C/C++Qt自定义Dialog对话框组件应用案例详解

#include "dialog.h"
#include "ui_dialog.h"

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

// 用于MainWindow获取编辑框中的数据
QString Dialog::GetValue()
{
    return ui->lineEdit->text();
}

// 用于设置当前编辑框中的数据为MainWindow
// https://www.cnblogs.com/lyshark
void Dialog::SetValue(QString x)
{
    ui->lineEdit->setText(x);
}

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

void Dialog::on_BtnOk_clicked()
{

}
void Dialog::on_BtnCancel_clicked()
{

}

#include "mainwindow.h"
#include "ui_mainwindow.h"

#include "dialog.h"
#include <iostream>
#include <QDialog>

MainWindow::MainWindow(QWidget *parent) :QMainWindow(parent),ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    ui->lineEdit->setEnabled(false);
    ui->lineEdit->setText("hello lyshark");
}

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

// By: LyShark
// https://www.cnblogs.com/lyshark
// 按钮点击后执行
void MainWindow::on_pushButton_clicked()
{
    // 创建模态对话框
    Dialog *ptr = new Dialog(this);                                 // 创建一个对话框
    Qt::WindowFlags flags = ptr->windowFlags();                     // 需要获取返回值
    ptr->setWindowFlags(flags | Qt::MSWindowsFixedSizeDialogHint);  // 设置对话框固定大小

    // 读取MainWindows参数并设置到Dialog
    QString item = ui->lineEdit->text();
    ptr->SetValue(item);

    int ref = ptr->exec();             // 以模态方式显示对话框
    if (ref==QDialog::Accepted)        // OK键被按下,对话框关闭
    {
        // 当BtnOk被按下时,则设置对话框中的数据
        QString the_value = ptr->GetValue();
        std::cout << "value = " << the_value.toStdString().data() << std::endl;
        ui->lineEdit->setText(the_value);
    }

    // 删除释放对话框句柄
    delete ptr;
}

#ifndef DIALOG_H
#define DIALOG_H

#include <QDialog>

namespace Ui {
class Dialog;
}

class Dialog : public QDialog
{
    Q_OBJECT

public:
    explicit Dialog(QWidget *parent = nullptr);
    ~Dialog();

// By: LyShark
// https://www.cnblogs.com/lyshark
private:
    Ui::Dialog *ui;


// 定义信号(信号只需声明无需实现)
signals:
    void sendText(QString str);

private slots:
    void on_pushButton_clicked();
};

#endif // DIALOG_H

#include "dialog.h"
#include "ui_dialog.h"

// By: LyShark
// https://www.cnblogs.com/lyshark
Dialog::Dialog(QWidget *parent) :QDialog(parent),ui(new Ui::Dialog)
{
    ui->setupUi(this);
    connect(ui->pushButton, SIGNAL(clicked()), this, SLOT(onBtnClick()));
}

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

// 发送信号到MainWindow
void Dialog::on_pushButton_clicked()
{
    QString send_data = ui->lineEdit->text();
    emit sendText(send_data);
}

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = nullptr);
    ~MainWindow();

// By: LyShark
// https://www.cnblogs.com/lyshark
private slots:
    // 定义槽函数
    void receiveMsg(QString str);
    void on_pushButton_clicked();

private:
    Ui::MainWindow *ui;
};

#endif // MAINWINDOW_H

#include "mainwindow.h"
#include "ui_mainwindow.h"

#include "dialog.h"
#include <QDialog>

// By: LyShark
// https://www.cnblogs.com/lyshark
MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent),ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    ui->lineEdit->setEnabled(false);
}

// 接收信号并设置到LineEdit上
void MainWindow::receiveMsg(QString str)
{
    ui->lineEdit->setText(str);
}

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

void MainWindow::on_pushButton_clicked()
{
    Dialog *subwindow = new Dialog(this);
    // 当收到sendText信号时使用receiveMsg槽函数处理
    connect(subwindow, SIGNAL(sendText(QString)), this, SLOT(receiveMsg(QString)));
    subwindow->show();
}