1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package android.preference;
18
19import android.content.Context;
20import android.content.res.TypedArray;
21import android.os.Parcel;
22import android.os.Parcelable;
23import android.util.AttributeSet;
24import android.view.KeyEvent;
25import android.view.View;
26import android.widget.SeekBar;
27import android.widget.SeekBar.OnSeekBarChangeListener;
28
29/**
30 * @hide
31 */
32public class SeekBarPreference extends Preference
33        implements OnSeekBarChangeListener {
34
35    private int mProgress;
36    private int mMax;
37    private boolean mTrackingTouch;
38
39    public SeekBarPreference(
40            Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
41        super(context, attrs, defStyleAttr, defStyleRes);
42
43        TypedArray a = context.obtainStyledAttributes(
44                attrs, com.android.internal.R.styleable.ProgressBar, defStyleAttr, defStyleRes);
45        setMax(a.getInt(com.android.internal.R.styleable.ProgressBar_max, mMax));
46        a.recycle();
47
48        a = context.obtainStyledAttributes(attrs,
49                com.android.internal.R.styleable.SeekBarPreference, defStyleAttr, defStyleRes);
50        final int layoutResId = a.getResourceId(
51                com.android.internal.R.styleable.SeekBarPreference_layout,
52                com.android.internal.R.layout.preference_widget_seekbar);
53        a.recycle();
54
55        setLayoutResource(layoutResId);
56    }
57
58    public SeekBarPreference(Context context, AttributeSet attrs, int defStyleAttr) {
59        this(context, attrs, defStyleAttr, 0);
60    }
61
62    public SeekBarPreference(Context context, AttributeSet attrs) {
63        this(context, attrs, com.android.internal.R.attr.seekBarPreferenceStyle);
64    }
65
66    public SeekBarPreference(Context context) {
67        this(context, null);
68    }
69
70    @Override
71    protected void onBindView(View view) {
72        super.onBindView(view);
73        SeekBar seekBar = (SeekBar) view.findViewById(
74                com.android.internal.R.id.seekbar);
75        seekBar.setOnSeekBarChangeListener(this);
76        seekBar.setMax(mMax);
77        seekBar.setProgress(mProgress);
78        seekBar.setEnabled(isEnabled());
79    }
80
81    @Override
82    public CharSequence getSummary() {
83        return null;
84    }
85
86    @Override
87    protected void onSetInitialValue(boolean restoreValue, Object defaultValue) {
88        setProgress(restoreValue ? getPersistedInt(mProgress)
89                : (Integer) defaultValue);
90    }
91
92    @Override
93    protected Object onGetDefaultValue(TypedArray a, int index) {
94        return a.getInt(index, 0);
95    }
96
97    @Override
98    public boolean onKey(View v, int keyCode, KeyEvent event) {
99        if (event.getAction() != KeyEvent.ACTION_UP) {
100            if (keyCode == KeyEvent.KEYCODE_PLUS
101                    || keyCode == KeyEvent.KEYCODE_EQUALS) {
102                setProgress(getProgress() + 1);
103                return true;
104            }
105            if (keyCode == KeyEvent.KEYCODE_MINUS) {
106                setProgress(getProgress() - 1);
107                return true;
108            }
109        }
110        return false;
111    }
112
113    public void setMax(int max) {
114        if (max != mMax) {
115            mMax = max;
116            notifyChanged();
117        }
118    }
119
120    public void setProgress(int progress) {
121        setProgress(progress, true);
122    }
123
124    private void setProgress(int progress, boolean notifyChanged) {
125        if (progress > mMax) {
126            progress = mMax;
127        }
128        if (progress < 0) {
129            progress = 0;
130        }
131        if (progress != mProgress) {
132            mProgress = progress;
133            persistInt(progress);
134            if (notifyChanged) {
135                notifyChanged();
136            }
137        }
138    }
139
140    public int getProgress() {
141        return mProgress;
142    }
143
144    /**
145     * Persist the seekBar's progress value if callChangeListener
146     * returns true, otherwise set the seekBar's progress to the stored value
147     */
148    void syncProgress(SeekBar seekBar) {
149        int progress = seekBar.getProgress();
150        if (progress != mProgress) {
151            if (callChangeListener(progress)) {
152                setProgress(progress, false);
153            } else {
154                seekBar.setProgress(mProgress);
155            }
156        }
157    }
158
159    @Override
160    public void onProgressChanged(
161            SeekBar seekBar, int progress, boolean fromUser) {
162        if (fromUser && !mTrackingTouch) {
163            syncProgress(seekBar);
164        }
165    }
166
167    @Override
168    public void onStartTrackingTouch(SeekBar seekBar) {
169        mTrackingTouch = true;
170    }
171
172    @Override
173    public void onStopTrackingTouch(SeekBar seekBar) {
174        mTrackingTouch = false;
175        if (seekBar.getProgress() != mProgress) {
176            syncProgress(seekBar);
177        }
178    }
179
180    @Override
181    protected Parcelable onSaveInstanceState() {
182        /*
183         * Suppose a client uses this preference type without persisting. We
184         * must save the instance state so it is able to, for example, survive
185         * orientation changes.
186         */
187
188        final Parcelable superState = super.onSaveInstanceState();
189        if (isPersistent()) {
190            // No need to save instance state since it's persistent
191            return superState;
192        }
193
194        // Save the instance state
195        final SavedState myState = new SavedState(superState);
196        myState.progress = mProgress;
197        myState.max = mMax;
198        return myState;
199    }
200
201    @Override
202    protected void onRestoreInstanceState(Parcelable state) {
203        if (!state.getClass().equals(SavedState.class)) {
204            // Didn't save state for us in onSaveInstanceState
205            super.onRestoreInstanceState(state);
206            return;
207        }
208
209        // Restore the instance state
210        SavedState myState = (SavedState) state;
211        super.onRestoreInstanceState(myState.getSuperState());
212        mProgress = myState.progress;
213        mMax = myState.max;
214        notifyChanged();
215    }
216
217    /**
218     * SavedState, a subclass of {@link BaseSavedState}, will store the state
219     * of MyPreference, a subclass of Preference.
220     * <p>
221     * It is important to always call through to super methods.
222     */
223    private static class SavedState extends BaseSavedState {
224        int progress;
225        int max;
226
227        public SavedState(Parcel source) {
228            super(source);
229
230            // Restore the click counter
231            progress = source.readInt();
232            max = source.readInt();
233        }
234
235        @Override
236        public void writeToParcel(Parcel dest, int flags) {
237            super.writeToParcel(dest, flags);
238
239            // Save the click counter
240            dest.writeInt(progress);
241            dest.writeInt(max);
242        }
243
244        public SavedState(Parcelable superState) {
245            super(superState);
246        }
247
248        @SuppressWarnings("unused")
249        public static final Parcelable.Creator<SavedState> CREATOR =
250                new Parcelable.Creator<SavedState>() {
251            public SavedState createFromParcel(Parcel in) {
252                return new SavedState(in);
253            }
254
255            public SavedState[] newArray(int size) {
256                return new SavedState[size];
257            }
258        };
259    }
260}
261