使用Eclipse PreferenceActivity Generator，它生成了必要的文件，以便为我的应用添加设置。它适用于小型设备，但在平板电脑上崩溃。 logcat的：
05-09 10:56:45.812: E/AndroidRuntime(1823): FATAL EXCEPTION: main
05-09 10:56:45.812: E/AndroidRuntime(1823): Process: com.nextgenintl.aimassistant, PID: 1823
05-09 10:56:45.812: E/AndroidRuntime(1823): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.nextgenintl.aimassistant/com.nextgenintl.aimassistant.PrefsActivity}: java.lang.RuntimeException: Subclasses of PreferenceActivity must override isValidFragment(String) to verify that the Fragment class is valid! com.nextgenintl.aimassistant.PrefsActivity has not checked if fragment com.nextgenintl.aimassistant.SettingsActivity$GeneralPreferenceFragment is valid.
05-09 10:56:45.812: E/AndroidRuntime(1823): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
05-09 10:56:45.812: E/AndroidRuntime(1823): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
05-09 10:56:45.812: E/AndroidRuntime(1823): at android.app.ActivityThread.access$800(ActivityThread.java:135)
05-09 10:56:45.812: E/AndroidRuntime(1823): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
05-09 10:56:45.812: E/AndroidRuntime(1823): at android.os.Handler.dispatchMessage(Handler.java:102)
05-09 10:56:45.812: E/AndroidRuntime(1823): at android.os.Looper.loop(Looper.java:136)
05-09 10:56:45.812: E/AndroidRuntime(1823): at android.app.ActivityThread.main(ActivityThread.java:5017)
05-09 10:56:45.812: E/AndroidRuntime(1823): at java.lang.reflect.Method.invokeNative(Native Method)
05-09 10:56:45.812: E/AndroidRuntime(1823): at java.lang.reflect.Method.invoke(Method.java:515)
05-09 10:56:45.812: E/AndroidRuntime(1823): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
05-09 10:56:45.812: E/AndroidRuntime(1823): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
05-09 10:56:45.812: E/AndroidRuntime(1823): at dalvik.system.NativeStart.main(Native Method)
05-09 10:56:45.812: E/AndroidRuntime(1823): Caused by: java.lang.RuntimeException: Subclasses of PreferenceActivity must override isValidFragment(String) to verify that the Fragment class is valid! com.nextgenintl.aimassistant.PrefsActivity has not checked if fragment com.nextgenintl.aimassistant.SettingsActivity$GeneralPreferenceFragment is valid.
05-09 10:56:45.812: E/AndroidRuntime(1823): at android.preference.PreferenceActivity.isValidFragment(PreferenceActivity.java:898)
05-09 10:56:45.812: E/AndroidRuntime(1823): at android.preference.PreferenceActivity.switchToHeaderInner(PreferenceActivity.java:1179)
05-09 10:56:45.812: E/AndroidRuntime(1823): at android.preference.PreferenceActivity.switchToHeader(PreferenceActivity.java:1219)
05-09 10:56:45.812: E/AndroidRuntime(1823): at android.preference.PreferenceActivity.onCreate(PreferenceActivity.java:564)
05-09 10:56:45.812: E/AndroidRuntime(1823): at com.nextgenintl.aimassistant.PrefsActivity.onCreate(PrefsActivity.java:46)
05-09 10:56:45.812: E/AndroidRuntime(1823): at android.app.Activity.performCreate(Activity.java:5231)
05-09 10:56:45.812: E/AndroidRuntime(1823): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
05-09 10:56:45.812: E/AndroidRuntime(1823): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)
05-09 10:56:45.812: E/AndroidRuntime(1823): ... 11 more
如果您想查看来源：
import android.annotation.TargetApi;
import android.content.Context;
import android.content.res.Configuration;
import android.media.Ringtone;
import android.media.RingtoneManager;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.preference.ListPreference;
import android.preference.Preference;
import android.preference.PreferenceActivity;
import android.preference.PreferenceCategory;
import android.preference.PreferenceFragment;
import android.preference.PreferenceManager;
import android.preference.RingtonePreference;
import android.text.TextUtils;
import android.view.MenuItem;
import android.support.v4.app.NavUtils;
import java.util.List;
/**
* A {@link PreferenceActivity} that presents a set of application settings. On
* handset devices, settings are presented as a single list. On tablets,
* settings are split by category, with category headers shown to the left of
* the list of settings.
