/*
* 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 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;
/**
* A {@link Preference} that displays a list of entries as
* a dialog.
* <p>
* This preference will store a string into the SharedPreferences. This string will be the value
* from the {@link #setEntryValues(CharSequence[])} array.
*
* @attr ref android.R.styleable#ListPreference_entries
* @attr ref android.R.styleable#ListPreference_entryValues
*/
public class ListPreference extends DialogPreference {
private CharSequence[] mEntries;
private CharSequence[] mEntryValues;
private String mValue;
private int mClickedDialogEntryIndex;
public ListPreference(Context context, AttributeSet attrs) {
super(context, attrs);
TypedArray a = context.obtainStyledAttributes(attrs,
com.android.internal.R.styleable.ListPreference, 0, 0);
mEntries = a.getTextArray(com.android.internal.R.styleable.ListPreference_entries);
mEntryValues = a.getTextArray(com.android.internal.R.styleable.ListPreference_entryValues);
a.recycle();
}
public ListPreference(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(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(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 be one of the entries in
* {@link #getEntryValues()}.
*
* @param value The value to set for the key.
*/
public void setValue(String value) {
mValue = value;
persistString(value);
}
/**
* Sets the value to the given index from the entry values.
*
* @param index The index of the value to set.
*/
public void setValueIndex(int index) {
if (mEntryValues != null) {
setValue(mEntryValues[index].toString());
}
}
/**
* Returns the value of the key. This should be one of the entries in
* {@link #getEntryValues()}.
*
* @return The value of the key.
*/
public String getValue() {
return mValue;
}
/**
* Returns the entry corresponding to the current value.
*
* @return The entry corresponding to the current value, or null.
*/
public CharSequence getEntry() {
int index = getValueIndex();
return index >= 0 && mEntries != null ? mEntries[index] : null;
}
/**
* 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;
}
private int getValueIndex() {
return findIndexOfValue(mValue);
}
@Override
protected void onPrepareDialogBuilder(Builder builder) {
super.onPrepareDialogBuilder(builder);
if (mEntries == null || mEntryValues == null) {
throw new IllegalStateException(
"ListPreference requires an entries array and an entryValues array.");
}
mClickedDialogEntryIndex = getValueIndex();
builder.setSingleChoiceItems(mEntries, mClickedDialogEntryIndex,
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
mClickedDialogEntryIndex = which;
/*
* Clicking on an item simulates the positive button
* click, and dismisses the dialog.
*/
ListPreference.this.onClick(dialog, DialogInterface.BUTTON_POSITIVE);
dialog.dismiss();
}
});
/*
* The typical interaction for list-based dialogs is to have
* click-on-an-item dismiss the dialog instead of the user having to
* press 'Ok'.
*/
builder.setPositiveButton(null, null);
}
@Override
protected void onDialogClosed(boolean positiveResult) {
super.onDialogClosed(positiveResult);
if (positiveResult && mClickedDialogEntryIndex >= 0 && mEntryValues != null) {
String value = mEntryValues[mClickedDialogEntryIndex].toString();
if (callChangeListener(value)) {
setValue(value);
}
}
}
@Override
protected Object onGetDefaultValue(TypedArray a, int index) {
return a.getString(index);
}
@Override
protected void onSetInitialValue(boolean restoreValue, Object defaultValue) {
setValue(restoreValue ? getPersistedString(mValue) : (String) defaultValue);
}
@Override
protected Parcelable onSaveInstanceState() {
final Parcelable superState = super.onSaveInstanceState();
if (isPersistent()) {
// No need to save instance state since it's persistent
return superState;
}
final SavedState myState = new SavedState(superState);
myState.value = getValue();
return myState;
}
@Override
protected void onRestoreInstanceState(Parcelable state) {
if (state == null || !state.getClass().equals(SavedState.class)) {
// Didn't save state for us in onSaveInstanceState
super.onRestoreInstanceState(state);
return;
}
SavedState myState = (SavedState) state;
super.onRestoreInstanceState(myState.getSuperState());
setValue(myState.value);
}
private static class SavedState extends BaseSavedState {
String value;
public SavedState(Parcel source) {
super(source);
value = source.readString();
}
@Override
public void writeToParcel(Parcel dest, int flags) {
super.writeToParcel(dest, flags);
dest.writeString(value);
}
public SavedState(Parcelable superState) {
super(superState);
}
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];
}
};
}
}
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