在Android Studio中，打开“root_preferences.xml”，选择设计模式。选择所需的EditTextPreference首选项，在“所有属性”下，寻找“useSimpleSummaryProvider”属性，并将其设置为true。然后它将显示当前值。

Here,all these are cut from Eclipse sample SettingsActivity. I have to copy all these too much codes to show how these android developers choose perfectly for more generalized and stable coding style. I left the codes for adapting the PreferenceActivity to tablet and greater API. public class SettingsActivity extends PreferenceActivity { @Override protected void onPostCreate(Bundle savedInstanceState) { super.onPostCreate(savedInstanceState); setupSummaryUpdatablePreferencesScreen(); } private void setupSummaryUpdatablePreferencesScreen() { // In the simplified UI, fragments are not used at all and we instead // use the older PreferenceActivity APIs. // Add 'general' preferences. addPreferencesFromResource(R.xml.pref_general); // Bind the summaries of EditText/List/Dialog preferences to // their values. When their values change, their summaries are updated // to reflect the new value, per the Android Design guidelines. bindPreferenceSummaryToValue(findPreference("example_text")); bindPreferenceSummaryToValue(findPreference("example_list")); } /** * A preference value change listener that updates the preference's summary * to reflect its new value. */ private static Preference.OnPreferenceChangeListener sBindPreferenceSummaryToValueListener = new Preference.OnPreferenceChangeListener() { private String TAG = SettingsActivity.class.getSimpleName(); @Override public boolean onPreferenceChange(Preference preference, Object value) { String stringValue = value.toString(); if (preference instanceof ListPreference) { // For list preferences, look up the correct display value in // the preference's 'entries' list. ListPreference listPreference = (ListPreference) preference; int index = listPreference.findIndexOfValue(stringValue); // Set the summary to reflect the new value. preference.setSummary( index >= 0 ? listPreference.getEntries()[index] : null); } else { // For all other preferences, set the summary to the value's // simple string representation. preference.setSummary(stringValue); } Log.i(TAG, "pref changed : " + preference.getKey() + " " + value); return true; } }; /** * Binds a preference's summary to its value. More specifically, when the * preference's value is changed, its summary (line of text below the * preference title) is updated to reflect the value. The summary is also * immediately updated upon calling this method. The exact display format is * dependent on the type of preference. * * @see #sBindPreferenceSummaryToValueListener */ private static void bindPreferenceSummaryToValue(Preference preference) { // Set the listener to watch for value changes. preference.setOnPreferenceChangeListener(sBindPreferenceSummaryToValueListener); // Trigger the listener immediately with the preference's // current value. sBindPreferenceSummaryToValueListener.onPreferenceChange(preference, PreferenceManager .getDefaultSharedPreferences(preference.getContext()) .getString(preference.getKey(), "")); } } xml/pref_general.xml <PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android" > <!-- NOTE: EditTextPreference accepts EditText attributes. --> <!-- NOTE: EditTextPreference's summary should be set to its value by the activity code. --> <EditTextPreference android:capitalize="words" android:defaultValue="@string/pref_default_display_name" android:inputType="textCapWords" android:key="example_text" android:maxLines="1" android:selectAllOnFocus="true" android:singleLine="true" android:title="@string/pref_title_display_name" /> <!-- NOTE: Hide buttons to simplify the UI. Users can touch outside the dialog todismiss it.--> <!-- NOTE: ListPreference's summary should be set to its value by the activity code. --> <ListPreference android:defaultValue="-1" android:entries="@array/pref_example_list_titles" android:entryValues="@array/pref_example_list_values" android:key="example_list" android:negativeButtonText="@null" android:positiveButtonText="@null" android:title="@string/pref_title_add_friends_to_messages" /> </PreferenceScreen> values/strings_activity_settings.xml <resources> <!-- Strings related to Settings --> <!-- Example General settings --> <string name="pref_title_display_name">Display name</string> <string name="pref_default_display_name">John Smith</string> <string name="pref_title_add_friends_to_messages">Add friends to messages</string> <string-array name="pref_example_list_titles"> <item>Always</item> <item>When possible</item> <item>Never</item> </string-array> <string-array name="pref_example_list_values"> <item>1</item> <item>0</item> <item>-1</item> </string-array> </resources> NOTE: Actually I just want to comment like "Google's sample for PreferenceActivity is also interesting". But I haven't enough reputation points.So please don't blame me. (Sorry for bad English)

简洁的解决方案只需一行代码:

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    addPreferencesFromResource(R.xml.preferences);

    bindPreferenceSummaryToValue(findPreference("mySetting"));

    // initialize summary
    sBindPreferenceSummaryToValueListener.onPreferenceChange(findPreference("mySetting"), 
        ((ListPreference) findPreference("mySetting")).getEntry());
}

谢谢你的建议!

我有一个首选项屏幕，并希望显示每个列表首选项的值作为摘要。

这就是我现在的方式:

public class Preferences extends PreferenceActivity implements OnSharedPreferenceChangeListener {

@Override
protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        addPreferencesFromResource(R.xml.preferences);
}

@Override
protected void onResume() {
    super.onResume();

    // Set up initial values for all list preferences
    Map<String, ?> sharedPreferencesMap = getPreferenceScreen().getSharedPreferences().getAll();
    Preference pref;
    ListPreference listPref;
    for (Map.Entry<String, ?> entry : sharedPreferencesMap.entrySet()) {
        pref = findPreference(entry.getKey());
        if (pref instanceof ListPreference) {
            listPref = (ListPreference) pref;
            pref.setSummary(listPref.getEntry());
        }
    }

    // Set up a listener whenever a key changes            
    getPreferenceScreen().getSharedPreferences().registerOnSharedPreferenceChangeListener(this);
}

@Override
protected void onPause() {
    super.onPause();

    // Unregister the listener whenever a key changes            
    getPreferenceScreen().getSharedPreferences().unregisterOnSharedPreferenceChangeListener(this);    
}

public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
    Preference pref = findPreference(key);

    if (pref instanceof ListPreference) {
        ListPreference listPref = (ListPreference) pref;
        pref.setSummary(listPref.getEntry());
    }
}

这对我来说是可行的，但我想知道最好的解决方案(性能、稳定性、可伸缩性)是Koem展示的那个还是这个?

也许像ListPreference:修改getSummary来得到你想要的:

package your.package.preference;

import android.content.Context;
import android.util.AttributeSet;

public class EditTextPreference extends android.preference.EditTextPreference{
        public EditTextPreference(Context context, AttributeSet attrs, int defStyle) {
            super(context, attrs, defStyle);
        }

        public EditTextPreference(Context context, AttributeSet attrs) {
            super(context, attrs);
        }

        public EditTextPreference(Context context) {
            super(context);
        }

        @Override
        public CharSequence getSummary() {
            if(super.getSummary() == null) return null;

            String summary = super.getSummary().toString();
            return String.format(summary, getText());
        }
    }

在你的xml中使用这个:

<your.package.EditTextPreference
                android:key="pref_alpha"
                android:summary="Actual value: %s"
                android:title="Title"
                android:defaultValue="default"
                />

因此，您可以使用%s而不是实际值编写摘要。

实际上，CheckBoxPreference确实能够根据复选框值指定不同的摘要。请参阅android:summaryOff和android:summaryOn属性(以及相应的CheckBoxPreference方法)。