QT Multiple threads for data transfer

in the usual project program, it is often necessary to process multipleSerial Portand the network sent overData, and the data volume is relatively large, 9600 baud rate at least 1000 bytes per second data needs to be processed and reflected inInterface, the same thread that started directly with the UI thread, ran on the x86 machine .problem, after all, X86 the minimum frequency of the machine will not be less than 1.6G, but if the amount of data is larger or to the arm run, the direct UI stuck, think of the solution is to use multi-threading, a thread responsible for collecting data, a thread responsible for processing data, when the protocol, if necessary to the data parsing from the serial port to the network data, the previous method is to re-write a TCP communication processing, this is not a very reasonable approach, after all, the resolution protocol is the same, so I summed up a general idea of data processing: a variety of information received in the form of the back row of the queue into a global variable, Open a separate thread to read the first data from this global variable, and then remove the first data, the list of QT directly provides a takefirst function, very cool! Use the while loop to read and lock while reading, so that there is no conflict.
prototype:
Global Variablesfile:

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1. #ifndef App_h

2. #define App_h

3. 
   

4. #include "qstring.h"

5. #include "qstringlist.h"

6. 
   

7. Class APP

8. {

9. Public

10. Static Qstringlist list;

11. 
    

12. };

13. 
    

14. #endif//app_h

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1. #include "app.h"

2. 
   

3. Qstringlist app::list=qstringlist ();

Processing Data Threads independently:

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2. #ifndef Test_h

4. #define Test_h

6. 
   

8. #include "qthread.h"

10. #include "qmutex.h"

12. 
    

14. Class Thread:public Qthread

16. {

18. Q_object

20. Public

22. Thread ();

24. ~thread ();

26. 
    

28. void Stop ();

30. 
    

32. Protected

34. void Run ();

36. 
    

38. Private

40. Qmutex mutex;

42. volatile BOOL stopped;

44. 
    

46. Signals:

48. void Readone (QString txt);

50. 
    

52. };

54. 
    

56. #endif//test_h

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2. #include "thread.h"

4. #include "app.h"

6. 
   

8. Thread::thread ()

10. {

12. stopped=false;

14. }

16. 
    

18. Thread::~thread ()

20. {

22. 
    

24. }

26. 
    

28. void Thread::stop ()

30. {

32. stopped=true;

34. }

36. 
    

38. void Thread::run ()

40. {

42. While (!stopped) {

44. Mutex.lock ();

46. If (app::list.count () >0) {

48. QString Txt=app::list.takefirst ();

50. Emit Readone (txt);

52. }

54. Mutex.unlock ();

56. Msleep (1);//do Not add this sentence CPU usage up to 50%

58. }

60. stopped=false;

62. }

Main interface:

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2. #ifndef Widget_h

4. #define Widget_h

6. 
   

8. #include <QWidget>

10. #include "thread.h"

12. #include "qtimer.h"

14. 
    

16. Namespace Ui {

18. Class frmmain;

20. }

22. 
    

24. Class Frmmain:public Qwidget

26. {

28. Q_object

30. 
    

32. Public

34. Explicit frmmain (qwidget *parent = 0);

36. ~frmmain ();

38. 
    

40. Private Slots:

42. void Writeone ();

44. void Readone (QString txt);

46. void on_btnappend_clicked ();

48. void on_btnthread_clicked ();

50. void on_btntimer_clicked ();

52. 
    

54. Private

56. Ui::frmmain *ui;

58. 
    

60. Qtimer *timer;

62. Thread *thread;

64. 
    

66. };

68. 
    

70. #endif//widget_h

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2. #include "frmmain.h"

4. #include "ui_frmmain.h"

6. #include "app.h"

8. #include "qdatetime.h"

10. #include "qdesktopwidget.h"

12. 
    

14. #define _TIME_ qprintable (qtime::currenttime (). toString ("now:hh:mm:ss:zzz"))

16. 
    

18. Frmmain::frmmain (qwidget *parent):

20. Qwidget (parent),

22. UI (new Ui::frmmain)

24. {

26. Ui->setupui (this);

28. 
    

30. This->showmaximized ();

32. 
    

34. Timer=new Qtimer (this);

36. Timer->setinterval (50);

38. Connect (timer,signal ()-timeout ()), this,slot (writeone ()));

40. 
    

42. Thread=new Thread;

44. Connect (thread,signal (readone (QString)), this,slot (readone (QString)));

46. }

48. 
    

50. Frmmain::~frmmain ()

52. {

54. Delete ui;

56. }

58. 
    

60. void Frmmain::writeone ()

62. {

64. App::list.append (_time_);

66. }

68. 
    

70. void Frmmain::readone (QString Txt)

72. {

74. Ui->txtout->append (txt);

76. }

78. 
    

80. void frmmain::on_btnappend_clicked ()

82. {

84. App::list.append (ui->txtin->text ());

86. }

88. 
    

90. void frmmain::on_btnthread_clicked ()

92. {

94. If (ui->btnthread->text () = = "start Thread") {

96. Thread->start ();

98. Ui->btnthread->settext ("stop thread");

100. Ui->txtout->append ("start Thread ok");

102. }else{

104. Thread->stop ();

106. Ui->btnthread->settext ("start thread");

108. Ui->txtout->append ("stop Thread ok");

110. }

112. }

114. 
     

116. void frmmain::on_btntimer_clicked ()

118. {

120. If (ui->btntimer->text () = = "start Timer") {

122. Timer->start ();

124. Ui->btntimer->settext ("stop timer");

126. Ui->txtout->append ("start Timer ok");

128. }else{

130. Timer->stop ();

132. Ui->btntimer->settext ("start timer");

134. Ui->txtout->append ("stop Timer ok");

136. }

138. }

in order to simulate a large amount of data, I opened a timer here for 50 milliseconds, timed to generate the current time string data into a global variable, and then placed severalButtonused to manually add strings and start stopping threads and Timers.
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Welcome to criticize suggestions and guidance! Thank you!

QT Multiple threads for data transfer