如何将 Spinner 默认值设置为 null? [英] How to set Spinner default value to null?

问题描述

我试图在没有选定值的情况下加载 Spinner.一旦用户选择了一个值，它就会将他们带到另一个页面.

I'm trying to get a Spinner to load up with no selected value. Once the user selects a value it then takes them to another page.

这被证明是一个问题，因为目前，页面会在用户做出选择之前立即加载.

This is proving to be a problem because at present, the page just loads straight away before the user gets a choice to choose.

我的微调器类的设置方式与 Google 的相同:http://developer.android.com/resources/tutorials/views/hello-spinner.html

My spinner class is set up the same way as Google's: http://developer.android.com/resources/tutorials/views/hello-spinner.html

所以基本上，是否有可能有一个微调器在没有选择的情况下加载，因为目前它加载了我的字符串数组中的第一项.

So basically, is it possible have a spinner that loads with nothing selected because at present, it loads the first item in my string array.

推荐答案

是否有可能在没有选择任何内容的情况下加载一个微调器

is it possible have a spinner that loads with nothing selected

仅当没有数据时.如果 SpinnerAdapter 中有 1 个以上的项目，Spinner 将始终有一个选择.

Only if there is no data. If you have 1+ items in the SpinnerAdapter, the Spinner will always have a selection.

Spinners 并非设计为命令小部件.用户不会期望 Spinner 中的选择来启动活动.请考虑使用其他东西，例如 ListView 或 GridView，而不是 Spinner.

Spinners are not designed to be command widgets. Users will not expect a selection in a Spinner to start an activity. Please consider using something else, like a ListView or GridView, instead of a Spinner.

编辑

顺便说一句，我忘了提——你总是可以在你的适配器中添加一个代表无选择"的额外条目，并使其成为Spinner中的初始选定项.

BTW, I forgot to mention -- you can always put an extra entry in your adapter that represents "no selection", and make it the initial selected item in the Spinner.

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