在我的应用中,我正在尝试设置首选项,允许您从ListPreference中的大量选项中更改布局的背景图像。 我的偏好xml:
<PreferenceCategory android:title="Favorite Team">
<ListPreference
android:title="Favorite Team"
android:summary="@string/prefs_pick_fav_team"
android:key="keyFavTeam"
android:entries="@array/teams"
android:entryValues="@array/teams_values"
android:defaultValue="0"
/>
</PreferenceCategory>
PreferencesActivity,也在Manifest中:
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
addPreferencesFromResource(R.xml.prefs);
}
然后这是我想要更改背景的屏幕onCreate的代码:
SharedPreferences SP = PreferenceManager
.getDefaultSharedPreferences(getBaseContext());
String strFavTeam = SP.getString("keyFavTeam", "0");
LinearLayout linearLayout = (LinearLayout) this.findViewById(R.id.main_screen);
if(strFavTeam.equals("0")){
linearLayout.setBackgroundResource(R.drawable.first_screen);
}
if(strFavTeam.equals("73")){
linearLayout.setBackgroundResource(R.drawable.tennessee_screen);
}
if(strFavTeam.equals("67")){
linearLayout.setBackgroundResource(R.drawable.georgia_screen);
}
我的问题是,当我从ListPreference中选择Tennessee(其值为73)时,我会收到一个强制关闭。
这是来自LogCat的堆栈跟踪:
07-14 23:43:35.535: ERROR/AndroidRuntime(5581): FATAL EXCEPTION: main
07-14 23:43:35.535: ERROR/AndroidRuntime(5581): java.lang.ArrayIndexOutOfBoundsException
07-14 23:43:35.535: ERROR/AndroidRuntime(5581): at android.preference.ListPreference.onDialogClosed(ListPreference.java:218)
07-14 23:43:35.535: ERROR/AndroidRuntime(5581): at android.preference.DialogPreference.onDismiss(DialogPreference.java:383)
07-14 23:43:35.535: ERROR/AndroidRuntime(5581): at android.app.Dialog$ListenersHandler.handleMessage(Dialog.java:1047)
07-14 23:43:35.535: ERROR/AndroidRuntime(5581): at android.os.Handler.dispatchMessage(Handler.java:99)
07-14 23:43:35.535: ERROR/AndroidRuntime(5581): at android.os.Looper.loop(Looper.java:130)
07-14 23:43:35.535: ERROR/AndroidRuntime(5581): at android.app.ActivityThread.main(ActivityThread.java:3683)
07-14 23:43:35.535: ERROR/AndroidRuntime(5581): at java.lang.reflect.Method.invokeNative(Native Method)
07-14 23:43:35.535: ERROR/AndroidRuntime(5581): at java.lang.reflect.Method.invoke(Method.java:507)
07-14 23:43:35.535: ERROR/AndroidRuntime(5581): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
07-14 23:43:35.535: ERROR/AndroidRuntime(5581): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
07-14 23:43:35.535: ERROR/AndroidRuntime(5581): at dalvik.system.NativeStart.main(Native Method)
有人可以告诉我我需要做些什么来防止这种情况并继续改变背景?
由于
答案 0 :(得分:1)
您的问题是您使用的索引大于数组的大小。来自Android源的失败的实际行是:
String value = mEntryValues[mClickedDialogEntryIndex].toString();
因此,@array/teams
和@array/teams_values
的长度可能不匹配,或者您的值不完整。