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I am trying to pass an arrayList to another activity using intents. Here is the code in the first activity.

case R.id.editButton:
        Toast.makeText(this, "edit was clicked", Toast.LENGTH_LONG).show();
        Intent intent = new Intent(this, editList.class);
        intent.putStringArrayListExtra("stock_list", stock_list);
        startActivity(intent);
        break;
This is where I try to retrieve the list in the second activity. Is something wrong here?
Intent i = new Intent(); //This should be getIntent();
    stock_list = new ArrayList<String>();
    stock_list = i.getStringArrayListExtra("stock_list");
The way you have it you've just created a new empty intent without any extras.
If you only have a single extra you can condense this down to:
stock_list = getIntent().getStringArrayListExtra("stock_list");
Add compile 'com.google.code.gson:gson:2.2.4' in dependencies block build.gradle. 
Click on Sync Project with Gradle Files
Cars.java:
public class Cars {
    public String id, name;
FirstActivity.java
When you want to pass ArrayList:
List<Cars> cars= new ArrayList<Cars>();
cars.add(getCarModel("1", "A"));
cars.add(getCarModel("2", "B"));
cars.add(getCarModel("3", "C"));
cars.add(getCarModel("4", "D"));
Gson gson = new Gson();
String jsonCars = gson.toJson(cars);
Intent intent = new Intent(FirstActivity.this, SecondActivity.class);
intent.putExtra("list_as_string", jsonCars);
startActivity(intent);
Get CarsModel by Function:
private Cars getCarModel(String id, String name){
       Cars cars = new Cars();
       cars.id = id;
       cars.name = name;
    return cars;
SecondActivity.java
You have to import java.lang.reflect.Type ;
on onCreate() to retrieve ArrayList:
String carListAsString = getIntent().getStringExtra("list_as_string");
Gson gson = new Gson();
Type type = new TypeToken<List<Cars>>(){}.getType();
List<Cars> carsList = gson.fromJson(carListAsString, type);
for (Cars cars : carsList){
   Log.i("Car Data", cars.id+"-"+cars.name);
Hope this will save time, I saved it.
                Or you can simply have your Cars model class implement Parcelable interface and simply do intent.putParcelableArrayListExtra("parecelable_list", carsList); where carsList is an instance of ArrayList<Cars>
– Nouman Hanif
                Dec 12, 2015 at 19:47
                Why would I use Gson if there is already intent.putStringArrayListExtra, intent.getStringArrayListExtra or getSerializableExtra exists. And what if I use eclipse? I have to download and add Gson library?
– Tushar Monirul
                May 18, 2016 at 18:47
                My 2 bits... You can't down vote this for that reason, but you should recommend Parceling over Serializing as its been proved many times over - for Android its more efficient & out performs Serialization.
– user3833732
                Oct 17, 2019 at 10:48
Receiving Intent Like :
aListModel = (ArrayList<Model>) getIntent().getSerializableExtra(KEY);
MUST REMEMBER:
Here Model-class must be implemented like:
 ModelClass implements Serializable
                Normally like Sending Intent for startActivityForResult:  Intent intent = new Intent(MainActivity.this, SecondActivity.class);   startActivityForResult(intent, aListModel);
– Dhruv Raval
                Sep 4, 2015 at 4:36
Suppose you need to pass an arraylist of following class from current activity to next activity 
// class of the objects those in the arraylist
// remember to implement the class from Serializable interface
// Serializable means it converts the object into stream of bytes and helps to transfer that object
public class Question implements Serializable {
in your current activity you probably have an ArrayList as follows
ArrayList<Question> qsList = new ArrayList<>();
qsList.add(new Question(1));
qsList.add(new Question(2));
qsList.add(new Question(3));
// intialize Bundle instance
Bundle b = new Bundle();
// putting questions list into the bundle .. as key value pair.
// so you can retrieve the arrayList with this key
b.putSerializable("questions", (Serializable) qsList);
Intent i = new Intent(CurrentActivity.this, NextActivity.class);
i.putExtras(b);
startActivity(i);
in order to get the arraylist within the next activity 
//get the bundle
Bundle b = getIntent().getExtras();
//getting the arraylist from the key
ArrayList<Question> q = (ArrayList<Question>) b.getSerializable("questions");
//arraylist/Pojo you can Pass using bundle  like this 
Intent intent = new Intent(MainActivity.this, SecondActivity.class);
Bundle args = new Bundle();
                        args.putSerializable("imageSliders",(Serializable)allStoriesPojo.getImageSliderPojos());
                        intent.putExtra("BUNDLE",args);
 startActivity(intent); 
Get SecondActivity like this
  Intent intent = getIntent();
        Bundle args = intent.getBundleExtra("BUNDLE");
String filter = bundle.getString("imageSliders");
//Happy coding
                It is throwing an exception:  java.lang.ClassCastException: com.example.ModelObjectNameHere cannot be cast to java.io.Serializable
– Ali Tamoor
                Feb 17, 2021 at 7:26
and create a new Intent that put Bundle to Intent
Intent intent=new Intent(ActivityOne.this,ActivityTwo.class);
intent.putExtras(bundle);
startActivity(intent);
for receive bundle insert this code
Bundle bundle = getIntent().getExtras();
ArrayList<StructMain> item = (ArrayList<StructMain>) bundle.getSerializable("test");
        
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