conversionscreen.cpp

QT/X11(版本为4.2.2)下的功能丰富(含存储数据,窗口对话,温度转换)的完整代码

#include <QPushButton>
#include <QSlider>
#include <QLabel>
#include <QDial>
#include <QLCDNumber>
#include <QVBoxLayout>
#include <QHBoxLayout>
#include <QGridLayout>
#include <QSettings>
#include <QApplication>
#include <QCoreApplication>

#include "ConversionScreen.h"

ConversionScreen::ConversionScreen() : QWidget()
{
    initSettings();
    readSettings();
    createScreen();
}

void ConversionScreen::createScreen()
{
    QPushButton* quitBtn = new QPushButton("Quit");
    QPushButton* saveBtn = new QPushButton("Save");

    createCel();
    createFah();

    QGridLayout *mainLayout = new QGridLayout;
    mainLayout->addWidget(quitBtn, 0, 0);
    mainLayout->addWidget(saveBtn, 0, 1);
    mainLayout->addLayout(celLayout, 1, 0);
    mainLayout->addLayout(fahLayout, 1, 1);
    mainLayout->setSpacing(40);
    mainLayout->setMargin(40);
    setLayout(mainLayout);

    slider->setFocus();
    
    connect(quitBtn, SIGNAL(clicked()), qApp, SLOT(quit()));
    connect(saveBtn, SIGNAL(clicked()), this, SLOT(saveSettings()));

    setWindowTitle("Temperature Conversion");
}

void ConversionScreen::createCel()
{
    slider = new QSlider(Qt::Vertical);
    slider->setRange(0, 100);
    slider->setValue(currentCelNum);
    slider->setTickPosition(QSlider::TicksLeft);
    
    QLabel* celLabel = new QLabel(QString::number(currentCelNum));
    
    celLayout = new QHBoxLayout;
    celLayout->addWidget(celLabel, 0, Qt::AlignRight);
    celLayout->addWidget(slider, 0, Qt::AlignLeft);    
    celLayout->setSpacing(10);

    connect(slider, SIGNAL(valueChanged(int)), celLabel, SLOT(setNum(int)));
    connect(slider, SIGNAL(valueChanged(int)), this, SLOT(celToFah(int)));
}

void ConversionScreen::createFah()
{
    QLCDNumber* lcdNum = new QLCDNumber(3);
    lcdNum->setSegmentStyle(QLCDNumber::Filled);
    lcdNum->display(currentFahNum);
   
    dial = new QDial;
    dial->setRange(32, 212);
    dial->setValue(currentFahNum);
    dial->setNotchesVisible(true);
    
    fahLayout = new QVBoxLayout;
    fahLayout->addWidget(lcdNum, 0, Qt::AlignBottom | Qt::AlignHCenter);
    fahLayout->addWidget(dial);
    fahLayout->setSpacing(10);
    
    connect(dial, SIGNAL(valueChanged(int)), lcdNum, SLOT(display(int)));
    connect(dial, SIGNAL(valueChanged(int)), this, SLOT(fahToCel(int)));
}

void ConversionScreen::celToFah(int celNum)
{
    int fahNum = (celNum * 9 / 5) + 32;
    dial->setValue(fahNum);
}

void ConversionScreen::fahToCel(int fahNum)
{
    int celNum = (fahNum - 32) * 5 / 9;
    slider->setValue(celNum);
}

void ConversionScreen::initSettings()
{
    QCoreApplication::setOrganizationName("MySoft");
    QCoreApplication::setApplicationName("Conversion");
}

void ConversionScreen::saveSettings()
{
    currentCelNum = slider->value();
    currentFahNum = dial->value();
    
    QSettings settings;
    settings.setValue("Temperature/CelNumber", currentCelNum);
    settings.setValue("Temperature/FahNumber", currentFahNum);
}

void ConversionScreen::readSettings()
{
    QSettings settings;
    currentCelNum = settings.value("Temperature/CelNumber", 0).toInt();
    currentFahNum = settings.value("Temperature/FahNumber", 32).toInt();
}