我发现这种方法使EditTextPreference从支持库句柄“%s”在总结(因为ListPreference已经处理):

public class EditTextPreference extends android.support.v7.preference.EditTextPreference {
    public EditTextPreference(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    public void setText(String text) {
        super.setText(text);
        notifyChanged();
    }

    @Override
    public CharSequence getSummary() {
        String text = super.getText();
        String summary = super.getSummary().toString();
        return String.format(summary, text == null ? "" : text);
    }
}

在xml中它看起来是这样的:

<com.example.yourapp.EditTextPreference
    android:defaultValue="1"
    android:key="cleanup_period"
    android:summary="Clean up messages after %s days"
    android:title="Clean up period" />

简单:

listPreference.setSummary("%s");

在我花了几个小时来解决这样的问题后，我实现了以下代码:

[更新:最终版本列表]

public class MyPreferencesActivity extends PreferenceActivity {
    ...
    ListPreference m_updateList;
    ...
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        addPreferencesFromResource(R.xml.preferences);

        m_updateList = (ListPreference) findPreference(getString(R.string.pref_update_interval_key));
        String currentValue = m_updateList.getValue();
        if (currentValue == null) {
            m_updateList.setValue((String)m_updateList.getEntryValues()[DEFAULT_UPDATE_TIME_INDEX]);
            currentValue = m_updateList.getValue();
        }
        updateListSummary(currentValue);    

        m_updateList.setOnPreferenceChangeListener(new OnPreferenceChangeListener() {
            @Override
            public boolean onPreferenceChange(Preference preference, Object newValue) {
                updateListSummary(newValue.toString());
                return true;
            }       
        });     
    }

    private void updateListSummary(String newValue) {
        int index = m_updateList.findIndexOfValue(newValue);
        CharSequence entry = m_updateList.getEntries()[index];
        m_updateList.setSummary(entry);
    }
}

这是唯一对我有效的解决方法。在我尝试子类从ListPreferences和实现android:summary="bla bla bla %s"。既不工作。

以下是我的解决方案:

构建一个首选项类型“getter”方法。

protected String getPreference(Preference x) {
    // http://stackoverflow.com/questions/3993982/how-to-check-type-of-variable-in-java
    if (x instanceof CheckBoxPreference)
        return "CheckBoxPreference";
    else if (x instanceof EditTextPreference)
        return "EditTextPreference";
    else if (x instanceof ListPreference)
        return "ListPreference";
    else if (x instanceof MultiSelectListPreference)
        return "MultiSelectListPreference";
    else if (x instanceof RingtonePreference)
        return "RingtonePreference";
    else if (x instanceof SwitchPreference)
        return "SwitchPreference";
    else if (x instanceof TwoStatePreference)
        return "TwoStatePreference";
    else if (x instanceof DialogPreference) // Needs to be after ListPreference
        return "DialogPreference";
    else
        return "undefined";
}

构建一个'setSummaryInit'方法。

public void onSharedPreferenceChanged(SharedPreferences prefs, String key) {
        Log.i(TAG, "+ onSharedPreferenceChanged(prefs:" + prefs + ", key:" + key + ")");
        if( key != null ) {
            updatePreference(prefs, key);
            setSummary(key);
        } else {
            Log.e(TAG, "Preference without key!");
        }
        Log.i(TAG, "- onSharedPreferenceChanged()");
    }

    protected boolean setSummary() {
        return _setSummary(null);
    }
    
    protected boolean setSummary(String sKey) {
        return _setSummary(sKey);
    }
    
    private boolean _setSummary(String sKey) {
        if (sKey == null) Log.i(TAG, "Initializing");
        else Log.i(TAG, sKey);
        
        // Get Preferences
        SharedPreferences sharedPrefs = PreferenceManager
                .getDefaultSharedPreferences(this);

        // Iterate through all Shared Preferences
        // http://stackoverflow.com/questions/9310479/how-to-iterate-through-all-keys-of-shared-preferences
        Map<String, ?> keys = sharedPrefs.getAll();
        for (Map.Entry<String, ?> entry : keys.entrySet()) {
            String key = entry.getKey();
            // Do work only if initializing (null) or updating specific preference key
            if ( (sKey == null) || (sKey.equals(key)) ) {
                String value = entry.getValue().toString();
                Preference pref = findPreference(key);
                String preference = getPreference(pref);
                Log.d("map values", key + " | " + value + " | " + preference);
                pref.setSummary(key + " | " + value + " | " + preference);
                if (sKey != null) return true;
            }
        }
        return false;
    }

    private void updatePreference(SharedPreferences prefs, String key) {
        Log.i(TAG, "+ updatePreference(prefs:" + prefs + ", key:" + key + ")");
        Preference pref = findPreference(key);
        String preferenceType = getPreference(pref);
        Log.i(TAG, "preferenceType = " + preferenceType);
        Log.i(TAG, "- updatePreference()");
    }

初始化

创建一个公共类PreferenceActivity并实现OnSharedPreferenceChangeListener

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    PreferenceManager.setDefaultValues(this, R.xml.global_preferences,
    false);
    this.addPreferencesFromResource(R.xml.global_preferences);
    this.getPreferenceScreen().getSharedPreferences()
        .registerOnSharedPreferenceChangeListener(this);
}

protected void onResume() {
    super.onResume();
    setSummary();
}

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。

FYI:

findPreference(CharSequence key)
This method was deprecated in API level 11. This function is not relevant
for a modern fragment-based PreferenceActivity.

更有理由看看上面@ASD的非常圆滑的答案(来源在这里找到)，它说在android:summary中对preferences.xml中的每个字段使用%s。(首选项的当前值替换为%s。)

<ListPreference
 ...        
 android:summary="Length of longest word to return as match is %s"
 ...
 />