Preference
public
class
Preference
extends Object
implements
Comparable<Preference>
java.lang.Object | |
↳ | androidx.preference.Preference |
The basic building block that represents an individual setting displayed to a user in the
preference hierarchy. This class provides the data that will be displayed to the user and has
a reference to the SharedPreferences
or PreferenceDataStore
instance that
persists the preference's values.
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 that represents the key that is used to persist the
value to the device. It is up to the subclass to decide how to store the value.
Developer Guides
For information about building a settings screen using the AndroidX Preference library, see Settings.
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 |
interface |
Preference.SummaryProvider<T extends Preference>
Interface definition for a callback to be invoked when the summary of this
|
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 | |
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boolean
|
callChangeListener(Object newValue)
Call this method after the user changes the preference, but before the internal state is set. |
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. |
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
|
final
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. |
final
SummaryProvider
|
getSummaryProvider()
Returns the |
CharSequence
|
getTitle()
Returns the title of this preference. |
final
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
|
isCopyingEnabled()
Returns whether the summary of this preference can be copied to the clipboard by long pressing on the preference. |
boolean
|
isEnabled()
Checks whether this preference should be enabled in the list. |
boolean
|
isIconSpaceReserved()
Returns whether the space of this preference icon view is reserved. |
boolean
|
isPersistent()
Checks whether this preference is persistent. |
boolean
|
isSelectable()
Checks whether this preference should be selectable in the list. |
final
boolean
|
isShown()
Checks whether this preference is shown to the user in the hierarchy. |
boolean
|
isSingleLineTitle()
Gets whether the title of this preference is constrained to a single line. |
final
boolean
|
isVisible()
Checks whether this preference should be visible to the user. |
void
|
notifyDependencyChange(boolean disableDependents)
Notifies any listening dependents of a change that affects the dependency. |
void
|
onAttached()
Called when the preference hierarchy has been attached to the list of preferences. |
void
|
onBindViewHolder(PreferenceViewHolder holder)
Binds the created View to the data for this preference. |
void
|
onDependencyChanged(Preference dependency, boolean disableDependent)
Called when the dependency changes. |
void
|
onDetached()
Called when the preference hierarchy has been detached from the list of preferences. |
void
|
onInitializeAccessibilityNodeInfo(AccessibilityNodeInfoCompat info)
This method is deprecated.
Preferences aren't views. They should not need any accessibility changes,
unless the view hierarchy is customized. In this situation, please add Accessibility
information in |
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
|
setCopyingEnabled(boolean enabled)
Sets whether the summary of this preference can be copied to the clipboard by long pressing on the preference. |
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
|
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. |
final
void
|
setSummaryProvider(SummaryProvider summaryProvider)
Set a |
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
|
setViewId(int viewId)
Set the ID that will be assigned to the overall View representing this preference, once bound. |
final
void
|
setVisible(boolean visible)
Sets whether this preference should be visible to the user. |
void
|
setWidgetLayoutResource(int widgetLayoutResId)
Sets the layout for the controllable widget portion of this preference. |
boolean
|
shouldDisableDependents()
Checks whether this preference's dependents should currently be disabled. |
String
|
toString()
|
Protected methods | |
---|---|
<T extends Preference>
T
|
findPreferenceInHierarchy(String key)
Finds a preference in the entire hierarchy (above or below this preference) with the given key. |
boolean
|
getPersistedBoolean(boolean defaultReturnValue)
Attempts to get a persisted |
float
|
getPersistedFloat(float defaultReturnValue)
Attempts to get a persisted |
int
|
getPersistedInt(int defaultReturnValue)
Attempts to get a persisted |
long
|
getPersistedLong(long defaultReturnValue)
Attempts to get a persisted |
String
|
getPersistedString(String defaultReturnValue)
Attempts to get a persisted set of Strings 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
|
onAttachedToHierarchy(PreferenceManager preferenceManager)
Called when this preference has been attached to a preference hierarchy. |
void
|
onClick()
Processes a click on the preference. |
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(Object defaultValue)
Implement this to set the initial value of the preference. |
void
|
onSetInitialValue(boolean restorePersistedValue, Object defaultValue)
This method is deprecated.
