QT文件相关操作对话框、QT颜色选择相关操作对话框、QT字体相关操作对话框

 #ifndef DIALOG_H

    
 #define DIALOG_H
    
  
    
 #include<QPushButton>
    
 #include<QLineEdit>
    
 #include<QFileDialog>
    
 #include<QGridLayout>
    
 #include<QDialog>
    
 class MyDialog : public QDialog
    
 {
    
     Q_OBJECT
    
 public:
    
     MyDialog(QWidget *parent = 0);
    
  
    
 private slots:
    
     void showFile();
    
     void showColor();
    
     void showFont();
    
 private:
    
     //文件
    
     QPushButton *fileButton;
    
     QLineEdit *fileLineEdit;
    
     QGridLayout *layout;
    
     //色彩
    
     Q