Question

我在尝试运行此应用程序时收到错误...错误消息是：

main.cpp（11）：错误：表达式必须具有类类型 int r = dialog.exec（）;而且我不确定为什么!!!

我正在使用qmake生成make文件...我已经将必要的文件添加到* .pro文件，因为Dialog是从QDialog继承的，我应该可以访问函数exec！

#include <QtGui>
#include <QDialog>
#include <QtUtil.h>
#include <Mathematics.h>
#include <Pair.h>
#include "View.h"

class QMesseageBox;
class QAction;
class QDialogButtonBox;
class QLabel;
class QLineEdit;
class QPushButton;
class QTextEdit;

class Dialog : public QDialog {
    Q_OBJECT
public:
    Dialog() {
        QHBoxLayout *layout = new QHBoxLayout;
        // prevent left vertical box from growing when main window resized
        layout->addStretch(1);

        QLabel*      lab_Layers = new QLabel(tr("Layers"));
        d_inline   = new QLineEdit;
        d_inline->setText("50");

        scene = new QGraphicsScene(0, 0, 500, 500);
        view  = new View;

        layout->addWidget(view);
        view->setScene(scene);

        QVBoxLayout *mainLayout = new QVBoxLayout;
        mainLayout->addLayout(layout);
        setLayout(mainLayout);
        setWindowTitle(tr("VI Smooth 0.4"));    
    }

private slots:
    // scroll the "after" window when "before" one is scrolled (so they
    // remain in sync)

private:
    QAction* exitAction;
    QtUtil qt;
    QLineEdit*   d_inline;
    QGraphicsScene* scene;
    QGraphicsView*  view;
};

主要班级

#include <QApplication>
#include <QMessageBox>
#include "Dialog.h"

int 
main(int argc, char **argv) {
    QApplication app(argc, argv);
      argv++;
    Dialog dialog();
//  dialog.showMaximized();
    int r = dialog.exec();
    return 0;
}

Answer 1

看起来应该是这样的。如果您创建了Dialog对象，则需要致电show()。您还需要在app.exec()中返回main()。

#include <QApplication>
#include <QMessageBox>
#include "Dialog.h"

int 
main(int argc, char **argv) {
    QApplication app(argc, argv);
      argv++;
    Dialog dialog;
    dialog.show()
    return app.exec(argc, argv);
}

执行自定义qdialog

1 个答案: