/*
* 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.content.Context;
import android.content.SharedPreferences;
import android.content.res.TypedArray;
import android.os.Parcel;
import android.os.Parcelable;
import android.util.AttributeSet;
import android.view.View;
import android.view.accessibility.AccessibilityEvent;
import android.view.accessibility.AccessibilityManager;
import android.widget.TextView;
/**
* Common base class for preferences that have two selectable states, persist a
* boolean value in SharedPreferences, and may have dependent preferences that are
* enabled/disabled based on the current state.
*/
public abstract class TwoStatePreference extends Preference {
private CharSequence mSummaryOn;
private CharSequence mSummaryOff;
boolean mChecked;
private boolean mCheckedSet;
private boolean mSendClickAccessibilityEvent;
private boolean mDisableDependentsState;
public TwoStatePreference(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
public TwoStatePreference(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public TwoStatePreference(Context context) {
this(context, null);
}
@Override
protected void onClick() {
super.onClick();
boolean newValue = !isChecked();
mSendClickAccessibilityEvent = true;
if (!callChangeListener(newValue)) {
return;
}
setChecked(newValue);
}
/**
* Sets the checked state and saves it to the {@link SharedPreferences}.
*
* @param checked The checked state.
*/
public void setChecked(boolean checked) {
// Always persist/notify the first time; don't assume the field's default of false.
final boolean changed = mChecked != checked;
if (changed || !mCheckedSet) {
mChecked = checked;
mCheckedSet = true;
persistBoolean(checked);
if (changed) {
notifyDependencyChange(shouldDisableDependents());
notifyChanged();
}
}
}
/**
* Returns the checked state.
*
* @return The checked state.
*/
public boolean isChecked() {
return mChecked;
}
@Override
public boolean shouldDisableDependents() {
boolean shouldDisable = mDisableDependentsState ? mChecked : !mChecked;
return shouldDisable || super.shouldDisableDependents();
}
/**
* Sets the summary to be shown when checked.
*
* @param summary The summary to be shown when checked.
*/
public void setSummaryOn(CharSequence summary) {
mSummaryOn = summary;
if (isChecked()) {
notifyChanged();
}
}
/**
* @see #setSummaryOn(CharSequence)
* @param summaryResId The summary as a resource.
*/
public void setSummaryOn(int summaryResId) {
setSummaryOn(getContext().getString(summaryResId));
}
/**
* Returns the summary to be shown when checked.
* @return The summary.
*/
public CharSequence getSummaryOn() {
return mSummaryOn;
}
/**
* Sets the summary to be shown when unchecked.
*
* @param summary The summary to be shown when unchecked.
*/
public void setSummaryOff(CharSequence summary) {
mSummaryOff = summary;
if (!isChecked()) {
notifyChanged();
}
}
/**
* @see #setSummaryOff(CharSequence)
* @param summaryResId The summary as a resource.
*/
public void setSummaryOff(int summaryResId) {
setSummaryOff(getContext().getString(summaryResId));
}
/**
* Returns the summary to be shown when unchecked.
* @return The summary.
*/
public CharSequence getSummaryOff() {
return mSummaryOff;
}
/**
* Returns whether dependents are disabled when this preference is on ({@code true})
* or when this preference is off ({@code false}).
*
* @return Whether dependents are disabled when this preference is on ({@code true})
* or when this preference is off ({@code false}).
*/
public boolean getDisableDependentsState() {
return mDisableDependentsState;
}
/**
* Sets whether dependents are disabled when this preference is on ({@code true})
* or when this preference is off ({@code false}).
*
* @param disableDependentsState The preference state that should disable dependents.
*/
public void setDisableDependentsState(boolean disableDependentsState) {
mDisableDependentsState = disableDependentsState;
}
@Override
protected Object onGetDefaultValue(TypedArray a, int index) {
return a.getBoolean(index, false);
}
@Override
protected void onSetInitialValue(boolean restoreValue, Object defaultValue) {
setChecked(restoreValue ? getPersistedBoolean(mChecked)
: (Boolean) defaultValue);
}
void sendAccessibilityEvent(View view) {
// Since the view is still not attached we create, populate,
// and send the event directly since we do not know when it
// will be attached and posting commands is not as clean.
AccessibilityManager accessibilityManager = AccessibilityManager.getInstance(getContext());
if (mSendClickAccessibilityEvent && accessibilityManager.isEnabled()) {
AccessibilityEvent event = AccessibilityEvent.obtain();
event.setEventType(AccessibilityEvent.TYPE_VIEW_CLICKED);
view.onInitializeAccessibilityEvent(event);
view.dispatchPopulateAccessibilityEvent(event);
accessibilityManager.sendAccessibilityEvent(event);
}
mSendClickAccessibilityEvent = false;
}
/**
* Sync a summary view contained within view's subhierarchy with the correct summary text.
* @param view View where a summary should be located
*/
void syncSummaryView(View view) {
// Sync the summary view
TextView summaryView = (TextView) view.findViewById(com.android.internal.R.id.summary);
if (summaryView != null) {
boolean useDefaultSummary = true;
if (mChecked && mSummaryOn != null) {
summaryView.setText(mSummaryOn);
useDefaultSummary = false;
} else if (!mChecked && mSummaryOff != null) {
summaryView.setText(mSummaryOff);
useDefaultSummary = false;
}
if (useDefaultSummary) {
final CharSequence summary = getSummary();
if (summary != null) {
summaryView.setText(summary);
useDefaultSummary = false;
}
}
int newVisibility = View.GONE;
if (!useDefaultSummary) {
// Someone has written to it
newVisibility = View.VISIBLE;
}
if (newVisibility != summaryView.getVisibility()) {
summaryView.setVisibility(newVisibility);
}
}
}
@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.checked = isChecked();
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());
setChecked(myState.checked);
}
static class SavedState extends BaseSavedState {
boolean checked;
public SavedState(Parcel source) {
super(source);
checked = source.readInt() == 1;
}
@Override
public void writeToParcel(Parcel dest, int flags) {
super.writeToParcel(dest, flags);
dest.writeInt(checked ? 1 : 0);
}
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];
}
};
}
}