Preference
public
class
Preference
extends Object
implements
Comparable<Preference>
java.lang.Object | |
↳ | android.preference.Preference |
Represents the basic Preference UI building
block displayed by a PreferenceActivity
in the form of a
ListView
. This class provides the View
to be displayed in
the activity and associates with a SharedPreferences
to
store/retrieve the preference data.
When specifying a preference hierarchy in XML, each element can point to a
subclass of Preference
, similar to the view hierarchy and layouts.
This class contains a key
that will be used as the key into the
SharedPreferences
. It is up to the subclass to decide how to store
the value.
Developer Guides
For information about building a settings UI with Preferences, read the Settings guide.
Summary
Nested classes | |
---|---|
class |
Preference.BaseSavedState
A base class for managing the instance state of a |
interface |
Preference.OnPreferenceChangeListener
Interface definition for a callback to be invoked when the value of this
|
interface |
Preference.OnPreferenceClickListener
Interface definition for a callback to be invoked when a |
XML attributes | |
---|---|
android:defaultValue |
The default value for the preference, which will be set either if persistence is off or persistence is on and the preference is not found in the persistent storage. |
android:dependency |
The key of another Preference that this Preference will depend on. |
android:enabled |
Whether the Preference is enabled. |
android:fragment |
When used inside of a modern PreferenceActivity, this declares a new PreferenceFragment to be shown when the user selects this item. |
android:icon |
The optional icon for the preference. |
android:iconSpaceReserved |
Whether the space for the preference icon view will be reserved. |
android:key |
The key to store the Preference value. |
android:layout |
The layout for the Preference in a PreferenceActivity screen. |
android:order |
The order for the Preference (lower values are to be ordered first). |
android:persistent |
Whether the Preference stores its value to the storage. |
android:recycleEnabled |
Whether the preference has enabled to have its view recycled when used in the list view. |
android:selectable |
Whether the Preference is selectable. |
android:shouldDisableView |
Whether the view of this Preference should be disabled when this Preference is disabled. |
android:singleLineTitle |
Whether to use single line for the preference title text. |
android:summary |
The summary for the Preference. |
android:title |
The title for the Preference. |
android:widgetLayout |
The layout for the controllable widget portion of a Preference. |
Constants | |
---|---|
int |
DEFAULT_ORDER
Specify for |
Public constructors | |
---|---|
Preference(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes)
Perform inflation from XML and apply a class-specific base style. |
|
Preference(Context context, AttributeSet attrs, int defStyleAttr)
Perform inflation from XML and apply a class-specific base style. |
|
Preference(Context context, AttributeSet attrs)
Constructor that is called when inflating a Preference from XML. |
|
Preference(Context context)
Constructor to create a Preference. |
Public methods | |
---|---|
int
|
compareTo(Preference another)
Compares Preference objects based on order (if set), otherwise alphabetically on the titles. |
Context
|
getContext()
Returns the |
String
|
getDependency()
Returns the key of the dependency on this Preference. |
SharedPreferences.Editor
|
getEditor()
Returns an |
Bundle
|
getExtras()
Return the extras Bundle object associated with this preference, creating a new Bundle if there currently isn't one. |
String
|
getFragment()
Return the fragment class name associated with this Preference. |
Drawable
|
getIcon()
Returns the icon of this Preference. |
Intent
|
getIntent()
Return the |
String
|
getKey()
Gets the key for this Preference, which is also the key used for storing values into
|
int
|
getLayoutResource()
Gets the layout resource that will be shown as the |
Preference.OnPreferenceChangeListener
|
getOnPreferenceChangeListener()
Returns the callback to be invoked when this Preference is changed by the user (but before the internal state has been updated). |
Preference.OnPreferenceClickListener
|
getOnPreferenceClickListener()
Returns the callback to be invoked when this Preference is clicked. |
int
|
getOrder()
Gets the order of this Preference with respect to other Preference objects on the same level. |
PreferenceGroup
|
getParent()
Returns the |
Set<String>
|
getPersistedStringSet(Set<String> defaultReturnValue)
Attempts to get a persisted set of Strings if this Preference is persistent. |
PreferenceDataStore
|
getPreferenceDataStore()
Returns |
PreferenceManager
|
getPreferenceManager()
Gets the |
SharedPreferences
|
getSharedPreferences()
Returns the |
boolean
|
getShouldDisableView()
Checks whether this Preference should disable its view when it's action is disabled. |
CharSequence
|
getSummary()
Returns the summary of this Preference. |
CharSequence
|
getTitle()
Returns the title of this Preference. |
int
|
getTitleRes()
Returns the title resource ID of this Preference. |
View
|
getView(View convertView, ViewGroup parent)
Gets the View that will be shown in the |
int
|
getWidgetLayoutResource()
Gets the layout resource for the controllable widget portion of this Preference. |
boolean
|
hasKey()
Checks whether this Preference has a valid key. |
boolean
|
isEnabled()
Checks whether this Preference should be enabled in the list. |
boolean
|
isIconSpaceReserved()
Gets whether the space this preference icon view is reserved. |
boolean
|
isPersistent()
Checks whether this Preference is persistent. |
boolean
|
isRecycleEnabled()
Checks whether this Preference has enabled to have its view recycled when used in the list view. |
boolean
|
isSelectable()
Checks whether this Preference should be selectable in the list. |
boolean
|
isSingleLineTitle()
Gets whether the title of this preference is constrained to a single line. |
void
|
notifyDependencyChange(boolean disableDependents)
Notifies any listening dependents of a change that affects the dependency. |
void
|
onDependencyChanged(Preference dependency, boolean disableDependent)
Called when the dependency changes. |
void
|
onParentChanged(Preference parent, boolean disableChild)
Called when the implicit parent dependency changes. |
Bundle
|
peekExtras()
Return the extras Bundle object associated with this preference, returning |
boolean
|
persistStringSet(Set<String> values)