Use |
boolean
|
persistBoolean(boolean value)
Attempts to persist a |
boolean
|
persistFloat(float value)
Attempts to persist a |
boolean
|
persistInt(int value)
Attempts to persist an |
boolean
|
persistLong(long value)
Attempts to persist a |
boolean
|
persistString(String value)
Attempts to persist a |
boolean
|
shouldPersist()
Checks whether, at the given time this method is called, this preference should store/restore
its value(s) into the |
Inherited methods | |
---|---|
Constants
DEFAULT_ORDER
public static final int DEFAULT_ORDER
Specify for setOrder(int)
if a specific order is not required.
Constant Value: 2147483647 (0x7fffffff)
Public constructors
Preference
public Preference (Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes)
Perform inflation from XML and apply a class-specific base style. This constructor 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. |
Preference
public Preference (Context context, AttributeSet attrs, int defStyleAttr)
Perform inflation from XML and apply a class-specific base style. This constructor 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
public 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
public Preference (Context context)
Constructor to create a preference.
Parameters | |
---|---|
context |
Context : The Context this is associated with, through which it can access the
current theme, resources, SharedPreferences , etc.
|
Public methods
callChangeListener
public 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)
|
compareTo
public 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
public 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 PreferenceFragmentCompat
).
This Context will be used to save the preference values.
Returns | |
---|---|
Context |
The Context of this preference |
getDependency
public String getDependency ()
Returns the key of the dependency on this preference.
Returns | |
---|---|
String |
The key of the dependency |
See also:
getExtras
public 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
public 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
public Drawable getIcon ()
Returns the icon of this preference.
Returns | |
---|---|
Drawable |
The icon |
See also:
getIntent
public Intent getIntent ()
Return the Intent
associated with this preference.
Returns | |
---|---|
Intent |
The Intent last set via setIntent(Intent) or XML
|
getKey
public 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
public final int getLayoutResource ()
Gets the layout resource that will be shown as the View
for this preference.
Returns | |
---|---|
int |
The layout resource ID |
getOnPreferenceChangeListener
public 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
public Preference.OnPreferenceClickListener getOnPreferenceClickListener ()
Returns the callback to be invoked when this preference is clicked.
Returns | |
---|---|
Preference.OnPreferenceClickListener |
The callback to be invoked |
getOrder
public 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
public 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
public 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 storage or the default return value |
See also:
getPreferenceDataStore
public 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
PreferenceManager.setPreferenceDataStore(PreferenceDataStore)
.
Returns | |
---|---|
PreferenceDataStore |
The PreferenceDataStore used by this preference or null if none
|
getPreferenceManager
public PreferenceManager getPreferenceManager ()
Gets the PreferenceManager
that manages this preference object's tree.
Returns | |
---|---|
PreferenceManager |
The PreferenceManager
|
getSharedPreferences
public 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)
.
Returns | |
---|---|
SharedPreferences |
The SharedPreferences where this preference reads its value(s). If this
preference is not attached to a preference hierarchy or if a
PreferenceDataStore has been set, this method returns null . |
getShouldDisableView
public 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
public CharSequence getSummary ()
Returns the summary of this preference. If a Preference.SummaryProvider
has been set for this
preference, it will be used to provide the summary returned by this method.
Returns | |
---|---|
CharSequence |
The summary |
getSummaryProvider
public final SummaryProvider getSummaryProvider ()
Returns the Preference.SummaryProvider
used to configure the summary of this preference.
Returns | |
---|---|
SummaryProvider |
The Preference.SummaryProvider used to configure the summary of this preference, or
null if there is no SummaryProvider set |
See also:
getTitle
public CharSequence getTitle ()
Returns the title of this preference.
Returns | |
---|---|
CharSequence |
The title |
See also:
getWidgetLayoutResource
public final int getWidgetLayoutResource ()
Gets the layout resource for the controllable widget portion of this preference.
