Android SettingsActivity，如何触发BackButton
Android SettingsActivity, how to trigger BackButton
我正在开发的应用程序将 运行 放在平板电脑上，平板电脑将被放置在 "cage" 内，以防止用户删除它。
"cage" 将重新创建 Kiosk 模式； android 带有后退按钮和主页按钮的按钮栏将无法被用户实际访问。
在主要活动和片段中，我设法通过在某些按钮的 OnClickListener 中调用 onBackPressed() "go back"。
现在的问题是我必须添加一个设置 activity，这种 activity 不使用普通布局而是使用 PreferenceScreen。
如果我只能在布局中显示首选项，我不知道如何操作 onBackPressed()。
我尝试添加一个名为 GoBack 的开关首选项并创建一个连续刷新的处理程序并检查 GoBack 首选项是否为 True，在这种情况下我会将其设置为 false 并触发 onBackPressed();但它没有用，返回没有改变，应用程序崩溃了，我无法让它工作。
这是 SettingActivity 代码（android 工作室之一）
public class SettingsActivity extends AppCompatPreferenceActivity {
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;
}
};
/**
* 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;
}
/**
* 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.
try {
sBindPreferenceSummaryToValueListener.onPreferenceChange(preference,
PreferenceManager
.getDefaultSharedPreferences(preference.getContext())
.getString(preference.getKey(), ""));
}
catch (Exception e)
{
try {
sBindPreferenceSummaryToValueListener.onPreferenceChange(preference,
PreferenceManager
.getDefaultSharedPreferences(preference.getContext())
.getBoolean(preference.getKey(),false));
}
catch (Exception ex)
{
Log.e("Impostazioni","Impossibile eseguire Sett.Binding di "+preference.getKey());
}
}
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setupActionBar();
}
/**
* Set up the {@link android.app.ActionBar}, if the API is available.
*/
private void setupActionBar() {
ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
// Show the Up button in the action bar.
actionBar.setDisplayHomeAsUpEnabled(true);
}
}
@Override
public boolean onMenuItemSelected(int featureId, MenuItem item) {
int id = item.getItemId();
if (id == android.R.id.home) {
if (!super.onMenuItemSelected(featureId, item)) {
NavUtils.navigateUpFromSameTask(this);
}
return true;
}
return super.onMenuItemSelected(featureId, item);
}
/**
* {@inheritDoc}
*/
@Override
public boolean onIsMultiPane() {
return isXLargeTablet(this);
}
/**
* {@inheritDoc}
*/
@Override
@TargetApi(Build.VERSION_CODES.HONEYCOMB)
public void onBuildHeaders(List<Header> target) {
loadHeadersFromResource(R.xml.pref_headers, target);
}
/**
* This method stops fragment injection in malicious applications.
* Make sure to deny any unknown fragments here.
*/
protected boolean isValidFragment(String fragmentName) {
return PreferenceFragment.class.getName().equals(fragmentName)
|| GeneralPreferenceFragment.class.getName().equals(fragmentName)
|| DataSyncPreferenceFragment.class.getName().equals(fragmentName)
|| NotificationPreferenceFragment.class.getName().equals(fragmentName);
}
/**
* 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);
setHasOptionsMenu(true);
// 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("PassWordImpostazioni"));
//bindPreferenceSummaryToValue(findPreference("example_list"));
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == android.R.id.home) {
startActivity(new Intent(getActivity(), SettingsActivity.class));
return true;
}
return super.onOptionsItemSelected(item);
}
}
/**
* 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);
setHasOptionsMenu(true);
// 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("LedBattutaPorta"));
bindPreferenceSummaryToValue(findPreference("SpoilerPosteriore"));
bindPreferenceSummaryToValue(findPreference("LuciBianche"));
bindPreferenceSummaryToValue(findPreference("Scalino"));
bindPreferenceSummaryToValue(findPreference("Webasto"));
bindPreferenceSummaryToValue(findPreference("Stufa220V"));*/
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == android.R.id.home) {
startActivity(new Intent(getActivity(), SettingsActivity.class));
return true;
}
return super.onOptionsItemSelected(item);
}
}
/**
* 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);
setHasOptionsMenu(true);
// 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"));
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == android.R.id.home) {
startActivity(new Intent(getActivity(), SettingsActivity.class));
return true;
}
return super.onOptionsItemSelected(item);
}
}
}
这是首选项屏幕XML
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
<PreferenceCategory
android:title="OPT. Luci"
android:key="OptLuci">
<SwitchPreference
android:defaultValue="false"
android:key="LedBattutaPorta"
android:title="Pulsante Disabilitazione Led Battuta Porta" />
<SwitchPreference
android:defaultValue="false"
android:key="SpoilerPosteriore"
android:title="Pulsante Disabilitazione Spoiler Posteriore" />
<SwitchPreference
android:defaultValue="false"
android:key="LuciBianche"
android:title="Pulsante Disabilitazione Luci Bianche" />
</PreferenceCategory>
<PreferenceCategory
android:title="OPT. Servizi"
android:key="OptServizi">
<SwitchPreference
android:defaultValue="false"
android:key="Scalino"
android:title="Pulsante Disabilitazione Scalino" />
</PreferenceCategory>
<PreferenceCategory
android:title="OPT. Clima"
android:key="OptClima">
<SwitchPreference
android:defaultValue="false"
android:key="Webasto"
android:title="Webasto" />
<SwitchPreference
android:defaultValue="false"
android:key="Stufa220V"
android:title="Stufa 220V" />
</PreferenceCategory>
<PreferenceCategory
android:title="OPT. Vano Sanitario"
android:key="OptVanoSanitario">
<SwitchPreference
android:defaultValue="false"
android:key="Bombola1"
android:title="Presenza Bombola 1" />
<SwitchPreference
android:defaultValue="false"
android:key="Bombola2"
android:title="Presenza Bombola 2" />
</PreferenceCategory>
您可以保留一个按钮并在单击该按钮时调用：
finishActivity();
这将在您的 activity 堆栈中强制 return 到上一个 activity。
1.Back Activity
中的按钮
从
复制布局
com.android.internal.R.layout.preference_list_content_single
添加后退按钮并覆盖 onCreate 以设置新布局
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(yourLayout)
}
2.Back 片段布局中的按钮
从
复制布局
com.android.internal.R.layout.preference_list_fragment
并添加您的后退按钮
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container,
@Nullable Bundle savedInstanceState) {
TypedArray a = getActivity().obtainStyledAttributes(null,
com.android.internal.R.styleable.PreferenceFragment,
com.android.internal.R.attr.preferenceFragmentStyle,
0);
int yourLayout = R.layout.your_layout; //put your custom layout here
yourLayout = a.getResourceId(com.android.internal.R.styleable.PreferenceFragment_layout,
yourLayout);
a.recycle();
return inflater.inflate(yourLayout, container, false);
}
向按钮注册一个 OnClickListener 并调用 Activity 的 onBackPressed() 将触发后退操作（finish() 将销毁 activity，如果您需要，这可能没有用导航回较早的片段）
编辑：我还没有测试过，但它应该可以工作
这样解决的问题：
我制作了另一个自定义主题，仅用于显示带有后退按钮的操作栏的设置。
它工作正常，感谢大家:)
我正在开发的应用程序将 运行 放在平板电脑上，平板电脑将被放置在 "cage" 内，以防止用户删除它。 "cage" 将重新创建 Kiosk 模式； android 带有后退按钮和主页按钮的按钮栏将无法被用户实际访问。
在主要活动和片段中，我设法通过在某些按钮的 OnClickListener 中调用 onBackPressed() "go back"。
现在的问题是我必须添加一个设置 activity，这种 activity 不使用普通布局而是使用 PreferenceScreen。
如果我只能在布局中显示首选项，我不知道如何操作 onBackPressed()。
我尝试添加一个名为 GoBack 的开关首选项并创建一个连续刷新的处理程序并检查 GoBack 首选项是否为 True，在这种情况下我会将其设置为 false 并触发 onBackPressed();但它没有用，返回没有改变，应用程序崩溃了，我无法让它工作。
这是 SettingActivity 代码（android 工作室之一）
public class SettingsActivity extends AppCompatPreferenceActivity {
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;
}
};
/**
* 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;
}
/**
* 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.
try {
sBindPreferenceSummaryToValueListener.onPreferenceChange(preference,
PreferenceManager
.getDefaultSharedPreferences(preference.getContext())
.getString(preference.getKey(), ""));
}
catch (Exception e)
{
try {
sBindPreferenceSummaryToValueListener.onPreferenceChange(preference,
PreferenceManager
.getDefaultSharedPreferences(preference.getContext())
.getBoolean(preference.getKey(),false));
}
catch (Exception ex)
{
Log.e("Impostazioni","Impossibile eseguire Sett.Binding di "+preference.getKey());
}
}
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setupActionBar();
}
/**
* Set up the {@link android.app.ActionBar}, if the API is available.
*/
private void setupActionBar() {
ActionBar actionBar = getSupportActionBar();
if (actionBar != null) {
// Show the Up button in the action bar.
actionBar.setDisplayHomeAsUpEnabled(true);
}
}
@Override
public boolean onMenuItemSelected(int featureId, MenuItem item) {
int id = item.getItemId();
if (id == android.R.id.home) {
if (!super.onMenuItemSelected(featureId, item)) {
NavUtils.navigateUpFromSameTask(this);
}
return true;
}
return super.onMenuItemSelected(featureId, item);
}
/**
* {@inheritDoc}
*/
@Override
public boolean onIsMultiPane() {
return isXLargeTablet(this);
}
/**
* {@inheritDoc}
*/
@Override
@TargetApi(Build.VERSION_CODES.HONEYCOMB)
public void onBuildHeaders(List<Header> target) {
loadHeadersFromResource(R.xml.pref_headers, target);
}
/**
* This method stops fragment injection in malicious applications.
