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/* * Copyright (C) 2015 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 rikka.materialpreference; import android.content.Context; import android.content.Intent; import android.content.SharedPreferences; import android.content.res.TypedArray; import android.graphics.drawable.Drawable; import android.os.Bundle; import android.os.Parcel; import android.os.Parcelable; import android.support.annotation.NonNull; import android.support.v4.content.ContextCompat; import android.support.v4.content.SharedPreferencesCompat; import android.support.v4.content.res.TypedArrayUtils; import android.text.TextUtils; import android.util.AttributeSet; import android.view.AbsSavedState; import android.view.View; import android.view.ViewGroup; import android.widget.ImageView; import android.widget.TextView; import java.util.ArrayList; import java.util.List; /** * Represents the basic Preference UI building * block displayed by a {@link PreferenceFragment} in the form of a * {@link android.support.v7.widget.RecyclerView}. This class provides data for the * {@link android.view.View} to be displayed * in the list 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. * * <div class="special reference"> * <h3>Developer Guides</h3> * <p>For information about building a settings UI with Preferences, * read the <a href="{@docRoot}guide/topics/ui/settings.html">Settings</a> * guide.</p> * </div> * * @attr ref android.R.styleable#Preference_icon * @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_fragment * @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> { /** * 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; /** * mIconResId is overridden by mIcon, if mIcon is specified. */ private int mIconResId; private Drawable mIcon; private String mKey; private Intent mIntent; private String mFragment; private Bundle mExtras; private boolean mEnabled = true; private boolean mSelectable = true; private boolean mRequiresKey; private boolean mPersistent = true; private String mDependencyKey; private Object mDefaultValue; private boolean mDependencyMet = true; private boolean mParentDependencyMet = true; private boolean mVisible = true; /** * @see #setShouldDisableView(boolean) */ private boolean mShouldDisableView = true; private int mLayoutResId = R.layout.preference_material; private int mWidgetLayoutResId; private OnPreferenceChangeInternalListener mListener; private List<Preference> mDependents; private boolean mBaseMethodCalled; private final View.OnClickListener mClickListener = new View.OnClickListener() { @Override public void onClick(View v) { performClick(v); } }; /** * 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); /** * Called when this preference has changed its visibility. * * @param preference This Preference. */ void onPreferenceVisibilityChange(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>defStyleAttr</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 android.content.SharedPreferences}, etc. * @param attrs The attributes of the XML tag that is inflating the * preference. * @param defStyleAttr 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. * @param defStyleRes A resource identifier of a style resource that * supplies default values for the view, used only if * defStyleAttr is 0 or can not be found in the theme. Can be 0 * to not look for defaults. * @see #Preference(Context, android.util.AttributeSet) */ public Preference(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) { mContext = context; final TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.Preference, defStyleAttr, defStyleRes); mIconResId = TypedArrayUtils.getResourceId(a, R.styleable.Preference_icon, R.styleable.Preference_android_icon, 0); mKey = TypedArrayUtils.getString(a, R.styleable.Preference_key, R.styleable.Preference_android_key); mTitle = TypedArrayUtils.getString(a, R.styleable.Preference_title, R.styleable.Preference_android_title); mSummary = TypedArrayUtils.getString(a, R.styleable.Preference_summary, R.styleable.Preference_android_summary); mOrder = TypedArrayUtils.getInt(a, R.styleable.Preference_order, R.styleable.Preference_android_order, DEFAULT_ORDER); mFragment = TypedArrayUtils.getString(a, R.styleable.Preference_fragment, R.styleable.Preference_android_fragment); mLayoutResId = TypedArrayUtils.getResourceId(a, R.styleable.Preference_layout, R.styleable.Preference_android_layout, R.layout.preference_material); mWidgetLayoutResId = TypedArrayUtils.getResourceId(a, R.styleable.Preference_widgetLayout, R.styleable.Preference_android_widgetLayout, 0); mEnabled = TypedArrayUtils.getBoolean(a, R.styleable.Preference_enabled, R.styleable.Preference_android_enabled, true); mSelectable = TypedArrayUtils.getBoolean(a, R.styleable.Preference_selectable, R.styleable.Preference_android_selectable, true); mPersistent = TypedArrayUtils.getBoolean(a, R.styleable.Preference_persistent, R.styleable.Preference_android_persistent, true); mDependencyKey = TypedArrayUtils.getString(a, R.styleable.Preference_dependency, R.styleable.Preference_android_dependency); if (a.hasValue(R.styleable.Preference_defaultValue)) { mDefaultValue = onGetDefaultValue(a, R.styleable.Preference_defaultValue); } else if (a.hasValue(R.styleable.Preference_android_defaultValue)) { mDefaultValue = onGetDefaultValue(a, R.styleable.Preference_android_defaultValue); } mShouldDisableView = TypedArrayUtils.getBoolean(a, R.styleable.Preference_shouldDisableView, R.styleable.Preference_shouldDisableView, true); a.recycle(); } /** * 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>defStyleAttr</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 android.content.SharedPreferences}, etc. * @param attrs The attributes of the XML tag that is inflating the * preference. * @param defStyleAttr 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 #Preference(Context, AttributeSet) */ public Preference(Context context, AttributeSet attrs, int defStyleAttr) { this(context, attrs, defStyleAttr, 0); } /** * 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 android.content.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, R.attr.preferenceStyle); } /** * 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 class name of a fragment to be shown when this Preference is clicked. * * @param fragment The class name of the fragment associated with this Preference. */ public void setFragment(String fragment) { mFragment = fragment; } /** * Return the fragment class name associated with this Preference. * * @return The fragment class name last set via {@link #setFragment} or XML. */ public String getFragment() { return mFragment; } /** * 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. */ public Bundle getExtras() { if (mExtras == null) { mExtras = new Bundle(); } return mExtras; } /** * Return the extras Bundle object associated with this preference, * returning null if there is not currently one. */ public Bundle peekExtras() { return mExtras; } /** * 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}. * <p> * It is an error to change the layout after adding the preference to a {@link PreferenceGroup} * * @param layoutResId The layout resource ID to be inflated and returned as * a {@link View}. * @see #setWidgetLayoutResource(int) */ public void setLayoutResource(int layoutResId) { mLayoutResId = layoutResId; } /** * Gets the layout resource that will be shown as the {@link View} for this Preference. * * @return The layout resource ID. */ public final 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. * <p> * It is an error to change the layout after adding the preference to a {@link PreferenceGroup} * * @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 final int getWidgetLayoutResource() { return mWidgetLayoutResId; } /** * 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 holder 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. */ public void onBindViewHolder(PreferenceViewHolder holder) { holder.itemView.setOnClickListener(mClickListener); final TextView titleView = (TextView) holder.findViewById(android.R.id.title); if (titleView != null) { final CharSequence title = getTitle(); if (!TextUtils.isEmpty(title)) { titleView.setText(title); titleView.setVisibility(View.VISIBLE); } else { titleView.setVisibility(View.GONE); } } final TextView summaryView = (TextView) holder.findViewById(android.R.id.summary); if (summaryView != null) { final CharSequence summary = getSummary(); if (!TextUtils.isEmpty(summary)) { summaryView.setText(summary); summaryView.setVisibility(View.VISIBLE); } else { summaryView.setVisibility(View.GONE); } } final ImageView imageView = (ImageView) holder.findViewById(android.R.id.icon); if (imageView != null) { if (mIconResId != 0 || mIcon != null) { if (mIcon == null) { mIcon = ContextCompat.getDrawable(getContext(), mIconResId); } if (mIcon != null) { imageView.setImageDrawable(mIcon); } } imageView.setVisibility(mIcon != null ? View.VISIBLE : View.GONE); } final View imageFrame = holder.findViewById(R.id.icon_frame); if (imageFrame != null) { imageFrame.setVisibility(mIcon != null ? View.VISIBLE : View.GONE); } if (mShouldDisableView) { setEnabledStateOnViews(holder.itemView, isEnabled()); } else { setEnabledStateOnViews(holder.itemView, true); } final boolean selectable = isSelectable(); holder.itemView.setFocusable(selectable); holder.setDividerAllowedAbove(selectable); holder.setDividerAllowedBelow(selectable); } /** * 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 bound by * {@link #onBindViewHolder(PreferenceViewHolder)}. * * @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; } /** * Sets the icon for this Preference with a Drawable. * This icon will be placed into the ID * {@link android.R.id#icon} within the View created by * {@link #onBindViewHolder(PreferenceViewHolder)}. * * @param icon The optional icon for this Preference. */ public void setIcon(Drawable icon) { if ((icon == null && mIcon != null) || (icon != null && mIcon != icon)) { mIcon = icon; mIconResId = 0; notifyChanged(); } } /** * Sets the icon for this Preference with a resource ID. * * @see #setIcon(Drawable) * @param iconResId The icon as a resource ID. */ public void setIcon(int iconResId) { setIcon(ContextCompat.getDrawable(mContext, iconResId)); mIconResId = iconResId; } /** * Returns the icon of this