/*
* 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.Collections;
import java.util.List;
import java.util.Map;
import android.content.Context;
import android.content.res.TypedArray;
import android.os.Bundle;
import android.os.Parcelable;
import android.text.TextUtils;
import android.util.AttributeSet;
/**
* A container for multiple
* {@link Preference} objects. It is a base class for Preference objects that are
* parents, such as {@link PreferenceCategory} and {@link PreferenceScreen}.
*
* <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#PreferenceGroup_orderingFromXml
*/
public abstract class PreferenceGroup extends Preference implements GenericInflater.Parent<Preference> {
/**
* The container for child {@link Preference}s. This is sorted based on the
* ordering, please use {@link #addPreference(Preference)} instead of adding
* to this directly.
*/
private List<Preference> mPreferenceList;
private boolean mOrderingAsAdded = true;
private int mCurrentPreferenceOrder = 0;
private boolean mAttachedToActivity = false;
public PreferenceGroup(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
super(context, attrs, defStyleAttr, defStyleRes);
mPreferenceList = new ArrayList<Preference>();
final TypedArray a = context.obtainStyledAttributes(
attrs, com.android.internal.R.styleable.PreferenceGroup, defStyleAttr, defStyleRes);
mOrderingAsAdded = a.getBoolean(com.android.internal.R.styleable.PreferenceGroup_orderingFromXml,
mOrderingAsAdded);
a.recycle();
}
public PreferenceGroup(Context context, AttributeSet attrs, int defStyleAttr) {
this(context, attrs, defStyleAttr, 0);
}
public PreferenceGroup(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
/**
* Whether to order the {@link Preference} children of this group as they
* are added. If this is false, the ordering will follow each Preference
* order and default to alphabetic for those without an order.
* <p>
* If this is called after preferences are added, they will not be
* re-ordered in the order they were added, hence call this method early on.
*
* @param orderingAsAdded Whether to order according to the order added.
* @see Preference#setOrder(int)
*/
public void setOrderingAsAdded(boolean orderingAsAdded) {
mOrderingAsAdded = orderingAsAdded;
}
/**
* Whether this group is ordering preferences in the order they are added.
*
* @return Whether this group orders based on the order the children are added.
* @see #setOrderingAsAdded(boolean)
*/
public boolean isOrderingAsAdded() {
return mOrderingAsAdded;
}
/**
* Called by the inflater to add an item to this group.
*/
public void addItemFromInflater(Preference preference) {
addPreference(preference);
}
/**
* Returns the number of children {@link Preference}s.
* @return The number of preference children in this group.
*/
public int getPreferenceCount() {
return mPreferenceList.size();
}
/**
* Returns the {@link Preference} at a particular index.
*
* @param index The index of the {@link Preference} to retrieve.
* @return The {@link Preference}.
*/
public Preference getPreference(int index) {
return mPreferenceList.get(index);
}
/**
* Adds a {@link Preference} at the correct position based on the
* preference's order.
*
* @param preference The preference to add.
* @return Whether the preference is now in this group.
*/
public boolean addPreference(Preference preference) {
if (mPreferenceList.contains(preference)) {
// Exists
return true;
}
if (preference.getOrder() == Preference.DEFAULT_ORDER) {
if (mOrderingAsAdded) {
preference.setOrder(mCurrentPreferenceOrder++);
}
if (preference instanceof PreferenceGroup) {
// TODO: fix (method is called tail recursively when inflating,
// so we won't end up properly passing this flag down to children
((PreferenceGroup)preference).setOrderingAsAdded(mOrderingAsAdded);
}
}
int insertionIndex = Collections.binarySearch(mPreferenceList, preference);
if (insertionIndex < 0) {
insertionIndex = insertionIndex * -1 - 1;
}
if (!onPrepareAddPreference(preference)) {
return false;
}
synchronized(this) {
mPreferenceList.add(insertionIndex, preference);
}
preference.onAttachedToHierarchy(getPreferenceManager());
if (mAttachedToActivity) {
preference.onAttachedToActivity();
}
notifyHierarchyChanged();
return true;
}
/**
* Removes a {@link Preference} from this group.
