刚学qt时编写的一个“hello World”程序，运行时弹出一个“hello world”对话框，点击“QT简介”按钮，弹出一段对qt的简介，关闭后回到“hello World”界面。适合初学者学习。-It is a progrome for "hello World" which I writed when just learn at qt. When it is running, it pop up a "hello world" dialog.Clicked on "the QT Pro