Attempts to persist a set of Strings if this Preference is persistent. |
void
|
restoreHierarchyState(Bundle container)
Restore this Preference hierarchy's previously saved state from the given container. |
void
|
saveHierarchyState(Bundle container)
Store this Preference hierarchy's frozen state into the given container. |
void
|
setDefaultValue(Object defaultValue)
Sets the default value for this Preference, which will be set either if persistence is off or persistence is on and the preference is not found in the persistent storage. |
void
|
setDependency(String dependencyKey)
Sets the key of a Preference that this Preference will depend on. |
void
|
setEnabled(boolean enabled)
Sets whether this Preference is enabled. |
void
|
setFragment(String fragment)
Sets the class name of a fragment to be shown when this Preference is clicked. |
void
|
setIcon(Drawable icon)
Sets the icon for this Preference with a Drawable. |
void
|
setIcon(int iconResId)
Sets the icon for this Preference with a resource ID. |
void
|
setIconSpaceReserved(boolean iconSpaceReserved)
Sets whether to reserve the space of this Preference icon view when no icon is provided. |
void
|
setIntent(Intent intent)
Sets an |
void
|
setKey(String key)
Sets the key for this Preference, which is used as a key to the |
void
|
setLayoutResource(int layoutResId)
Sets the layout resource that is inflated as the |
void
|
setOnPreferenceChangeListener(Preference.OnPreferenceChangeListener onPreferenceChangeListener)
Sets the callback to be invoked when this Preference is changed by the user (but before the internal state has been updated). |
void
|
setOnPreferenceClickListener(Preference.OnPreferenceClickListener onPreferenceClickListener)
Sets the callback to be invoked when this Preference is clicked. |
void
|
setOrder(int order)
Sets the order of this Preference with respect to other Preference objects on the same level. |
void
|
setPersistent(boolean persistent)
Sets whether this Preference is persistent. |
void
|
setPreferenceDataStore(PreferenceDataStore dataStore)
Sets a |
void
|
setRecycleEnabled(boolean enabled)
Sets whether this Preference has enabled to have its view recycled when used in the list view. |
void
|
setSelectable(boolean selectable)
Sets whether this Preference is selectable. |
void
|
setShouldDisableView(boolean shouldDisableView)
Sets whether this Preference should disable its view when it gets disabled. |
void
|
setSingleLineTitle(boolean singleLineTitle)
Sets whether to constrain the title of this Preference to a single line instead of letting it wrap onto multiple lines. |
void
|
setSummary(CharSequence summary)
Sets the summary for this Preference with a CharSequence. |
void
|
setSummary(int summaryResId)
Sets the summary for this Preference with a resource ID. |
void
|
setTitle(CharSequence title)
Sets the title for this Preference with a CharSequence. |
void
|
setTitle(int titleResId)
Sets the title for this Preference with a resource ID. |
void
|
setWidgetLayoutResource(int widgetLayoutResId)
Sets the layout for the controllable widget portion of this Preference. |
boolean
|
shouldCommit()
Returns whether the |
boolean
|
shouldDisableDependents()
Checks whether this preference's dependents should currently be disabled. |
String
|
toString()
Returns a string representation of the object. |
Protected methods | |
---|---|
boolean
|
callChangeListener(Object newValue)
Call this method after the user changes the preference, but before the internal state is set. |
Preference
|
findPreferenceInHierarchy(String key)
Finds a Preference in this hierarchy (the whole thing,
even above/below your |
boolean
|
getPersistedBoolean(boolean defaultReturnValue)
Attempts to get a persisted boolean if this Preference is persistent. |
float
|
getPersistedFloat(float defaultReturnValue)
Attempts to get a persisted float if this Preference is persistent. |
int
|
getPersistedInt(int defaultReturnValue)
Attempts to get a persisted int if this Preference is persistent. |
long
|
getPersistedLong(long defaultReturnValue)
Attempts to get a persisted long if this Preference is persistent. |
String
|
getPersistedString(String defaultReturnValue)
Attempts to get a persisted String if this Preference is persistent. |
void
|
notifyChanged()
Should be called when the data of this |
void
|
notifyHierarchyChanged()
Should be called when a Preference has been added/removed from this group, or the ordering should be re-evaluated. |
void
|
onAttachedToActivity()
Called when the Preference hierarchy has been attached to the
|
void
|
onAttachedToHierarchy(PreferenceManager preferenceManager)
Called when this Preference has been attached to a Preference hierarchy. |
void
|
onBindView(View view)
Binds the created View to the data for this Preference. |
void
|
onClick()
Processes a click on the preference. |
View
|
onCreateView(ViewGroup parent)
Creates the View to be shown for this Preference in the
|
Object
|
onGetDefaultValue(TypedArray a, int index)
Called when a Preference is being inflated and the default value attribute needs to be read. |
void
|
onPrepareForRemoval()
Called when this Preference is being removed from the hierarchy. |
void
|
onRestoreInstanceState(Parcelable state)
Hook allowing a Preference to re-apply a representation of its internal state that had
previously been generated by |
Parcelable
|
onSaveInstanceState()
Hook allowing a Preference to generate a representation of its internal state that can later be used to create a new instance with that same state. |
void
|
onSetInitialValue(boolean restorePersistedValue, Object defaultValue)
Implement this to set the initial value of the Preference. |
boolean
|
persistBoolean(boolean value)
Attempts to persist a boolean if this Preference is persistent. |
boolean
|
persistFloat(float value)
Attempts to persist a long if this Preference is persistent. |
boolean
|
persistInt(int value)
Attempts to persist an int if this Preference is persistent. |
boolean
|
persistLong(long value)
Attempts to persist a long if this Preference is persistent. |
boolean
|
persistString(String value)
Attempts to persist a String if this Preference is persistent. |
boolean
|
shouldPersist()
Checks whether, at the given time this method is called, this Preference should store/restore
its value(s) into the |
Inherited methods | |
---|---|
XML attributes
android:defaultValue
The default value for the preference, which will be set either if persistence is off or persistence is on and the preference is not found in the persistent storage.
