How to open ListPreference immediately when activity is created?

Question

I have an application with two screens, MainActivity - screen with buttons, and SecondActivity - settings screen. In this SecondActivity I have one ListPreference.

How to open this ListPreference when SecondActivity is opening?

Answer 1

首先，您需要计算ListPreference中PreferenceScreen的位置。然后尝试以下代码：

PreferenceScreen main = (PreferenceScreen)findPreference(getString(R.string.pref_screen_root));
    main.onItemClick(null, null, pos, 0);

此处 pos 是ListPreference中PreferenceScreen的 位置 。 R.string.pref_screen_root是PreferenceScreen的关键。

以下是最简单的xml文件：

  <?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android"
    android:key="@string/pref_screen_root" >
 <ListPreference
            android:defaultValue="0"
            android:entries="@array/list_entries"
            android:entryValues="@array/list_values"
            android:icon="@drawable/ic_earth"
            android:key="@string/pref_country"
            android:title="Select a country" />
</PreferenceScreen>