How to pass ArrayList from one acti

问题:

This question already has an answer here:

• Passing arraylist of objects between activities 4 answers

I want to send Following ArrayList from one activity to another please help.

ContactBean m_objUserDetails = new ContactBean();
ArrayList<ContactBean> ContactLis = new ArrayList<ContactBean>(); 

I am sending the above arraylist after adding data in it as follows

  Intent i = new Intent(this,DisplayContact.class);
  i.putExtra(\"Contact_list\", ContactLis);
  startActivity(i);

But I am getting problem while recovering it.

ArrayList<ContactBean> l1 = new ArrayList<ContactBean>();
Bundle wrapedReceivedList = getIntent().getExtras();
l1= wrapedReceivedList.getCharSequenceArrayList(\"Contact_list\");

At this point I am getting this error:

Type mismatch: cannot convert from ArrayList<CharSequence> to ArrayList<ContactBean>

My ContactBean class implements Serializable please also tell why we have to implement serializable interface.

回答1:

You can pass an ArrayList<E> the same way, if the E type is Serializable.

You would call the putExtra (String name, Serializable value) of Intent to store, and getSerializableExtra (String name) for retrieval.

Example:

ArrayList<String> myList = new ArrayList<String>();
intent.putExtra(\"mylist\", myList);

In the other Activity:

ArrayList<String> myList = (ArrayList<String>) getIntent().getSerializableExtra(\"mylist\");

回答2:

In First activity:

ArrayList<ContactBean> fileList = new ArrayList<ContactBean>();
Intent intent = new Intent(MainActivity.this, secondActivity.class);
intent.putExtra(\"FILES_TO_SEND\", fileList);
startActivity(intent);

In receiver activity:

ArrayList<ContactBean> filelist =  (ArrayList<ContactBean>)getIntent().getSerializableExtra(\"FILES_TO_SEND\");`

回答3:

you need implements Parcelable in your ContactBean class, I put one example for you:

public class ContactClass implements Parcelable {

private String id;
private String photo;
private String firstname;
private String lastname;

public ContactClass()
{

}

private ContactClass(Parcel in) {
    firstname = in.readString();
    lastname = in.readString();
    photo = in.readString();
    id = in.readString();

}

@Override
public int describeContents() {
    // TODO Auto-generated method stub
    return 0;
}

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

    dest.writeString(firstname);
    dest.writeString(lastname);
    dest.writeString(photo);
    dest.writeString(id);

}

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

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

        }
    };

   // all get , set method 
 }

and this get and set for your code:

Intent intent = new Intent(this,DisplayContact.class);
intent.putExtra(\"Contact_list\", ContactLis);
startActivity(intent);

second class:

ArrayList<ContactClass> myList = getIntent().getParcelableExtra(\"Contact_list\");

回答4:

Use this code to pass arraylist<customobj> to anthother Activity

firstly serialize our contact bean

public class ContactBean implements Serializable {
      //do intialization here
}

Now pass your arraylist

 Intent intent = new Intent(this,name of activity.class);
 contactBean=(ConactBean)_arraylist.get(position);
 intent.putExtra(\"contactBeanObj\",conactBean);
 _activity.startActivity(intent);