/*
* Copyright (C) 2007 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package android.preference;
import java.util.ArrayList;
import java.util.List;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.res.TypedArray;
import android.os.Bundle;
import android.os.Parcel;
import android.os.Parcelable;
import android.text.TextUtils;
import android.util.AttributeSet;
import com.android.internal.util.CharSequences;
import android.view.AbsSavedState;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ListView;
import android.widget.TextView;
/**
* Represents the basic Preference UI building
* block displayed by a {@link PreferenceActivity} in the form of a
* {@link ListView}. This class provides the {@link View} to be displayed in
* the activity and associates with a {@link SharedPreferences} to
* store/retrieve the preference data.
* <p>
* When specifying a preference hierarchy in XML, each element can point to a
* subclass of {@link Preference}, similar to the view hierarchy and layouts.
* <p>
* This class contains a {@code key} that will be used as the key into the
* {@link SharedPreferences}. It is up to the subclass to decide how to store
* the value.
*
* @attr ref android.R.styleable#Preference_key
* @attr ref android.R.styleable#Preference_title
* @attr ref android.R.styleable#Preference_summary
* @attr ref android.R.styleable#Preference_order
* @attr ref android.R.styleable#Preference_layout
* @attr ref android.R.styleable#Preference_widgetLayout
* @attr ref android.R.styleable#Preference_enabled
* @attr ref android.R.styleable#Preference_selectable
* @attr ref android.R.styleable#Preference_dependency
* @attr ref android.R.styleable#Preference_persistent
* @attr ref android.R.styleable#Preference_defaultValue
* @attr ref android.R.styleable#Preference_shouldDisableView
*/
public class Preference implements Comparable<Preference>, OnDependencyChangeListener {
/**
* Specify for {@link #setOrder(int)} if a specific order is not required.
*/
public static final int DEFAULT_ORDER = Integer.MAX_VALUE;
private Context mContext;
private PreferenceManager mPreferenceManager;
/**
* Set when added to hierarchy since we need a unique ID within that
* hierarchy.
*/
private long mId;
private OnPreferenceChangeListener mOnChangeListener;
private OnPreferenceClickListener mOnClickListener;
private int mOrder = DEFAULT_ORDER;
private CharSequence mTitle;
private CharSequence mSummary;
private String mKey;
private Intent mIntent;
private boolean mEnabled = true;
private boolean mSelectable = true;
private boolean mRequiresKey;
private boolean mPersistent = true;
private String mDependencyKey;
private Object mDefaultValue;
/**
* @see #setShouldDisableView(boolean)
*/
private boolean mShouldDisableView = true;
private int mLayoutResId = com.android.internal.R.layout.preference;
private int mWidgetLayoutResId;
private boolean mHasSpecifiedLayout = false;
private OnPreferenceChangeInternalListener mListener;
private List<Preference> mDependents;
private boolean mBaseMethodCalled;
/**
* Interface definition for a callback to be invoked when the value of this
* {@link Preference} has been changed by the user and is
* about to be set and/or persisted. This gives the client a chance
* to prevent setting and/or persisting the value.
*/
public interface OnPreferenceChangeListener {
/**
* Called when a Preference has been changed by the user. This is
* called before the state of the Preference is about to be updated and
* before the state is persisted.
*
* @param preference The changed Preference.
* @param newValue The new value of the Preference.
* @return True to update the state of the Preference with the new value.
*/
boolean onPreferenceChange(Preference preference, Object newValue);
}
/**
* Interface definition for a callback to be invoked when a {@link Preference} is
* clicked.
*/
public interface OnPreferenceClickListener {
/**
* Called when a Preference has been clicked.
*
* @param preference The Preference that was clicked.
* @return True if the click was handled.
*/
boolean onPreferenceClick(Preference preference);
}
/**
* Interface definition for a callback to be invoked when this
* {@link Preference} is changed or, if this is a group, there is an
* addition/removal of {@link Preference}(s). This is used internally.
*/
interface OnPreferenceChangeInternalListener {
/**
* Called when this Preference has changed.
*
* @param preference This preference.
*/
void onPreferenceChange(Preference preference);
/**
* Called when this group has added/removed {@link Preference}(s).
*
* @param preference This Preference.
*/
void onPreferenceHierarchyChange(Preference preference);
}
/**
* 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 {@link CheckBoxPreference}
* constructor calls this version of the super class constructor and
* supplies {@code android.R.attr.checkBoxPreferenceStyle} for <var>defStyle</var>.
* This allows the theme's checkbox preference style to modify all of the base
* preference attributes as well as the {@link CheckBoxPreference} class's
* attributes.
*
* @param context The Context this is associated with, through which it can
* access the current theme, resources, {@link SharedPreferences},
* etc.
* @param attrs The attributes of the XML tag that is inflating the preference.
* @param defStyle The default style to apply to this preference. If 0, no style
* will be applied (beyond what is included in the theme). This
* may either be an attribute resource, whose value will be
* retrieved from the current theme, or an explicit style
* resource.
* @see #Preference(Context, AttributeSet)
*/
public Preference(Context context, AttributeSet attrs, int defStyle) {
mContext = context;
TypedArray a = context.obtainStyledAttributes(attrs,
com.android.internal.R.styleable.Preference);
if (a.hasValue(com.android.internal.R.styleable.Preference_layout) ||
a.hasValue(com.android.internal.R.styleable.Preference_widgetLayout)) {
// This preference has a custom layout defined (not one taken from
// the default style)
mHasSpecifiedLayout = true;
}
a.recycle();
a = context.obtainStyledAttributes(attrs, com.android.internal.R.styleable.Preference,
defStyle, 0);
for (int i = a.getIndexCount(); i >= 0; i--) {
int attr = a.getIndex(i);
switch (attr) {
case com.android.internal.R.styleable.Preference_key:
mKey = a.getString(attr);
break;
case com.android.internal.R.styleable.Preference_title:
mTitle = a.getString(attr);
break;
case com.android.internal.R.styleable.Preference_summary:
mSummary = a.getString(attr);
break;
case com.android.internal.R.styleable.Preference_order:
mOrder = a.getInt(attr, mOrder);
break;
case com.android.internal.R.styleable.Preference_layout:
mLayoutResId = a.getResourceId(attr, mLayoutResId);
break;
case com.android.internal.R.styleable.Preference_widgetLayout:
mWidgetLayoutResId = a.getResourceId(attr, mWidgetLayoutResId);
break;
case com.android.internal.R.styleable.Preference_enabled:
mEnabled = a.getBoolean(attr, true);
break;
case com.android.internal.R.styleable.Preference_selectable:
mSelectable = a.getBoolean(attr, true);
break;
case com.android.internal.R.styleable.Preference_persistent:
mPersistent = a.getBoolean(attr, mPersistent);
break;
case com.android.internal.R.styleable.Preference_dependency:
mDependencyKey = a.getString(attr);
break;
case com.android.internal.R.styleable.Preference_defaultValue:
mDefaultValue = onGetDefaultValue(a, attr);
break;
case com.android.internal.R.styleable.Preference_shouldDisableView:
mShouldDisableView = a.getBoolean(attr, mShouldDisableView);
break;
}
}
a.recycle();
}
/**
* 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.
*
* @param context The Context this is associated with, through which it can
* access the current theme, resources, {@link SharedPreferences},
* etc.
* @param attrs The attributes of the XML tag that is inflating the
* preference.
* @see #Preference(Context, AttributeSet, int)
*/
public Preference(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
/**
* Constructor to create a Preference.
*
* @param context The Context in which to store Preference values.
*/
public Preference(Context context) {
this(context, null);
}
/**
* 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.
* <p>
* For example, if the value type is String, the body of the method would
* proxy to {@link TypedArray#getString(int)}.
*
* @param a The set of attributes.
* @param index The index of the default value attribute.
* @return The default value of this preference type.
*/
protected Object onGetDefaultValue(TypedArray a, int index) {
return null;
}
/**
* Sets an {@link Intent} to be used for
* {@link Context#startActivity(Intent)} when this Preference is clicked.
*
* @param intent The intent associated with this Preference.
*/
public void setIntent(Intent intent) {
mIntent = intent;
}
/**
* Return the {@link Intent} associated with this Preference.
*
* @return The {@link Intent} last set via {@link #setIntent(Intent)} or XML.
*/
public Intent getIntent() {
return mIntent;
}
/**
* Sets the layout resource that is inflated as the {@link 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.
* <p>
* This layout should contain a {@link ViewGroup} with ID
* {@link android.R.id#widget_frame} to be the parent of the specific widget
* for this Preference. It should similarly contain
* {@link android.R.id#title} and {@link android.R.id#summary}.
*
* @param layoutResId The layout resource ID to be inflated and returned as
* a {@link View}.
* @see #setWidgetLayoutResource(int)
*/
public void setLayoutResource(int layoutResId) {
if (!mHasSpecifiedLayout) {
mHasSpecifiedLayout = true;
}
mLayoutResId = layoutResId;
}
/**
* Gets the layout resource that will be shown as the {@link View} for this Preference.
*
* @return The layout resource ID.
*/
public int getLayoutResource() {
return mLayoutResId;
}
/**
* Sets The layout for the controllable widget portion of this Preference. This
* is inflated into the main layout. For example, a {@link CheckBoxPreference}
* would specify a custom layout (consisting of just the CheckBox) here,
* instead of creating its own main layout.
*
* @param widgetLayoutResId The layout resource ID to be inflated into the
* main layout.
* @see #setLayoutResource(int)
*/
public void setWidgetLayoutResource(int widgetLayoutResId) {
mWidgetLayoutResId = widgetLayoutResId;
}
/**
* Gets the layout resource for the controllable widget portion of this Preference.
*
* @return The layout resource ID.
*/
public int getWidgetLayoutResource() {
return mWidgetLayoutResId;
}
/**
* Gets the View that will be shown in the {@link PreferenceActivity}.
*
* @param convertView 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.
* @param parent The parent that this View will eventually be attached to.
* @return Returns the same Preference object, for chaining multiple calls
* into a single statement.
* @see #onCreateView(ViewGroup)
* @see #onBindView(View)
*/
public View getView(View convertView, ViewGroup parent) {
if (convertView == null) {
convertView = onCreateView(parent);
}
onBindView(convertView);
return convertView;
}
/**
* Creates the View to be shown for this Preference in the
* {@link PreferenceActivity}. The default behavior is to inflate the main
* layout of this Preference (see {@link #setLayoutResource(int)}. If
* changing this behavior, please specify a {@link ViewGroup} with ID
* {@link android.R.id#widget_frame}.
* <p>
* Make sure to call through to the superclass's implementation.
*
* @param parent The parent that this View will eventually be attached to.
* @return The View that displays this Preference.
* @see #onBindView(View)
*/
protected View onCreateView(ViewGroup parent) {
final LayoutInflater layoutInflater =
(LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
final View layout = layoutInflater.inflate(mLayoutResId, parent, false);
if (mWidgetLayoutResId != 0) {
final ViewGroup widgetFrame = (ViewGroup)layout.findViewById(com.android.internal.R.id.widget_frame);
layoutInflater.inflate(mWidgetLayoutResId, widgetFrame);
}
return layout;
}
/**
* Binds the created View to the data for this Preference.
* <p>
* This is a good place to grab references to custom Views in the layout and
* set properties on them.
* <p>
* Make sure to call through to the superclass's implementation.
*
* @param view The View that shows this Preference.
* @see #onCreateView(ViewGroup)
*/
protected void onBindView(View view) {
TextView textView = (TextView) view.findViewById(com.android.internal.R.id.title);
if (textView != null) {
textView.setText(getTitle());
}
textView = (TextView) view.findViewById(com.android.internal.R.id.summary);
if (textView != null) {
final CharSequence summary = getSummary();
if (!TextUtils.isEmpty(summary)) {
if (textView.getVisibility() != View.VISIBLE) {
textView.setVisibility(View.VISIBLE);
}
textView.setText(getSummary());
} else {
if (textView.getVisibility() != View.GONE) {
textView.setVisibility(View.GONE);
}
}
}
if (mShouldDisableView) {
setEnabledStateOnViews(view, isEnabled());
}
}
/**
* Makes sure the view (and any children) get the enabled state changed.
*/
private void setEnabledStateOnViews(View v, boolean enabled) {
v.setEnabled(enabled);
if (v instanceof ViewGroup) {
final ViewGroup vg = (ViewGroup) v;
for (int i = vg.getChildCount() - 1; i >= 0; i--) {
setEnabledStateOnViews(vg.getChildAt(i), enabled);
}
}
}
/**
* 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
* {@link PreferenceGroup#setOrderingAsAdded(boolean)} can be used to order
* Preference objects based on the order they appear in the XML.
*
* @param order The order for this Preference. A lower value will be shown
* first. Use {@link #DEFAULT_ORDER} to sort alphabetically or
* allow ordering from XML.
* @see PreferenceGroup#setOrderingAsAdded(boolean)
* @see #DEFAULT_ORDER
*/
public void setOrder(int order) {
if (order != mOrder) {
mOrder = order;
// Reorder the list
notifyHierarchyChanged();
}
}
/**
* Gets the order of this Preference with respect to other Preference objects
* on the same level.
*
* @return The order of this Preference.
* @see #setOrder(int)
*/
public int getOrder() {
return mOrder;
}
/**
* Sets the title for this Preference with a CharSequence.
* This title will be placed into the ID
* {@link android.R.id#title} within the View created by
* {@link #onCreateView(ViewGroup)}.
*
* @param title The title for this Preference.
*/
public void setTitle(CharSequence title) {
if (title == null && mTitle != null || title != null && !title.equals(mTitle)) {
mTitle = title;
notifyChanged();
}
}
/**
* Sets the title for this Preference with a resource ID.
*
* @see #setTitle(CharSequence)
* @param titleResId The title as a resource ID.
*/
public void setTitle(int titleResId) {
setTitle(mContext.getString(titleResId));
}
/**
* Returns the title of this Preference.
*
* @return The title.
* @see #setTitle(CharSequence)
*/
public CharSequence getTitle() {
return mTitle;
}
/**
* Returns the summary of this Preference.
*
* @return The summary.
* @see #setSummary(CharSequence)
*/
public CharSequence getSummary() {
return mSummary;
}
/**
* Sets the summary for this Preference with a CharSequence.
*
* @param summary The summary for the preference.
*/
public void setSummary(CharSequence summary) {
if (summary == null && mSummary != null || summary != null && !summary.equals(mSummary)) {
mSummary = summary;
notifyChanged();
}
}
/**
* Sets the summary for this Preference with a resource ID.
*
* @see #setSummary(CharSequence)
* @param summaryResId The summary as a resource.
*/
public void setSummary(int summaryResId) {
setSummary(mContext.getString(summaryResId));
}
/**
* Sets whether this Preference is enabled. If disabled, it will
* not handle clicks.
*
* @param enabled Set true to enable it.
