深入理解Qt 初始项目代码

#include "mywidget.h"

#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MyWidget w;
    w.show();
    return a.exec();
}

#ifndef MYWIDGET_H
#define MYWIDGET_H

#include <QWidget>

QT_BEGIN_NAMESPACE
namespace Ui { class MyWidget; }
QT_END_NAMESPACE

class MyWidget : public QWidget//继承父类
{
    Q_OBJECT//宏替换

public:
    MyWidget(QWidget *parent = nullptr);
    ~MyWidget();

private:
    Ui::MyWidget *ui;
};
#endif // MYWIDGET_H

QT_BEGIN_NAMESPACE
namespace Ui { class MyWidget; }
QT_END_NAMESPACE

#include "mywidget.h"//创建项目生成的头文件
#include "ui_mywidget.h"//form file被qmake生成的头文件

MyWidget::MyWidget(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::MyWidget)
{
    ui->setupUi(this);//把form file生成的界面和当前widget关联起来
}

MyWidget::~MyWidget()
{
    delete ui;
}

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>MyWidget</class>
 <widget class="QWidget" name="MyWidget">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>800</width>
    <height>600</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>MyWidget</string>
  </property>
 </widget>
 <resources/>
 <connections/>
</ui>

QT       += core gui

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

CONFIG += c++11

# The following define makes your compiler emit warnings if you use
# any Qt feature that has been marked deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS

# You can also make your code fail to compile if it uses deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0

SOURCES += \
    main.cpp \
    mywidget.cpp

HEADERS += \
    mywidget.h

FORMS += \
    mywidget.ui

# Default rules for deployment.
qnx: target.path = /tmp/$${TARGET}/bin
else: unix:!android: target.path = /opt/$${TARGET}/bin
!isEmpty(target.path): INSTALLS += target

/********************************************************************************
** Form generated from reading UI file 'mywidget.ui'
**
** Created by: Qt User Interface Compiler version 5.14.0
**
** WARNING! All changes made in this file will be lost when recompiling UI file!
********************************************************************************/

#ifndef UI_MYWIDGET_H
#define UI_MYWIDGET_H

#include <QtCore/QVariant>
#include <QtWidgets/QApplication>
#include <QtWidgets/QWidget>

QT_BEGIN_NAMESPACE

class Ui_MyWidget
{
public:

    void setupUi(QWidget *MyWidget)
    {
        if (MyWidget->objectName().isEmpty())
            MyWidget->setObjectName(QString::fromUtf8("MyWidget"));
        MyWidget->resize(800, 600);

        retranslateUi(MyWidget);

        QMetaObject::connectSlotsByName(MyWidget);
    } // setupUi

    void retranslateUi(QWidget *MyWidget)
    {
        MyWidget->setWindowTitle(QCoreApplication::translate("MyWidget", "MyWidget", nullptr));
    } // retranslateUi

};

namespace Ui {
    class MyWidget: public Ui_MyWidget {};
} // namespace Ui

QT_END_NAMESPACE

#endif // UI_MYWIDGET_H