* <p>
* See <a href="http://developer.android.com/design/patterns/settings.html">
* Android Design: Settings</a> for design guidelines and the <a
* href="http://developer.android.com/guide/topics/ui/settings.html">Settings
* API Guide</a> for more information on developing a Settings UI.
*/
public class PrefsActivity extends PreferenceActivity {
/**
* Determines whether to always show the simplified settings UI, where
* settings are presented in a single list. When false, settings are shown
* as a master/detail two-pane view on tablets. When true, a single pane is
* shown on tablets.
*/
private static final boolean ALWAYS_SIMPLE_PREFS = false;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setupActionBar();
}
/**
* Set up the {@link android.app.ActionBar}, if the API is available.
*/
@TargetApi(Build.VERSION_CODES.HONEYCOMB)
private void setupActionBar() {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
// Show the Up button in the action bar.
getActionBar().setDisplayHomeAsUpEnabled(true);
}
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == android.R.id.home) {
// This ID represents the Home or Up button. In the case of this
// activity, the Up button is shown. Use NavUtils to allow users
// to navigate up one level in the application structure. For
// more details, see the Navigation pattern on Android Design:
//
// http://developer.android.com/design/patterns/navigation.html#up-vs-back
//
// TODO: If Settings has multiple levels, Up should navigate up
// that hierarchy.
NavUtils.navigateUpFromSameTask(this);
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
protected void onPostCreate(Bundle savedInstanceState) {
super.onPostCreate(savedInstanceState);
setupSimplePreferencesScreen();
}
/**
* Shows the simplified settings UI if the device configuration if the
* device configuration dictates that a simplified, single-pane UI should be
* shown.
*/
private void setupSimplePreferencesScreen() {
if (!isSimplePreferences(this)) {
return;
}
// 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);
// Add 'notifications' preferences, and a corresponding header.
PreferenceCategory fakeHeader = new PreferenceCategory(this);
fakeHeader.setTitle(R.string.pref_header_notifications);
getPreferenceScreen().addPreference(fakeHeader);
addPreferencesFromResource(R.xml.pref_notification);
// Add 'data and sync' preferences, and a corresponding header.
fakeHeader = new PreferenceCategory(this);
fakeHeader.setTitle(R.string.pref_header_data_sync);
getPreferenceScreen().addPreference(fakeHeader);
addPreferencesFromResource(R.xml.pref_data_sync);
// Bind the summaries of EditText/List/Dialog/Ringtone 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"));
bindPreferenceSummaryToValue(findPreference("notifications_new_message_ringtone"));
bindPreferenceSummaryToValue(findPreference("sync_frequency"));
}
/** {@inheritDoc} */
@Override
public boolean onIsMultiPane() {
return isXLargeTablet(this) && !isSimplePreferences(this);
}
/**
* Helper method to determine if the device has an extra-large screen. For
* example, 10" tablets are extra-large.
*/
private static boolean isXLargeTablet(Context context) {
return (context.getResources().getConfiguration().screenLayout & Configuration.SCREENLAYOUT_SIZE_MASK) >= Configuration.SCREENLAYOUT_SIZE_XLARGE;
}
/**
* Determines whether the simplified settings UI should be shown. This is
* true if this is forced via {@link #ALWAYS_SIMPLE_PREFS}, or the device
* doesn't have newer APIs like {@link PreferenceFragment}, or the device
* doesn't have an extra-large screen. In these cases, a single-pane
* "simplified" settings UI should be shown.