*/
public void setEnabled(boolean enabled) {
if (mEnabled != enabled) {
mEnabled = enabled;
// Enabled state can change dependent preferences' states, so notify
notifyDependencyChange(shouldDisableDependents());
notifyChanged();
}
}
/**
* Checks whether this Preference should be enabled in the list.
*
* @return True if this Preference is enabled, false otherwise.
*/
public boolean isEnabled() {
return mEnabled;
}
/**
* Sets whether this Preference is selectable.
*
* @param selectable Set true to make it selectable.
*/
public void setSelectable(boolean selectable) {
if (mSelectable != selectable) {
mSelectable = selectable;
notifyChanged();
}
}
/**
* Checks whether this Preference should be selectable in the list.
*
* @return True if it is selectable, false otherwise.
*/
public boolean isSelectable() {
return mSelectable;
}
/**
* Sets whether this Preference should disable its view when it gets
* disabled.
* <p>
* For example, set this and {@link #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.
*
* @param shouldDisableView Set true if this preference should disable its view
* when the preference is disabled.
*/
public void setShouldDisableView(boolean shouldDisableView) {
mShouldDisableView = shouldDisableView;
notifyChanged();
}
/**
* Checks whether this Preference should disable its view when it's action is disabled.
* @see #setShouldDisableView(boolean)
* @return True if it should disable the view.
*/
public boolean getShouldDisableView() {
return mShouldDisableView;
}
/**
* Returns a unique ID for this Preference. This ID should be unique across all
* Preference objects in a hierarchy.
*
* @return A unique ID for this Preference.
*/
long getId() {
return mId;
}
/**
* Processes a click on the preference. This includes saving the value to
* the {@link SharedPreferences}. However, the overridden method should
* call {@link #callChangeListener(Object)} to make sure the client wants to
* update the preference's state with the new value.
*/
protected void onClick() {
}
/**
* Sets the key for this Preference, which is used as a key to the
* {@link SharedPreferences}. This should be unique for the package.
*
* @param key The key for the preference.
*/
public void setKey(String key) {
mKey = key;
if (mRequiresKey && !hasKey()) {
requireKey();
}
}
/**
* Gets the key for this Preference, which is also the key used for storing
* values into SharedPreferences.
*
* @return The key.
*/
public String getKey() {
return mKey;
}
/**
* Checks whether the key is present, and if it isn't throws an
* exception. This should be called by subclasses that store preferences in
* the {@link SharedPreferences}.
*
* @throws IllegalStateException If there is no key assigned.
*/
void requireKey() {
if (mKey == null) {
throw new IllegalStateException("Preference does not have a key assigned.");
}
mRequiresKey = true;
}
/**
* Checks whether this Preference has a valid key.
*
* @return True if the key exists and is not a blank string, false otherwise.
*/
public boolean hasKey() {
return !TextUtils.isEmpty(mKey);
}
/**
* Checks whether this Preference is persistent. If it is, it stores its value(s) into
* the persistent {@link SharedPreferences} storage.
*
* @return True if it is persistent.
*/
public boolean isPersistent() {
return mPersistent;
}
/**
* Checks whether, at the given time this method is called,
* this Preference should store/restore its value(s) into the
* {@link SharedPreferences}. This, at minimum, checks whether this
* Preference is persistent and it currently has a key. Before you
* save/restore from the {@link SharedPreferences}, check this first.
*
* @return True if it should persist the value.
*/
protected boolean shouldPersist() {
return mPreferenceManager != null && isPersistent() && hasKey();
}
/**
* Sets whether this Preference is persistent. When persistent,
* it stores its value(s) into the persistent {@link SharedPreferences}
* storage.
*
* @param persistent Set true if it should store its value(s) into the {@link SharedPreferences}.
*/
public void setPersistent(boolean persistent) {
mPersistent = persistent;
}
/**
* 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.
*
* @param newValue The new value of this Preference.
* @return True if the user value should be set as the preference
* value (and persisted).
*/
protected boolean callChangeListener(Object newValue) {
return mOnChangeListener == null ? true : mOnChangeListener.onPreferenceChange(this, newValue);
}
/**
* Sets the callback to be invoked when this Preference is changed by the
* user (but before the internal state has been updated).
*
* @param onPreferenceChangeListener The callback to be invoked.
*/
public void setOnPreferenceChangeListener(OnPreferenceChangeListener onPreferenceChangeListener) {
mOnChangeListener = onPreferenceChangeListener;
}
/**
* Returns the callback to be invoked when this Preference is changed by the
* user (but before the internal state has been updated).
*
* @return The callback to be invoked.
*/
public OnPreferenceChangeListener getOnPreferenceChangeListener() {
return mOnChangeListener;
}
/**
* Sets the callback to be invoked when this Preference is clicked.
*
* @param onPreferenceClickListener The callback to be invoked.
*/
public void setOnPreferenceClickListener(OnPreferenceClickListener onPreferenceClickListener) {
mOnClickListener = onPreferenceClickListener;
}
/**
* Returns the callback to be invoked when this Preference is clicked.
*
* @return The callback to be invoked.
*/
public OnPreferenceClickListener getOnPreferenceClickListener() {
return mOnClickListener;
}
/**
* Called when a click should be performed.
*
* @param preferenceScreen A {@link PreferenceScreen} whose hierarchy click
* listener should be called in the proper order (between other
* processing). May be null.
*/
void performClick(PreferenceScreen preferenceScreen) {
if (!isEnabled()) {
return;
}
onClick();
if (mOnClickListener != null && mOnClickListener.onPreferenceClick(this)) {
return;
}
PreferenceManager preferenceManager = getPreferenceManager();
if (preferenceManager != null) {
PreferenceManager.OnPreferenceTreeClickListener listener = preferenceManager
.getOnPreferenceTreeClickListener();
if (preferenceScreen != null && listener != null
&& listener.onPreferenceTreeClick(preferenceScreen, this)) {
return;
}
}
if (mIntent != null) {
Context context = getContext();
context.startActivity(mIntent);
}
}
/**
* Returns the {@link android.content.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
* {@link PreferenceActivity}). This Context will be used to save the Preference values.
*
* @return The Context of this Preference.
*/
public Context getContext() {
return mContext;
}
/**
* Returns the {@link SharedPreferences} where this Preference can read its
* value(s). Usually, it's easier to use one of the helper read methods:
* {@link #getPersistedBoolean(boolean)}, {@link #getPersistedFloat(float)},
* {@link #getPersistedInt(int)}, {@link #getPersistedLong(long)},
* {@link #getPersistedString(String)}. To save values, see
* {@link #getEditor()}.
* <p>
* In some cases, writes to the {@link #getEditor()} will not be committed
* right away and hence not show up in the returned
* {@link SharedPreferences}, this is intended behavior to improve
* performance.
*
* @return The {@link SharedPreferences} where this Preference reads its
* value(s), or null if it isn't attached to a Preference hierarchy.
* @see #getEditor()
*/
public SharedPreferences getSharedPreferences() {
if (mPreferenceManager == null) {
return null;
}
return mPreferenceManager.getSharedPreferences();
}
/**
* Returns an {@link SharedPreferences.Editor} where this Preference can
* save its value(s). Usually it's easier to use one of the helper save
* methods: {@link #persistBoolean(boolean)}, {@link #persistFloat(float)},
* {@link #persistInt(int)}, {@link #persistLong(long)},
* {@link #persistString(String)}. To read values, see
* {@link #getSharedPreferences()}. If {@link #shouldCommit()} returns
* true, it is this Preference's responsibility to commit.
* <p>
* 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.
*
* @return A {@link SharedPreferences.Editor} where this preference saves
* its value(s), or null if it isn't attached to a Preference
* hierarchy.
* @see #shouldCommit()
* @see #getSharedPreferences()
*/
public SharedPreferences.Editor getEditor() {
if (mPreferenceManager == null) {
return null;
}
return mPreferenceManager.getEditor();
}
/**
* Returns whether the {@link Preference} should commit its saved value(s) in
* {@link #getEditor()}. This may return false in situations where batch
* committing is being done (by the manager) to improve performance.
*
* @return Whether the Preference should commit its saved value(s).
* @see #getEditor()
*/
public boolean shouldCommit() {
if (mPreferenceManager == null) {
return false;
}
return mPreferenceManager.shouldCommit();
}
/**
* Compares Preference objects based on order (if set), otherwise alphabetically on the titles.
*
* @param another The Preference to compare to this one.
* @return 0 if the same; less than 0 if this Preference sorts ahead of <var>another</var>;
* greater than 0 if this Preference sorts after <var>another</var>.
*/
public int compareTo(Preference another) {
if (mOrder != DEFAULT_ORDER
|| (mOrder == DEFAULT_ORDER && another.mOrder != DEFAULT_ORDER)) {
// Do order comparison
return mOrder - another.mOrder;
} else if (mTitle == null) {
return 1;
} else if (another.mTitle == null) {
return -1;
} else {
// Do name comparison
return CharSequences.compareToIgnoreCase(mTitle, another.mTitle);
}
}
/**
* Sets the internal change listener.
*
* @param listener The listener.
* @see #notifyChanged()
*/
final void setOnPreferenceChangeInternalListener(OnPreferenceChangeInternalListener listener) {
mListener = listener;
}
/**
* Should be called when the data of this {@link Preference} has changed.
*/
protected void notifyChanged() {
if (mListener != null) {
mListener.onPreferenceChange(this);
}
}
/**
* Should be called when a Preference has been
* added/removed from this group, or the ordering should be
* re-evaluated.
*/
protected void notifyHierarchyChanged() {
if (mListener != null) {
mListener.onPreferenceHierarchyChange(this);
}
}
/**
* Gets the {@link PreferenceManager} that manages this Preference object's tree.
*
* @return The {@link PreferenceManager}.
*/
public PreferenceManager getPreferenceManager() {
return mPreferenceManager;
}
/**
* Called when this Preference has been attached to a Preference hierarchy.
* Make sure to call the super implementation.
*
* @param preferenceManager The PreferenceManager of the hierarchy.
