Question

Android dev的新手，从iOS切换到黑暗面，请不要讨厌。

问题： 我将compile 'com.android.support:preference-v7:27.0.0'添加到了Gradle中。我在styles.xml中指定了一个主题。但是，我仍然收到如下所示的错误消息。如何解决这个问题？

java.lang.IllegalStateException: Must specify preferenceTheme in theme

at android.support.v7.preference.PreferenceFragmentCompat.onCreate(PreferenceFragmentCompat.java:211)

参考文献：Stackoverflow answer，Medium article

SettingsFragment

public class SettingsFragment extends PreferenceFragmentCompat {
    private SwitchPreferenceCompat receiveReminders;
    private ListPreference notifyMe;

    @Override
    public void onCreatePreferences(@Nullable Bundle savedInstanceState, String rootKey)
    {
        super.onCreate(savedInstanceState);
        addPreferencesFromResource(R.xml.preferences);

        receiveReminders = (SwitchPreferenceCompat) findPreference(R.string.key_receive_reminders);
        notifyMe = (ListPreference) findPreference(R.string.key_notify_me);
    }
}

styles.xml

<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
    <item name="preferenceTheme">@style/PreferenceThemeOverlay</item>
</style>

的preferences.xml

 <PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
<PreferenceCategory
    android:title="@string/settings_category_notifications">
    <SwitchPreferenceCompat
        android:key="@string/key_receive_reminders"
        android:title="@string/settings_receive_reminders"
        android:defaultValue="true"/>
    <ListPreference
        android:key="@string/key_notify_me"
        android:title="@string/settings_notify_me"
        android:summary="%s"
        android:entries="@array/settings_notify_me_titles"
        android:entryValues="@array/settings_notify_me_titles"
        android:defaultValue="@string/notify_me_2_hours"
        android:positiveButtonText="@null"
        android:dependency="@string/key_receive_reminders"/>
</PreferenceCategory>
</PreferenceScreen>

Answer 1

请确保在您的AndroidManifest.xml文件中设置应用和/或活动的主题，否则将无法找到偏好主题：

<activity
    android:name=".MainActivity"
    android:theme="@style/AppTheme">
</activity>

必须在PreferenceFragmentCompat的主题中指定preferenceTheme

1 个答案: