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// Copyright (C) 2023 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include "primecounter.h"
#include "ui_primecounter.h"
PrimeCounter::PrimeCounter(QWidget *parent)
: QDialog(parent), stepSize(100000), ui(setupUi())
{
// Control the concurrent operation with the QFutureWatcher
//! [1]
connect(ui->pushButton, &QPushButton::clicked,
this, [this] { start(); });
connect(&watcher, &QFutureWatcher<Element>::finished,
this, [this] { finish(); });
connect(&watcher, &QFutureWatcher<Element>::progressRangeChanged,
ui->progressBar, &QProgressBar::setRange);
connect(&watcher, &QFutureWatcher<Element>::progressValueChanged,
ui->progressBar, &QProgressBar::setValue);
//! [1]
}
PrimeCounter::~PrimeCounter()
{
watcher.cancel();
delete ui;
}
//! [3]
bool PrimeCounter::filterFunction(const Element &element)
{
// Filter for primes
if (element <= 1)
return false;
for (Element i = 2; i*i <= element; ++i) {
if (element % i == 0)
return false;
}
return true;
}
//! [3]
//! [4]
void PrimeCounter::reduceFunction(Element &out, const Element &value)
{
// Count the amount of primes.
Q_UNUSED(value);
++out;
}
//! [4]
//! [2]
void PrimeCounter::start()
{
if (ui->pushButton->isChecked()) {
ui->comboBox->setEnabled(false);
ui->pushButton->setText(tr("Cancel"));
ui->labelResult->setText(tr("Calculating ..."));
ui->labelFilter->setText(tr("Selected Reduce Option: %1").arg(ui->comboBox->currentText()));
fillElementList(ui->horizontalSlider->value() * stepSize);
timer.start();
watcher.setFuture(
QtConcurrent::filteredReduced(
&pool,
elementList,
filterFunction,
reduceFunction,
currentReduceOpt | QtConcurrent::SequentialReduce));
//! [2]
} else {
watcher.cancel();
ui->progressBar->setValue(0);
ui->comboBox->setEnabled(true);
ui->labelResult->setText(tr(""));
ui->pushButton->setText(tr("Start"));
ui->labelFilter->setText(tr("Operation Canceled"));
}
}
void PrimeCounter::finish()
{
// The finished signal from the QFutureWatcher is also emitted when cancelling.
if (watcher.isCanceled())
return;
auto elapsedTime = timer.elapsed();
ui->progressBar->setValue(0);
ui->comboBox->setEnabled(true);
ui->pushButton->setChecked(false);
ui->pushButton->setText(tr("Start"));
ui->labelFilter->setText(
tr("Filter '%1' took %2 ms to calculate").arg(ui->comboBox->currentText())
.arg(elapsedTime));
ui->labelResult->setText(
tr("Found %1 primes in the range of elements").arg(watcher.result()));
}
void PrimeCounter::fillElementList(unsigned int count)
{
// Fill elementList with values from [1, count] when starting the calculations.
auto prevSize = elementList.size();
if (prevSize == count)
return; // Nothing to do here.
auto startVal = elementList.empty() ? 1 : elementList.back() + 1;
elementList.resize(count);
if (elementList.begin() + prevSize < elementList.end())
std::iota(elementList.begin() + prevSize, elementList.end(), startVal);
}
Ui::PrimeCounter* PrimeCounter::setupUi()
{
Ui::PrimeCounter *setupUI = new Ui::PrimeCounter;
setupUI->setupUi(this);
setModal(true);
// Set up the slider
connect(setupUI->horizontalSlider, &QSlider::valueChanged,
this, [setupUI, this] (const int &pos) {
setupUI->labelResult->setText("");
setupUI->labelSize->setText(tr("Elements in list: %1").arg(pos * stepSize));
});
setupUI->horizontalSlider->setValue(30);
// Set up the combo box
setupUI->comboBox->insertItem(0, tr("Unordered Reduce"), QtConcurrent::UnorderedReduce);
setupUI->comboBox->insertItem(1, tr("Ordered Reduce"), QtConcurrent::OrderedReduce);
auto comboBoxChange = [this, setupUI](int pos) {
currentReduceOpt = setupUI->comboBox->itemData(pos).value<QtConcurrent::ReduceOptions>();
setupUI->labelFilter->setText(tr("Selected Reduce Option: %1")
.arg(setupUI->comboBox->currentText()));
};
comboBoxChange(setupUI->comboBox->currentIndex());
connect(setupUI->comboBox, &QComboBox::currentIndexChanged, this, comboBoxChange);
return setupUI;
}
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