*/
protected void onAttachedToHierarchy(PreferenceManager preferenceManager) {
mPreferenceManager = preferenceManager;
mId = preferenceManager.getNextId();
dispatchSetInitialValue();
}
/**
* Called when the Preference hierarchy has been attached to the
* {@link PreferenceActivity}. This can also be called when this
* Preference has been attached to a group that was already attached
* to the {@link PreferenceActivity}.
*/
protected void onAttachedToActivity() {
// At this point, the hierarchy that this preference is in is connected
// with all other preferences.
registerDependency();
}
private void registerDependency() {
if (TextUtils.isEmpty(mDependencyKey)) return;
Preference preference = findPreferenceInHierarchy(mDependencyKey);
if (preference != null) {
preference.registerDependent(this);
} else {
throw new IllegalStateException("Dependency \"" + mDependencyKey
+ "\" not found for preference \"" + mKey + "\" (title: \"" + mTitle + "\"");
}
}
private void unregisterDependency() {
if (mDependencyKey != null) {
final Preference oldDependency = findPreferenceInHierarchy(mDependencyKey);
if (oldDependency != null) {
oldDependency.unregisterDependent(this);
}
}
}
/**
* Finds a Preference in this hierarchy (the whole thing,
* even above/below your {@link PreferenceScreen} screen break) with the given
* key.
* <p>
* This only functions after we have been attached to a hierarchy.
*
* @param key The key of the Preference to find.
* @return The Preference that uses the given key.
*/
protected Preference findPreferenceInHierarchy(String key) {
if (TextUtils.isEmpty(key) || mPreferenceManager == null) {
return null;
}
return mPreferenceManager.findPreference(key);
}
/**
* Adds a dependent Preference on this Preference so we can notify it.
* Usually, the dependent Preference registers itself (it's good for it to
* know it depends on something), so please use
* {@link Preference#setDependency(String)} on the dependent Preference.
*
* @param dependent The dependent Preference that will be enabled/disabled
* according to the state of this Preference.
*/
private void registerDependent(Preference dependent) {
if (mDependents == null) {
mDependents = new ArrayList<Preference>();
}
mDependents.add(dependent);
dependent.onDependencyChanged(this, shouldDisableDependents());
}
/**
* Removes a dependent Preference on this Preference.
*
* @param dependent The dependent Preference that will be enabled/disabled
* according to the state of this Preference.
* @return Returns the same Preference object, for chaining multiple calls
* into a single statement.
*/
private void unregisterDependent(Preference dependent) {
if (mDependents != null) {
mDependents.remove(dependent);
}
}
/**
* Notifies any listening dependents of a change that affects the
* dependency.
*
* @param disableDependents Whether this Preference should disable
* its dependents.
*/
public void notifyDependencyChange(boolean disableDependents) {
final List<Preference> dependents = mDependents;
if (dependents == null) {
return;
}
final int dependentsCount = dependents.size();
for (int i = 0; i < dependentsCount; i++) {
dependents.get(i).onDependencyChanged(this, disableDependents);
}
}
/**
* Called when the dependency changes.
*
* @param dependency The Preference that this Preference depends on.
* @param disableDependent Set true to disable this Preference.
*/
public void onDependencyChanged(Preference dependency, boolean disableDependent) {
setEnabled(!disableDependent);
}
/**
* Checks whether this preference's dependents should currently be
* disabled.
*
* @return True if the dependents should be disabled, otherwise false.
*/
public boolean shouldDisableDependents() {
return !isEnabled();
}
/**
* 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.
*
* @param dependencyKey The key of the Preference that this depends on.
*/
public void setDependency(String dependencyKey) {
// Unregister the old dependency, if we had one
unregisterDependency();
// Register the new
mDependencyKey = dependencyKey;
registerDependency();
}
/**
* Returns the key of the dependency on this Preference.
*
* @return The key of the dependency.
* @see #setDependency(String)
*/
public String getDependency() {
return mDependencyKey;
}
/**
* 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.
*/
protected void onPrepareForRemoval() {
unregisterDependency();
}
/**
* 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.
*
* @param defaultValue The default value.
*/
public void setDefaultValue(Object defaultValue) {
mDefaultValue = defaultValue;
}
private void dispatchSetInitialValue() {
// By now, we know if we are persistent.
final boolean shouldPersist = shouldPersist();
if (!shouldPersist || !getSharedPreferences().contains(mKey)) {
if (mDefaultValue != null) {
onSetInitialValue(false, mDefaultValue);
}
} else {
onSetInitialValue(true, null);
}
}
/**
* Implement this to set the initial value of the Preference.
* <p>
* If <var>restorePersistedValue</var> is true, you should restore the
* Preference value from the {@link android.content.SharedPreferences}. If
* <var>restorePersistedValue</var> is false, you should set the Preference
* value to defaultValue that is given (and possibly store to SharedPreferences
* if {@link #shouldPersist()} is true).
* <p>
* This may not always be called. One example is if it should not persist
* but there is no default value given.
*
* @param restorePersistedValue True to restore the persisted value;
* false to use the given <var>defaultValue</var>.
* @param defaultValue The default value for this Preference. Only use this
* if <var>restorePersistedValue</var> is false.
*/
protected void onSetInitialValue(boolean restorePersistedValue, Object defaultValue) {
}
private void tryCommit(SharedPreferences.Editor editor) {
if (mPreferenceManager.shouldCommit()) {
editor.commit();
}
}
/**
* Attempts to persist a String to the {@link android.content.SharedPreferences}.
* <p>
* This will check if this Preference is persistent, get an editor from
* the {@link PreferenceManager}, put in the string, and check if we should commit (and
* commit if so).
*
* @param value The value to persist.
* @return True if the 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 #getPersistedString(String)
*/
protected boolean persistString(String value) {
if (shouldPersist()) {
// Shouldn't store null
if (value == getPersistedString(null)) {
// It's already there, so the same as persisting
return true;
}
SharedPreferences.Editor editor = mPreferenceManager.getEditor();
editor.putString(mKey, value);
tryCommit(editor);
return true;
}
return false;
}
/**
* Attempts to get a persisted String from the {@link android.content.SharedPreferences}.
* <p>
* This will check if this Preference is persistent, get the SharedPreferences
* from the {@link PreferenceManager}, and get the value.
*
* @param defaultReturnValue The default value to return if either the
* Preference is not persistent or the Preference is not in the
* shared preferences.
* @return The value from the SharedPreferences or the default return
* value.
* @see #persistString(String)
*/
protected String getPersistedString(String defaultReturnValue) {
if (!shouldPersist()) {
return defaultReturnValue;
}
return mPreferenceManager.getSharedPreferences().getString(mKey, defaultReturnValue);
}
/**
* Attempts to persist an int to the {@link android.content.SharedPreferences}.
*
* @param value The value to persist.
* @return True if the 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 #persistString(String)
* @see #getPersistedInt(int)
*/
protected boolean persistInt(int value) {
if (shouldPersist()) {
if (value == getPersistedInt(~value)) {
// It's already there, so the same as persisting
return true;
}
SharedPreferences.Editor editor = mPreferenceManager.getEditor();
editor.putInt(mKey, value);
tryCommit(editor);
return true;
}
return false;
}
/**
* Attempts to get a persisted int from the {@link android.content.SharedPreferences}.
*
* @param defaultReturnValue The default value to return if either this
* Preference is not persistent or this Preference is not in the
* SharedPreferences.
* @return The value from the SharedPreferences or the default return
* value.
* @see #getPersistedString(String)
* @see #persistInt(int)
*/
protected int getPersistedInt(int defaultReturnValue) {
if (!shouldPersist()) {
return defaultReturnValue;
}
return mPreferenceManager.getSharedPreferences().getInt(mKey, defaultReturnValue);
}
/**
* Attempts to persist a float to the {@link android.content.SharedPreferences}.
*
* @param value The value to persist.
* @return 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 #persistString(String)
* @see #getPersistedFloat(float)
*/
protected boolean persistFloat(float value) {
if (shouldPersist()) {
if (value == getPersistedFloat(Float.NaN)) {
// It's already there, so the same as persisting
return true;
}
SharedPreferences.Editor editor = mPreferenceManager.getEditor();
editor.putFloat(mKey, value);
tryCommit(editor);
return true;
}
return false;
}
/**
* Attempts to get a persisted float from the {@link android.content.SharedPreferences}.
*
* @param defaultReturnValue The default value to return if either this
* Preference is not persistent or this Preference is not in the
* SharedPreferences.
* @return The value from the SharedPreferences or the default return
* value.
* @see #getPersistedString(String)
* @see #persistFloat(float)
*/
protected float getPersistedFloat(float defaultReturnValue) {
if (!shouldPersist()) {
return defaultReturnValue;
}
return mPreferenceManager.getSharedPreferences().getFloat(mKey, defaultReturnValue);
}
/**
* Attempts to persist a long to the {@link android.content.SharedPreferences}.
*
* @param value The value to persist.
* @return 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 #persistString(String)
* @see #getPersistedLong(long)
*/
protected boolean persistLong(long value) {
if (shouldPersist()) {
if (value == getPersistedLong(~value)) {
// It's already there, so the same as persisting
return true;
}
SharedPreferences.Editor editor = mPreferenceManager.getEditor();
editor.putLong(mKey, value);
tryCommit(editor);
return true;
}
return false;
}
/**
* Attempts to get a persisted long from the {@link android.content.SharedPreferences}.
*
* @param defaultReturnValue The default value to return if either this
* Preference is not persistent or this Preference is not in the
* SharedPreferences.
* @return The value from the SharedPreferences or the default return
* value.
* @see #getPersistedString(String)
* @see #persistLong(long)
*/
protected long getPersistedLong(long defaultReturnValue) {
if (!shouldPersist()) {
return defaultReturnValue;
}
return mPreferenceManager.getSharedPreferences().getLong(mKey, defaultReturnValue);
}
/**
* Attempts to persist a boolean to the {@link android.content.SharedPreferences}.
*
* @param value The value to persist.
