| /* |
| * 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 com.example.android.apis.preference; |
| |
| import com.example.android.apis.R; |
| |
| import android.content.Context; |
| import android.content.res.TypedArray; |
| import android.os.Parcel; |
| import android.os.Parcelable; |
| import android.preference.Preference; |
| import android.util.AttributeSet; |
| import android.view.View; |
| import android.widget.TextView; |
| |
| /** |
| * This is an example of a custom preference type. The preference counts the |
| * number of clicks it has received and stores/retrieves it from the storage. |
| */ |
| public class MyPreference extends Preference { |
| private int mClickCounter; |
| |
| // This is the constructor called by the inflater |
| public MyPreference(Context context, AttributeSet attrs) { |
| super(context, attrs); |
| |
| setWidgetLayoutResource(R.layout.preference_widget_mypreference); |
| } |
| |
| @Override |
| protected void onBindView(View view) { |
| super.onBindView(view); |
| |
| // Set our custom views inside the layout |
| final TextView myTextView = (TextView) view.findViewById(R.id.mypreference_widget); |
| if (myTextView != null) { |
| myTextView.setText(String.valueOf(mClickCounter)); |
| } |
| } |
| |
| @Override |
| protected void onClick() { |
| int newValue = mClickCounter + 1; |
| // Give the client a chance to ignore this change if they deem it |
| // invalid |
| if (!callChangeListener(newValue)) { |
| // They don't want the value to be set |
| return; |
| } |
| |
| // Increment counter |
| mClickCounter = newValue; |
| |
| // Save to persistent storage (this method will make sure this |
| // preference should be persistent, along with other useful checks) |
| persistInt(mClickCounter); |
| |
| // Data has changed, notify so UI can be refreshed! |
| notifyChanged(); |
| } |
| |
| @Override |
| protected Object onGetDefaultValue(TypedArray a, int index) { |
| // This preference type's value type is Integer, so we read the default |
| // value from the attributes as an Integer. |
| return a.getInteger(index, 0); |
| } |
| |
| @Override |
| protected void onSetInitialValue(boolean restoreValue, Object defaultValue) { |
| if (restoreValue) { |
| // Restore state |
| mClickCounter = getPersistedInt(mClickCounter); |
| } else { |
| // Set state |
| int value = (Integer) defaultValue; |
| mClickCounter = value; |
| persistInt(value); |
| } |
| } |
| |
| @Override |
| protected Parcelable onSaveInstanceState() { |
| /* |
| * Suppose a client uses this preference type without persisting. We |
| * must save the instance state so it is able to, for example, survive |
| * orientation changes. |
| */ |
| |
| final Parcelable superState = super.onSaveInstanceState(); |
| if (isPersistent()) { |
| // No need to save instance state since it's persistent |
| return superState; |
| } |
| |
| // Save the instance state |
| final SavedState myState = new SavedState(superState); |
| myState.clickCounter = mClickCounter; |
| return myState; |
| } |
| |
| @Override |
| protected void onRestoreInstanceState(Parcelable state) { |
| if (!state.getClass().equals(SavedState.class)) { |
| // Didn't save state for us in onSaveInstanceState |
| super.onRestoreInstanceState(state); |
| return; |
| } |
| |
| // Restore the instance state |
| SavedState myState = (SavedState) state; |
| super.onRestoreInstanceState(myState.getSuperState()); |
| mClickCounter = myState.clickCounter; |
| notifyChanged(); |
| } |
| |
| /** |
| * SavedState, a subclass of {@link BaseSavedState}, will store the state |
| * of MyPreference, a subclass of Preference. |
| * <p> |
| * It is important to always call through to super methods. |
| */ |
| private static class SavedState extends BaseSavedState { |
| int clickCounter; |
| |
| public SavedState(Parcel source) { |
| super(source); |
| |
| // Restore the click counter |
| clickCounter = source.readInt(); |
| } |
| |
| @Override |
| public void writeToParcel(Parcel dest, int flags) { |
| super.writeToParcel(dest, flags); |
| |
| // Save the click counter |
| dest.writeInt(clickCounter); |
| } |
| |
| 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]; |
| } |
| }; |
| } |
| |
| } |