blocks|key|1022744|text|首先，在您的onCreate中获取对ListPreference的引用。您可以使用findPreference()。例如：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1022745|ListPreference+pref+=+(ListPreference)+findPreference("thePreferencesKey");|code-block|syntax|javascript|1022746|然后，当您第一次加载活动时，只要首选项值发生更改，就可以使用想要获取ListPreference值的任何方法，并通过以下方式设置摘要：|1022747|pref.setSummary(theNewString);|1022748|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

First get a reference to the ListPreference in your onCreate. You can use findPreference(). For example:

<pre><code>ListPreference pref = (ListPreference) findPreference("thePreferencesKey");
</code></pre>

Then, when you first load the Activity and whenever the preferences value is changed, use whatever method you want to get the value of the ListPreference and set the summary with:

<pre><code>pref.setSummary(theNewString);
</code></pre>

blocks|key|1022775|text|您可以使用OnPreferenceChangeListener动态更改摘要。问题是它获取的是选定的值(来自android:entryValues)，而不是标题(android:entries)。在下面的代码中，我使用了toString()，但正确的解决方案是查找该值的标题。无论如何，这个想法是可行的：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1022776|public+class+Preferences+extends+PreferenceActivity+{
++++@Override
++++protected+void+onCreate(Bundle+savedInstanceState)+{
++++++++super.onCreate(savedInstanceState);
++++++++addPreferencesFromResource(R.xml.your_prefs);

++++++++ListPreference+listPreference+=+(ListPreference)+findPreference("preference_key");
++++++++if(listPreference.getValue()==null)+{
++++++++++++//+to+ensure+we+don't+get+a+null+value
++++++++++++//+set+first+value+by+default
++++++++++++listPreference.setValueIndex(0);
++++++++}
++++++++listPreference.setSummary(listPreference.getValue().toString());
++++++++listPreference.setOnPreferenceChangeListener(new+OnPreferenceChangeListener()+{
++++++++++++@Override
++++++++++++public+boolean+onPreferenceChange(Preference+preference,+Object+newValue)+{
++++++++++++++++preference.setSummary(newValue.toString());
++++++++++++++++return+true;
++++++++++++}
++++++++});
++++}
}|code-block|syntax|javascript|1022777|entityMap^0|5|Q|1H|J|28|F|31|A|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]|$9|R|A|S|B|C]|$9|T|A|U|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|V|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|W|8|@]|D|@]|E|$]]]|L|$]]

You can use <code>OnPreferenceChangeListener</code> to dynamically change the summary. The problem is that it gets the selected value (from <code>android:entryValues</code>), not the caption (<code>android:entries</code>). In the following code I used <code>toString()</code>, but the proper solution is to find the caption for the value. Anyways, the idea works:

<pre><code>public class Preferences extends PreferenceActivity {
 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 addPreferencesFromResource(R.xml.your_prefs);

 ListPreference listPreference = (ListPreference) findPreference("preference_key");
 if(listPreference.getValue()==null) {
 // to ensure we don't get a null value
 // set first value by default
 listPreference.setValueIndex(0);
 }
 listPreference.setSummary(listPreference.getValue().toString());
 listPreference.setOnPreferenceChangeListener(new OnPreferenceChangeListener() {
 @Override
 public boolean onPreferenceChange(Preference preference, Object newValue) {
 preference.setSummary(newValue.toString());
 return true;
 }
 });
 }
}
</code></pre>

blocks|key|808118|text|我也想实现类似的东西，但https://stackoverflow.com/a/8155029/592025的问题是，它显示了我的偏好的值(如1，2，3等)。我想显示与所选值对应的条目(人类可读的字符串)。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|808119|所以我以这种方式改变了它，并以我需要的方式工作。|808120|listPreference.setSummary(servicePreference.getEntry().toString());
listPreference.setOnPreferenceChangeListener(new+OnPreferenceChangeListener()+{