* Make sure to deny any unknown fragments here.
*/
protected boolean isValidFragment(String fragmentName) {
return PreferenceFragment.class.getName().equals(fragmentName)
|| GeneralPreferenceFragment.class.getName().equals(fragmentName)
|| DataSyncPreferenceFragment.class.getName().equals(fragmentName)
|| NotificationPreferenceFragment.class.getName().equals(fragmentName);
}
/**
* 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);
setHasOptionsMenu(true);
// 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("PassWordImpostazioni"));
//bindPreferenceSummaryToValue(findPreference("example_list"));
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == android.R.id.home) {
startActivity(new Intent(getActivity(), SettingsActivity.class));
return true;
}
return super.onOptionsItemSelected(item);
}
}
/**
* 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);
setHasOptionsMenu(true);
// 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("LedBattutaPorta"));
bindPreferenceSummaryToValue(findPreference("SpoilerPosteriore"));
bindPreferenceSummaryToValue(findPreference("LuciBianche"));
bindPreferenceSummaryToValue(findPreference("Scalino"));
bindPreferenceSummaryToValue(findPreference("Webasto"));
bindPreferenceSummaryToValue(findPreference("Stufa220V"));*/
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == android.R.id.home) {
startActivity(new Intent(getActivity(), SettingsActivity.class));
return true;
}
return super.onOptionsItemSelected(item);
}
}
/**
* 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);
setHasOptionsMenu(true);
// 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"));
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == android.R.id.home) {
startActivity(new Intent(getActivity(), SettingsActivity.class));
return true;
}
return super.onOptionsItemSelected(item);
}
}
}
这是首选项屏幕XML
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
<PreferenceCategory
android:title="OPT. Luci"
android:key="OptLuci">
<SwitchPreference
android:defaultValue="false"
android:key="LedBattutaPorta"
android:title="Pulsante Disabilitazione Led Battuta Porta" />
<SwitchPreference
android:defaultValue="false"
android:key="SpoilerPosteriore"
android:title="Pulsante Disabilitazione Spoiler Posteriore" />
<SwitchPreference
android:defaultValue="false"
android:key="LuciBianche"
android:title="Pulsante Disabilitazione Luci Bianche" />
</PreferenceCategory>
<PreferenceCategory
android:title="OPT. Servizi"
android:key="OptServizi">
<SwitchPreference
android:defaultValue="false"
android:key="Scalino"
android:title="Pulsante Disabilitazione Scalino" />
</PreferenceCategory>
<PreferenceCategory
android:title="OPT. Clima"
android:key="OptClima">
<SwitchPreference
android:defaultValue="false"
android:key="Webasto"
android:title="Webasto" />
<SwitchPreference
android:defaultValue="false"
android:key="Stufa220V"
android:title="Stufa 220V" />
</PreferenceCategory>
<PreferenceCategory
android:title="OPT. Vano Sanitario"
android:key="OptVanoSanitario">
<SwitchPreference
android:defaultValue="false"
android:key="Bombola1"
android:title="Presenza Bombola 1" />
<SwitchPreference
android:defaultValue="false"
android:key="Bombola2"
android:title="Presenza Bombola 2" />
</PreferenceCategory>
您可以保留一个按钮并在单击该按钮时调用：
finishActivity();
这将在您的 activity 堆栈中强制 return 到上一个 activity。
1.Back Activity
中的按钮从
复制布局com.android.internal.R.layout.preference_list_content_single
添加后退按钮并覆盖 onCreate 以设置新布局
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(yourLayout)
}
2.Back 片段布局中的按钮
从
复制布局com.android.internal.R.layout.preference_list_fragment
并添加您的后退按钮
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container,
@Nullable Bundle savedInstanceState) {
TypedArray a = getActivity().obtainStyledAttributes(null,
com.android.internal.R.styleable.PreferenceFragment,
com.android.internal.R.attr.preferenceFragmentStyle,
0);
int yourLayout = R.layout.your_layout; //put your custom layout here
yourLayout = a.getResourceId(com.android.internal.R.styleable.PreferenceFragment_layout,
yourLayout);
a.recycle();
return inflater.inflate(yourLayout, container, false);
}
向按钮注册一个 OnClickListener 并调用 Activity 的 onBackPressed() 将触发后退操作（finish() 将销毁 activity，如果您需要，这可能没有用导航回较早的片段）
编辑：我还没有测试过，但它应该可以工作
这样解决的问题：
我制作了另一个自定义主题，仅用于显示带有后退按钮的操作栏的设置。
它工作正常，感谢大家:)