wxWidgets/samples/thread/thread.cpp
Bryan Petty f6bcfd974e merged 2.2 branch
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@7748 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
2000-07-15 19:51:35 +00:00

622 lines
15 KiB
C++

/////////////////////////////////////////////////////////////////////////////
// Name: thread.cpp
// Purpose: wxWindows thread sample
// Author: Julian Smart(minimal)/Guilhem Lavaux(thread test)
// Modified by:
// Created: 06/16/98
// RCS-ID: $Id$
// Copyright: (c) Julian Smart, Markus Holzem, Guilhem Lavaux
// Licence: wxWindows license
/////////////////////////////////////////////////////////////////////////////
/*
TODO: use worker threads to update progress controls instead of writing
messages - it will be more visual
*/
// For compilers that support precompilation, includes "wx/wx.h".
#include "wx/wxprec.h"
#ifdef __BORLANDC__
#pragma hdrstop
#endif
#ifndef WX_PRECOMP
#include "wx/wx.h"
#endif
#if !wxUSE_THREADS
#error "This sample requires thread support!"
#endif // wxUSE_THREADS
#include "wx/thread.h"
#include "wx/dynarray.h"
#include "wx/time.h"
#include "wx/progdlg.h"
// uncomment this to get some debugging messages from the trace code
//#define TRACE
class MyThread;
WX_DEFINE_ARRAY(wxThread *, wxArrayThread);
// Define a new application type
class MyApp : public wxApp
{
public:
virtual bool OnInit();
public:
// all the threads currently alive - as soon as the thread terminates, it's
// removed from the array
wxArrayThread m_threads;
// crit section protects access to all of the arrays below
wxCriticalSection m_critsect;
};
// Create a new application object
IMPLEMENT_APP(MyApp)
// Define a new frame type
class MyFrame: public wxFrame
{
public:
// ctor
MyFrame(wxFrame *frame, const wxString& title, int x, int y, int w, int h);
// operations
void WriteText(const wxString& text) { m_txtctrl->WriteText(text); }
// accessors for MyWorkerThread (called in its context!)
bool Cancelled();
// callbacks
void OnQuit(wxCommandEvent& event);
void OnAbout(wxCommandEvent& event);
void OnClear(wxCommandEvent& event);
void OnStartThread(wxCommandEvent& event);
void OnStartThreads(wxCommandEvent& event);
void OnStopThread(wxCommandEvent& event);
void OnPauseThread(wxCommandEvent& event);
void OnResumeThread(wxCommandEvent& event);
void OnStartWorker(wxCommandEvent& event);
void OnWorkerEvent(wxCommandEvent& event);
void OnUpdateWorker(wxUpdateUIEvent& event);
void OnIdle(wxIdleEvent &event);
private:
// helper function - creates a new thread (but doesn't run it)
MyThread *CreateThread();
// just some place to put our messages in
wxTextCtrl *m_txtctrl;
// remember the number of running threads and total number of threads
size_t m_nRunning, m_nCount;
// the progress dialog which we show while worker thread is running
wxProgressDialog *m_dlgProgress;
// was the worker thread cancelled by user?
bool m_cancelled;
// protects m_cancelled
wxCriticalSection m_critsectWork;
DECLARE_EVENT_TABLE()
};
// ID for the menu commands
enum
{
TEST_QUIT = 1,
TEST_TEXT = 101,
TEST_ABOUT,
TEST_CLEAR,
TEST_START_THREAD = 201,
TEST_START_THREADS,
TEST_STOP_THREAD,
TEST_PAUSE_THREAD,
TEST_RESUME_THREAD,
TEST_START_WORKER,
WORKER_EVENT // this one gets sent from the worker thread
};
//--------------------------------------------------
// GUI thread
//--------------------------------------------------
class MyThread : public wxThread
{
public:
MyThread(MyFrame *frame);
// thread execution starts here
virtual void *Entry();
// called when the thread exits - whether it terminates normally or is
// stopped with Delete() (but not when it is Kill()ed!)
virtual void OnExit();
// write something to the text control
void WriteText(const wxString& text);
public:
size_t m_count;
MyFrame *m_frame;
};
MyThread::MyThread(MyFrame *frame)
: wxThread()
{
m_count = 0;
m_frame = frame;
}
void MyThread::WriteText(const wxString& text)
{
wxString msg;
// before doing any GUI calls we must ensure that this thread is the only
// one doing it!
