Qt, multithreading context switching with QRadioButtons - c++

Question

Hi guys so I'm try switch between different threads with the way I have now by having users switch back and forth between multiple radio buttons (here I have only shown 2), when they switch the program freezes. I want to essentially create a thread, stop it then create another thread when I'm doing radio button switching. How do I accomplish this?
mainwindow.cpp
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
s1_thread = new skype_thread(this);
connect(s1_thread, SIGNAL(skype_sig(int)), this, SLOT(skype_change(int)));
x1_thread = new xlite_thread(this);
connect(x1_thread, SIGNAL(xlite_sig(int)), this, SLOT(xlite_change(int)));
}
void MainWindow::on_radioButton_3_toggled(bool checked) //Skype Application is checked
{
x1_thread->stop=true;
s1_thread->start();
}
void MainWindow::on_radioButton_toggled(bool checked) //X-Lite Application is checked
{
s1_thread->stop=true;
x1_thread->start();
}
skype_thread.cpp:
void skype_thread::run()
{
int err;
int skype_signal=0;
//Add programs you would like to use telephony hid here.
wchar_t skype[6] = L"Skype";
unsigned char data_usb[2];
int transfer_size = 4;
//Keyboard input event
INPUT ip;
//Device Handle
libusb_device_handle* dev;
//Initialize libusb with default device
libusb_init(NULL);
//Check whether the Red Button is meant to be a Hangup or Reject Button.
bool check_d = 0;
//Open Device VID = 0x04B4, PID = 0xE002 with the default libusb context
dev = libusb_open_device_with_vid_pid(NULL, VID, PID);
//Claim interface 3 on the device
err = libusb_claim_interface(dev, 3);
//Get first window on desktop
HWND firstwindow = FindWindowEx(NULL, NULL, NULL, NULL);
HWND window = firstwindow;
wchar_t windowtext[MAX_PATH]; //search term
//We need to get the console title in case we
//accidentally match the search word with it
//instead of the intended target window.
wchar_t consoletitle[MAX_PATH];
GetConsoleTitle(consoletitle, MAX_PATH);
//Error message for when window isn't found.
QString error_msg = NULL;
while(true){
//Check window title for a match
GetWindowText(window, windowtext, MAX_PATH);
if (wcsstr(windowtext, skype)!=NULL && wcscmp(windowtext, consoletitle)!=0) break; //search for program
window = FindWindowEx(NULL, window, NULL, NULL); //Get next window
}
while(true){
QMutex mutex;
mutex.lock();
//Differentiate the different button presses.
//Interrupt IN transfer
err = libusb_interrupt_transfer(dev, LIBUSB_ENDPOINT_IN | EP_IN, data_usb, sizeof(data_usb), &transfer_size, 1000);
if(transfer_size > 0){
if(data_usb[0]==0x02 && data_usb[1]==0x04){ //Pickup Button Payload
printf("Window found: %ls\n", windowtext);
//Press the "Alt" key
ip.ki.wVk = 0x12; // virtual-key code for the "Alt" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Release the "Alt" key
ip.ki.wVk = 0x12;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
//Bring specified window into focus
SetForegroundWindow(window);
//Press the "Alt" key
ip.ki.wVk = 0x12; // virtual-key code for the "alt" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Press the "Pageup" key
ip.ki.wVk = 0x21; // virtual-key code for the "pageup" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Release the "Pageup" key
ip.ki.wVk = 0x21;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
//Release the "Alt" key
ip.ki.wVk = 0x12;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
check_d = 1;
}
if(data_usb[0]==0x02 && data_usb[1]==0x01 && check_d==1){ //Disconnect Button Payload
//Press the "Alt" key
ip.ki.wVk = 0x12; // virtual-key code for the "Alt" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Release the "Alt" key
ip.ki.wVk = 0x12;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
//Bring specified window into focus
SetForegroundWindow(window);
//Press the "Alt" key
ip.ki.wVk = 0x12; // virtual-key code for the "alt" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Press the "Pagedown" key
ip.ki.wVk = 0x22; // virtual-key code for the "pageup" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Release the "Pagedown" key
ip.ki.wVk = 0x22;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
//Release the "Alt" key
ip.ki.wVk = 0x12;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
check_d = 0;
}//end if
if(data_usb[0]==0x02 && data_usb[1]==0x01 && check_d==0){ //Reject Button Payload
//Press the "Alt" key
ip.ki.wVk = 0x12; // virtual-key code for the "Alt" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Release the "Alt" key
ip.ki.wVk = 0x12;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
//Bring specified window into focus
SetForegroundWindow(window);
//Press the "Ctrl"Key
ip.ki.wVk = 0x11; // virtual-key code for the "alt" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Press the "Alt" key
ip.ki.wVk = 0x12; // virtual-key code for the "alt" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Press the "Pagedown" key
ip.ki.wVk = 0x22; // virtual-key code for the "pageup" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Release the "Pagedown" key
ip.ki.wVk = 0x22;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
//Release the "Alt" key
