Qt界面编程：窗口传值方式

 1 //主窗口的.h文件，头文件和预处理机制已经去掉
 2 class MainWindow : public QMainWindow
 3 {
 4     Q_OBJECT
 5     
 6 public:
 7     explicit MainWindow(QWidget *parent = 0);
 8     ~MainWindow();
 9     
10 private slots:
11     void on_actionPopup_triggered();
12 
13 private:
14     Ui::MainWindow *ui;
15     QString name;    //declaration
16 };
17 //主窗口的cpp实现文件，其他同上
18 MainWindow::MainWindow(QWidget *parent) :
19     QMainWindow(parent),
20     ui(new Ui::MainWindow)
21 {
22     ui->setupUi(this);
23     name = "YES";   //initialization of member variable
24 }
25 
26 MainWindow::~MainWindow()
27 {
28     delete ui;
29 }
30 
31 void MainWindow::on_actionPopup_triggered()
32 {
33     Dialog myDlg(this);   //This is important
34     myDlg.exec();
35 }
36 //Dialog header
37 namespace Ui {
38 class Dialog;
39 }
40 
41 class Dialog : public QDialog
42 {
43     Q_OBJECT
44     
45 public:
46     explicit Dialog(QWidget *parent = 0);
47     ~Dialog();
48     
49 private slots:
50     void on_pushButton_test_clicked();
51 
52 private:
53     Ui::Dialog *ui;
54 };
55 //dialog implementation
56 Dialog::Dialog(QWidget *parent) :
57     QDialog(parent),
58     ui(new Ui::Dialog)
59 {
60     ui->setupUi(this);
61 }
62 
63 Dialog::~Dialog()
64 {
65     delete ui;
66 }
67 
68 void Dialog::on_pushButton_test_clicked()
69 {
70     MainWindow* ptr = (MainWindow*)parentWidget();  //conversion
71     ui->label->setText(ptr->name);
72 }