wxMutexGuiEnter();
msg << text;
m_frame->WriteText(msg);
wxMutexGuiLeave();
}
void MyThread::OnExit()
{
wxCriticalSectionLocker locker(wxGetApp().m_critsect);
wxGetApp().m_threads.Remove(this);
}
void *MyThread::Entry()
{
wxString text;
text.Printf("Thread 0x%x started (priority = %d).\n",
GetId(), GetPriority());
WriteText(text);
// wxLogMessage(text); -- test wxLog thread safeness
for ( m_count = 0; m_count < 10; m_count++ )
{
// check if we were asked to exit
if ( TestDestroy() )
break;
text.Printf("[%u] Thread 0x%x here.\n", m_count, GetId());
WriteText(text);
// wxSleep() can't be called from non-GUI thread!
wxThread::Sleep(1000);
}
text.Printf("Thread 0x%x finished.\n", GetId());
WriteText(text);
// wxLogMessage(text); -- test wxLog thread safeness
return NULL;
}
//--------------------------------------------------
// worker thread
//--------------------------------------------------
class MyWorkerThread : public wxThread
{
public:
MyWorkerThread(MyFrame *frame);
// thread execution starts here
virtual void *Entry();
// called when the thread exits - whether it terminates normally or is
// stopped with Delete() (but not when it is Kill()ed!)
virtual void OnExit();
public:
MyFrame *m_frame;
size_t m_count;
};
MyWorkerThread::MyWorkerThread(MyFrame *frame)
: wxThread()
{
m_frame = frame;
m_count = 0;
}
void MyWorkerThread::OnExit()
{
}
void *MyWorkerThread::Entry()
{
for ( m_count = 0; !m_frame->Cancelled() && (m_count < 100); m_count++ )
{
// check if we were asked to exit
if ( TestDestroy() )
break;
wxString text;
text.Printf("[%u] Thread 0x%x here!!", m_count, GetId());
// create any type of command event here
wxCommandEvent event( wxEVT_COMMAND_MENU_SELECTED, WORKER_EVENT );
event.SetInt( m_count );
event.SetString( text );
// send in a thread-safe way
wxPostEvent( m_frame, event );
// same as:
// m_frame->AddPendingEvent( event );
// wxSleep() can't be called from non-main thread!
wxThread::Sleep(200);
}
wxCommandEvent event( wxEVT_COMMAND_MENU_SELECTED, WORKER_EVENT );
event.SetInt(-1); // that's all
wxPostEvent( m_frame, event );
return NULL;
}
//--------------------------------------------------
// main program
//--------------------------------------------------
BEGIN_EVENT_TABLE(MyFrame, wxFrame)
EVT_MENU(TEST_QUIT, MyFrame::OnQuit)
EVT_MENU(TEST_ABOUT, MyFrame::OnAbout)
EVT_MENU(TEST_CLEAR, MyFrame::OnClear)
EVT_MENU(TEST_START_THREAD, MyFrame::OnStartThread)
EVT_MENU(TEST_START_THREADS, MyFrame::OnStartThreads)
EVT_MENU(TEST_STOP_THREAD, MyFrame::OnStopThread)
EVT_MENU(TEST_PAUSE_THREAD, MyFrame::OnPauseThread)
EVT_MENU(TEST_RESUME_THREAD, MyFrame::OnResumeThread)
EVT_UPDATE_UI(TEST_START_WORKER, MyFrame::OnUpdateWorker)
EVT_MENU(TEST_START_WORKER, MyFrame::OnStartWorker)
EVT_MENU(WORKER_EVENT, MyFrame::OnWorkerEvent)
EVT_IDLE(MyFrame::OnIdle)
END_EVENT_TABLE()
// `Main program' equivalent, creating windows and returning main app frame
bool MyApp::OnInit()
{
#ifdef TRACE
wxLog::AddTraceMask("thread");
#endif
// Create the main frame window
MyFrame *frame = new MyFrame((wxFrame *)NULL, "wxWindows threads sample",
50, 50, 450, 340);
// Make a menubar
wxMenu *file_menu = new wxMenu;
