QT learning 21 standard dialog box in QT (Part 2)

Qt Study 21 Qt Standard dialog boxes in （ Next ）

Font dialog

• Qt Provided in predefined Font dialog box QFontDialog class
• QFontDialog Class is used to provide Dialog box part for selecting font

• How to use the font dialog

//  Construct font dialog object 
QFontDialog dlg(this);
//  Set the relevant properties of the font dialog 
dlg.setWindowTitle("Font Editor");
dlg.setCurrentFont(QFont("Courier New", 10, QFont::Bold));	//  Initial font 
if (dlg.exec() == QFontDialog::Accepted) {
    
    qDebug() << dlg.selectedFont();
}

• QFontDialog Utility functions in
  • QFontDialog::getFont

Progress dialog

• Qt Provided in predefined Progress dialog box QProgressDialog class
• QProgressDialog Class used Show progress information
• QProgressDialog Class used Occasions that require users to wait

• How to use the progress dialog

//  Construction progress dialog object 
QProgressDialog dlg(this);
//  Set the relevant properties of the progress dialog 
dlg.setWindowTitle("Updating...");
dlg.setLabelText("Downloading from server...");
dlg.setMinimum(0);		//  Set the minimum progress value 
dlg.setMaximum(1000);	//  Set the maximum progress value 
dlg.exec();

Code experiments

#ifndef WIDGET_H
#define WIDGET_H

#include <QWidget>
#include <QPushButton>

class Widget : public QWidget
{
    
    Q_OBJECT
private:
    QPushButton FontDialogBtn;
    QPushButton ProgressDialogBtn;
private slots:
    void FontDialogBtn_Clicked();
    void ProgressDialogBtn_Clicked();
public:
    Widget(QWidget *parent = 0);
    ~Widget();
};

#endif // WIDGET_H

#include "Widget.h"
#include <QFontDialog>
#include <QProgressDialog>
#include <QDebug>

Widget::Widget(QWidget *parent)
    : QWidget(parent), FontDialogBtn(this), ProgressDialogBtn(this)
{
    
    FontDialogBtn.setText("Font Dialog");
    FontDialogBtn.move(20, 20);
    FontDialogBtn.resize(160, 30);

    ProgressDialogBtn.setText("Progress Dialog");
    ProgressDialogBtn.move(20, 70);
    ProgressDialogBtn.resize(160, 30);

    resize(200, 120);
    setFixedSize(200, 120);

    connect(&FontDialogBtn, SIGNAL(clicked()), this, SLOT(FontDialogBtn_Clicked()));
    connect(&ProgressDialogBtn, SIGNAL(clicked()), this, SLOT(ProgressDialogBtn_Clicked()));
}

Widget::~Widget()
{
    

}

void Widget::FontDialogBtn_Clicked()
{
    
    QFontDialog dlg(this);

    dlg.setWindowTitle("Font Dialog Test");
    dlg.setCurrentFont(QFont("Courier New", 10, QFont::Normal));
    if (dlg.exec() == QFontDialog::Accepted) {
    
        qDebug() << dlg.selectedFont();
    }
    //  Simple usage 
    bool ok;
    QFont font= QFont("Courier New", 10, QFont::Normal);
    font = QFontDialog::getFont(&ok, font, this);
    qDebug() << font;
}

void Widget::ProgressDialogBtn_Clicked()
{
    
    QProgressDialog dlg(this);

    dlg.setWindowTitle("Updating...");
    dlg.setLabelText("Downloading update from server...");
    dlg.setMinimum(0);
    dlg.setMaximum(100);
    dlg.setValue(35);
    // create a new thread
    dlg.exec();
}

#include "Widget.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    
    QApplication a(argc, argv);
    Widget w;
    w.show();

    return a.exec();
}

Summary

• Qt In the standard dialog box Design patterns
  • GUI Interface Component generation Data objects
  • Business logic Other objects in use Data objects
  • GUI Interface And Business logic adopt Data objects Connect