Returns | |
---|---|
int |
The layout resource ID |
hasKey
public 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
|
isCopyingEnabled
public boolean isCopyingEnabled ()
Returns whether the summary of this preference can be copied to the clipboard by long pressing on the preference.
Returns | |
---|---|
boolean |
true if copying is enabled, false otherwise
|
isEnabled
public boolean isEnabled ()
Checks whether this preference should be enabled in the list.
Returns | |
---|---|
boolean |
true if this preference is enabled, false otherwise
|
isIconSpaceReserved
public boolean isIconSpaceReserved ()
Returns whether the space of this preference icon view is reserved.
Returns | |
---|---|
boolean |
true if the space of this preference icon view is reserved
R.attr.iconSpaceReserved |
See also:
isPersistent
public 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 persistent
|
isSelectable
public boolean isSelectable ()
Checks whether this preference should be selectable in the list.
Returns | |
---|---|
boolean |
true if it is selectable, false otherwise
|
isShown
public final boolean isShown ()
Checks whether this preference is shown to the user in the hierarchy.
For a preference to be shown in the hierarchy, it and all of its ancestors must be visible
and attached to the root PreferenceScreen
.
Returns | |
---|---|
boolean |
true if this preference is shown to the user in the hierarchy
|
isSingleLineTitle
public 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
R.attr.singleLineTitle |
See also:
isVisible
public final boolean isVisible ()
Checks whether this preference should be visible to the user. If this preference is visible, but one or more of its ancestors are not visible, then this preference will not be shown until its ancestors are all visible.
Returns | |
---|---|
boolean |
true if this preference should be displayed |
See also:
notifyDependencyChange
public 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.
|
onAttached
public void onAttached ()
Called when the preference hierarchy has been attached to the list of preferences. This can also be called when this preference has been attached to a group that was already attached to the list of preferences.
onBindViewHolder
public void onBindViewHolder (PreferenceViewHolder holder)
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.
Parameters | |
---|---|
holder |
PreferenceViewHolder : The ViewHolder that provides references to the views to fill in. These views
will be recycled, so you should not hold a reference to them after this method
returns.
|
onDependencyChanged
public 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
|
onDetached
public void onDetached ()
Called when the preference hierarchy has been detached from the list of preferences. This can also be called when this preference has been removed from a group that was attached to the list of preferences.
onInitializeAccessibilityNodeInfo
public void onInitializeAccessibilityNodeInfo (AccessibilityNodeInfoCompat info)
This method is deprecated.
Preferences aren't views. They should not need any accessibility changes,
unless the view hierarchy is customized. In this situation, please add Accessibility
information in onBindViewHolder(PreferenceViewHolder)
.
Initializes an AccessibilityNodeInfo
with information
about the View for this preference.
Parameters | |
---|---|
info |
AccessibilityNodeInfoCompat |
onParentChanged
public 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
public Bundle peekExtras ()
Return the extras Bundle object associated with this preference, returning null
if
there is not currently one.
Returns | |
---|---|
Bundle |
persistStringSet
public boolean persistStringSet (Set<String> values)
Attempts to persist a set of Strings if this preference is persistent.
The returned value doesn't reflect whether the given value was persisted, since we may not necessarily commit if there will be a batch commit later.
Parameters | |
---|---|
values |
Set : The values to persist |
Returns | |
---|---|
boolean |
true if the preference is persistent, false otherwise |
See also:
restoreHierarchyState
public 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
public 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 |
setCopyingEnabled
public void setCopyingEnabled (boolean enabled)
Sets whether the summary of this preference can be copied to the clipboard by long pressing on the preference.
Parameters | |
---|---|
enabled |
boolean : Set true to enable copying the summary of this preference
|
setDefaultValue
public 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
public 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
public 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
public 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
public void setIcon (Drawable icon)
Sets the icon for this preference with a Drawable. This icon will be placed into the ID
R.id.icon
within the View created by
onBindViewHolder(PreferenceViewHolder)
.