file_menu->Append(TEST_CLEAR, "&Clear log\tCtrl-L");
file_menu->AppendSeparator();
file_menu->Append(TEST_ABOUT, "&About");
file_menu->AppendSeparator();
file_menu->Append(TEST_QUIT, "E&xit\tAlt-X");
wxMenuBar *menu_bar = new wxMenuBar;
menu_bar->Append(file_menu, "&File");
wxMenu *thread_menu = new wxMenu;
thread_menu->Append(TEST_START_THREAD, "&Start a new thread\tCtrl-N");
thread_menu->Append(TEST_START_THREADS, "Start &many threads at once");
thread_menu->Append(TEST_STOP_THREAD, "S&top a running thread\tCtrl-S");
thread_menu->AppendSeparator();
thread_menu->Append(TEST_PAUSE_THREAD, "&Pause a running thread\tCtrl-P");
thread_menu->Append(TEST_RESUME_THREAD, "&Resume suspended thread\tCtrl-R");
thread_menu->AppendSeparator();
thread_menu->Append(TEST_START_WORKER, "Start &worker thread\tCtrl-W");
menu_bar->Append(thread_menu, "&Thread");
frame->SetMenuBar(menu_bar);
// Show the frame
frame->Show(TRUE);
SetTopWindow(frame);
return TRUE;
}
// My frame constructor
MyFrame::MyFrame(wxFrame *frame, const wxString& title,
int x, int y, int w, int h)
: wxFrame(frame, -1, title, wxPoint(x, y), wxSize(w, h))
{
m_nRunning = m_nCount = 0;
m_dlgProgress = (wxProgressDialog *)NULL;
CreateStatusBar(2);
m_txtctrl = new wxTextCtrl(this, -1, "", wxPoint(0, 0), wxSize(0, 0),
wxTE_MULTILINE | wxTE_READONLY);
}
MyThread *MyFrame::CreateThread()
{
MyThread *thread = new MyThread(this);
if ( thread->Create() != wxTHREAD_NO_ERROR )
{
wxLogError("Can't create thread!");
}
wxCriticalSectionLocker enter(wxGetApp().m_critsect);
wxGetApp().m_threads.Add(thread);
return thread;
}
void MyFrame::OnStartThreads(wxCommandEvent& WXUNUSED(event) )
{
static long s_num = 10;
s_num = wxGetNumberFromUser("How many threads to start: ", "",
"wxThread sample", s_num, 1, 10000, this);
if ( s_num == -1 )
{
s_num = 10;
return;
}
size_t count = (size_t)s_num, n;
wxArrayThread threads;
// first create them all...
for ( n = 0; n < count; n++ )
{
wxThread *thr = CreateThread();
// we want to show the effect of SetPriority(): the first thread will
// have the lowest priority, the second - the highest, all the rest
// the normal one
if ( n == 0 )
thr->SetPriority(WXTHREAD_MIN_PRIORITY);
else if ( n == 1 )
thr->SetPriority(WXTHREAD_MAX_PRIORITY);
else
thr->SetPriority(WXTHREAD_DEFAULT_PRIORITY);
threads.Add(thr);
}
wxString msg;
msg.Printf("%d new threads created.", count);
SetStatusText(msg, 1);
// ...and then start them
for ( n = 0; n < count; n++ )
{
threads[n]->Run();
}
}
void MyFrame::OnStartThread(wxCommandEvent& WXUNUSED(event) )
{
MyThread *thread = CreateThread();
if ( thread->Run() != wxTHREAD_NO_ERROR )
{
wxLogError("Can't start thread!");
}
SetStatusText("New thread started.", 1);
}
void MyFrame::OnStopThread(wxCommandEvent& WXUNUSED(event) )
{
wxGetApp().m_critsect.Enter();
// stop the last thread
if ( wxGetApp().m_threads.IsEmpty() )
{
wxLogError("No thread to stop!");
wxGetApp().m_critsect.Leave();
}
else
{
wxThread *thread = wxGetApp().m_threads.Last();
// it's important to leave critical section before calling Delete()
// because delete will (implicitly) call OnExit() which also tries
// to enter the same crit section - would dead lock.
