如何使自定义对象可拆分? [英] How can I make my custom objects Parcelable?
问题描述
我正在尝试使我的对象可包裹.但是,我有自定义对象,这些对象具有我创建的其他自定义对象的ArrayList
属性.
I'm trying to make my objects Parcelable. However, I have custom objects and those objects have ArrayList
attributes of other custom objects I have made.
做到这一点的最佳方法是什么?
What would be the best way to do this?
推荐答案
您可以找到此此处(此处获取代码)和您可以为此创建一个POJO类,但是您需要添加一些额外的代码以使其成为Parcelable
.看一下实现.
You can create a POJO class for this, but you need to add some extra code to make it Parcelable
. Have a look at the implementation.
public class Student implements Parcelable{
private String id;
private String name;
private String grade;
// Constructor
public Student(String id, String name, String grade){
this.id = id;
this.name = name;
this.grade = grade;
}
// Getter and setter methods
.........
.........
// Parcelling part
public Student(Parcel in){
String[] data = new String[3];
in.readStringArray(data);
// the order needs to be the same as in writeToParcel() method
this.id = data[0];
this.name = data[1];
this.grade = data[2];
}
@Оverride
public int describeContents(){
return 0;
}
@Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeStringArray(new String[] {this.id,
this.name,
this.grade});
}
public static final Parcelable.Creator CREATOR = new Parcelable.Creator() {
public Student createFromParcel(Parcel in) {
return new Student(in);
}
public Student[] newArray(int size) {
return new Student[size];
}
};
}
创建此类后,您可以像这样通过Intent
轻松传递此类的对象,并在目标活动中恢复该对象.
Once you have created this class, you can easily pass objects of this class through the Intent
like this, and recover this object in the target activity.
intent.putExtra("student", new Student("1","Mike","6"));
在这里,学生是您从包裹中拆包数据所需要的钥匙.
Here, the student is the key which you would require to unparcel the data from the bundle.
Bundle data = getIntent().getExtras();
Student student = (Student) data.getParcelable("student");
此示例仅显示String
类型.但是,您可以打包所需的任何类型的数据.试试吧.
This example shows only String
types. But, you can parcel any kind of data you want. Try it out.
另一个示例,由Rukmal Dias .
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