Android的微调：获取所选择的项目更改事件 [英] Android Spinner: Get the selected item change event

问题描述

您如何设置的事件侦听器的微调时，所选项目的变化？

基本上，我试图做的是类似这样的：

  spinner1.onSelectionChange = handleSelectionChange;

无效handleSelectionChange（对象发件人）{
    //处理事件
}
 

解决方案

有些previous答案是不正确的。他们的工作对其他部件和看法，但对于文件<一个href="http://developer.android.com/reference/android/widget/Spinner.html#setOnItemClickListener%28android.widget.AdapterView.OnItemClickListener%29">Spinner小部件明确规定：

  

一个微调不支持的项目点击   事件。调用此方法将引发   一个例外。

更好地利用<一href="http://developer.android.com/reference/android/widget/AdapterView.OnItemSelectedListener.html">OnItemSelectedListener()而不是：

  spinner.setOnItemSelectedListener（新OnItemSelectedListener（）{
    @覆盖
    公共无效onItemSelected（适配器视图＆LT;＆GT; parentView，查看selectedItemView，INT位置，长的id）{
        //你的code在这里
    }

    @覆盖
    公共无效onNothingSelected（适配器视图＆LT;＆GT; parentView）{
        //你的code在这里
    }

}）;
 

这对我的作品。

请注意，还调用onItemSelected方法时的观点正在构建，这样你就可以考虑把它放在的onCreate（）方法调用。

How can you set the event listener for a Spinner when the selected item changes?

Basically what I am trying to do is something similar to this:

spinner1.onSelectionChange = handleSelectionChange;

void handleSelectionChange(Object sender){
    //handle event
}

解决方案

Some of the previous answers are not correct. They work for other widgets and views, but the documentation for the Spinner widget clearly states:

A spinner does not support item click events. Calling this method will raise an exception.

Better use OnItemSelectedListener() instead:

spinner.setOnItemSelectedListener(new OnItemSelectedListener() {
    @Override
    public void onItemSelected(AdapterView<?> parentView, View selectedItemView, int position, long id) {
        // your code here
    }

    @Override
    public void onNothingSelected(AdapterView<?> parentView) {
        // your code here
    }

});

This works for me.

Note that onItemSelected method is also invoked when the view is being build, so you can consider putting it inside onCreate() method call.

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