How to pass an object to a new activity in android studio?

Question

I am attempting to pass an object from one activity to another. I have tried using just intent and how with bundle but I am not sure what is wrong. I have looked at similar solutions here and that is where I got most of my code for this, but it seems that my copy and paste does not work.

This is my main class

    public class MainActivity extends AppCompatActivity {
    Item item;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        createNewItem();

        Button buttonOne = findViewById(R.id.itemButton);
        buttonOne.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                Intent intent = new Intent(getApplicationContext(), ViewItemDetails.class);
                Bundle bundle = new Bundle();
                bundle.putSerializable("item", item);
                intent.putExtras(bundle);
                startActivity(intent);

            }
        });

    }

    void createNewItem(){
        item=new Item("Pixel 4","https://google.com",1000.00);
    }
}

This is the activity I am trying to go to:

    public class ViewItemDetails extends AppCompatActivity {

    Intent intent= getIntent();
    Bundle bundle= intent.getExtras();
    Item item = (Item) bundle.getSerializable("item");

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_view_item_details);
        setStrings();
        setButtons();
    }
    void setStrings() {
        try {
            TextView nameTextView = findViewById(R.id.itemNameid);
            nameTextView.setText(item.getItemName());

            TextView itemInitTV = findViewById(R.id.initalPriceNumID);
            itemInitTV.setText(Double.toString(item.getInitPrice()));

            TextView itemCurrTV = findViewById(R.id.currentPriceNumid);
            itemCurrTV.setText(Double.toString(item.getCurrentPrice()));
        }catch (NullPointerException e){
            //do noting
        }
    }

    void setButtons(){
        Button buyButton = findViewById(R.id.buyButtonid);
        buyButton.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                Uri uriUrl = Uri.parse(item.getWebaddress());
                Intent launchBrowser = new Intent(Intent.ACTION_VIEW, uriUrl);
                startActivity(launchBrowser);
            }
        });

        Button refreshButton= findViewById(R.id.refrechId);
        refreshButton.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                Double newPrice= new GenerateNewPrice().GenerateNewPrice(item.getWebaddress());
                Toast toast = Toast.makeText(getApplicationContext(),Double.toString(newPrice), Toast.LENGTH_SHORT);
                toast.show();
            }
        });

        Button editButton= findViewById(R.id.editid);
        editButton.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {

                Toast toast = Toast.makeText(getApplicationContext(),"Attempt to edit", Toast.LENGTH_SHORT);
                toast.show();
            }
        });

    }
}

This is the object I am attempting to pass between activities.

    public class Item implements Serializable {
    String itemName, webaddress;
    Double initPrice, CurrentPrice;

    public Item(String itemName, String webaddress, Double initPrice) {
        this.itemName = itemName;
        this.webaddress = webaddress;
        this.initPrice = initPrice;
    }

    public String getItemName() {
        return itemName;
    }

    public String getWebaddress() {
        return webaddress;
    }

    public Double getInitPrice() {
        return initPrice;
    }

    public Double getCurrentPrice() {
        return CurrentPrice;
    }
 }

When I run the app on my phone I click the button and then the app closes.

Thank you for your help. If needed I can add more code. I have seen similar questions here, but they have not worked for me. I got similar code from those posts but have not solved my solution. I appreciate any feedback that is give. Thank you for your time.

Possible duplicate of [How do I pass data between Activities in Android application?](https://stackoverflow.com/questions/2091465/how-do-i-pass-data-between-activities-in-android-application) — shizhen, Oct 14 '19 at 03:49
Also, see: https://stackoverflow.com/questions/2736389/how-to-pass-an-object-from-one-activity-to-another-on-android — shizhen, Oct 14 '19 at 03:49

score 1 · Accepted Answer · answered Oct 14 '19 at 04:25

For now and for future help on SOF, remember, Error logs are always helpful in that kind of scenario.

Though, Here are some points..

You should follow the Activity lifecycle rule, Getting the data in onCreate() will be a good idea.
You should use Parcelable instead of Serializable. It is much more efficient.

score 1 · Answer 2 · answered Oct 14 '19 at 06:10

1

your initialisation of bundle and item is wrong in the ViewItemDetails.java activity. Try to initialise inside the onCreate method and let us know..

answered Oct 14 '19 at 06:10

Peer Mohamed

408
4
15

score 0 · Answer 3 · answered Oct 14 '19 at 04:51

Seems like you have some bug, it should work, you can check out one of the project work example //creating the budle

 listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
            //String selectedItem = (String) adapterView.getItemAtPosition(i);
            //getting dat from text view and converting to string
           // String textview =((TextView)view.findViewById(R.id.textViewName)).getText().toString();
            //Toast.makeText(DriverInfo.this,"Driver id "+driver_id,Toast.LENGTH_SHORT).show();
            Bundle bundle=new Bundle();
            bundle.putString("DriverID",driver_id);
            bundle.putString("Route",loc_src);
            bundle.putString("Dest",loc_dest);
            bundle.putString("location_address",location_address);
            Toast.makeText(DriverInfo.this, "Driver ID="+driver_id, Toast.LENGTH_SHORT).show();
            Intent intent=new Intent(DriverInfo.this, DirverCurrentLoc.class);
            intent.putExtras(bundle);
            startActivity(intent);

        }
    });

//Getting the bundle data

 String lat, lng, realtime,src,dest;
     location_address=intent.getStringExtra("location_address");
        driver_id=intent.getStringExtra("DriverID");
        src=intent.getStringExtra("Route");
        dest=intent.getStringExtra("Dest");

score 0 · Answer 4 · answered Oct 14 '19 at 04:57

0

You have to initialize this code in onCreate() method like below :

Item item;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_view_item_details);

Intent intent= getIntent();
Bundle bundle= intent.getExtras();
item = (Item) bundle.getSerializable("item");

setStrings();
setButtons();

}

answered Oct 14 '19 at 04:57

Faisal Ahmed

816
9
12

Welcome @AndreaTorres – Faisal Ahmed Oct 14 '19 at 06:42

score 0 · Answer 5 · answered Oct 14 '19 at 06:43

You can use GSON to convert your Object into a JSON format

Intent intent = new Intent(this, ProjectActivity.class);
intent.putExtra("item", new Gson().toJson(item));
startActivity(intent);

then in your second activity, make sure you initialize the bundle correctly in onCreate() lifecycle.

Item item;

@Override
protected void onCreate(Bundle savedInstanceState) {
    .........
    Bundle extras = getIntent().getExtras();
    if (extras != null) {
        item = new Gson().fromJson(extras.getString("item"), Item.class);
    }

Note: I read this in an article that google recommends GSON when passing objects on bundle.

How to pass an object to a new activity in android studio?

5 Answers5