*/
private static boolean isSimplePreferences(Context context) {
return ALWAYS_SIMPLE_PREFS
|| Build.VERSION.SDK_INT < Build.VERSION_CODES.HONEYCOMB
|| !isXLargeTablet(context);
}
/** {@inheritDoc} */
@Override
@TargetApi(Build.VERSION_CODES.HONEYCOMB)
public void onBuildHeaders(List<Header> target) {
if (!isSimplePreferences(this)) {
loadHeadersFromResource(R.xml.pref_headers, target);
}
}
/**
* A preference value change listener that updates the preference's summary
* to reflect its new value.
*/
private static Preference.OnPreferenceChangeListener sBindPreferenceSummaryToValueListener = new Preference.OnPreferenceChangeListener() {
@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 if (preference instanceof RingtonePreference) {
// For ringtone preferences, look up the correct display value
// using RingtoneManager.
if (TextUtils.isEmpty(stringValue)) {
// Empty values correspond to 'silent' (no ringtone).
preference.setSummary(R.string.pref_ringtone_silent);
} else {
Ringtone ringtone = RingtoneManager.getRingtone(
preference.getContext(), Uri.parse(stringValue));
if (ringtone == null) {
// Clear the summary if there was a lookup error.
preference.setSummary(null);
} else {
// Set the summary to reflect the new ringtone display
// name.
String name = ringtone
.getTitle(preference.getContext());
preference.setSummary(name);
}
}
} else {
// For all other preferences, set the summary to the value's
// simple string representation.
preference.setSummary(stringValue);
}
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(),
""));
}
/**
* This fragment shows general preferences only. It is used when the
* activity is showing a two-pane settings UI.
*/
@TargetApi(Build.VERSION_CODES.HONEYCOMB)
public static class GeneralPreferenceFragment extends PreferenceFragment {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
addPreferencesFromResource(R.xml.pref_general);
// Bind the summaries of EditText/List/Dialog/Ringtone 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"));
}
}
/**
* This fragment shows notification preferences only. It is used when the
* activity is showing a two-pane settings UI.
*/
@TargetApi(Build.VERSION_CODES.HONEYCOMB)
public static class NotificationPreferenceFragment extends
PreferenceFragment {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
addPreferencesFromResource(R.xml.pref_notification);
// Bind the summaries of EditText/List/Dialog/Ringtone preferences
// to their values. When their values change, their summaries are
// updated to reflect the new value, per the Android Design
// guidelines.
bindPreferenceSummaryToValue(findPreference("notifications_new_message_ringtone"));
}
}
/**
* This fragment shows data and sync preferences only. It is used when the
* activity is showing a two-pane settings UI.
*/
@TargetApi(Build.VERSION_CODES.HONEYCOMB)
public static class DataSyncPreferenceFragment extends PreferenceFragment {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
addPreferencesFromResource(R.xml.pref_data_sync);
// Bind the summaries of EditText/List/Dialog/Ringtone preferences
// to their values. When their values change, their summaries are
// updated to reflect the new value, per the Android Design
// guidelines.
bindPreferenceSummaryToValue(findPreference("sync_frequency"));
}
}
}
XML似乎没有任何错误，因为字符串是在替代文件中生成的（例如string_activity_prefs.xml），并且可以在手机上正常工作。
答案 0 :(得分：0)
Subclasses of PreferenceActivity must override isValidFragment(String) to verify that the Fragment class is valid! com.nextgenintl.aimassistant.PrefsActivity has not checked if fragment com.nextgenintl.aimassistant.SettingsActivity$GeneralPreferenceFragment is valid.
覆盖isValidFragment(String)的{{1}}中的onCreate()。
答案 1 :(得分：0)
您可以在isValidFragment(String)
PreferenceActivity
protected boolean isValidFragment (String fragmentName) {
if(PrefsActivity.class.getName().equals(fragmentName)){
return true;
}
return false;
}
有关详细信息，请阅读此A New Vulnerability in the Android Framework: Fragment Injection