++++++++@Override
++++++++public+boolean+onPreferenceChange(Preference+preference,+Object+newValue)+{
++++++++++++//+Set+the+value+as+the+new+value
++++++++++++listPreference.setValue(newValue.toString());
++++++++++++//+Get+the+entry+which+corresponds+to+the+current+value+and+set+as+summary
++++++++++++preference.setSummary(listPreference.getEntry());
++++++++++++return+false;
++++++++}
++++});|code-block|syntax|javascript|808121|诀窍是使用getEntry()而不是getValue()，一旦更改了值，就显式设置该值并读回条目。|style|CODE|808122|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/8155029/592025^0|C|16|0|0|0|0|5|A|I|A|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@$A|X|B|Y|1|Z]]|C|$]]|$1|D|3|E|5|6|7|10|8|@]|9|@]|C|$]]|$1|F|3|G|5|H|7|11|8|@]|9|@]|C|$I|J]]|$1|K|3|L|5|6|7|12|8|@$A|13|B|14|M|N]|$A|15|B|16|M|N]]|9|@]|C|$]]|$1|O|3|-4|5|6|7|17|8|@]|9|@]|C|$]]]|P|$Q|$5|R|S|T|C|$U|V]]]]

I also wanted to achieve something similar, but the problem with <a href="https://stackoverflow.com/a/8155029/592025">https://stackoverflow.com/a/8155029/592025</a> is that, it shows the value for my preference (like 1, 2 3 etc). I want to show the entry (human readable string) corresponding to the selected value.

So I changed it this way and works the way I need it.

<pre><code>listPreference.setSummary(servicePreference.getEntry().toString());
listPreference.setOnPreferenceChangeListener(new OnPreferenceChangeListener() {

 @Override
 public boolean onPreferenceChange(Preference preference, Object newValue) {
 // Set the value as the new value
 listPreference.setValue(newValue.toString());
 // Get the entry which corresponds to the current value and set as summary
 preference.setSummary(listPreference.getEntry());
 return false;
 }
 });
</code></pre>

The trick is to use <code>getEntry()</code> instead of <code>getValue()</code> and once the value is changed, to set the value explicitly and read back the entry.

blocks|key|1022881|text|这是我正在使用的代码，它不会手动调用setValue，因为我相信这在以后的阶段已经完成了。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1022882|下面是一个示例：|1022883|@Override
public+boolean+onPreferenceChange(Preference+preference,+Object+value)
{
++++String+textValue+=+value.toString();

++++ListPreference+listPreference+=+(ListPreference)+preference;
++++int+index+=+listPreference.findIndexOfValue(textValue);

++++CharSequence[]+entries+=+listPreference.getEntries();

++++preference.setSummary(
++++++++++++++++index+>=+0
++++++++++++++++++++++++?+entries[index]
++++++++++++++++++++++++:+null);

++++return+true;
}|code-block|syntax|javascript|1022884|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

This is the code I'm using, it does not call setValue manually, as I believe this is already done at a later stage.

Here is an example:

<pre><code>@Override
public boolean onPreferenceChange(Preference preference, Object value)
{
 String textValue = value.toString();

 ListPreference listPreference = (ListPreference) preference;
 int index = listPreference.findIndexOfValue(textValue);

 CharSequence[] entries = listPreference.getEntries();

 preference.setSummary(
 index &gt;= 0
 ? entries[index]
 : null);

 return true;
}
</code></pre>

blocks|key|808222|text|这里是midhunhk答案的一个扩展版本，它也解决了有用的"android:summary“字符串|type|unstyled|depth|inlineStyleRanges|entityRanges|data|808223|++++++++//+Retrieve+&+populate+flash+modes
++++++++List<String>+flashmodes+=+params.getSupportedFlashModes();
++++++++if+(flashmodes+!=+null)+{
++++++++++++final+ListPreference+lp+=+(ListPreference)+findPreference("flash_list");
++++++++++++final+String+lp_basesummary+=+"Set+the+Flash+mode.+The+default+is+'auto'";