May be a reference to another resource, in the form
"@[+][package:]type/name
" or a theme
attribute in the form
"?[package:]type/name
".
May be a string value, using '\\;' to escape characters such as '\\n' or '\\uxxxx' for a unicode character;
May be an integer value, such as "100
".
May be a boolean value, such as "true
" or
"false
".
May be a floating point value, such as "1.2
".
android:dependency
The key of another Preference that this Preference will depend on. If the other Preference is not set or is off, this Preference will be disabled.
May be a string value, using '\\;' to escape characters such as '\\n' or '\\uxxxx' for a unicode character;
android:enabled
Whether the Preference is enabled.
May be a boolean value, such as "true
" or
"false
".
android:fragment
When used inside of a modern PreferenceActivity, this declares a new PreferenceFragment to be shown when the user selects this item.
May be a string value, using '\\;' to escape characters such as '\\n' or '\\uxxxx' for a unicode character;
android:icon
The optional icon for the preference.
May be a reference to another resource, in the form
"@[+][package:]type/name
" or a theme
attribute in the form
"?[package:]type/name
".
android:iconSpaceReserved
Whether the space for the preference icon view will be reserved. By default, preference icon view visibility will be set to GONE when there is no icon provided, so the default value of this attribute is false.
May be a boolean value, such as "true
" or
"false
".
android:key
The key to store the Preference value.
May be a string value, using '\\;' to escape characters such as '\\n' or '\\uxxxx' for a unicode character;
android:layout
The layout for the Preference in a PreferenceActivity screen. This should rarely need to be changed, look at widgetLayout instead.
May be a reference to another resource, in the form
"@[+][package:]type/name
" or a theme
attribute in the form
"?[package:]type/name
".
android:order
The order for the Preference (lower values are to be ordered first). If this is not specified, the default ordering will be alphabetic.
May be an integer value, such as "100
".
android:persistent
Whether the Preference stores its value to the storage.
May be a boolean value, such as "true
" or
"false
".
android:recycleEnabled
Whether the preference has enabled to have its view recycled when used in the list view. This is true by default.
May be a boolean value, such as "true
" or
"false
".
android:selectable
Whether the Preference is selectable.
May be a boolean value, such as "true
" or
"false
".
android:shouldDisableView
Whether the view of this Preference should be disabled when this Preference is disabled.
May be a boolean value, such as "true
" or
"false
".
android:singleLineTitle
Whether to use single line for the preference title text. By default, preference title will be constrained to one line, so the default value of this attribute is true.
May be a boolean value, such as "true
" or
"false
".
android:summary
The summary for the Preference. In API 25 and earlier, this value is read as a plain string with styling information stripped.
May be a string value, using '\\;' to escape characters such as '\\n' or '\\uxxxx' for a unicode character;
android:title
The title for the Preference. In API 25 and earlier, this value is read as a plain string with styling information stripped.
May be a string value, using '\\;' to escape characters such as '\\n' or '\\uxxxx' for a unicode character;
android:widgetLayout
The layout for the controllable widget portion of a Preference. This is inflated into the layout for a Preference and should be used more frequently than the layout attribute. For example, a checkbox preference would specify a custom layout (consisting of just the CheckBox) here.
May be a reference to another resource, in the form
"@[+][package:]type/name
" or a theme
attribute in the form
"?[package:]type/name
".
Constants
DEFAULT_ORDER
int DEFAULT_ORDER
Specify for setOrder(int)
if a specific order is not required.
Constant Value: 2147483647 (0x7fffffff)
Public constructors
Preference
Preference (Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes)
Perform inflation from XML and apply a class-specific base style. This
constructor of Preference allows subclasses to use their own base style
when they are inflating. For example, a CheckBoxPreference
constructor calls this version of the super class constructor and
supplies android.R.attr.checkBoxPreferenceStyle
for
defStyleAttr. This allows the theme's checkbox preference
style to modify all of the base preference attributes as well as the
CheckBoxPreference
class's attributes.
Parameters | |
---|---|
context |
Context : The Context this is associated with, through which it can
access the current theme, resources,
SharedPreferences , etc. |
attrs |
AttributeSet : The attributes of the XML tag that is inflating the
preference. |
defStyleAttr |
int : An attribute in the current theme that contains a
reference to a style resource that supplies default values for
the view. Can be 0 to not look for defaults. |
defStyleRes |
int : A resource identifier of a style resource that
supplies default values for the view, used only if
defStyleAttr is 0 or can not be found in the theme. Can be 0
to not look for defaults. |
See also:
Preference
Preference (Context context, AttributeSet attrs, int defStyleAttr)
Perform inflation from XML and apply a class-specific base style. This
constructor of Preference allows subclasses to use their own base style
when they are inflating. For example, a CheckBoxPreference
constructor calls this version of the super class constructor and
supplies android.R.attr.checkBoxPreferenceStyle
for
defStyleAttr. This allows the theme's checkbox preference
style to modify all of the base preference attributes as well as the
CheckBoxPreference
class's attributes.
