chap2.1子类化QDialog
....................\Qdialog
....................\.......\Qdialog.pro
....................\.......\Qdialog.pro.user
....................\.......\finddialog.cpp
....................\.......\finddialog.h
....................\.......\main.cpp
....................\build-Qdialog-Desktop_Qt_5_7_0_MinGW_32bit-Debug
....................\................................................\.qmake.stash
....................\................................................\Makefile
....................\................................................\Makefile.Debug
....................\................................................\Makefile.Release
....................\................................................\debug
....................\................................................\.....\Qdialog.exe
....................\................................................\.....\finddialog.o
....................\................................................\.....\main.o
....................\................................................\.....\moc_finddialog.cpp
....................\................................................\.....\moc_finddialog.o
....................\................................................\release