Add Loop Event

It makes a difference if you loop through 500 or 5000 DOM elements on the page when you want to add an event handler for example.

如果您依次通过页上的500或5000 DOM元素，当您要添加事件处理程序，例如，它使不同。

The skeleton of an application consists of just four steps: (1) create an application; (2) create one or more Windows; (3) add some widgets to the Windows; (4) call the app.run event-loop.

应用程序的主框架只由四个步骤组成：(1)创建一个应用程序；(2)创建一个或多个窗口；(3)在窗口中添加一些窗口小部件；(4)调用app . run事件循环。