Parameters | |
---|---|
context |
Context : The Context this is associated with, through which it can
access the current theme, resources,
SharedPreferences , etc. |
attrs |
AttributeSet : The attributes of the XML tag that is inflating the
preference. |
defStyleAttr |
int : An attribute in the current theme that contains a
reference to a style resource that supplies default values for
the view. Can be 0 to not look for defaults. |
See also:
Preference
Preference (Context context, AttributeSet attrs)
Constructor that is called when inflating a Preference from XML. This is called when a Preference is being constructed from an XML file, supplying attributes that were specified in the XML file. This version uses a default style of 0, so the only attribute values applied are those in the Context's Theme and the given AttributeSet.
Parameters | |
---|---|
context |
Context : The Context this is associated with, through which it can
access the current theme, resources, SharedPreferences ,
etc. |
attrs |
AttributeSet : The attributes of the XML tag that is inflating the
preference. |
See also:
Preference
Preference (Context context)
Constructor to create a Preference.
Parameters | |
---|---|
context |
Context : The Context in which to store Preference values.
|
Public methods
compareTo
int compareTo (Preference another)
Compares Preference objects based on order (if set), otherwise alphabetically on the titles.
Parameters | |
---|---|
another |
Preference : The Preference to compare to this one. |
Returns | |
---|---|
int |
0 if the same; less than 0 if this Preference sorts ahead of another; greater than 0 if this Preference sorts after another. |
getContext
Context getContext ()
Returns the Context
of this Preference.
Each Preference in a Preference hierarchy can be
from different Context (for example, if multiple activities provide preferences into a single
PreferenceActivity
). This Context will be used to save the Preference values.
Returns | |
---|---|
Context |
The Context of this Preference. |
getDependency
String getDependency ()
Returns the key of the dependency on this Preference.
Returns | |
---|---|
String |
The key of the dependency. |
See also:
getEditor
SharedPreferences.Editor getEditor ()
Returns an SharedPreferences.Editor
where this Preference can
save its value(s). Usually it's easier to use one of the helper save
methods: persistBoolean(boolean)
, persistFloat(float)
,
persistInt(int)
, persistLong(long)
,
persistString(String)
. To read values, see
getSharedPreferences()
. If shouldCommit()
returns
true, it is this Preference's responsibility to commit.
In some cases, writes to this will not be committed right away and hence not show up in the SharedPreferences, this is intended behavior to improve performance.
Returns | |
---|---|
SharedPreferences.Editor |
a SharedPreferences.Editor where this preference saves its value(s). If
this preference isn't attached to a Preference hierarchy or if
a PreferenceDataStore has been set, this method returns null . |
getExtras
Bundle getExtras ()
Return the extras Bundle object associated with this preference, creating a new Bundle if there currently isn't one. You can use this to get and set individual extra key/value pairs.
Returns | |
---|---|
Bundle |
getFragment
String getFragment ()
Return the fragment class name associated with this Preference.
Returns | |
---|---|
String |
The fragment class name last set via setFragment(String) or XML.
|
getIcon
Drawable getIcon ()
Returns the icon of this Preference.
Returns | |
---|---|
Drawable |
the icon |
See also:
getIntent
Intent getIntent ()
Return the Intent
associated with this Preference.
Returns | |
---|---|
Intent |
The Intent last set via setIntent(Intent) or XML.
|
getKey
String getKey ()
Gets the key for this Preference, which is also the key used for storing values into
SharedPreferences
or PreferenceDataStore
.
Returns | |
---|---|
String |
The key. |
getLayoutResource
int getLayoutResource ()
Gets the layout resource that will be shown as the View
for this Preference.
Returns | |
---|---|
int |
The layout resource ID. |
getOnPreferenceChangeListener
Preference.OnPreferenceChangeListener getOnPreferenceChangeListener ()
Returns the callback to be invoked when this Preference is changed by the user (but before the internal state has been updated).
Returns | |
---|---|
Preference.OnPreferenceChangeListener |
The callback to be invoked. |
getOnPreferenceClickListener
Preference.OnPreferenceClickListener getOnPreferenceClickListener ()
Returns the callback to be invoked when this Preference is clicked.
Returns | |
---|---|
Preference.OnPreferenceClickListener |
The callback to be invoked. |
getOrder
int getOrder ()
Gets the order of this Preference with respect to other Preference objects on the same level.
Returns | |
---|---|
int |
the order of this Preference |
See also:
getParent
PreferenceGroup getParent ()
Returns the PreferenceGroup
which is this Preference assigned to or null
if
this preference is not assigned to any group or is a root Preference.
Returns | |
---|---|
PreferenceGroup |
the parent PreferenceGroup or null if not attached to any
|
getPersistedStringSet
Set<String> getPersistedStringSet (Set<String> defaultReturnValue)
Attempts to get a persisted set of Strings if this Preference is persistent.
Parameters | |
---|---|
defaultReturnValue |
Set : The default value to return if either this
Preference is not persistent or this Preference is not present. |
Returns | |
---|---|
Set<String> |
The value from the data store or the default return value. |
See also:
getPreferenceDataStore
PreferenceDataStore getPreferenceDataStore ()
Returns PreferenceDataStore
used by this Preference. Returns null
if
SharedPreferences
is used instead.
By default preferences always use SharedPreferences
. To make this
preference to use the PreferenceDataStore
you need to assign your implementation
to the Preference itself via setPreferenceDataStore(PreferenceDataStore)
or to its
PreferenceManager
via
setPreferenceDataStore(PreferenceDataStore)
.
