In the Request flow, drag a MessageElementSetter primitive onto the canvas and wire the input primitive to its input terminal and its output terminal to the callout node.

在Request flow中，把一个MessageElementSetter primitive拖到画布中，把Input primitive连接到它的输入端，把它的输出端连接到callout节点。

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An input event might be raised by any input primitive, such as a mouse device, a stylus, or a finger.

输入事件可以由任何输入基元(如鼠标设备、触笔或手指)引发。

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However, as the millions of active mobile text message users in Asian and European countries have shown us, consumers are willing to input text even with primitive keypads.

ENGADGET: Switched On: Time to write off pen computing