一个Widget平生也许都有五个时代:
1. 创立(Creation):宣布一个物件(declaring an object)
2. 放置(Placement):将它到场一个容器中(adding it to a container)
3. 旌旗灯号毗连(Signal Connection):吸收旌旗灯号和停止举措(the action it will perform)
4. 显示(Display):它是不是是可见的(whether it is viewable or not)
5. 删除(Destruction):封闭程式(closing of a program)