Returns | |
---|---|
PreferenceDataStore |
The PreferenceDataStore used by this Preference or null if none.
|
getPreferenceManager
PreferenceManager getPreferenceManager ()
Gets the PreferenceManager
that manages this Preference object's tree.
Returns | |
---|---|
PreferenceManager |
The PreferenceManager .
|
getSharedPreferences
SharedPreferences getSharedPreferences ()
Returns the SharedPreferences
where this Preference can read its
value(s). Usually, it's easier to use one of the helper read methods:
getPersistedBoolean(boolean)
, getPersistedFloat(float)
,
getPersistedInt(int)
, getPersistedLong(long)
,
getPersistedString(String)
. To save values, see
getEditor()
.
In some cases, writes to the getEditor()
will not be committed
right away and hence not show up in the returned
SharedPreferences
, this is intended behavior to improve
performance.
Returns | |
---|---|
SharedPreferences |
the SharedPreferences where this Preference reads its value(s). If
this preference isn't attached to a Preference hierarchy or if
a PreferenceDataStore has been set, this method returns null . |
getShouldDisableView
boolean getShouldDisableView ()
Checks whether this Preference should disable its view when it's action is disabled.
Returns | |
---|---|
boolean |
true if it should disable the view
|
See also:
getSummary
CharSequence getSummary ()
Returns the summary of this Preference.
Returns | |
---|---|
CharSequence |
the summary |
See also:
getTitle
CharSequence getTitle ()
Returns the title of this Preference.
Returns | |
---|---|
CharSequence |
the title |
See also:
getTitleRes
int getTitleRes ()
Returns the title resource ID of this Preference. If the title did not come from a resource,
0
is returned.
Returns | |
---|---|
int |
the title resource |
See also:
getView
View getView (View convertView, ViewGroup parent)
Gets the View that will be shown in the PreferenceActivity
.
Parameters | |
---|---|
convertView |
View : The old View to reuse, if possible. Note: You should
check that this View is non-null and of an appropriate type
before using. If it is not possible to convert this View to
display the correct data, this method can create a new View. |
parent |
ViewGroup : The parent that this View will eventually be attached to. |
Returns | |
---|---|
View |
Returns the same Preference object, for chaining multiple calls into a single statement. |
See also:
getWidgetLayoutResource
int getWidgetLayoutResource ()
Gets the layout resource for the controllable widget portion of this Preference.
Returns | |
---|---|
int |
The layout resource ID. |
hasKey
boolean hasKey ()
Checks whether this Preference has a valid key.
Returns | |
---|---|
boolean |
True if the key exists and is not a blank string, false otherwise. |
isEnabled
boolean isEnabled ()
Checks whether this Preference should be enabled in the list.
Returns | |
---|---|
boolean |
true if this Preference is enabled, false otherwise
|
isIconSpaceReserved
boolean isIconSpaceReserved ()
Gets whether the space this preference icon view is reserved.
Returns | |
---|---|
boolean |
true if the space of this preference icon view is reserved
|
See also:
isPersistent
boolean isPersistent ()
Checks whether this Preference is persistent. If it is, it stores its value(s) into
the persistent SharedPreferences
storage by default or into
PreferenceDataStore
if assigned.
Returns | |
---|---|
boolean |
True if it is persistent. |
isRecycleEnabled
boolean isRecycleEnabled ()
Checks whether this Preference has enabled to have its view recycled when used in the list view.
Returns | |
---|---|
boolean |
true if this preference view should be recycled
|
See also:
isSelectable
boolean isSelectable ()
Checks whether this Preference should be selectable in the list.
Returns | |
---|---|
boolean |
true if it is selectable, false otherwise
|
isSingleLineTitle
boolean isSingleLineTitle ()
Gets whether the title of this preference is constrained to a single line.
Returns | |
---|---|
boolean |
true if the title of this preference is constrained to a single line
|
See also:
notifyDependencyChange
void notifyDependencyChange (boolean disableDependents)
Notifies any listening dependents of a change that affects the dependency.
Parameters | |
---|---|
disableDependents |
boolean : Whether this Preference should disable
its dependents.
|
onDependencyChanged
void onDependencyChanged (Preference dependency, boolean disableDependent)
Called when the dependency changes.
Parameters | |
---|---|
dependency |
Preference : The Preference that this Preference depends on. |
disableDependent |
boolean : Set true to disable this Preference.
|
onParentChanged
void onParentChanged (Preference parent, boolean disableChild)
Called when the implicit parent dependency changes.
Parameters | |
---|---|
parent |
Preference : The Preference that this Preference depends on. |
disableChild |
boolean : Set true to disable this Preference.
|
peekExtras
Bundle peekExtras ()
Return the extras Bundle object associated with this preference, returning null
if
there is not currently one.
Returns | |
---|---|
Bundle |
persistStringSet
boolean persistStringSet (Set<String> values)
Attempts to persist a set of Strings if this Preference is persistent.
Parameters | |
---|---|
values |
Set : The values to persist. |
Returns | |
---|---|
boolean |
True if this Preference is persistent. (This is not whether the value was persisted, since we may not necessarily commit if there will be a batch commit later.) |
See also:
restoreHierarchyState
void restoreHierarchyState (Bundle container)
Restore this Preference hierarchy's previously saved state from the given container.
Parameters | |
---|---|
container |
Bundle : The Bundle that holds the previously saved state. |
saveHierarchyState
void saveHierarchyState (Bundle container)
Store this Preference hierarchy's frozen state into the given container.
Parameters | |
---|---|
container |
Bundle : The Bundle in which to save the instance of this Preference. |
setDefaultValue
void setDefaultValue (Object defaultValue)
Sets the default value for this Preference, which will be set either if persistence is off or persistence is on and the preference is not found in the persistent storage.
Parameters | |
---|---|
defaultValue |
Object : The default value.
|
setDependency
void setDependency (String dependencyKey)
Sets the key of a Preference that this Preference will depend on. If that Preference is not set or is off, this Preference will be disabled.
Parameters | |
---|---|
dependencyKey |
String : The key of the Preference that this depends on.
|
setEnabled
void setEnabled (boolean enabled)
Sets whether this Preference is enabled. If disabled, it will not handle clicks.
Parameters | |
---|---|
enabled |
boolean : set true to enable it
|
setFragment
void setFragment (String fragment)
Sets the class name of a fragment to be shown when this Preference is clicked.
Parameters | |
---|---|
fragment |
String : The class name of the fragment associated with this Preference.
|
setIcon
void setIcon (Drawable icon)
Sets the icon for this Preference with a Drawable. This icon will be placed into the ID
icon
within the View created by onCreateView(ViewGroup)
.
Parameters | |
---|---|
icon |
Drawable : the optional icon for this Preference
|
setIcon
void setIcon (int iconResId)
Sets the icon for this Preference with a resource ID.
Parameters | |
---|---|
iconResId |
int : the icon as a resource ID
|
See also:
setIconSpaceReserved
void setIconSpaceReserved (boolean iconSpaceReserved)
Sets whether to reserve the space of this Preference icon view when no icon is provided.
Parameters | |
---|---|
iconSpaceReserved |
boolean : set true if the space for the icon view should be reserved
|
setIntent
void setIntent (Intent intent)
Sets an Intent
to be used for
startActivity(Intent)
when this Preference is clicked.
Parameters | |
---|---|
intent |
Intent : The intent associated with this Preference.
|
setKey
void setKey (String key)
Sets the key for this Preference, which is used as a key to the SharedPreferences
or
PreferenceDataStore
. This should be unique for the package.
Parameters | |
---|---|
key |
String : The key for the preference.
|
setLayoutResource
void setLayoutResource (int layoutResId)
Sets the layout resource that is inflated as the View
to be shown
for this Preference. In most cases, the default layout is sufficient for
custom Preference objects and only the widget layout needs to be changed.
This layout should contain a ViewGroup
with ID
widget_frame
to be the parent of the specific widget
for this Preference. It should similarly contain
title
and summary
.
Parameters | |
---|---|
layoutResId |
int : The layout resource ID to be inflated and returned as
a View . |
See also:
setOnPreferenceChangeListener
void setOnPreferenceChangeListener (Preference.OnPreferenceChangeListener onPreferenceChangeListener)
Sets the callback to be invoked when this Preference is changed by the user (but before the internal state has been updated).
Parameters | |
---|---|
onPreferenceChangeListener |
Preference.OnPreferenceChangeListener : The callback to be invoked.
|
setOnPreferenceClickListener
void setOnPreferenceClickListener (Preference.OnPreferenceClickListener onPreferenceClickListener)
Sets the callback to be invoked when this Preference is clicked.
Parameters | |
---|---|
onPreferenceClickListener |
Preference.OnPreferenceClickListener : The callback to be invoked.
|
setOrder
void setOrder (int order)
Sets the order of this Preference with respect to other Preference objects on the same level.
If this is not specified, the default behavior is to sort alphabetically. The
setOrderingAsAdded(boolean)
can be used to order Preference objects
based on the order they appear in the XML.
Parameters | |
---|---|
order |
int : the order for this Preference. A lower value will be shown first. Use
DEFAULT_ORDER to sort alphabetically or allow ordering from XML |
See also:
setPersistent
void setPersistent (boolean persistent)
Sets whether this Preference is persistent. When persistent, it stores its value(s) into
the persistent SharedPreferences
storage by default or into
PreferenceDataStore
if assigned.
Parameters | |
---|---|
persistent |
boolean : set true if it should store its value(s) into the storage.
|
setPreferenceDataStore
void setPreferenceDataStore (PreferenceDataStore dataStore)
Sets a PreferenceDataStore
to be used by this Preference instead of using
SharedPreferences
.
The data store will remain assigned even if the Preference is moved around the preference
hierarchy. It will also override a data store propagated from the PreferenceManager
that owns this Preference.
Parameters | |
---|---|
dataStore |
PreferenceDataStore : The PreferenceDataStore to be used by this Preference. |
setRecycleEnabled
void setRecycleEnabled (boolean enabled)
Sets whether this Preference has enabled to have its view recycled when used in the list view. By default the recycling is enabled.
The value can be changed only before this preference is added to the preference hierarchy.
If view recycling is not allowed then each time the list view populates this preference
the getView(View, ViewGroup)
method receives a null
convert view and needs
to recreate the view. Otherwise view gets recycled and only onBindView(View)
gets
called.
If you override this method you must call through to the superclass implementation.
Parameters | |
---|---|
enabled |
boolean : set true if this preference view should be recycled
|
setSelectable
void setSelectable (boolean selectable)
Sets whether this Preference is selectable.
Parameters | |
---|---|
selectable |
boolean : set true to make it selectable
|
setShouldDisableView
void setShouldDisableView (boolean shouldDisableView)
Sets whether this Preference should disable its view when it gets disabled.
For example, set this and setEnabled(boolean)
to false for preferences that are
only displaying information and 1) should not be clickable 2) should not have the view set to
the disabled state.
Parameters | |
---|---|
shouldDisableView |
boolean : set true if this preference should disable its view when
the preference is disabled
|
setSingleLineTitle
void setSingleLineTitle (boolean singleLineTitle)
Sets whether to constrain the title of this Preference to a single line instead of letting it wrap onto multiple lines.
