【qt学习003】渐入佳境——各种标准消息框的使用

// messagebox.h

#ifndef MESSAGEBOX_H

#define MESSAGEBOX_H

#include <QPushButton>

#include <QLabel>

#include <QGridLayout>

#include <QMessageBox>

#include <QDialog>

class
messagebox: public
QDialog // 必须加上public QDialog，因为要从QDialog类中继承很多内容

{

    Q_OBJECT

public:

    messagebox();

    ~messagebox();

public:

    QLabel *label;

    QPushButton *quest;

    QPushButton *info;

    QPushButton *warn;

    QPushButton *crtcal;

    QPushButton *about;

    QPushButton *aboutQt;

    QPushButton *custom;

    QGridLayout *layout;

private
slots:

    void
slotQuestion();

    void
slotInformation();

    void
slotWarning();

    void
slotCritical();

    void
slotAbout();

    void
slotAboutQt();

    void
slotCustom();

};

#endif // MESSAGEBOX_H

// messagebox.cpp

#include "messagebox.h"

messagebox::messagebox()

{

    // 创建元素

    label = new
QLabel;

    label->setText(tr("About Qt Message Box"));

    quest = new
QPushButton;

    quest->setText(tr("Question"));

    info = new
QPushButton;

    info->setText(tr("Information"));

    warn = new
QPushButton;

    warn->setText(tr("Warning"));

    crtcal = new
QPushButton;

    crtcal->setText(tr("Critical"));

    about = new
QPushButton;

    about->setText(tr("About"));

    aboutQt = new
QPushButton;

    aboutQt->setText(tr("About Qt"));

    custom = new
QPushButton;

    custom->setText(tr("custom"));

    layout = new
QGridLayout(this); // 最初没有加上this，显示只有一个空白的方框，下列元素没有显示在其中。

    // 布局

    layout->addWidget(label, 0, 0);

    layout->addWidget(quest, 0 , 1);

    layout->addWidget(info, 1, 1);

    layout->addWidget(warn, 1, 0);

    layout->addWidget(crtcal, 2, 1);

    layout->addWidget(about, 2, 0);

    layout->addWidget(aboutQt, 3, 1);

    layout->addWidget(custom, 3, 0);

    // 连接槽

    connect(quest, SIGNAL(clicked()), this, SLOT(slotQuestion()) );

    connect(about, SIGNAL(clicked()), this, SLOT(slotAbout()));

    connect(aboutQt, SIGNAL(clicked()), this, SLOT(slotAboutQt()));

    connect(info, SIGNAL(clicked()), this, SLOT(slotInformation()));

    connect(warn, SIGNAL(clicked()), this, SLOT(slotWarning()));

    connect(crtcal, SIGNAL(clicked()), this, SLOT(slotCritical()));

    connect(custom, SIGNAL(clicked()), this, SLOT(slotCustom()));

}

messagebox::~messagebox()

{

    delete
label;

    delete
layout;

    delete
quest;

    delete
about;

    delete
aboutQt;

    delete
info;

    delete
warn;

    delete
crtcal;

    delete
custom;

}

void
messagebox::slotQuestion()

{

    switch(QMessageBox::question(this, "Question",tr("It‘s end of document, search from begin?"),

                                 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
; // 这句有没有，并无影响

}

void
messagebox::slotInformation()

{

    QMessageBox::information(this, "Information", tr("anything you want tell user"));

    return
;

}

void
messagebox::slotWarning()

{

    switch(QMessageBox::warning(this, "Warning",

                                tr("Save changes to document?"),

                                QMessageBox::Save|QMessageBox::Discard|QMessageBox::Cancel,

                                QMessageBox::Save))

    {

    case
QMessageBox::Save:

        label->setText("Warning button /Save");

        break;

    case
QMessageBox::Discard:

        label->setText("Warning button/ Discard");

        break;

    case
QMessageBox::Cancel:

        label->setText("Warning button/ Cancel");

        break;

    default:

        break;

    }

    return
;

}

void
messagebox::slotCritical()

{

    QMessageBox::critical(this, "Information", tr("tell user a critical error"));

    label->setText("Critical MessageBox");

    return;

}

void
messagebox::slotAbout()

{

    QMessageBox::about(this, "About", tr("Message box example"));

    label->setText("About MessageBox");

    return
;

}

void
messagebox::slotAboutQt()

{

    QMessageBox::aboutQt(this, "About Qttttttt"); // 设置消息框名称

    label->setText("About Qt MessageBox");

    return
;

}

void
messagebox::slotCustom()

{

    QMessageBox customMsgBox; // 用鼠标点QMessageBOx, 然后按F1， 将出现QMessageBox的内部说明文档

    customMsgBox.setWindowTitle("Custom message box");

    QPushButton *lockButton = customMsgBox.addButton(tr("Lock"),

                                                     QMessageBox::ActionRole);

    QPushButton *unlockButton = customMsgBox.addButton(tr("Unlock"),

                                                       QMessageBox::ActionRole);

    QPushButton *cancelButton = customMsgBox.addButton(

                      QMessageBox::Cancel);

    customMsgBox.setIconPixmap(QPixmap(""));

    customMsgBox.setText("This is a custom message box");

    customMsgBox.exec();

    if(customMsgBox.clickedButton() == lockButton)

        label->setText("Custom MessageBox /Lock");

    if(customMsgBox.clickedButton() == unlockButton)

        label->setText("Custom MessageBox/ Unlock");

    if(customMsgBox.clickedButton() == cancelButton)

        label->setText("Custom MessageBox/Cancel");

    return
;

}

// main.cpp

#include <QApplication>

#include <QPushButton>

#include <QLabel>

#include "standarddialogs.h"

#include "geometry.h"

#include "inputdialog.h"

#include "messagebox.h"

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

{

    QApplication a(argc, argv);

    // StandardDialogs ct;

    // ct.show();

    // QPushButton b("Hello World!");

    // b.show();

    // QObject::connect(&b, SIGNAL(clicked()), &a, SLOT(quit()));

    // Geometry my;

    // my.show();

   // InputDlg person;

    // person.show();

    messagebox msgb;

    msgb.show();

    return
a.exec();

}