Question

要将对象的数组列表传递给片段，我必须使列表对象可以使用。

public mObjectClass implements Parcelable {

    // Some code

}

问题是我的列表对象中的一个属性是另一个基于对象的arrayList。

public mObjectClass implements Parcelable {

        // Some code

        private ArrayList<someOtherObject> anotherArrayList;

    }

如何使mObjectClass变得可分割？

Answer 1

someOtherObject必须实施Parcelable（在您的问题中不会扩展）。然后，您可以调用parcel.writeTypedList(anotherArrayList);来编写它，然后parcel.readTypedList(yourList, someOtherObject.CREATOR)将其读回来。您可以阅读更多here

Answer 2

此解决方案受到一些Stackoverflow帖子的严重影响，包括 this

基本上使两个类都可以使用parcelable.Creator。

mObjectClass：

public class mObjectClass implements Parcelable {

    private ArrayList<someOtherObject> anotherArrayList;

    //add getter + setter...

    public mObjectClass() {
        anotherArrayList = new ArrayList<someOtherObject>();
    }

    public mObjectClass(Parcel in) {

        anotherArrayList = new ArrayList<someOtherObject>();
        in.readTypedList(anotherArrayList, someOtherObject.CREATOR);
    }

    public int describeContents() {
        return 0;
    }

    @Override
    public void writeToParcel(Parcel outParcel, int flags) {

        outParcel.writeTypedList(anotherArrayList);
    }

    public static final Parcelable.Creator<MyParcelable> CREATOR = new Parcelable.Creator<MyParcelable>() {

        @Override
        public mObjectClass createFromParcel(Parcel in) {
            return new mObjectClass(in);
        }

        @Override
        public mObjectClass[] newArray(int size) {
            return new mObjectClass[size];
        }
    };
}

someOtherObject：

public class someOtherObject implements Parcelable {
    String someString;

    //add getter + setter...

    public void writeToParcel(Parcel out, int flags) {

        out.writeString(someString);

    }

    public static final Parcelable.Creator<someOtherObject> CREATOR = new Parcelable.Creator<someOtherObject>() {
        public someOtherObject createFromParcel(Parcel in) {
            return new someOtherObject(in);
        }

        public someOtherObject[] newArray(int size) {
            return new someOtherObject[size];
        }
    };

    public int describeContents() {
        return 0;
    }

    public someOtherObject(Parcel in) {
        someString = in.readString();

    }

    public someOtherObject() {
    }

    public someOtherObject(String someString) {
        this.someString = someString;
    }
}

Tada，您现在可以在初始化之后添加mObjectClass作为额外内容，并使用setter将Arraylist与其他someOtherObjects一起设置。

如何使嵌套的ArrayLists可分割

2 个答案: