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.
What would be the best way to do this?
You can find some examples of this here, here (code is taken here), and here.
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];
}
};
}
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"));
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");
This example shows only String
types. But, you can parcel any kind of data you want. Try it out.
EDIT: Another example, suggested by Rukmal Dias.