Preference. * * @return The icon. * @see #setIcon(Drawable) */ public Drawable getIcon() { return mIcon; } /** * 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 && mDependencyMet && mParentDependencyMet; } /** * 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; } /** * Sets whether this preference should be visible in the list. If false, it is excluded from * the adapter, but can still be retrieved using * {@link PreferenceFragment#findPreference(CharSequence)}. * * @param visible Set false if this preference should be hidden from the list. */ public final void setVisible(boolean visible) { if (mVisible != visible) { mVisible = visible; if (mListener != null) { mListener.onPreferenceVisibilityChange(this); } } } /** * Checks whether this preference should be visible to the user in the list. * @see #setVisible(boolean) * @return True if this preference should be displayed. */ public final boolean isVisible() { return mVisible; } /** * 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 android.content.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 android.content.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 android.content.SharedPreferences}. * * @throws IllegalStateException If there is no key assigned. */ void requireKey() { if (TextUtils.isEmpty(mKey)) { 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 android.content.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 android.content.SharedPreferences}. This, at minimum, checks whether this * Preference is persistent and it currently has a key. Before you * save/restore from the {@link android.content.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 android.content.SharedPreferences} * storage. * * @param persistent Set true if it should store its value(s) into the * {@link android.content.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). */ public boolean callChangeListener(Object newValue) { return mOnChangeListener == null || 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; } /** * @hide */ protected void performClick(View view) { performClick(); } /** * Called when a click should be performed. * * @hide */ public void performClick() { if (!isEnabled()) { return; } onClick(); if (mOnClickListener != null && mOnClickListener.onPreferenceClick(this)) { return; } PreferenceManager preferenceManager = getPreferenceManager(); if (preferenceManager != null) { PreferenceManager.OnPreferenceTreeClickListener listener = preferenceManager .getOnPreferenceTreeClickListener(); if (listener != null && listener.onPreferenceTreeClick(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 PreferenceFragment}). This Context will be used to save the Preference values. * * @return The Context of this Preference. */ public Context getContext() { return mContext; } /** * Returns the {@link android.content.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)}. * @return The {@link android.content.SharedPreferences} where this Preference reads its * value(s), or null if it isn't attached to a Preference hierarchy. */ public SharedPreferences getSharedPreferences() { if (mPreferenceManager == null) { return null; } return mPreferenceManager.getSharedPreferences(); } /** * 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>. */ @Override public int compareTo(@NonNull Preference another) { if (mOrder != another.mOrder) { // Do order comparison return mOrder - another.mOrder; } else if (mTitle == another.mTitle) { // If titles are null or share same object comparison return 0; } else if (mTitle == null) { return 1; } else if (another.mTitle == null) { return -1; } else { // Do name comparison return mTitle.toString().compareToIgnoreCase(another.mTitle.toString()); } } /** * 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 * 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. */ public void onAttached() { // 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) { if (mDependencyMet == disableDependent) { mDependencyMet = !disableDependent; // Enabled state can change dependent preferences' states, so notify notifyDependencyChange(shouldDisableDependents()); notifyChanged(); } } /** * Called when the implicit parent dependency changes. * * @param parent The Preference that this Preference depends on. * @param disableChild Set true to disable this Preference. */ public void onParentChanged(Preference parent, boolean disableChild) { if (mParentDependencyMet == disableChild) { mParentDependencyMet = !disableChild; // Enabled state can change dependent preferences' states, so notify notifyDependencyChange(shouldDisableDependents()); notifyChanged(); } } /** * 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; } public Object getDefaultValue() { return mDefaultValue; } 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(@NonNull SharedPreferences.Editor editor) { if (mPreferenceManager.shouldCommit()) { SharedPreferencesCompat.EditorCompat.getInstance().apply(editor); } } /** * 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); } @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(' '); } if (sb.length() > 0) { // 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]; } }; } }