dialog box-qdialog

dialog box provides a convenient way for users to interact with the application, such as system options, font settings, etc.

Modal dialog box: The modal dialog box does not disappear before the user can interact with other windows of the same application, knowing that the dialog box is closed.

Customize dialog box

Logindlg.h

#ifndef Logindlg_h

#define Logindlg_h

#include <QDialog>

The purpose of this code is to tell the compiler that the Qlineedit class already exists

Class Qlineedit;   Only pointers to Qlineedit objects are used in the header file of Class Clogindlg, so the GCC compiler does not need to know the definition of the Qlineedit class when compiling the header file

Class Clogindlg:public Qdialog   //Custom class inheritance Qdialog

{

    Q_object            //The function of this macro is to start some features of the QT meta-object (such as supporting signals and slots), which must be placed in the private area of the class definition

Public

    Clogindlg (qwidget* =0);  is a constructor that specifies a default value of NULL for a parameter that points to Qwidget

    The parameter defines the parent widget for the custom dialog box object, and the default value of NULL means that the custom dialog box does not have a parent widget

Public Slots:

    virtual void accept ();

Private

    Qlineedit *usrlineedit;

    Qlineedit *pwdlineedit;

};

#endif//Logindlg_h

Logindlg.cpp
#include <QtGui/QtGui>

#include "Logindlg.h"

Clogindlg::clogindlg (Qwidget *parent)

    : Qdialog (parent)

{

    Qlabel *usrlabel=new Qlabel (tr ("User name:"));

    Qlabel *pwdlabel=new Qlabel (tr ("Password:"));

    Usrlineedit=new Qlineedit;

    Pwdlineedit=new Qlineedit;

    Pwdlineedit->setechomode (qlineedit::P assword);

    Qgridlayout *gridlayout=new qgridlayout;

    Gridlayout->addwidget (usrlabel,0,0,1,1);

    Gridlayout->addwidget (usrlineedit,0,1,1,3);

    Gridlayout->addwidget (pwdlabel,1,0,1,1);

    Gridlayout->addwidget (pwdlineedit,1,1,1,3);

    Qpushbutton *okbtn=new Qpushbutton (tr ("OK"));

    Qpushbutton *cancelbtn=new Qpushbutton (tr ("Cancel"));

    Qhboxlayout *btnlayout=new qhboxlayout;

    Btnlayout->setspacing (60);

    Btnlayout->addwidget (OKBTN);

    Btnlayout->addwidget (CANCELBTN);

    Qvboxlayout *dlglayout=new qvboxlayout;

    Dlglayout->setmargin (+);             Set the internal subassembly distance from the layout manager boundary to 40

    Dlglayout->addlayout (gridLayout);

    Dlglayout->addstretch (+);    Adding a size of 40 stretch,stretch between vertical layout managers can be scaled up and down

    Dlglayout->addlayout (btnlayout);

    SetLayout (dlglayout);

    Connect (okbtn,signal (clicked ()), This,slot (Accept ()));

    Connect (cancelbtn,signal (clicked ()), This,slot (Reject ())); Reject () hides the login dialog and sets the return code of the dialog box to qdialog::rejected, where the dialog closes and the slot function qdialog::exec () That launches the dialog box returns qdialog::rejected.

    Setwindowtitle (TR ("Landing"));

    Resize (300,200);  The size of the Reset dialog box is (300,200), which is 300 and the width is 200.

}

void Clogindlg::accept ()

{

    if (Usrlineedit->text (). Trimmed () ==tr ("admin")

    &&pwdlineedit->text (). Trimmed () ==tr ("admin"))

    {

        Qdialog::accept ();  If the user enters all correctly, calls the qdialog::accept () slot function in the parent class, the function closes the modal dialog box, the setting dialog runs as qdialog::accepted, and sends the qdialog::finished (int Result) signal.

    }

    Else

    {

        Create and display a modal warning window

        Qmessagebox::warning (This,

                             TR ("Warning"),

                             TR ("User name or password is wrong!"),

                             Qmessagebox::yes);

        Usrlineedit->setfocus ();   Position the cursor to an edit box object

    }

}
Main.cpp
#include <QtGui>

#include "Logindlg.h"

int main (int argc,char **argv)

{

    Qapplication A (ARGC,ARGV);

    QTEXTCODEC::SETCODECFORTR (Qtextcodec::codecforname ("Utf-8"));

    Qtranslator Translator;   The Qtranslator class provides support for internationalization of text output

    {        //braces are used to destroy the stack objects that are no longer in use in time

        Qstringlist environment=qprocess::systemenvironment ();   Get environment variables for a process

        QString str;

        BOOL Bfinded=false;    Defines an identifier for a lookup result

        foreach (str,environment)  //Find a string that begins with "qtdir=" in the list of obtained environment variables

        {

            if (Str.startswith ("qtdir="))

            {

                Bfinded=true;

                Break

            }

        }

        if (bfinded)   //The function of this segment of code is to install the translator for the application

        {

            Str=str.mid (6);  Use the mid () function to get the value of the environment variable, that is, the installation path of QT

            The following statement is equivalent to calling the Qtranslator:;load ("Qt_zh_cn", "$QTDIR/translations/");

            Bfinded=translator.load ("Qt_" +qlocale::system (). Name (),   //is a translation file that loads QT

                                    Str.append ("/translations/"));

            if (bfinded)

                Qapp->installtranslator (&translator);

            Else

                Qdebug () <<qobject::tr ("No Support Center for QT internationalization translation files!");

        }

        Else

        {

            Qdebug () <<qobject::tr ("must set QTDIR environment variable!");

            Exit (1);

        }

    }

    Clogindlg Dlg;

    return Dlg.exec ();

}

Examples of advanced applications of Qmessagebox

Qmessagebox box;

Box.setwindowtitle (tr ("warning");

Box.seticon (qmessagebox::warning);

Box.settext (TR ("Program installation error, exit?");

Box.setstandardbuttons (Qmessagebox::yes

| Qmessagebox::no);

Box.setdetailedtext (TR ("see if the installation media is damaged.) ");

Switch (box.exec ())

{

Case Qmessagebox::yes:

Proceed to the next

Break

Case Qmessagebox::no:

Proceed to the next

Break

Default

Make default processing

Break

}

Qt built-in dialog box

dialog box-qdialog