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_DOWN) {
100            return false;
101        }
102
103        SeekBar seekBar = (SeekBar) v.findViewById(com.android.internal.R.id.seekbar);
104        if (seekBar == null) {
105            return false;
106        }
107        return seekBar.onKeyDown(keyCode, event);
108    }
109
110    public void setMax(int max) {
111        if (max != mMax) {
112            mMax = max;
113            notifyChanged();
114        }
115    }
116
117    public void setProgress(int progress) {
118        setProgress(progress, true);
119    }
120
121    private void setProgress(int progress, boolean notifyChanged) {
122        if (progress > mMax) {
123            progress = mMax;
124        }
125        if (progress < 0) {
126            progress = 0;
127        }
128        if (progress != mProgress) {
129            mProgress = progress;
130            persistInt(progress);
131            if (notifyChanged) {
132                notifyChanged();
133            }
134        }
135    }
136
137    public int getProgress() {
138        return mProgress;
139    }
140
141    /**
142     * Persist the seekBar's progress value if callChangeListener
143     * returns true, otherwise set the seekBar's progress to the stored value
144     */
145    void syncProgress(SeekBar seekBar) {
146        int progress = seekBar.getProgress();
147        if (progress != mProgress) {
148            if (callChangeListener(progress)) {
149                setProgress(progress, false);
150            } else {
151                seekBar.setProgress(mProgress);
152            }
153        }
154    }
155
156    @Override
157    public void onProgressChanged(
158            SeekBar seekBar, int progress, boolean fromUser) {
159        if (fromUser && !mTrackingTouch) {
160            syncProgress(seekBar);
161        }
162    }
163
164    @Override
165    public void onStartTrackingTouch(SeekBar seekBar) {
166        mTrackingTouch = true;
167    }
168
169    @Override
170    public void onStopTrackingTouch(SeekBar seekBar) {
171        mTrackingTouch = false;
172        if (seekBar.getProgress() != mProgress) {
173            syncProgress(seekBar);
174        }
175    }
176
177    @Override
178    protected Parcelable onSaveInstanceState() {
179        /*
180         * Suppose a client uses this preference type without persisting. We
181         * must save the instance state so it is able to, for example, survive
182         * orientation changes.
183         */
184
185        final Parcelable superState = super.onSaveInstanceState();
186        if (isPersistent()) {
187            // No need to save instance state since it's persistent
188            return superState;
189        }
190
191        // Save the instance state
192        final SavedState myState = new SavedState(superState);
193        myState.progress = mProgress;
194        myState.max = mMax;
195        return myState;
196    }
197
198    @Override
199    protected void onRestoreInstanceState(Parcelable state) {
200        if (!state.getClass().equals(SavedState.class)) {
201            // Didn't save state for us in onSaveInstanceState
202            super.onRestoreInstanceState(state);
203            return;
204        }
205
206        // Restore the instance state
207        SavedState myState = (SavedState) state;
208        super.onRestoreInstanceState(myState.getSuperState());
209        mProgress = myState.progress;
210        mMax = myState.max;
211        notifyChanged();
212    }
213
214    /**
215     * SavedState, a subclass of {@link BaseSavedState}, will store the state
216     * of MyPreference, a subclass of Preference.
217     * <p>
218     * It is important to always call through to super methods.
219     */
220    private static class SavedState extends BaseSavedState {
221        int progress;
222        int max;
223
224        public SavedState(Parcel source) {
225            super(source);
226
227            // Restore the click counter
228            progress = source.readInt();
229            max = source.readInt();
230        }
231
232        @Override
233        public void writeToParcel(Parcel dest, int flags) {
234            super.writeToParcel(dest, flags);
235
236            // Save the click counter
237            dest.writeInt(progress);
238            dest.writeInt(max);
239        }
240
241        public SavedState(Parcelable superState) {
242            super(superState);
243        }
244
245        @SuppressWarnings("unused")
246        public static final Parcelable.Creator<SavedState> CREATOR =
247                new Parcelable.Creator<SavedState>() {
248            public SavedState createFromParcel(Parcel in) {
249                return new SavedState(in);
250            }
251
252            public SavedState[] newArray(int size) {
253                return new SavedState[size];
254            }
255        };
256    }
257}
258