Parameters | |
---|---|
singleLineTitle |
boolean : set true if the title should be constrained to one line
|
setSummary
void setSummary (CharSequence summary)
Sets the summary for this Preference with a CharSequence.
Parameters | |
---|---|
summary |
CharSequence : the summary for the preference
|
setSummary
void setSummary (int summaryResId)
Sets the summary for this Preference with a resource ID.
Parameters | |
---|---|
summaryResId |
int : the summary as a resource
|
See also:
setTitle
void setTitle (CharSequence title)
Sets the title for this Preference with a CharSequence. This title will be placed into the ID
title
within the View created by onCreateView(ViewGroup)
.
Parameters | |
---|---|
title |
CharSequence : the title for this Preference
|
setTitle
void setTitle (int titleResId)
Sets the title for this Preference with a resource ID.
Parameters | |
---|---|
titleResId |
int : the title as a resource ID
|
See also:
setWidgetLayoutResource
void setWidgetLayoutResource (int widgetLayoutResId)
Sets the layout for the controllable widget portion of this Preference. This
is inflated into the main layout. For example, a CheckBoxPreference
would specify a custom layout (consisting of just the CheckBox) here,
instead of creating its own main layout.
Parameters | |
---|---|
widgetLayoutResId |
int : The layout resource ID to be inflated into the
main layout. |
See also:
shouldCommit
boolean shouldCommit ()
Returns whether the Preference
should commit its saved value(s) in
getEditor()
. This may return false in situations where batch
committing is being done (by the manager) to improve performance.
If this preference is using PreferenceDataStore
this value is irrelevant.
Returns | |
---|---|
boolean |
Whether the Preference should commit its saved value(s). |
See also:
shouldDisableDependents
boolean shouldDisableDependents ()
Checks whether this preference's dependents should currently be disabled.
Returns | |
---|---|
boolean |
True if the dependents should be disabled, otherwise false. |
toString
String toString ()
Returns a string representation of the object. In general, the
toString
method returns a string that
"textually represents" this object. The result should
be a concise but informative representation that is easy for a
person to read.
It is recommended that all subclasses override this method.
The toString
method for class Object
returns a string consisting of the name of the class of which the
object is an instance, the at-sign character `@
', and
the unsigned hexadecimal representation of the hash code of the
object. In other words, this method returns a string equal to the
value of:
getClass().getName() + '@' + Integer.toHexString(hashCode())
Returns | |
---|---|
String |
a string representation of the object. |
Protected methods
callChangeListener
boolean callChangeListener (Object newValue)
Call this method after the user changes the preference, but before the internal state is set. This allows the client to ignore the user value.
Parameters | |
---|---|
newValue |
Object : The new value of this Preference. |
Returns | |
---|---|
boolean |
True if the user value should be set as the preference value (and persisted). |
findPreferenceInHierarchy
Preference findPreferenceInHierarchy (String key)
Finds a Preference in this hierarchy (the whole thing,
even above/below your PreferenceScreen
screen break) with the given
key.
This only functions after we have been attached to a hierarchy.
Parameters | |
---|---|
key |
String : The key of the Preference to find. |
Returns | |
---|---|
Preference |
The Preference that uses the given key. |
getPersistedBoolean
boolean getPersistedBoolean (boolean defaultReturnValue)
Attempts to get a persisted boolean if this Preference is persistent.
Parameters | |
---|---|
defaultReturnValue |
boolean : The default value to return if either this
Preference is not persistent or this Preference is not present. |
Returns | |
---|---|
boolean |
The value from the data store or the default return value. |
getPersistedFloat
float getPersistedFloat (float defaultReturnValue)
Attempts to get a persisted float if this Preference is persistent.
Parameters | |
---|---|
defaultReturnValue |
float : The default value to return if either this
Preference is not persistent or this Preference is not present. |
Returns | |
---|---|
float |
The value from the data store or the default return value. |
getPersistedInt
int getPersistedInt (int defaultReturnValue)
Attempts to get a persisted int if this Preference is persistent.
Parameters | |
---|---|
defaultReturnValue |
int : The default value to return if either this
Preference is not persistent or this Preference is not present. |
Returns | |
---|---|
int |
The value from the data store or the default return value. |
getPersistedLong
long getPersistedLong (long defaultReturnValue)
Attempts to get a persisted long if this Preference is persistent.
Parameters | |
---|---|
defaultReturnValue |
long : The default value to return if either this
Preference is not persistent or this Preference is not present. |
Returns | |
---|---|
long |
The value from the data store or the default return value. |
getPersistedString
String getPersistedString (String defaultReturnValue)
Attempts to get a persisted String if this Preference is persistent.
Parameters | |
---|---|
defaultReturnValue |
String : The default value to return if either this
Preference is not persistent or this Preference is not present. |
Returns | |
---|---|
String |
The value from the data store or the default return value. |
See also:
notifyChanged
void notifyChanged ()
Should be called when the data of this Preference
has changed.
notifyHierarchyChanged
void notifyHierarchyChanged ()
Should be called when a Preference has been added/removed from this group, or the ordering should be re-evaluated.
onAttachedToActivity
void onAttachedToActivity ()
Called when the Preference hierarchy has been attached to the
PreferenceActivity
. This can also be called when this
Preference has been attached to a group that was already attached
to the PreferenceActivity
.
onAttachedToHierarchy
void onAttachedToHierarchy (PreferenceManager preferenceManager)
Called when this Preference has been attached to a Preference hierarchy. Make sure to call the super implementation.
Parameters | |
---|---|
preferenceManager |
PreferenceManager : The PreferenceManager of the hierarchy.
|
onBindView
void onBindView (View view)
Binds the created View to the data for this Preference.
