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GuiMT

 

Using event queue for communication between worker threads and GUI

 

 

 

main.cpp

 

#include "CtrlLib/CtrlLib.h"

 

using namespace Upp;

 

#define LAYOUTFILE <GuiMT/Divisors.lay>

#include <CtrlCore/lay.h>

 

// This example shows older way how to do multithreded GUI using PostCallback to communicate

// between worker thread and main GUI thread.

// While PostCallback is still useful in certain circumstances, new applications are

// perhaps better off using GuiLock and Call, as demostrated in GuiLock reference example.

 

struct Divisors : public WithDivisorsLayout<TopWindow> {

    volatile Atomic terminated;

    volatile Atomic threads;

 

    void TestNumber();

    void ShowResult(int line, String result);

    void SetTitle();

 

    Divisors();

    ~Divisors();

};

 

 

struct DivisorsInfo {

    int       line;

    uint64    number;

    Divisors *gui;

};

 

void WorkerThread(DivisorsInfo f)

{

    String r1, r2;

    int divisors = 0;

    uint64 max = (uint64)sqrt((double)f.number) + 1;

    for(uint64 i = 1; i < max; i++) {

        if(f.gui->terminated)

            break;

        if(f.number % i == 0) {

            r1 << ' ' << i;

            divisors++;

            uint64 j = f.number / i;

            if (j != i) {

                r2 = " " + AsString(j) + r2;

                divisors++;

            }

            PostCallback([=] { f.gui->ShowResult(f.line, "working..." + r1 + r2); });

        }

    }

    PostCallback([=] { f.gui->ShowResult(f.line, AsString(divisors) + ": " + r1 + r2); });

    AtomicDec(f.gui->threads);

}

 

void Divisors::TestNumber()

{

    if(IsNull(editor))

        return;

    DivisorsInfo f;

    f.number = stou64((String)~editor);

    f.line = table.GetCount();

    table.Add(AsString(f.number), "working...");

    f.gui = this;

    AtomicInc(threads);

    Thread().Run(callback1(WorkerThread, f));

    SetTitle();

}

 

void Divisors::ShowResult(int line, String result)

{

    table.Set(line, 1, result);

    SetTitle();

}

 

void Divisors::SetTitle()

{

    int n = threads;

    Title(AsString(n) + " threads");

}

 

Divisors::Divisors()

{

    CtrlLayout(*this, "Window title");

    Sizeable().Zoomable();

    push << [=] { TestNumber(); };

    editor.SetFilter(CharFilterDigit);

    table.AddColumn("Number");

    table.AddColumn("Divisors");

    table.ColumnWidths("135 527");

    table.NoCursor();

    terminated = 0;

    threads = 0;

    SetTitle();

}

 

Divisors::~Divisors()

{

    terminated = 1;

    while(threads)

        Sleep(10);

}

 

GUI_APP_MAIN

{

    Divisors().Run();

}

 

 

 

Divisors.lay

 

LAYOUT(DivisorsLayout, 700, 440)

    ITEM(ArrayCtrl, table, HSizePosZ(12, 12).VSizePosZ(12, 36))

    ITEM(Button, push, SetLabel(t_("Test")).LeftPosZ(184, 84).BottomPosZ(9, 19))

    ITEM(EditString, editor, LeftPosZ(12, 164).BottomPosZ(9, 19))

END_LAYOUT

 

 

 

 

 

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