*
* @param preference The preference to remove.
* @return Whether the preference was found and removed.
*/
public boolean removePreference(Preference preference) {
final boolean returnValue = removePreferenceInt(preference);
notifyHierarchyChanged();
return returnValue;
}
private boolean removePreferenceInt(Preference preference) {
synchronized(this) {
preference.onPrepareForRemoval();
return mPreferenceList.remove(preference);
}
}
/**
* Removes all {@link Preference Preferences} from this group.
*/
public void removeAll() {
synchronized(this) {
List<Preference> preferenceList = mPreferenceList;
for (int i = preferenceList.size() - 1; i >= 0; i--) {
removePreferenceInt(preferenceList.get(0));
}
}
notifyHierarchyChanged();
}
/**
* Prepares a {@link Preference} to be added to the group.
*
* @param preference The preference to add.
* @return Whether to allow adding the preference (true), or not (false).
*/
protected boolean onPrepareAddPreference(Preference preference) {
preference.onParentChanged(this, shouldDisableDependents());
return true;
}
/**
* Finds a {@link Preference} based on its key. If two {@link Preference}
* share the same key (not recommended), the first to appear will be
* returned (to retrieve the other preference with the same key, call this
* method on the first preference). If this preference has the key, it will
* not be returned.
* <p>
* This will recursively search for the preference into children that are
* also {@link PreferenceGroup PreferenceGroups}.
*
* @param key The key of the preference to retrieve.
* @return The {@link Preference} with the key, or null.
*/
public Preference findPreference(CharSequence key) {
if (TextUtils.equals(getKey(), key)) {
return this;
}
final int preferenceCount = getPreferenceCount();
for (int i = 0; i < preferenceCount; i++) {
final Preference preference = getPreference(i);
final String curKey = preference.getKey();
if (curKey != null && curKey.equals(key)) {
return preference;
}
if (preference instanceof PreferenceGroup) {
final Preference returnedPreference = ((PreferenceGroup)preference)
.findPreference(key);
if (returnedPreference != null) {
return returnedPreference;
}
}
}
return null;
}
/**
* Whether this preference group should be shown on the same screen as its
* contained preferences.
*
* @return True if the contained preferences should be shown on the same
* screen as this preference.
*/
protected boolean isOnSameScreenAsChildren() {
return true;
}
@Override
protected void onAttachedToActivity() {
super.onAttachedToActivity();
// Mark as attached so if a preference is later added to this group, we
// can tell it we are already attached
mAttachedToActivity = true;
// Dispatch to all contained preferences
final int preferenceCount = getPreferenceCount();
for (int i = 0; i < preferenceCount; i++) {
getPreference(i).onAttachedToActivity();
}
}
@Override
protected void onPrepareForRemoval() {
super.onPrepareForRemoval();
// We won't be attached to the activity anymore
mAttachedToActivity = false;
}
@Override
public void notifyDependencyChange(boolean disableDependents) {
super.notifyDependencyChange(disableDependents);
// Child preferences have an implicit dependency on their containing
// group. Dispatch dependency change to all contained preferences.
final int preferenceCount = getPreferenceCount();
for (int i = 0; i < preferenceCount; i++) {
getPreference(i).onParentChanged(this, disableDependents);
}
}
void sortPreferences() {
synchronized (this) {
Collections.sort(mPreferenceList);
}
}
@Override
protected void dispatchSaveInstanceState(Bundle container) {
super.dispatchSaveInstanceState(container);
// Dispatch to all contained preferences
final int preferenceCount = getPreferenceCount();
for (int i = 0; i < preferenceCount; i++) {
getPreference(i).dispatchSaveInstanceState(container);
}
}
@Override
protected void dispatchRestoreInstanceState(Bundle container) {
super.dispatchRestoreInstanceState(container);
// Dispatch to all contained preferences
final int preferenceCount = getPreferenceCount();
for (int i = 0; i < preferenceCount; i++) {
getPreference(i).dispatchRestoreInstanceState(container);
}
}
}
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