Qt5 UI内嵌UI的实现&相互通信的方法

主要用到QStackedWidget和友元类声明，废话不多说直接上代码。

工程架构：

1.mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>

class Form;

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();
    friend class Form;
    class Form *form;

private slots:
    void on_pushButton_clicked();

private:
    Ui::MainWindow *ui;
};

#endif // MAINWINDOW_H

2.mainwindow.ui

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>MainWindow</class>
 <widget class="QMainWindow" name="MainWindow">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>561</width>
    <height>507</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>MainWindow</string>
  </property>
  <widget class="QWidget" name="centralWidget">
   <layout class="QVBoxLayout" name="verticalLayout">
    <property name="spacing">
     <number>5</number>
    </property>
    <property name="leftMargin">
     <number>5</number>
    </property>
    <property name="topMargin">
     <number>5</number>
    </property>
    <property name="rightMargin">
     <number>5</number>
    </property>
    <property name="bottomMargin">
     <number>5</number>
    </property>
    <item>
     <layout class="QHBoxLayout" name="horizontalLayout">
      <item>
       <widget class="QLineEdit" name="lineEdit">
        <property name="placeholderText">
         <string>Main Text Edit</string>
        </property>
       </widget>
      </item>
      <item>
       <widget class="QToolButton" name="toolButton">
        <property name="text">
         <string>...</string>
        </property>
       </widget>
      </item>
     </layout>
    </item>
    <item>
     <widget class="QStackedWidget" name="stackedWidget">
      <widget class="QWidget" name="page"/>
      <widget class="QWidget" name="page_2"/>
     </widget>
    </item>
    <item>
     <layout class="QHBoxLayout" name="horizontalLayout_2">
      <item>
       <spacer name="horizontalSpacer">
        <property name="orientation">
         <enum>Qt::Horizontal</enum>
        </property>
        <property name="sizeHint" stdset="0">
         <size>
          <width>40</width>
          <height>20</height>
         </size>
        </property>
       </spacer>
      </item>
      <item>
       <widget class="QPushButton" name="pushButton">
        <property name="text">
         <string>Main Btn</string>
        </property>
       </widget>
      </item>
     </layout>
    </item>
   </layout>
  </widget>
  <widget class="QMenuBar" name="menuBar">
   <property name="geometry">
    <rect>
     <x>0</x>
     <y>0</y>
     <width>561</width>
     <height>26</height>
    </rect>
   </property>
  </widget>
  <widget class="QStatusBar" name="statusBar"/>
 </widget>
 <layoutdefault spacing="6" margin="11"/>
 <resources/>
 <connections/>
</ui>

3.mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include "form.h"
#include "ui_form.h"

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    form = new Form();
    form->mainUi = this;

    ui->stackedWidget->addWidget(form);
    ui->stackedWidget->setWindowTitle("Form");
    ui->stackedWidget->setCurrentWidget(form);
}

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

void MainWindow::on_pushButton_clicked()
{
    form->ui->lineEdit->setText("99999999");
}

4.form.h

#ifndef FORM_H
#define FORM_H

#include <QWidget>

class MainWindow;

namespace Ui {
class Form;
}

class Form : public QWidget
{
    Q_OBJECT

public:
    explicit Form(QWidget *parent = 0);
    ~Form();
    friend class MainWindow;
    class MainWindow *mainUi;
    void addText();

private slots:
    void on_pushButton_clicked();

private:
    Ui::Form *ui;
};

#endif // FORM_H

5.form.cpp

#include "form.h"
#include "ui_form.h"
#include "mainwindow.h"
#include "ui_mainwindow.h"

Form::Form(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Form)
{
    ui->setupUi(this);
}

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

void Form::on_pushButton_clicked()
{
    mainUi->ui->lineEdit->setText("0000000");
}

6.form.ui

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>Form</class>
 <widget class="QWidget" name="Form">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>890</width>
    <height>671</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>Form</string>
  </property>
  <layout class="QVBoxLayout" name="verticalLayout">
   <item>
    <layout class="QHBoxLayout" name="horizontalLayout_2">
     <item>
      <widget class="QLineEdit" name="lineEdit">
       <property name="placeholderText">
        <string>From Text Edit</string>
       </property>
      </widget>
     </item>
     <item>
      <widget class="QToolButton" name="toolButton">
       <property name="text">
        <string>...</string>
       </property>
      </widget>
     </item>
    </layout>
   </item>
   <item>
    <widget class="QListView" name="listView"/>
   </item>
   <item>
    <layout class="QHBoxLayout" name="horizontalLayout">
     <item>
      <widget class="QLineEdit" name="lineEdit_2"/>
     </item>
     <item>
      <widget class="QToolButton" name="toolButton_2">
       <property name="text">
        <string>...</string>
       </property>
      </widget>
     </item>
    </layout>
   </item>
   <item>
    <layout class="QHBoxLayout" name="horizontalLayout_3">
     <item>
      <spacer name="horizontalSpacer">
       <property name="orientation">
        <enum>Qt::Horizontal</enum>
       </property>
       <property name="sizeHint" stdset="0">
        <size>
         <width>40</width>
         <height>20</height>
        </size>
       </property>
      </spacer>
     </item>
     <item>
      <widget class="QPushButton" name="pushButton">
       <property name="text">
        <string>From Btn</string>
       </property>
      </widget>
     </item>
    </layout>
   </item>
  </layout>
 </widget>
 <resources/>
 <connections/>
</ui>

7.main.cpp

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

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

    return a.exec();
}

8.UiInUiTest.pro

#-------------------------------------------------
#
# Project created by QtCreator 2018-07-01T13:51:03
#
#-------------------------------------------------

QT       += core gui

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = UiInUiTest
TEMPLATE = app

# The following define makes your compiler emit warnings if you use
# any feature of Qt which has been marked as 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 you use 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 \
        mainwindow.cpp \
    form.cpp

HEADERS += \
        mainwindow.h \
    form.h

FORMS += \
        mainwindow.ui \
    form.ui

完整工程代码：https://download.youkuaiyun.com/download/mccoy39082/10511888