Writing Objects members to Parcels

Question

So far I've been chugging along with Parcelable objects without issue, mainly because all of their members have been types that have writeX() methods associated with them. For example, I do:

public String name;

private Foo(final Parcel in) {
    name = in.readString(); }
public void writeToParcel(final Parcel dest, final int flags) {
    dest.writeString(name); }

But now if I have a Bar member things get a little dicey for me:

public Bar bar;

private Foo(final Parcel in) {
    bar = new Bar(); //or i could actually write some constructor for Bar, this is a demo.
    bar.memberString = in.readString();
}

public void writeToParcel(final Parcel dest, final int flags) {
    // What do I do here?
}

Am I approaching this the wrong way? What should I do in my writeToParcel to parcel member Bars?

score 30 · Accepted Answer · answered Mar 28 '12 at 21:24

30

The correct and more OO way is make Bar implements Parcelable too.

To read Bar in your private Foo constructor:

private Foo(final Parcel in) {
  ... ...
  bar = in.readParcelable(getClass().getClassLoader());
  ... ...
}

To write Bar in your writeToParcel method:

public void writeToParcel(final Parcel dest, final int flags) {
  ... ...
  dest.writeParcelable(bar, flags);
  ... ...
}

Hope this helps.

answered Mar 28 '12 at 21:24

yorkw

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5

adding because some might get confuse here **getClass().getClassLoader()** means **Bar.class.getClassLoader()** – Junaid Oct 12 '16 at 17:22
What should I do if my class is provided by the SDK and cannot be modified? – Eido95 Nov 15 '16 at 20:10

score 0 · Answer 2 · answered Mar 28 '12 at 22:21

0

Parceables are a pain and only pass by value and not reference. I would never recommend using them. Make a static model instance if you application and just get a shim reference to the object you need.

answered Mar 28 '12 at 22:21

user123321

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Using singletons as a design principle is flawed in object oriented programming. Deserialize into json or store the values, do not have a global class all your other classes can access. – HarshMarshmallow Jul 13 '16 at 17:05

Writing Objects members to Parcels

2 Answers2