wxGetApp().m_critsect.Leave();
thread->Delete();
SetStatusText("Thread stopped.", 1);
}
}
void MyFrame::OnResumeThread(wxCommandEvent& WXUNUSED(event) )
{
wxCriticalSectionLocker enter(wxGetApp().m_critsect);
// resume first suspended thread
size_t n = 0, count = wxGetApp().m_threads.Count();
while ( n < count && !wxGetApp().m_threads[n]->IsPaused() )
n++;
if ( n == count )
{
wxLogError("No thread to resume!");
}
else
{
wxGetApp().m_threads[n]->Resume();
SetStatusText("Thread resumed.", 1);
}
}
void MyFrame::OnPauseThread(wxCommandEvent& WXUNUSED(event) )
{
wxCriticalSectionLocker enter(wxGetApp().m_critsect);
// pause last running thread
int n = wxGetApp().m_threads.Count() - 1;
while ( n >= 0 && !wxGetApp().m_threads[n]->IsRunning() )
n--;
if ( n < 0 )
{
wxLogError("No thread to pause!");
}
else
{
wxGetApp().m_threads[n]->Pause();
SetStatusText("Thread paused.", 1);
}
}
// set the frame title indicating the current number of threads
void MyFrame::OnIdle(wxIdleEvent &event)
{
// update the counts of running/total threads
size_t nRunning = 0,
nCount = wxGetApp().m_threads.Count();
for ( size_t n = 0; n < nCount; n++ )
{
if ( wxGetApp().m_threads[n]->IsRunning() )
nRunning++;
}
if ( nCount != m_nCount || nRunning != m_nRunning )
{
m_nRunning = nRunning;
m_nCount = nCount;
wxLogStatus(this, "%u threads total, %u running.", nCount, nRunning);
}
//else: avoid flicker - don't print anything
}
void MyFrame::OnQuit(wxCommandEvent& WXUNUSED(event) )
{
size_t count = wxGetApp().m_threads.Count();
for ( size_t i = 0; i < count; i++ )
{
wxGetApp().m_threads[0]->Delete();
}
Close(TRUE);
}
void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event) )
{
wxMessageDialog dialog(this, "wxWindows multithreaded application sample\n"
"(c) 1998 Julian Smart, Guilhem Lavaux\n"
"(c) 1999 Vadim Zeitlin\n"
"(c) 2000 Robert Roebling",
"About wxThread sample",
wxOK | wxICON_INFORMATION);
dialog.ShowModal();
}
void MyFrame::OnClear(wxCommandEvent& WXUNUSED(event))
{
#ifdef TRACE
// log a separator
wxLogTrace("-------- log window cleared --------");
#endif
m_txtctrl->Clear();
}
void MyFrame::OnUpdateWorker(wxUpdateUIEvent& event)
{
event.Enable( m_dlgProgress == NULL );
}
void MyFrame::OnStartWorker(wxCommandEvent& WXUNUSED(event))
{
MyWorkerThread *thread = new MyWorkerThread(this);
if ( thread->Create() != wxTHREAD_NO_ERROR )
{
wxLogError("Can't create thread!");
}
m_dlgProgress = new wxProgressDialog
(
"Progress dialog",
"Wait until the thread terminates or press [Cancel]",
100,
this,
wxPD_CAN_ABORT |
wxPD_APP_MODAL |
wxPD_ELAPSED_TIME |
wxPD_ESTIMATED_TIME |
wxPD_REMAINING_TIME
);
// thread is not running yet, no need for crit sect
m_cancelled = FALSE;
thread->Run();
}
void MyFrame::OnWorkerEvent(wxCommandEvent& event)
{
#if 0
WriteText( "Got message from worker thread: " );
WriteText( event.GetString() );
WriteText( "\n" );
#else
int n = event.GetInt();
if ( n == -1 )
{
m_dlgProgress->Destroy();
m_dlgProgress = (wxProgressDialog *)NULL;
// the dialog is aborted because the event came from another thread, so
// we may need to wake up the main event loop for the dialog to be
// really closed
wxWakeUpIdle();
}
else
{
if ( !m_dlgProgress->Update(n) )
{
wxCriticalSectionLocker lock(m_critsectWork);
m_cancelled = TRUE;
}
}
#endif
}
bool MyFrame::Cancelled()
{
wxCriticalSectionLocker lock(m_critsectWork);
return m_cancelled;
}