1 /*
2  * Copyright (C) 2014 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 
17 package android.view;
18 
19 import android.os.Parcel;
20 import android.os.Parcelable;
21 
22 /**
23  * This class contains window animation frame statistics. For example, a window
24  * animation is usually performed when the application is transitioning from one
25  * activity to another. The frame statistics are a snapshot for the time interval
26  * from {@link #getStartTimeNano()} to {@link #getEndTimeNano()}.
27  * <p>
28  * The key idea is that in order to provide a smooth user experience the system should
29  * run window animations at a specific time interval obtained by calling {@link
30  * #getRefreshPeriodNano()}. If the system does not render a frame every refresh
31  * period the user will see irregular window transitions. The time when the frame was
32  * actually presented on the display by calling {@link #getFramePresentedTimeNano(int)}.
33  */
34 public final class WindowAnimationFrameStats extends FrameStats implements Parcelable {
35     /**
36      * @hide
37      */
WindowAnimationFrameStats()38     public WindowAnimationFrameStats() {
39         /* do nothing */
40     }
41 
42     /**
43      * Initializes this isntance.
44      *
45      * @param refreshPeriodNano The display refresh period.
46      * @param framesPresentedTimeNano The presented frame times.
47      *
48      * @hide
49      */
init(long refreshPeriodNano, long[] framesPresentedTimeNano)50     public void init(long refreshPeriodNano, long[] framesPresentedTimeNano) {
51         mRefreshPeriodNano = refreshPeriodNano;
52         mFramesPresentedTimeNano = framesPresentedTimeNano;
53     }
54 
WindowAnimationFrameStats(Parcel parcel)55     private WindowAnimationFrameStats(Parcel parcel) {
56         mRefreshPeriodNano = parcel.readLong();
57         mFramesPresentedTimeNano = parcel.createLongArray();
58     }
59 
60     @Override
describeContents()61     public int describeContents() {
62         return 0;
63     }
64 
65     @Override
writeToParcel(Parcel parcel, int flags)66     public void writeToParcel(Parcel parcel, int flags) {
67         parcel.writeLong(mRefreshPeriodNano);
68         parcel.writeLongArray(mFramesPresentedTimeNano);
69     }
70 
71     @Override
toString()72     public String toString() {
73         StringBuilder builder = new StringBuilder();
74         builder.append("WindowAnimationFrameStats[");
75         builder.append("frameCount:" + getFrameCount());
76         builder.append(", fromTimeNano:" + getStartTimeNano());
77         builder.append(", toTimeNano:" + getEndTimeNano());
78         builder.append(']');
79         return builder.toString();
80     }
81 
82     public static final Creator<WindowAnimationFrameStats> CREATOR =
83             new Creator<WindowAnimationFrameStats>() {
84                 @Override
85                 public WindowAnimationFrameStats createFromParcel(Parcel parcel) {
86                     return new WindowAnimationFrameStats(parcel);
87                 }
88 
89                 @Override
90                 public WindowAnimationFrameStats[] newArray(int size) {
91                     return new WindowAnimationFrameStats[size];
92                 }
93             };
94 }
95