/*
* Copyright (C) 2010 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 android.annotation.ArrayRes;
import android.app.AlertDialog.Builder;
import android.content.Context;
import android.content.DialogInterface;
import android.content.res.TypedArray;
import android.os.Parcel;
import android.os.Parcelable;
import android.util.AttributeSet;
import java.util.HashSet;
import java.util.Set;
/**
* A {@link Preference} that displays a list of entries as
* a dialog.
* <p>
* This preference will store a set of strings into the SharedPreferences.
* This set will contain one or more values from the
* {@link #setEntryValues(CharSequence[])} array.
*
* @attr ref android.R.styleable#MultiSelectListPreference_entries
* @attr ref android.R.styleable#MultiSelectListPreference_entryValues
*/
public class MultiSelectListPreference extends DialogPreference {
private CharSequence[] mEntries;
private CharSequence[] mEntryValues;
private Set<String> mValues = new HashSet<String>();
private Set<String> mNewValues = new HashSet<String>();
private boolean mPreferenceChanged;
public MultiSelectListPreference(
Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
super(context, attrs, defStyleAttr, defStyleRes);
final TypedArray a = context.obtainStyledAttributes(attrs,
com.android.internal.R.styleable.MultiSelectListPreference, defStyleAttr,
defStyleRes);
mEntries = a.getTextArray(com.android.internal.R.styleable.MultiSelectListPreference_entries);
mEntryValues = a.getTextArray(com.android.internal.R.styleable.MultiSelectListPreference_entryValues);
a.recycle();
}
public MultiSelectListPreference(Context context, AttributeSet attrs, int defStyleAttr) {
this(context, attrs, defStyleAttr, 0);
}
public MultiSelectListPreference(Context context, AttributeSet attrs) {
this(context, attrs, com.android.internal.R.attr.dialogPreferenceStyle);
}
public MultiSelectListPreference(Context context) {
this(context, null);
}
/**
* Sets the human-readable entries to be shown in the list. This will be
* shown in subsequent dialogs.
* <p>
* Each entry must have a corresponding index in
* {@link #setEntryValues(CharSequence[])}.
*
* @param entries The entries.
* @see #setEntryValues(CharSequence[])
*/
public void setEntries(CharSequence[] entries) {
mEntries = entries;
}
/**
* @see #setEntries(CharSequence[])
* @param entriesResId The entries array as a resource.
*/
public void setEntries(@ArrayRes int entriesResId) {
setEntries(getContext().getResources().getTextArray(entriesResId));
}
/**
* The list of entries to be shown in the list in subsequent dialogs.
*
* @return The list as an array.
*/
public CharSequence[] getEntries() {
return mEntries;
}
/**
* The array to find the value to save for a preference when an entry from
* entries is selected. If a user clicks on the second item in entries, the
* second item in this array will be saved to the preference.
*
* @param entryValues The array to be used as values to save for the preference.
*/
public void setEntryValues(CharSequence[] entryValues) {
mEntryValues = entryValues;
}
/**
* @see #setEntryValues(CharSequence[])
* @param entryValuesResId The entry values array as a resource.
*/
public void setEntryValues(@ArrayRes int entryValuesResId) {
setEntryValues(getContext().getResources().getTextArray(entryValuesResId));
}
/**
* Returns the array of values to be saved for the preference.
*
* @return The array of values.
*/
public CharSequence[] getEntryValues() {
return mEntryValues;
}
/**
* Sets the value of the key. This should contain entries in
* {@link #getEntryValues()}.
*
* @param values The values to set for the key.
*/
public void setValues(Set<String> values) {
mValues.clear();
mValues.addAll(values);
persistStringSet(values);
}
/**
* Retrieves the current value of the key.
*/
public Set<String> getValues() {
return mValues;
}
/**
* Returns the index of the given value (in the entry values array).
*
* @param value The value whose index should be returned.
* @return The index of the value, or -1 if not found.
*/
public int findIndexOfValue(String value) {
if (value != null && mEntryValues != null) {
for (int i = mEntryValues.length - 1; i >= 0; i--) {
if (mEntryValues[i].equals(value)) {
return i;
}
}
}
return -1;
}
@Override
protected void onPrepareDialogBuilder(Builder builder) {
super.onPrepareDialogBuilder(builder);
if (mEntries == null || mEntryValues == null) {
throw new IllegalStateException(
"MultiSelectListPreference requires an entries array and " +
"an entryValues array.");
}
boolean[] checkedItems = getSelectedItems();
builder.setMultiChoiceItems(mEntries, checkedItems,
new DialogInterface.OnMultiChoiceClickListener() {
public void onClick(DialogInterface dialog, int which, boolean isChecked) {
if (isChecked) {
mPreferenceChanged |= mNewValues.add(mEntryValues[which].toString());
} else {
mPreferenceChanged |= mNewValues.remove(mEntryValues[which].toString());
}
}
});
mNewValues.clear();
mNewValues.addAll(mValues);
}
private boolean[] getSelectedItems() {
final CharSequence[] entries = mEntryValues;
final int entryCount = entries.length;
final Set<String> values = mValues;
boolean[] result = new boolean[entryCount];
for (int i = 0; i < entryCount; i++) {
result[i] = values.contains(entries[i].toString());
}
return result;
}
@Override
protected void onDialogClosed(boolean positiveResult) {
super.onDialogClosed(positiveResult);
if (positiveResult && mPreferenceChanged) {
final Set<String> values = mNewValues;
if (callChangeListener(values)) {
setValues(values);
}
}
mPreferenceChanged = false;
}
@Override
protected Object onGetDefaultValue(TypedArray a, int index) {
final CharSequence[] defaultValues = a.getTextArray(index);
final int valueCount = defaultValues.length;
final Set<String> result = new HashSet<String>();
for (int i = 0; i < valueCount; i++) {
result.add(defaultValues[i].toString());
}
return result;
}
@Override
protected void onSetInitialValue(boolean restoreValue, Object defaultValue) {
setValues(restoreValue ? getPersistedStringSet(mValues) : (Set<String>) defaultValue);
}
@Override
protected Parcelable onSaveInstanceState() {
final Parcelable superState = super.onSaveInstanceState();
if (isPersistent()) {
// No need to save instance state
return superState;
}
final SavedState myState = new SavedState(superState);
myState.values = getValues();
return myState;
}
private static class SavedState extends BaseSavedState {
Set<String> values;
public SavedState(Parcel source) {
super(source);
values = new HashSet<String>();
String[] strings = source.readStringArray();
final int stringCount = strings.length;
for (int i = 0; i < stringCount; i++) {
values.add(strings[i]);
}
}
public SavedState(Parcelable superState) {
super(superState);
}
@Override
public void writeToParcel(Parcel dest, int flags) {
super.writeToParcel(dest, flags);
dest.writeStringArray(values.toArray(new String[0]));
}
public static final Parcelable.Creator<SavedState> CREATOR =
new Parcelable.Creator<SavedState>() {
public SavedState createFromParcel(Parcel in) {
return new SavedState(in);
}
public SavedState[] newArray(int size) {
return new SavedState[size];
}
};
}
}