QT：基本控件的使用1

这个是书上的一个示例，有需要的可以去看看书，书上的案例挺全的。
效果展示：
1、选择文本框实例，可以打开文件目录，并将文件路径显示在文本框中；
2、点击颜色标准对话框实例，可打开一个Color插件，选择颜色，实现文本框的填充；
3、点击字体标准对话框按钮，打开字体插件，转换字体大小，可调整文本框中的“Hello World”；
4、点击标准输入对话框按钮，可查看信息科进行修改，如图2所示；
5、点击用户自定义消息对话框实例，程序会弹出对话框，如图3所示；


图1：

图2：

图3：

代码部分：
dialog.cpp

#include "dialog.h"
#include<QFileDialog>
#include<QColorDialog>
#include<QPalette>
#include<QFontDialog>
#include<QMessageBox>

Dialog::Dialog(QWidget *parent)
    : QDialog(parent)
{
    setWindowTitle(tr("各种标准对话框的示例"));
    fileBtn = new QPushButton;
    fileBtn->setText(tr("文件标准对话框实例"));
    fileLineEdit = new QLineEdit;
    //fileLineEdit->setText();
    mainLayout = new QGridLayout(this);//布局设计
    mainLayout->addWidget(fileBtn,0,0);
    mainLayout->addWidget(fileLineEdit,0,1);
    connect(fileBtn,SIGNAL(clicked()),this,SLOT(showFile()));  //事件关联

    colorBtn = new QPushButton;
    colorBtn->setText(tr("颜色标准对话框实例"));
    colorFrame = new QFrame;
    colorFrame->setFrameShape(QFrame::Box);
    colorFrame->setAutoFillBackground(true);
    mainLayout->addWidget(colorBtn,1,0);
    mainLayout->addWidget(colorFrame,1,1);
    connect(colorBtn,SIGNAL(clicked()),this,SLOT(showColor()));

    fontBtn = new QPushButton;
    fontBtn->setText(tr("字体标准对话框实例"));
    fontLineEdit = new QLineEdit;
    fontLineEdit->setText(tr("Hello World"));
    mainLayout->addWidget(fontBtn,2,0);
    mainLayout->addWidget(fontLineEdit,2,1);
    connect(fontBtn,SIGNAL(clicked()),this,SLOT(showFont()));

    inputBtn = new QPushButton;
    inputBtn->setText(tr("标准输入对话框"));
    mainLayout->addWidget(inputBtn,3,0);
    connect(inputBtn,SIGNAL(clicked()),this,SLOT(showInputDlg()));

    MsgBtn = new QPushButton;
    MsgBtn->setText(tr("标准消息对话框实例"));
    mainLayout->addWidget(MsgBtn,3,1);
   connect(MsgBtn,SIGNAL(clicked()),this,SLOT(showMsgDlg()));

   CustomBtn = new QPushButton;
   CustomBtn->setText(tr("用户自定义消息对话框实例"));
   label  = new QLabel;
   label->setFrameStyle(QFrame::Panel | QFrame::Sunken);
   mainLayout->addWidget(CustomBtn,4,0);
   mainLayout->addWidget(label,4,1);
   connect(CustomBtn,SIGNAL(clicked()),this,SLOT(showCustomDlg()));


}

Dialog::~Dialog()
{

}
void Dialog::showFile()
{
    QString s=QFileDialog::getOpenFileName(this,"open file dialog","/","C++ files(*.cpp)::C files(*.c)::Head files(*.h)");
    fileLineEdit->setText(s);
}
void Dialog::showColor()
{
    QColor c = QColorDialog::getColor(Qt::blue);
    if(c.isValid())
    {
        colorFrame->setPalette(QPalette(c));
    }
}
void Dialog::showFont()
{
    bool ok;
    QFont f=QFontDialog::getFont(&ok);
    if(ok)
    {
        fontLineEdit->setFont(f);
    }
}
void Dialog::showInputDlg()
{
    inputDlg = new  InputDlg();
    inputDlg->show();

}
void Dialog::showMsgDlg()
{
    msgDlg = new MsgBoxDlg();
    msgDlg->show();
}
void Dialog::showCustomDlg()
{
    label->setText(tr("Custom massage box"));

    QMessageBox customMsgBox;
    customMsgBox.setWindowTitle(tr("用户自定义消息框"));