Parameters | |
---|---|
icon |
Drawable : The optional icon for this preference
|
setIcon
public 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
public void setIconSpaceReserved (boolean iconSpaceReserved)
Sets whether to reserve the space of this preference icon view when no icon is provided. If set to true, the preference will be offset as if it would have the icon and thus aligned with other preferences having icons.
Parameters | |
---|---|
iconSpaceReserved |
boolean : Set true if the space for the icon view should be reserved
R.attr.iconSpaceReserved
|
setIntent
public void setIntent (Intent intent)
Sets an Intent
to be used for Context.startActivity(Intent)
when this
preference is clicked.
Parameters | |
---|---|
intent |
Intent : The intent associated with this preference
|
setKey
public 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
public 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
R.id.widget_frame
to be the parent of the specific widget for this
preference. It should similarly contain R.id.title
and
R.id.summary
.
It is an error to change the layout after adding the preference to a
PreferenceGroup
.
Parameters | |
---|---|
layoutResId |
int : The layout resource ID to be inflated and returned as a View |
See also:
setOnPreferenceChangeListener
public 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
public 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
public 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
PreferenceGroup.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. |
setPersistent
public 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
public 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 |
setSelectable
public void setSelectable (boolean selectable)
Sets whether this preference is selectable.
Parameters | |
---|---|
selectable |
boolean : Set true to make it selectable
|
setShouldDisableView
public 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
public 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
R.attr.singleLineTitle
|
setSummary
public void setSummary (CharSequence summary)
Sets the summary for this preference with a CharSequence.
You can also use a Preference.SummaryProvider
to dynamically configure the summary of this
preference.
Parameters | |
---|---|
summary |
CharSequence : The summary for the preference |
Throws | |
---|---|
IllegalStateException |
If a Preference.SummaryProvider has already been set. |
See also:
setSummary
public void setSummary (int summaryResId)
Sets the summary for this preference with a resource ID.
You can also use a Preference.SummaryProvider
to dynamically configure the summary of this
preference.
Parameters | |
---|---|
summaryResId |
int : The summary as a resource |
setSummaryProvider
public final void setSummaryProvider (SummaryProvider summaryProvider)
Set a Preference.SummaryProvider
that will be invoked whenever the summary of this preference
is requested. Set null
to remove the existing SummaryProvider.
Parameters | |
---|---|
summaryProvider |
SummaryProvider : The Preference.SummaryProvider that will be invoked whenever the
summary of this preference is requested |
See also:
setTitle
public void setTitle (CharSequence title)
Sets the title for this preference with a CharSequence. This title will be placed into the
ID R.id.title
within the View bound by
onBindViewHolder(PreferenceViewHolder)
.
Parameters | |
---|---|
title |
CharSequence : The title for this preference
|
setTitle
public 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:
setViewId
public void setViewId (int viewId)
Set the ID that will be assigned to the overall View representing this preference, once bound.
Parameters | |
---|---|
viewId |
int |
See also:
setVisible
public final void setVisible (boolean visible)
Sets whether this preference should be visible to the user. If false, it is excluded from
the adapter, but can still be retrieved using
PreferenceFragmentCompat.findPreference(CharSequence)
.
To show this preference to the user, its ancestors must also all be visible. If you make
a PreferenceGroup
invisible, none of its children will be shown to the user until
the group is visible.
Parameters | |
---|---|
visible |
boolean : Set false if this preference should be hidden from the user
R.attr.isPreferenceVisible |
See also:
setWidgetLayoutResource
public 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.
It is an error to change the layout after adding the preference to a
PreferenceGroup
.
Parameters | |
---|---|
widgetLayoutResId |
int : The layout resource ID to be inflated into the main layout |
See also:
shouldDisableDependents
public boolean shouldDisableDependents ()
Checks whether this preference's dependents should currently be disabled.
Returns | |
---|---|
boolean |
true if the dependents should be disabled, otherwise false
|
toString
public String toString ()
Returns | |
---|---|
String |
Protected methods
findPreferenceInHierarchy
protected T findPreferenceInHierarchy (String key)
Finds a preference in the entire hierarchy (above or below this preference) with the given
key. Returns null
if no preference could be found with the given key.
