Android ListView-获取所选项目 [英] Android ListView - get the selected item

问题描述

我已经使用自定义数组适配器实现了列表视图.现在，我要获取列表视图的选定项.我知道有一些使用onclick侦听器的解决方案.但是，我想使用ListView(AdapterView)类的getSelectedItem()方法.该方法始终返回null.其他getSelected *方法也不起作用.

I have implemented a list view using a custom array adapter. Now I want to get the selected item of the list view. I know that there are solutions using onclick listeners. However I would like to use the getSelectedItem() method of the ListView (AdapterView) class. The method always returns null. The other getSelected* methods also do not work.

// onCreate
    mList = (ListView) findViewById(R.id.listView);

// set in Broadcast Receiver (inner class)
    mList.setAdapter(new ListAdapter(getApplicationContext(),
                R.layout.list_view_item, R.id.textView,
                itemList));

// onButtonClick
    Log.i(TAG, "Selected: " + mList.getSelectedItem());

OnButtonClick是一个单独按钮的回调.如果单击它，则所选项目应在logcat中打印，但每次返回null.谁能帮我吗?

OnButtonClick is a callback of a seperate button. If I click on it the selected item should be printed in logcat but it returns everytime null. Can anyone help me?

XML:

<ListView
    android:id="@+id/listView"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_centerHorizontal="true"
    android:layout_centerVertical="true"
    android:background="@android:color/background_light"
    android:drawSelectorOnTop="false"
    android:listSelector="@android:color/holo_blue_light" >
</ListView>

<Button
    android:id="@+id/buttonContinue"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_below="@id/listView"
    android:layout_centerHorizontal="true"
    android:onClick="onButtonClickContinue"
    android:text="Continue" />
</RelativeLayout>

如果我选择一个项目，颜色就会改变.

If I select an item the color changes.

推荐答案

我发现从不/很少在触摸设备上调用OnItemSelected方法. 如果您使用仿真器交叉导航，并且在具有混合或非触摸控制的特殊设备上触发，则它将触发.仅当您滚动列表时才调用它，而单击时不会调用.

I figured out that the OnItemSelected method is never/rarely called on touch devices. It fires up if you use the emulator cross-navigation and on special devices with hybrid or non-touch control. It is only called if you scroll through the list but not if you click on it.

这就是为什么您应该在具有触摸控制功能的普通平板电脑/智能手机上使用OnItemClickListener.

Thats why you should use the OnItemClickListener on a general tablet/smartphone with touch control.

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