    QPushButton *yesBtn = customMsgBox.addButton("YES",QMessageBox::ActionRole);
     QPushButton *noBtn = customMsgBox.addButton("NO",QMessageBox::ActionRole);
      QPushButton *cancelBtn = customMsgBox.addButton(QMessageBox::Cancel);

      customMsgBox.setText(tr("这是一个自定义消息对话框"));
      customMsgBox.setIconPixmap(QPixmap("Qt.png"));//设置标题图标
      customMsgBox.exec();

      if(customMsgBox.clickedButton()==yesBtn)
          label->setText("Custom Message Box/Yes");
      if(customMsgBox.clickedButton()==noBtn)
          label->setText("Custom Message Box/no");
      if(customMsgBox.clickedButton()==cancelBtn)
          label->setText("Custom Message Box/no");

      return ;
}

inputdlg.cpp

#include "inputdlg.h"
#include<QInputDialog>
InputDlg::InputDlg(QWidget *parent) : QDialog(parent)
{
    setWindowTitle(tr("标准输入对话框实例"));

    nameLabel1 = new QLabel;
    nameLabel1->setText(tr("姓名:"));
    nameLabel2 = new QLabel;
    nameLabel2->setText(tr("张三"));
    nameLabel2->setFrameStyle(QFrame::Panel | QFrame::Sunken);
    nameBtn = new QPushButton;
    nameBtn ->setText(tr("修改姓名"));

    connect(nameBtn,SIGNAL(clicked()),this,SLOT(ChangeName()));

    sexLabel1 = new QLabel;
    sexLabel1->setText(tr("性别:"));
    sexLabel2 = new QLabel;
    sexLabel2->setText(tr("男"));
    sexLabel2->setFrameStyle(QFrame::Panel | QFrame::Sunken);
    sexBtn = new QPushButton;
    sexBtn->setText(tr("修改性别"));

    connect(sexBtn,SIGNAL(clicked()),this,SLOT(ChangeSex()));

    ageLabel1 = new QLabel;
    ageLabel1->setText(tr(" 年龄"));
    ageLabel2 = new QLabel;
    ageLabel2->setText(tr("22"));
    ageLabel2->setFrameStyle(QFrame::Panel | QFrame::Sunken);
    ageBtn = new QPushButton;
    ageBtn->setText(tr("修改年龄"));

    connect(ageBtn,SIGNAL(clicked()),this,SLOT(ChangeAge()));

    scoreLabel1 = new QLabel;
    scoreLabel1->setText(tr("成绩:"));
    scoreLabel2 = new QLabel;
    scoreLabel2->setText(tr("55"));
    scoreLabel2->setFrameStyle(QFrame::Panel | QFrame::Sunken);
    scoreBtn = new QPushButton;
    scoreBtn->setText(tr("修改成绩"));

    connect(scoreBtn,SIGNAL(clicked()),this,SLOT(ChangeScore()));

    mainLayout = new QGridLayout(this);
    mainLayout->addWidget(nameLabel1,0,0);
    mainLayout->addWidget(nameLabel2,0,1);
    mainLayout->addWidget(nameBtn,0,2);

    mainLayout->addWidget(sexLabel1,1,0);
    mainLayout->addWidget(sexLabel2,1,1);
    mainLayout->addWidget(sexBtn,1,2);

    mainLayout->addWidget(ageLabel1,2,0);
    mainLayout->addWidget(ageLabel2,2,1);
    mainLayout->addWidget(ageBtn,2,2);

    mainLayout->addWidget(scoreLabel1,3,0);
    mainLayout->addWidget(scoreLabel2,3,1);
    mainLayout->addWidget(scoreBtn,3,2);

    mainLayout->setMargin(15);//边框距离
    mainLayout->setSpacing(10);//空间间隔

}
void InputDlg::ChangeName()
{
    bool ok;
    //修改
    QString name =QInputDialog::getText(this,tr("标准字符串输入对话框"),tr("请输入姓名"),QLineEdit::Normal,nameLabel2->text());
    if(ok && !name.isEmpty())
    {
        nameLabel2->setText(name);
    }
}
void InputDlg::ChangeSex()
{
    QStringList SexItems;
    SexItems<<tr("男")<<tr("女");//只能输入男或女
    bool ok;
    //修改
    QString sex =QInputDialog::getItem(this,tr("标准条目选择对话框"),tr("请输入性别"),SexItems,0,false,&ok);
    if(ok && !sex.isEmpty())
    {
        sexLabel2->setText(sex);
    }
}

void InputDlg::ChangeAge()
{
    bool ok;
    //修改
    int age =QInputDialog::getInt(this,tr("标准Int输入对话框"),tr("请输入年龄"),ageLabel2->text().toInt(&ok),0,100,1,&ok);
    if(ok)
    {
        ageLabel2->setText(QString(tr("%1")).arg(age));
    }
}