* @return 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 #persistString(String)
* @see #getPersistedBoolean(boolean)
*/
protected boolean persistBoolean(boolean value) {
if (shouldPersist()) {
if (value == getPersistedBoolean(!value)) {
// It's already there, so the same as persisting
return true;
}
SharedPreferences.Editor editor = mPreferenceManager.getEditor();
editor.putBoolean(mKey, value);
tryCommit(editor);
return true;
}
return false;
}
/**
* Attempts to get a persisted boolean from the {@link android.content.SharedPreferences}.
*
* @param defaultReturnValue The default value to return if either this
* Preference is not persistent or this Preference is not in the
* SharedPreferences.
* @return The value from the SharedPreferences or the default return
* value.
* @see #getPersistedString(String)
* @see #persistBoolean(boolean)
*/
protected boolean getPersistedBoolean(boolean defaultReturnValue) {
if (!shouldPersist()) {
return defaultReturnValue;
}
return mPreferenceManager.getSharedPreferences().getBoolean(mKey, defaultReturnValue);
}
boolean hasSpecifiedLayout() {
return mHasSpecifiedLayout;
}
@Override
public String toString() {
return getFilterableStringBuilder().toString();
}
/**
* Returns the text that will be used to filter this Preference depending on
* user input.
* <p>
* If overridding and calling through to the superclass, make sure to prepend
* your additions with a space.
*
* @return Text as a {@link StringBuilder} that will be used to filter this
* preference. By default, this is the title and summary
* (concatenated with a space).
*/
StringBuilder getFilterableStringBuilder() {
StringBuilder sb = new StringBuilder();
CharSequence title = getTitle();
if (!TextUtils.isEmpty(title)) {
sb.append(title).append(' ');
}
CharSequence summary = getSummary();
if (!TextUtils.isEmpty(summary)) {
sb.append(summary).append(' ');
}
// Drop the last space
sb.setLength(sb.length() - 1);
return sb;
}
/**
* Store this Preference hierarchy's frozen state into the given container.
*
* @param container The Bundle in which to save the instance of this Preference.
*
* @see #restoreHierarchyState
* @see #onSaveInstanceState
*/
public void saveHierarchyState(Bundle container) {
dispatchSaveInstanceState(container);
}
/**
* Called by {@link #saveHierarchyState} to store the instance for this Preference and its children.
* May be overridden to modify how the save happens for children. For example, some
* Preference objects may want to not store an instance for their children.
*
* @param container The Bundle in which to save the instance of this Preference.
*
* @see #saveHierarchyState
* @see #onSaveInstanceState
*/
void dispatchSaveInstanceState(Bundle container) {
if (hasKey()) {
mBaseMethodCalled = false;
Parcelable state = onSaveInstanceState();
if (!mBaseMethodCalled) {
throw new IllegalStateException(
"Derived class did not call super.onSaveInstanceState()");
}
if (state != null) {
container.putParcelable(mKey, state);
}
}
}
/**
* 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.
*
* @return 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.
* @see #onRestoreInstanceState
* @see #saveHierarchyState
*/
protected Parcelable onSaveInstanceState() {
mBaseMethodCalled = true;
return BaseSavedState.EMPTY_STATE;
}
/**
* Restore this Preference hierarchy's previously saved state from the given container.
*
* @param container The Bundle that holds the previously saved state.
*
* @see #saveHierarchyState
* @see #onRestoreInstanceState
*/
public void restoreHierarchyState(Bundle container) {
dispatchRestoreInstanceState(container);
}
/**
* Called by {@link #restoreHierarchyState} to retrieve the saved state for this
* Preference and its children. May be overridden to modify how restoring
* happens to the children of a Preference. For example, some Preference objects may
* not want to save state for their children.
*
* @param container The Bundle that holds the previously saved state.
* @see #restoreHierarchyState
* @see #onRestoreInstanceState
*/
void dispatchRestoreInstanceState(Bundle container) {
if (hasKey()) {
Parcelable state = container.getParcelable(mKey);
if (state != null) {
mBaseMethodCalled = false;
onRestoreInstanceState(state);
if (!mBaseMethodCalled) {
throw new IllegalStateException(
"Derived class did not call super.onRestoreInstanceState()");
}
}
}
}
/**
* Hook allowing a Preference to re-apply a representation of its internal
* state that had previously been generated by {@link #onSaveInstanceState}.
* This function will never be called with a null state.
*
* @param state The saved state that had previously been returned by
* {@link #onSaveInstanceState}.
* @see #onSaveInstanceState
* @see #restoreHierarchyState
*/
protected void onRestoreInstanceState(Parcelable state) {
mBaseMethodCalled = true;
if (state != BaseSavedState.EMPTY_STATE && state != null) {
throw new IllegalArgumentException("Wrong state class -- expecting Preference State");
}
}
/**
* A base class for managing the instance state of a {@link Preference}.
*/
public static class BaseSavedState extends AbsSavedState {
public BaseSavedState(Parcel source) {
super(source);
}
public BaseSavedState(Parcelable superState) {
super(superState);
}
public static final Parcelable.Creator<BaseSavedState> CREATOR =
new Parcelable.Creator<BaseSavedState>() {
public BaseSavedState createFromParcel(Parcel in) {
return new BaseSavedState(in);
}
public BaseSavedState[] newArray(int size) {
return new BaseSavedState[size];
}
};
}
}
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