);                        
                        Synchronize(Form1->write);
                        break;
                        case WAIT_OBJECT_0 +1:
                        return NULL;//exit

                        case WAIT_FAILED:
                        Form1->setText("wait failed");
                        Synchronize(Form1->write);
                        break;
                        default:
                        Form1->setText("fail");
                        Synchronize(Form1->write);                        
                        break;
                }



        }
}

[Bubba]

Regardless of compiler a simple windows kernel synchronization object will work.