By clicking the Alert button in the example application, you can see this bubble message in action. Here's the code that implements it.

单击示例应用程序的Alert按钮，就可以看到实际运用中的泡泡消息。

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The action will display a simple alert message when the user clicks the button.

当用户单击按钮时，该活动将显示一个简单的警报消息。

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Consider the confusion for a user if the Back button suddenly triggered mysterious alert prompts or sent him to a new Web site.

设想一下，如果后退按钮突然弹出一个神秘的警告提示或者用户被打发到一个新的网站上去，用户该是多么困惑。

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There's also an emergency alert button your relative can wear around his or her neck.

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Not known as an alarmist, he is now pressing the red alert button.

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It returned to the store a few days later after adding an in-app button to let users alert the service to inappropriate pictures.

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