This is a good place to grab references to custom Views in the layout and set properties on them.
Make sure to call through to the superclass's implementation.
If you override this method you must call through to the superclass implementation.
Parameters | |
---|---|
view |
View : The View that shows this Preference. |
See also:
onClick
void onClick ()
Processes a click on the preference. This includes saving the value to
the SharedPreferences
. However, the overridden method should
call callChangeListener(Object)
to make sure the client wants to
update the preference's state with the new value.
onCreateView
View onCreateView (ViewGroup parent)
Creates the View to be shown for this Preference in the
PreferenceActivity
. The default behavior is to inflate the main
layout of this Preference (see setLayoutResource(int)
. If
changing this behavior, please specify a ViewGroup
with ID
widget_frame
.
Make sure to call through to the superclass's implementation.
If you override this method you must call through to the superclass implementation.
Parameters | |
---|---|
parent |
ViewGroup : The parent that this View will eventually be attached to. |
Returns | |
---|---|
View |
The View that displays this Preference. |
See also:
onGetDefaultValue
Object onGetDefaultValue (TypedArray a, int index)
Called when a Preference is being inflated and the default value attribute needs to be read. Since different Preference types have different value types, the subclass should get and return the default value which will be its value type.
For example, if the value type is String, the body of the method would
proxy to getString(int)
.
Parameters | |
---|---|
a |
TypedArray : The set of attributes. |
index |
int : The index of the default value attribute. |
Returns | |
---|---|
Object |
The default value of this preference type. |
onPrepareForRemoval
void onPrepareForRemoval ()
Called when this Preference is being removed from the hierarchy. You should remove any references to this Preference that you know about. Make sure to call through to the superclass implementation.
If you override this method you must call through to the superclass implementation.
onRestoreInstanceState
void onRestoreInstanceState (Parcelable state)
Hook allowing a Preference to re-apply a representation of its internal state that had
previously been generated by onSaveInstanceState()
. This function will never be called
with a null
state.
Parameters | |
---|---|
state |
Parcelable : The saved state that had previously been returned by
onSaveInstanceState() . |
onSaveInstanceState
Parcelable onSaveInstanceState ()
Hook allowing a Preference to generate a representation of its internal state that can later be used to create a new instance with that same state. This state should only contain information that is not persistent or can be reconstructed later.
Returns | |
---|---|
Parcelable |
A Parcelable object containing the current dynamic state of this Preference, or
null if there is nothing interesting to save. The default implementation
returns null . |
onSetInitialValue
void onSetInitialValue (boolean restorePersistedValue, Object defaultValue)
Implement this to set the initial value of the Preference.
If restorePersistedValue is true, you should restore the
Preference value from the SharedPreferences
. If
restorePersistedValue is false, you should set the Preference
value to defaultValue that is given (and possibly store to SharedPreferences
if shouldPersist()
is true).
In case of using PreferenceDataStore
, the restorePersistedValue is
always true
. But the default value (if provided) is set.
This may not always be called. One example is if it should not persist but there is no default value given.
Parameters | |
---|---|
restorePersistedValue |
boolean : True to restore the persisted value;
false to use the given defaultValue. |
defaultValue |
Object : The default value for this Preference. Only use this
if restorePersistedValue is false.
|
persistBoolean
boolean persistBoolean (boolean value)
Attempts to persist a boolean if this Preference is persistent.
Parameters | |
---|---|
value |
boolean : The value to persist. |
Returns | |
---|---|
boolean |
True if this Preference is persistent. (This is not whether the value was persisted, since we may not necessarily commit if there will be a batch commit later.) |
persistFloat
boolean persistFloat (float value)
Attempts to persist a long if this Preference is persistent.
Parameters | |
---|---|
value |
float : The value to persist. |
Returns | |
---|---|
boolean |
True if this Preference is persistent. (This is not whether the value was persisted, since we may not necessarily commit if there will be a batch commit later.) |
persistInt
boolean persistInt (int value)
Attempts to persist an int if this Preference is persistent.
Parameters | |
---|---|
value |
int : The value to persist. |
Returns | |
---|---|
boolean |
True if this Preference is persistent. (This is not whether the value was persisted, since we may not necessarily commit if there will be a batch commit later.) |
persistLong
boolean persistLong (long value)
Attempts to persist a long if this Preference is persistent.
Parameters | |
---|---|
value |
long : The value to persist. |
Returns | |
---|---|
boolean |
True if this Preference is persistent. (This is not whether the value was persisted, since we may not necessarily commit if there will be a batch commit later.) |
persistString
boolean persistString (String value)
Attempts to persist a String if this Preference is persistent.
Parameters | |
---|---|
value |
String : The value to persist. |
Returns | |
---|---|
boolean |
True if this Preference is persistent. (This is not whether the value was persisted, since we may not necessarily commit if there will be a batch commit later.) |
See also:
shouldPersist
boolean shouldPersist ()
Checks whether, at the given time this method is called, this Preference should store/restore
its value(s) into the SharedPreferences
or into PreferenceDataStore
if
assigned. This, at minimum, checks whether this Preference is persistent and it currently has
a key. Before you save/restore from the storage, check this first.
Returns | |
---|---|
boolean |
True if it should persist the value. |
Interfaces
Classes
- CheckBoxPreference
- DialogPreference
- EditTextPreference
- ListPreference
- MultiSelectListPreference
- Preference
- Preference.BaseSavedState
- PreferenceActivity
- PreferenceActivity.Header
- PreferenceCategory
- PreferenceFragment
- PreferenceGroup
- PreferenceManager
- PreferenceScreen
- RingtonePreference
- SwitchPreference
- TwoStatePreference