How to pass ArrayList of Objects from one to anoth

Question

I have the following in code in my onClick() method as

 List<Question> mQuestionsList = QuestionBank.getQuestions();

Now I have the intent after this line, as follows :

  Intent resultIntent = new Intent(this, ResultActivity.class);
  resultIntent.putParcelableArrayListExtra("QuestionsExtra", (ArrayList<? extends Parcelable>) mQuestionsList);
  startActivity(resultIntent);

I don't know how to pass this question lists in the intent from one activity to another activity My Question class

public class Question {
    private int[] operands;
    private int[] choices;
    private int userAnswerIndex;

    public Question(int[] operands, int[] choices) {
        this.operands = operands;
        this.choices = choices;
        this.userAnswerIndex = -1;
    }

    public int[] getChoices() {
        return choices;
    }

    public void setChoices(int[] choices) {
        this.choices = choices;
    }

    public int[] getOperands() {
        return operands;
    }

    public void setOperands(int[] operands) {
        this.operands = operands;
    }

    public int getUserAnswerIndex() {
        return userAnswerIndex;
    }

    public void setUserAnswerIndex(int userAnswerIndex) {
        this.userAnswerIndex = userAnswerIndex;
    }

    public int getAnswer() {
        int answer = 0;
        for (int operand : operands) {
            answer += operand;
        }
        return answer;
    }

    public boolean isCorrect() {
        return getAnswer() == choices[this.userAnswerIndex];
    }

    public boolean hasAnswered() {
        return userAnswerIndex != -1;
    }

    @Override
    public String toString() {
        StringBuilder builder = new StringBuilder();

        // Question
        builder.append("Question: ");
        for(int operand : operands) {
            builder.append(String.format("%d ", operand));
        }
        builder.append(System.getProperty("line.separator"));

        // Choices
        int answer = getAnswer();
        for (int choice : choices) {
            if (choice == answer) {
                builder.append(String.format("%d (A) ", choice));
            } else {
                builder.append(String.format("%d ", choice));
            }
        }
        return builder.toString();
       }

      }

Answer 1

To set the data in kotlin

val offerIds = ArrayList<Offer>()
offerIds.add(Offer(1))
retrunIntent.putExtra(C.OFFER_IDS, offerIds)

To get the data

 val offerIds = data.getSerializableExtra(C.OFFER_IDS) as ArrayList<Offer>?

Now access the arraylist

Answer 2

You can use parcelable for object passing which is more efficient than Serializable .

Kindly refer the link which i am share contains complete parcelable sample. Click download ParcelableSample.zip

Answer 3

It works well,

public class Question implements Serializable {
    private int[] operands;
    private int[] choices;
    private int userAnswerIndex;

   public Question(int[] operands, int[] choices) {
       this.operands = operands;
       this.choices = choices;
       this.userAnswerIndex = -1;
   }

   public int[] getChoices() {
       return choices;
   }

   public void setChoices(int[] choices) {
       this.choices = choices;
   }

   public int[] getOperands() {
       return operands;
   }

   public void setOperands(int[] operands) {
       this.operands = operands;
   }

   public int getUserAnswerIndex() {
       return userAnswerIndex;
   }

   public void setUserAnswerIndex(int userAnswerIndex) {
       this.userAnswerIndex = userAnswerIndex;
   }

   public int getAnswer() {
       int answer = 0;
       for (int operand : operands) {
           answer += operand;
       }
       return answer;
   }

   public boolean isCorrect() {
       return getAnswer() == choices[this.userAnswerIndex];
   }

   public boolean hasAnswered() {
       return userAnswerIndex != -1;
   }

   @Override
   public String toString() {
       StringBuilder builder = new StringBuilder();

       // Question
       builder.append("Question: ");
       for(int operand : operands) {
           builder.append(String.format("%d ", operand));
       }
       builder.append(System.getProperty("line.separator"));

       // Choices
       int answer = getAnswer();
       for (int choice : choices) {
           if (choice == answer) {
               builder.append(String.format("%d (A) ", choice));
           } else {
               builder.append(String.format("%d ", choice));
           }
       }
       return builder.toString();
     }
  }

In your Source Activity, use this :

  List<Question> mQuestionList = new ArrayList<Question>;
  mQuestionsList = QuestionBank.getQuestions();
  mQuestionList.add(new Question(ops1, choices1));

  Intent intent = new Intent(SourceActivity.this, TargetActivity.class);
  intent.putExtra("QuestionListExtra", ArrayList<Question>mQuestionList);

In your Target Activity, use this :

  List<Question> questions = new ArrayList<Question>();
  questions = (ArrayList<Question>)getIntent().getSerializableExtra("QuestionListExtra");

Answer 4

I had the exact same question and while still hassling with the Parcelable, I found out that the static variables are not such a bad idea for the task.

You can simply create a

public static ArrayList<Parliament> myObjects = .. 

and use it from elsewhere via MyRefActivity.myObjects

I was not sure about what public static variables imply in the context of an application with activities. If you also have doubts about either this or on performance aspects of this approach, refer to:

• What's the best way to share data between activities?
• Using static variables in Android

Cheers.

Answer 5

Your arrayList:

ArrayList<String> yourArray = new ArrayList<>();

Write this code from where you want intent:

Intent newIntent = new Intent(this, NextActivity.class);
newIntent.putExtra("name",yourArray);
startActivity(newIntent);

In Next Activity:

ArrayList<String> myArray = new ArrayList<>();

Write this code in onCreate:

myArray =(ArrayList<String>)getIntent().getSerializableExtra("name");

Answer 6

Simple as that !! worked for me

From activity

        Intent intent = new Intent(Viewhirings.this, Informaall.class);
        intent.putStringArrayListExtra("list",nselectedfromadapter);

        startActivity(intent);

TO activity

Bundle bundle = getIntent().getExtras();
    nselectedfromadapter= bundle.getStringArrayList("list");