Android中Parcelable接口的使用

 1 public interface Parcelable {
 2     //内容描述接口，基本不用管
 3     public int describeContents();
 4     //写入接口函数，打包
 5     public void writeToParcel(Parcel dest, int flags);
 6      //读取接口，目的是要从Parcel中构造一个实现了Parcelable的类的实例处理。因为实现类在这里还是不可知的，所以需要用到模板的方式，继承类名通过模板参数传入。
 7     //为了能够实现模板参数的传入，这里定义Creator嵌入接口,内含两个接口函数分别返回单个和多个继承类实例。
 8     public interface Creator<T> {
 9            public T createFromParcel(Parcel source);
10            public T[] newArray(int size);
11        }

 1 public class AppContent implements Serializable, Parcelable {
 2     //应用名字
 3     private String name;
 4     //应用下载链接
 5     private String url;
 6 
 7     private int downloadPercent = 0;
 8 
 9     private Status status = Status.PENDING;
10 
11     public AppContent(String name, String url) {
12         this.name = name;
13         this.url = url;
14     }
15 
16     public String getName() {
17         return name;
18     }
19 
20     public void setName(String name) {
21         this.name = name;
22     }
23 
24     public String getUrl() {
25         return url;
26     }
27 
28     public void setUrl(String url) {
29         this.url = url;
30     }
31 
32     public int getDownloadPercent() {
33         return downloadPercent;
34     }
35 
36     public void setDownloadPercent(int downloadPercent) {
37         this.downloadPercent = downloadPercent;
38     }
39 
40     public Status getStatus() {
41         return status;
42     }
43 
44     public void setStatus(Status status) {
45         this.status = status;
46     }
47 
48     @Override
49     public String toString() {
50         return name;
51     }
52 
53     @Override
54     public int describeContents() {
55         return 0;
56     }
57 
58     //实现Parcel接口必须覆盖实现的方法
59     @Override
60     public void writeToParcel(Parcel dest, int flags) {
61         /*将AppContent的成员写入Parcel，
62          * 注：Parcel中的数据是按顺序写入和读取的，即先被写入的就会先被读取出来
63          */
64         dest.writeString(name);
65         dest.writeString(url);
66         dest.writeInt(downloadPercent);
67         dest.writeValue(status);
68     }
69 
70     //该静态域是必须要有的，而且名字必须是CREATOR，否则会出错
71     public static final Parcelable.Creator<AppContent> CREATOR =
72             new Parcelable.Creator<AppContent>() {
73 
74                 @Override
75                 public AppContent createFromParcel(Parcel source) {
76                     //从Parcel读取通过writeToParcel方法写入的AppContent的相关成员信息
77                     String name = source.readString();
78                     String url = source.readString();
79                     int downloadPercent = source.readInt();
80                     Status status = (Status)source.readValue(new ClassLoader(){});
81                     AppContent appContent = new AppContent(name, url);
82                     appContent.setDownloadPercent(downloadPercent);
83                     appContent.setStatus(status);
84                     //更加读取到的信息，创建返回Person对象
85                     return appContent;
86                 }
87 
88                 @Override
89                 public AppContent[] newArray(int size)
90                 {
91                     // TODO Auto-generated method stub
92                     //返回AppContent对象数组
93                     return new AppContent[size];
94                 }
95             };
96 
97 }

1    Intent intent = new Intent(Constants.DOWNLOAD_MSG);
2    Bundle bundle = new Bundle();
3    bundle.putParcelable("appContent", appContent);
4    intent.putExtras(bundle);