Fragments can be added, removed, replaced, and animated inside an Activity dynamically, and they are modular and reusable across multiple Activities.

在活动中可以动态的对片断进行添加，删除，更换或使之呈现动画效果。而且，片断是模块化、可复用的，可以跨越多个活动进行使用。

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Planning: Activities that take place at multiple levels, with different goals.

制定计划：发生在多个层级的活动，有不同的目标。

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Multiple onEvent and onAlarm events can occur concurrently and they are treated as concurrent activities.

多个 onEvent 和 onAlarm 事件可以并发出现，它们将作为并发活动对待。

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The Ultimate's 2.4-inch touchscreen serves as a number pad, a favorite channel list for easy hopping, and is the home of one-touch "activities, " which are basically macros for issuing multiple commands.

ENGADGET