class FPFileButton {
public:
    GFile *file;
    shared_ptr<EditArea> ea;
    GtkButton *Button;
    char *FileAbsoPath;
    char *FileRelePath;
    char *FileName;

    void init(GFile *FileGFile,int level);// the level of Root folder is 0
    void Open();
};

Use init to apply properties in the class.

GtkButton *Button is the button you see in the panel. If the button is clicked, FileButtonClick()(the function is not in the class) will be called, and run the Open() .