++++++++++++lp.setEntries(flashmodes.toArray(new+CharSequence[flashmodes.size()]));
++++++++++++lp.setEntryValues(flashmodes.toArray(new+CharSequence[flashmodes.size()]));
++++++++++++//+If+there's+only+one+option,+make+it+the+default
++++++++++++if+(flashmodes.size()+==+1)
++++++++++++++++lp.setValueIndex(0);

++++++++++++lp.setSummary(lp_basesummary+%2B+"+["+%2B+lp.getEntry()+%2B+"]");

++++++++++++lp.setOnPreferenceChangeListener(new+OnPreferenceChangeListener()+{

++++++++++++++++@Override
++++++++++++++++public+boolean+onPreferenceChange(Preference+preference,+Object+newValue)+{
++++++++++++++++++++//+Set+the+value+as+the+new+value
++++++++++++++++++++lp.setValue(newValue.toString());
++++++++++++++++++++//+Get+the+entry+which+corresponds+to+the+current+value
++++++++++++++++++++//+and+set+as+summary
++++++++++++++++++++preference.setSummary(lp_basesummary+%2B+"+["+%2B+lp.getEntry()+%2B+"]");
++++++++++++++++++++return+false;
++++++++++++++++}
++++++++++++});
++++++++}+else+{
++++++++++++//+Remove+the+preference
++++++++++++((PreferenceGroup)+findPreference("camera_preference")).removePreference(findPreference("flash_list"));
++++++++}

++++++++//+Retrieve+&+populate+focus+modes
++++++++List<String>+focusmodes+=+params.getSupportedFocusModes();
++++++++if+(focusmodes+!=+null)+{
++++++++++++final+ListPreference+lp+=+(ListPreference)+findPreference("focus_mode_list");
++++++++++++final+String+lp_basesummary+=+"Set+the+Focus+mode.+The+default+is+'auto'";
...|code-block|syntax|javascript|808224|为了清楚起见，android:summary从相关的xml中删除了。|808225|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Here's an expanded version of midhunhk's answer that addresses the helpful "android:summary" string as well

<pre><code> // Retrieve &amp; populate flash modes
 List&lt;String&gt; flashmodes = params.getSupportedFlashModes();
 if (flashmodes != null) {
 final ListPreference lp = (ListPreference) findPreference("flash_list");
 final String lp_basesummary = "Set the Flash mode. The default is 'auto'";

 lp.setEntries(flashmodes.toArray(new CharSequence[flashmodes.size()]));
 lp.setEntryValues(flashmodes.toArray(new CharSequence[flashmodes.size()]));
 // If there's only one option, make it the default
 if (flashmodes.size() == 1)
 lp.setValueIndex(0);

 lp.setSummary(lp_basesummary + " [" + lp.getEntry() + "]");

 lp.setOnPreferenceChangeListener(new OnPreferenceChangeListener() {

 @Override
 public boolean onPreferenceChange(Preference preference, Object newValue) {
 // Set the value as the new value
 lp.setValue(newValue.toString());
 // Get the entry which corresponds to the current value
 // and set as summary
 preference.setSummary(lp_basesummary + " [" + lp.getEntry() + "]");
 return false;
 }
 });
 } else {
 // Remove the preference
 ((PreferenceGroup) findPreference("camera_preference")).removePreference(findPreference("flash_list"));
 }

 // Retrieve &amp; populate focus modes
 List&lt;String&gt; focusmodes = params.getSupportedFocusModes();
 if (focusmodes != null) {
 final ListPreference lp = (ListPreference) findPreference("focus_mode_list");
 final String lp_basesummary = "Set the Focus mode. The default is 'auto'";
...
</code></pre>

And, just to be clear, android:summary is removed from the related xml.

blocks|key|1023008|text|这里有一种方法来处理用户选择后铃声首选项的摘要更新。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1023009|++++final+SharedPreferences+preference+=+PreferenceManager.getDefaultSharedPreferences(getApplicationContext());

++++final+RingtonePreference+rp_shuttle+=+(RingtonePreference)+findPreference("shuttle_tone");
++++rp_shuttle.setSummary(RingtoneManager
++++++++++++.getRingtone(getApplicationContext(),+Uri.parse(preference.getString("shuttle_tone",+"DEFAULT_SOUND")))
++++++++++++.getTitle(this));