This only works after this preference has been attached to a hierarchy.
Parameters | |
---|---|
key |
String : The key of the preference to retrieve |
Returns | |
---|---|
T |
The preference with the key, or null |
getPersistedBoolean
protected 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 in the SharedPreferences. |
Returns | |
---|---|
boolean |
The value from the storage or the default return value |
getPersistedFloat
protected 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 saved. |
Returns | |
---|---|
float |
The value from the storage or the default return value |
getPersistedInt
protected int getPersistedInt (int defaultReturnValue)
Attempts to get a persisted Integer
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 in the SharedPreferences. |
Returns | |
---|---|
int |
The value from the storage or the default return value |
getPersistedLong
protected 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 in the SharedPreferences. |
Returns | |
---|---|
long |
The value from the storage or the default return value |
getPersistedString
protected String getPersistedString (String defaultReturnValue)
Attempts to get a persisted set of Strings if this preference is persistent.
Parameters | |
---|---|
defaultReturnValue |
String : The default value to return if either the preference is not
persistent or the preference is not in the shared preferences. |
Returns | |
---|---|
String |
The value from the storage or the default return value |
See also:
notifyChanged
protected void notifyChanged ()
Should be called when the data of this Preference
has changed.
notifyHierarchyChanged
protected void notifyHierarchyChanged ()
Should be called when a preference has been added/removed from this group, or the ordering should be re-evaluated.
onAttachedToHierarchy
protected 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
|
onClick
protected 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.
onGetDefaultValue
protected 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
TypedArray.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
protected 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.
onRestoreInstanceState
protected 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
protected 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
protected void onSetInitialValue (Object defaultValue)
Implement this to set the initial value of the preference.
If you are persisting values to SharedPreferences
or a PreferenceDataStore
you should restore the saved value for the preference.
If you are not persisting values, or there is no value saved for the preference, you should set the value of the preference to defaultValue.
Parameters | |
---|---|
defaultValue |
Object : The default value for the preference if set, otherwise null .
|
onSetInitialValue
protected void onSetInitialValue (boolean restorePersistedValue, Object defaultValue)
This method is deprecated.
Use onSetInitialValue(Object)
instead.
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
protected boolean persistBoolean (boolean value)
Attempts to persist a Boolean
if this preference is persistent.
The returned value doesn't reflect whether the given value was persisted, since we may not necessarily commit if there will be a batch commit later.
Parameters | |
---|---|
value |
boolean : The value to persist |
Returns | |
---|---|
boolean |
true if the preference is persistent, false otherwise |
persistFloat
protected boolean persistFloat (float value)
Attempts to persist a Float
if this preference is persistent.
The returned value doesn't reflect whether the given value was persisted, since we may not necessarily commit if there will be a batch commit later.
Parameters | |
---|---|
value |
float : The value to persist |
Returns | |
---|---|
boolean |
true if the preference is persistent, false otherwise |
persistInt
protected boolean persistInt (int value)
Attempts to persist an Integer
if this preference is persistent.
The returned value doesn't reflect whether the given value was persisted, since we may not necessarily commit if there will be a batch commit later.
Parameters | |
---|---|
value |
int : The value to persist |
Returns | |
---|---|
boolean |
true if the preference is persistent, false otherwise |
persistLong
protected boolean persistLong (long value)
Attempts to persist a Long
if this preference is persistent.
The returned value doesn't reflect whether the given value was persisted, since we may not necessarily commit if there will be a batch commit later.
Parameters | |
---|---|
value |
long : The value to persist |
Returns | |
---|---|
boolean |
true if the preference is persistent, false otherwise |
persistString
protected boolean persistString (String value)
Attempts to persist a String
if this preference is persistent.
The returned value doesn't reflect whether the given value was persisted, since we may not necessarily commit if there will be a batch commit later.
Parameters | |
---|---|
value |
String : The value to persist |
Returns | |
---|---|
boolean |
true if the preference is persistent, false otherwise |
See also:
shouldPersist
protected 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
|
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