ip.ki.wVk = 0x12;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
//Release the "Ctrl" key
ip.ki.wVk = 0x11;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
check_d = 0;
}//end if
}//end if
if(this->stop) break;
mutex.unlock();
emit skype_sig(skype_signal);
skype_signal++;
} //end while
}
xlite_thread.cpp
void xlite_thread::run()
{
int xlite_signal=0;
int err;
//Add programs you would like to use telephony hid here.
wchar_t xlite[7] = L"X-Lite";
unsigned char data_usb[2];
int transfer_size = 4;
//Keyboard input event
INPUT ip;
//Device Handle
libusb_device_handle* dev;
//Initialize libusb with default device
libusb_init(NULL);
//Check whether the Red Button is meant to be a Hangup or Reject Button.
bool check_d = 0;
//Open Device VID = 0x04B4, PID = 0xE002 with the default libusb context
dev = libusb_open_device_with_vid_pid(NULL, VID, PID);
//Claim interface 3 on the device
err = libusb_claim_interface(dev, 3);
//Get first window on desktop
HWND firstwindow = FindWindowEx(NULL, NULL, NULL, NULL);
HWND window = firstwindow;
wchar_t windowtext[MAX_PATH]; //search term
//We need to get the console title in case we
//accidentally match the search word with it
//instead of the intended target window.
wchar_t consoletitle[MAX_PATH];
GetConsoleTitle(consoletitle, MAX_PATH);
//Error message for when window isn't found.
QString error_msg = NULL;
while(true){
//Check window title for a match
GetWindowText(window, windowtext, MAX_PATH);
if (wcsstr(windowtext, xlite)!=NULL && wcscmp(windowtext, consoletitle)!=0) break; //search for program
window = FindWindowEx(NULL, window, NULL, NULL); //Get next window
}
while(true){
QMutex mutex;
mutex.lock();
//Differentiate the different button presses.
//Interrupt IN transfer
err = libusb_interrupt_transfer(dev, LIBUSB_ENDPOINT_IN | EP_IN, data_usb, sizeof(data_usb), &transfer_size, 1000);
if(transfer_size > 0){
if(data_usb[0]==0x02 && data_usb[1]==0x04){ //Pickup Button Payload
printf("Window found: %ls\n", windowtext);
//Press the "Alt" key
ip.ki.wVk = 0x12; // virtual-key code for the "Alt" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Release the "Alt" key
ip.ki.wVk = 0x12;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
//Bring specified window into focus
SetForegroundWindow(window);
//Press the "Ctrl" key
ip.ki.wVk = 0xA2; // virtual-key code for the "alt" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Press the "N" key
ip.ki.wVk = 0x4E; // virtual-key code for the "pageup" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Release the "N" key
ip.ki.wVk = 0x4E;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
//Release the "Ctrl" key
ip.ki.wVk = 0xA2;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
check_d = 1;
}
if(data_usb[0]==0x02 && data_usb[1]==0x01 && check_d==1){ //Disconnect Button Payload
//Press the "Alt" key
ip.ki.wVk = 0x12; // virtual-key code for the "Alt" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Release the "Alt" key
ip.ki.wVk = 0x12;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
//Bring specified window into focus
SetForegroundWindow(window);
//Press the "Ctrl" key
ip.ki.wVk = 0xA2; // virtual-key code for the "alt" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Press the "E" key
ip.ki.wVk = 0x45; // virtual-key code for the "pageup" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Release the "E" key
ip.ki.wVk = 0x45;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
//Release the "Ctrl" key
ip.ki.wVk = 0xA2;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
check_d = 0;
}//end if
if(data_usb[0]==0x02 && data_usb[1]==0x01 && check_d==0){ //Reject Button Payload
//Press the "Alt" key
ip.ki.wVk = 0x12; // virtual-key code for the "Alt" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Release the "Alt" key
ip.ki.wVk = 0x12;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
//Bring specified window into focus
SetForegroundWindow(window);
//Press the "Ctrl" key
ip.ki.wVk = 0xA2; // virtual-key code for the "alt" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Press the "D" key
ip.ki.wVk = 0x44; // virtual-key code for the "pageup" key
ip.ki.dwFlags = 0; // 0 for key press
SendInput(1, &ip, sizeof(INPUT));
//Release the "D" key
ip.ki.wVk = 0x44;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
//Release the "Ctrl" key
ip.ki.wVk = 0xA2;
ip.ki.dwFlags = KEYEVENTF_KEYUP; // KEYEVENTF_KEYUP for key release
SendInput(1, &ip, sizeof(INPUT));
check_d = 0;
}//end if
}//end if
if(this->stop) break;
mutex.unlock();
emit xlite_sig(xlite_signal);
xlite_signal++;
} //end while
}

Answer 1

You are better off using a Object and a timer to repeatedly call a slot in the object (that is moved to a worker thread)
for example:
class SkypeObject: public QObject{
Q_OBJECT
slots:
void start();
void loop();
void stop();
signals:
//...
}
Then you trigger the start and stop slots after you move it to the background thread. Inside the loop slot you put the body of the while and trigger it by QTimer (or using startTimer and inherit timerEvent(QTimerEvent))
Also the mutex in the while loop doesn't actually do anything to protect against race conditions except leak when you exit the while when stop is true.