Qt学习第四天

头文件：

#ifndef DIALOG_H

#define DIALOG_H

#include <QDialog>

//前置申明了一些将要用到的类

class QGridLayout; //网格布局

class QVBoxLayout; //垂直布局

class QPushButton; //按钮

class QSpacerItem; //分隔符

class QGroupBox; //组合框

class QLabel; //标签

class QComboBox; //下拉框

class SortDialog:public QDialog

{

 Q_OBJECT

public:

 SortDialog(QWidget *parent = 0); //该类的构造函数

 void setColumnRange(QChar first,QChar last);

private:

 QGridLayout *gridLayout; //调整整个窗口的布局

 QSpacerItem *spacerItem; //右侧按钮组合框

 QVBoxLayout *vboxLayout;

 QPushButton *okButton;

 QPushButton *cancelButton;

 QPushButton *moreButton;

 QGroupBox *primaryGroupBox; //左侧第一个组合框

 QGridLayout *gridLayout1;

 QLabel *primaryColumnLabel;

 QComboBox *primaryColumnCombo;

 QSpacerItem *spacerItem1;

 QLabel *primaryOrderLabel;

 QComboBox *primaryOrderCombo;

 QSpacerItem *spacerItem2; //左侧第一个组合框和第二个组合框之间的分隔符

 QGroupBox *secondaryGroupBox; //左侧第二个组合框

 QGridLayout *gridLayout2;

 QLabel *secondaryColumnLabel;

 QComboBox *secondaryColumnCombo;

 QSpacerItem *spacerItem3;

 QLabel *secondaryOrderLabel;

 QComboBox *secondaryOrderCombo;

 QGroupBox *tertiaryGroupBox; //左侧第三个组合框

 QGridLayout *gridLayout3;

 QLabel *tertiaryColumnLabel;

 QComboBox *tertiaryColumnCombo;

 QSpacerItem *spacerItem4;

 QLabel *tertiaryOrderLabel;

 QComboBox *tertiaryOrderCombo;

};

#endif // DIALOG_H

实现文件：

#include<QtGui>

#include "dialog.h"

SortDialog::SortDialog(QWidget *parent)

 :QDialog(parent) //将parent传给父类

{

 okButton = new QPushButton(tr("OK"));

 okButton->setDefault(true);

 cancelButton = new QPushButton(tr("Cancel"));

 moreButton = new QPushButton(tr("&More"));

 moreButton->setCheckable(true); //默认设置为false

 spacerItem = new QSpacerItem(20, 0, QSizePolicy::Minimum,QSizePolicy::Expanding);

 //设置宽度固定为20，高度可变

 vboxLayout = new QVBoxLayout;

 vboxLayout->addWidget(okButton);

 vboxLayout->addWidget(cancelButton);

 vboxLayout->addItem(spacerItem);

 vboxLayout->addWidget(moreButton);

 primaryGroupBox = new QGroupBox(tr("&Primary Key"));

 primaryColumnLabel = new QLabel(tr("Column:"));

 primaryColumnCombo = new QComboBox;

 primaryColumnCombo->addItem(tr("None"));

 spacerItem1 = new QSpacerItem(20,20,QSizePolicy::Minimum,QSizePolicy::Expanding);  

 //设置宽度最小为20，高度可变

 primaryOrderLabel = new QLabel(tr("Order:"));

 primaryOrderCombo = new QComboBox;

 primaryOrderCombo->addItem(tr("Ascending"));

 primaryOrderCombo->addItem(tr("Descending"));

 gridLayout1 = new QGridLayout;

 gridLayout1->addWidget(primaryColumnLabel,0,0,1,1);

 gridLayout1->addWidget(primaryColumnCombo,0,1,1,1);

 gridLayout1->addItem(spacerItem1,0,2,1,1);

 gridLayout1->addWidget(primaryOrderLabel,1,0,1,1);

 gridLayout1->addWidget(primaryOrderCombo,1,1,1,2);

 primaryGroupBox->setLayout(gridLayout1);

 spacerItem2 = new QSpacerItem(20, 0, QSizePolicy::Minimum,QSizePolicy::Expanding);

 secondaryGroupBox = new QGroupBox(tr("&Secondary Key"));

 secondaryColumnLabel = new QLabel(tr("Column:"));

 secondaryColumnCombo = new QComboBox;

 secondaryColumnCombo->addItem(tr("None"));

 spacerItem3 = new QSpacerItem(20,20,QSizePolicy::Minimum,QSizePolicy::Expanding);

 secondaryOrderLabel = new QLabel(tr("Order:"));

 secondaryOrderCombo = new QComboBox;

 secondaryOrderCombo->addItem(tr("Ascending"));

 secondaryOrderCombo->addItem(tr("Descending"));

 gridLayout2 = new QGridLayout;