void InputDlg::ChangeScore()
{
    bool ok;
    //修改
    double score =QInputDialog::getDouble(this,tr("标准double类型输入对话框"),tr("请输入分数"),scoreLabel2->text().toDouble(&ok),0,100,1,&ok);;
    if(ok )
    {
        scoreLabel2->setText(QString(tr("%1")).arg(score));
    }
}

msgboxdlg.cpp

#include "msgboxdlg.h"
#include<QMessageBox>
MsgBoxDlg::MsgBoxDlg(QWidget *parent) : QDialog(parent)
{
    setWindowTitle(tr("标准消息对话框的实例"));

    label = new QLabel;
    label->setText(tr("请选择一种消息对话框"));

    questionBtn = new QPushButton;
    questionBtn->setText(tr("QuestionMsg"));

    connect(questionBtn,SIGNAL(clicked()),this,SLOT(showQuestionMsg()));

    informationBtn = new QPushButton;
    informationBtn->setText(tr("InformationMsg"));

    connect(informationBtn,SIGNAL(clicked()),this,SLOT(showInformationMsg()));

    warningBtn = new QPushButton;
    warningBtn->setText(tr("WarningMsg"));

    connect(warningBtn,SIGNAL(clicked()),this,SLOT(showWarningMsg()));

    criticalBtn = new QPushButton;
    criticalBtn->setText(tr("CriticalMsg"));


    connect(criticalBtn,SIGNAL(clicked()),this,SLOT(showCriticalMsg()));


    aboutBtn = new QPushButton;
    aboutBtn->setText(tr("AboutMsg"));

    connect(aboutBtn,SIGNAL(clicked()),this,SLOT(showAboutMsg()));

    aboutQtBtn = new QPushButton;
    aboutQtBtn->setText(tr("AboutQtMsg"));

    connect(aboutQtBtn,SIGNAL(clicked()),this,SLOT(showAboutQtMsg()));

    //布局
    mainLayout = new QGridLayout(this);
    mainLayout->addWidget(label,0,0,1,2);
    mainLayout->addWidget(questionBtn,1,0);
    mainLayout->addWidget(informationBtn,1,1);
    mainLayout->addWidget(warningBtn,2,0);
    mainLayout->addWidget(criticalBtn,2,1);
    mainLayout->addWidget(aboutBtn,3,0);
    mainLayout->addWidget(aboutQtBtn,3,1);
}
void MsgBoxDlg::showQuestionMsg()
{
    label->setText(tr("Question Message Box"));
    switch(QMessageBox::question(this,tr("Question消息框"),
          tr("您现在已经修改完成，是否要结束程序？"),
          QMessageBox::Ok|QMessageBox::Cancel,QMessageBox::Ok))
    {
    case QMessageBox::Ok:
        label->setText("Question button/Ok");
        break;
    case QMessageBox::Cancel:
        label->setText("Question button/Cancel");
        break;
    default:
        break;
    }
    return;
}
void MsgBoxDlg::showInformationMsg()
{
    label->setText(tr("Information Message Box"));
    QMessageBox::information(this,tr("Information消息框"),
                             tr("这是Information消息框测试，欢迎您！"));
    return;
}
void MsgBoxDlg::showWarningMsg()
{
    label->setText(tr("Warning Message Box"));
    switch(QMessageBox::warning(this,tr("Warning消息框"),
         tr("您修改的内容还未保存，是否要保存对文档的修改？"),
         QMessageBox::Save|QMessageBox::Discard|QMessageBox::Cancel,
         QMessageBox::Save))
    {
    case QMessageBox::Save:
        label->setText(tr("Warning button/Save"));
        break;
    case QMessageBox::Discard:
        label->setText(tr("Warning button/Discard"));
        break;
    case QMessageBox::Cancel:
        label->setText(tr("Warning button/Cancel"));
        break;
    default:
        break;
    }
    return;
}
void MsgBoxDlg::showCriticalMsg()
{
    label->setText(tr("Critical Message Box"));
    QMessageBox::critical(this,tr("Critical消息框"),tr("这是一个Critical消息框测试！"));
    return;
}
void MsgBoxDlg::showAboutMsg()
{
    label->setText(tr("About Message Box"));
    QMessageBox::about(this,tr("About消息框"),tr("这是一个About消息框测试！"));
    return;
}
void MsgBoxDlg::showAboutQtMsg()
{
    label->setText(tr("About Qt Message Box"));
    QMessageBox::aboutQt(this,tr("About Qt消息框"));
    return;
}

源码链接：
https://download.youkuaiyun.com/download/zq9955/15116561