++++rp_shuttle.setOnPreferenceChangeListener(new+OnPreferenceChangeListener()+{

++++++++public+boolean+onPreferenceChange(Preference+mypreference,+Object+newValue)+{
++++++++++++rp_shuttle.setSummary(RingtoneManager.getRingtone(getApplicationContext(),+Uri.parse(newValue+%2B+""))
++++++++++++++++++++.getTitle(getApplicationContext()));

++++++++++++return+true;
++++++++}
++++})|code-block|syntax|javascript|1023010|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

And here's one way to deal with the Ringtone preference's summary update following a user selection.

<pre><code> final SharedPreferences preference = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());

 final RingtonePreference rp_shuttle = (RingtonePreference) findPreference("shuttle_tone");
 rp_shuttle.setSummary(RingtoneManager
 .getRingtone(getApplicationContext(), Uri.parse(preference.getString("shuttle_tone", "DEFAULT_SOUND")))
 .getTitle(this));

 rp_shuttle.setOnPreferenceChangeListener(new OnPreferenceChangeListener() {

 public boolean onPreferenceChange(Preference mypreference, Object newValue) {
 rp_shuttle.setSummary(RingtoneManager.getRingtone(getApplicationContext(), Uri.parse(newValue + ""))
 .getTitle(getApplicationContext()));

 return true;
 }
 })
</code></pre>

blocks|key|1023090|text|您的PreferenceActivity上有一个方法bindPreferenceSummaryToValue，|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1023091|您可以轻松地将摘要添加到列表中，如下所示：|1023092|private+static+void+bindPreferenceSummaryToValue(Preference+preference)+{
++++preference.setOnPreferenceChangeListener(sBindPreferenceSummaryToValueListener);

++++sBindPreferenceSummaryToValueListener.onPreferenceChange(preference,
++++++++++++PreferenceManager
++++++++++++++++++++.getDefaultSharedPreferences(preference.getContext())
++++++++++++++++++++.getString(preference.getKey(),+""));
}|code-block|syntax|javascript|1023093|在你的OnCreate方法中，你可以像这样调用绑定函数：|1023094|bindPreferenceSummaryToValue(findPreference(getString(R.string.KEY_OF_THE_LIST)));|1023095|您可以通过相同的方式轻松添加其他摘要：|1023096|bindPreferenceSummaryToValue(findPreference(getString(R.string.KEY_1)));
bindPreferenceSummaryToValue(findPreference(getString(R.string.KEY_2)));
bindPreferenceSummaryToValue(findPreference(getString(R.string.KEY_3)));|1023097|entityMap^0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|T|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|V|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|W|8|@]|9|@]|A|$G|H]]|$1|M|3|N|5|6|7|X|8|@]|9|@]|A|$]]|$1|O|3|P|5|F|7|Y|8|@]|9|@]|A|$G|H]]|$1|Q|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]]|R|$]]

You hava a method bindPreferenceSummaryToValue on your PreferenceActivity,

you can easily add the summary to the list doing like this:

<pre><code>private static void bindPreferenceSummaryToValue(Preference preference) {
 preference.setOnPreferenceChangeListener(sBindPreferenceSummaryToValueListener);

 sBindPreferenceSummaryToValueListener.onPreferenceChange(preference,
 PreferenceManager
 .getDefaultSharedPreferences(preference.getContext())
 .getString(preference.getKey(), ""));
}
</code></pre>

On yout OnCreate method you call the bind function like this:

<pre><code>bindPreferenceSummaryToValue(findPreference(getString(R.string.KEY_OF_THE_LIST)));
</code></pre>

You can easily add others summary on the same way:

<pre><code>bindPreferenceSummaryToValue(findPreference(getString(R.string.KEY_1)));
bindPreferenceSummaryToValue(findPreference(getString(R.string.KEY_2)));
bindPreferenceSummaryToValue(findPreference(getString(R.string.KEY_3)));
</code></pre>

blocks|key|1023124|text|在onCreatePreferences下执行以下操作：：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1023125|SharedPreferences+sharedPreferences+=getPreferenceScreen().getSharedPreferences();
PreferenceScreen+prefScreen+=+getPreferenceScreen();
int+count+=+prefScreen.getPreferenceCount();

for+(int+i+=+0;+i+<+count;+i%2B%2B)+{
++Preference+p+=+prefScreen.getPreference(i);
++++if+(p+instanceof+ListPreference)+{
+++++++String+value+=+sharedPreferences.getString(p.getKey(),+"");
+++++++ListPreference+listPreference+=+(ListPreference)+preference;
+++++++int+prefIndex+=+listPreference.findIndexOfValue(stringValue);
+++++++if+(prefIndex+>=+0)+{
++++++++++++preference.setSummary(listPreference.getEntries()[prefIndex]);
++++++}
++++}
+}++|code-block|syntax|javascript|1023126|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

under onCreatePreferences do this::

<pre><code>SharedPreferences sharedPreferences =getPreferenceScreen().getSharedPreferences();
PreferenceScreen prefScreen = getPreferenceScreen();
int count = prefScreen.getPreferenceCount();

for (int i = 0; i &lt; count; i++) {
 Preference p = prefScreen.getPreference(i);
 if (p instanceof ListPreference) {
 String value = sharedPreferences.getString(p.getKey(), "");
 ListPreference listPreference = (ListPreference) preference;
 int prefIndex = listPreference.findIndexOfValue(stringValue);
 if (prefIndex &gt;= 0) {
 preference.setSummary(listPreference.getEntries()[prefIndex]);
 }
 }
 } 
</code></pre>

blocks|key|1023199|text|我认为您正在寻找的内容非常简单，您可以将以下代码行添加到您的Preference项目中：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1023200|android:summary="%251$s"|code-block|syntax|javascript|1023201|所以它看起来像这样：|1023202|<ListPreference
++++++++++++android:key="@string/pref_temp_key"
++++++++++++android:title="@string/pref_temp_title"
++++++++++++android:dialogTitle="@string/pref_temp_dialog_title"
++++++++++++android:entries="@array/pref_tempUnit_entries"
++++++++++++android:entryValues="@array/pref_tempUnit_entries"
++++++++++++android:summary="%251$s"
++++++++++++android:defaultValue="@string/pref_temp_default_value"+/>|1023203|entityMap^0|U|A|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|U|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|V|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|W|8|@]|D|@]|E|$]]]|P|$]]

I think that what you are looking for is much simple that you can think, add the following code line to your <code>Preference</code> item: 

<pre><code>android:summary="%1$s"
</code></pre>

So it will look something like this: 

<pre><code>&lt;ListPreference
 android:key="@string/pref_temp_key"
 android:title="@string/pref_temp_title"
 android:dialogTitle="@string/pref_temp_dialog_title"
 android:entries="@array/pref_tempUnit_entries"
 android:entryValues="@array/pref_tempUnit_entries"
 android:summary="%1$s"
 android:defaultValue="@string/pref_temp_default_value" /&gt;
</code></pre>

blocks|key|1023248|text|非常简单-只需将以下属性添加到XML定义中-|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1023249|<ListPreference
...++++
app:useSimpleSummaryProvider="true"
...
/>|code-block|syntax|javascript|1023250|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

So simple - just add the following property to your XML definition -
<pre class="lang-xml prettyprint-override"><code>&lt;ListPreference
... 
app:useSimpleSummaryProvider=&quot;true&quot;
...
/&gt;
</code></pre>

I have a Preference activity which uses a List Preferences as defined by my XML file. How would I set the summary of the list activity to the value that is selected?

Android List Preferences: have summary as selected value?

我有一个首选项活动，它使用XML文件定义的列表首选项。如何将列表活动的摘要设置为所选的值？

问Android列表首选项:是否将摘要作为选定值？
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问Android列表首选项:是否将摘要作为选定值？
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