 gridLayout2->addWidget(secondaryColumnLabel,0,0,1,1);//前两个数字代表起始位置，后两个代表长度和高度

 gridLayout2->addWidget(secondaryColumnCombo,0,1,1,1);

 gridLayout2->addItem(spacerItem3,0,2,1,1);

 gridLayout2->addWidget(secondaryOrderLabel,1,0,1,1);

 gridLayout2->addWidget(secondaryOrderCombo,1,1,1,2);

 secondaryGroupBox->setLayout(gridLayout2);

 tertiaryGroupBox = new QGroupBox(tr("&Tertiary Key"));

 tertiaryColumnLabel = new QLabel(tr("Column:"));

 tertiaryColumnCombo = new QComboBox;

 tertiaryColumnCombo->addItem(tr("None"));

 spacerItem4 = new QSpacerItem(20,20,QSizePolicy::Minimum,QSizePolicy::Expanding);

 tertiaryOrderLabel = new QLabel(tr("Order:"));

 tertiaryOrderCombo = new QComboBox;

 tertiaryOrderCombo->addItem(tr("Ascending"));

 tertiaryOrderCombo->addItem(tr("Descending"));

 gridLayout3 = new QGridLayout;

 gridLayout3->addWidget(tertiaryColumnLabel,0,0,1,1);

 gridLayout3->addWidget(tertiaryColumnCombo,0,1,1,1);

 gridLayout3->addItem(spacerItem4,0,2,1,1);

 gridLayout3->addWidget(tertiaryOrderLabel,1,0,1,1);

 gridLayout3->addWidget(tertiaryOrderCombo,1,1,1,2);

 tertiaryGroupBox->setLayout(gridLayout3);

 gridLayout = new QGridLayout; //窗口总的布局

 gridLayout->addLayout(vboxLayout,0,1,2,1);

 gridLayout->addWidget(primaryGroupBox,0,0,1,1);

 gridLayout->addItem(spacerItem2, 1, 0, 1, 1);

 gridLayout->addWidget(secondaryGroupBox, 2, 0, 1, 1);

 gridLayout->addWidget(tertiaryGroupBox, 3, 0, 1, 1);

 setLayout(gridLayout);

 QWidget::setTabOrder(primaryColumnCombo, primaryOrderCombo);//设置键的顺序

 QWidget::setTabOrder(primaryOrderCombo, secondaryColumnCombo);

 QWidget::setTabOrder(secondaryColumnCombo, secondaryOrderCombo);

 QWidget::setTabOrder(secondaryOrderCombo, tertiaryColumnCombo);

 QWidget::setTabOrder(tertiaryColumnCombo, tertiaryOrderCombo);

 QWidget::setTabOrder(tertiaryOrderCombo, okButton);

 QWidget::setTabOrder(okButton, cancelButton);

 QWidget::setTabOrder(cancelButton, moreButton);

 QObject::connect(moreButton, SIGNAL(toggled(bool)), secondaryGroupBox, SLOT(setVisible(bool)));

 QObject::connect(moreButton, SIGNAL(toggled(bool)), tertiaryGroupBox, SLOT(setVisible(bool)));

 QObject::connect(okButton,SIGNAL(clicked()),this,SLOT(accept()));

 QObject::connect(cancelButton,SIGNAL(clicked()),this,SLOT(reject()));

 QMetaObject::connectSlotsByName(this); //on_objectName_slot()

 secondaryGroupBox->hide();

 tertiaryGroupBox->hide();

 layout()->setSizeConstraint(QLayout::SetFixedSize); //设置布局大小的原则

 setColumnRange('A','Z');

}

void SortDialog::setColumnRange(QChar first,QChar last)

{

 primaryColumnCombo->clear();

 secondaryColumnCombo->clear();

 tertiaryColumnCombo->clear();

 secondaryColumnCombo->addItem(tr("None"));

 tertiaryColumnCombo->addItem(tr("None"));

 primaryColumnCombo->setMinimumSize(secondaryColumnCombo->sizeHint()); //同步大小

 QChar ch = first;

 while(ch <= last)

 {

 primaryColumnCombo->addItem(QString(ch));

 secondaryColumnCombo->addItem(QString(ch));

 tertiaryColumnCombo->addItem(QString(ch));

 ch = ch.unicode() + 1;  //这个函数会改变ch的值，因为这个函数用地址进行运算

 }

}

主函数：

#include <QtGui/QApplication>

#include "dialog.h"

int main(int argc,char *argv[])

{

 QApplication app(argc,argv);

 SortDialog *dialog = new SortDialog;

 dialog->setColumnRange('C','F');//设置范围为C到F

 dialog->show();

 return app.exec();

}

别人的代码，自己加了一些注释，给出了一些解释。。。不喜勿喷...