I have two activities, one is UserActivity and other one is CartActivity I am showing a list of products in UserActivity. On click of a button AddtoCart I am adding the products to the cart. I am facing this problem:
When I add click the button AddtoCart there is a cart icon in the action bar and I have a custom layout of a textview showing cart counter on that cart icon. That counter updates whenever I click the button AddtoCart. Now I move on to the CartActivity and delete some of the products from the cart. When I press back button now to return to UserActivity, the counter text view doesn't update.
I have read about few ways of doing the updation on pressing of back as given in the question here Back button and refreshing previous activity. Two methods given in the answer are by overriding the OnResume() method of UserActivity or by starting activity for result.
I think I need to pass a variable called DeleteCounter from CartActivity to the UserActivity when I press the back button and subtract it from the original number of products in the Counter TextView and update the text view.
Here is the partial code of UserActivity and I have the function to update cart counter in this code only which is called when I click a button. Also the code of onActivityResult() in commented in this which I tried from the answer of above given SO question link. It's not working out:
public class UserActivity extends AppCompatActivity{
private int cartindex = 0;
private TextView counterTV = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_user);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
}
// @Override
// protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// if (requestCode == 1) {
//
// if(resultCode == RESULT_OK){
// Intent intent = getIntent();
// Integer deletecounter = intent.getIntExtra("DeleteCounter",0);
// if(deletecounter>0){
// UpdateCartCount(Integer.parseInt(counterTV.getText().toString())-deletecounter);
// }
// }
// }
// }
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.user, menu);
final View menu_list = menu.findItem(R.id.action_hawk).getActionView();
counterTV = (TextView) menu_list.findViewById(R.id.cartcounter);
UpdateCartCount(cartindex);
new MyMenuItemStuffListener(menu_hotlist, "Show message") {
@Override
public void onClick(View v) {
Intent intent= new Intent(UserActivity.this,CartActivity.class);
intent.putExtra("ProductTitle",pname);
intent.putExtra("ProductUrl",purl);
intent.putExtra("ProductPrice",pprice);
intent.putExtra("BargainPrice",bargainprice);
UserActivity.this.startActivity(intent);
}
};
return true;
}
//Function to update cart count
public void UpdateCartCount(final int new_number) {
cartindex = new_number;
if (counterTV == null) return;
runOnUiThread(new Runnable() {
@Override
public void run() {
if (new_number == 0)
counterTV.setVisibility(View.INVISIBLE);
else {
counterTV.setVisibility(View.VISIBLE);
counterTV.setText(Integer.toString(new_number));
}
}
});
}
Here is the code of CartActivity:
public class CartActivity extends AppCompatActivity {
private List<Product> mCartList;
private ProductAdapter mProductAdapter;
private static List<Product> cart;
private static Integer deletecounter= 0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_cart);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
mCartList = getCart();
Intent intent = getIntent();
String ProductTitle = intent.getStringExtra("ProductTitle");
String ProductUrl = intent.getStringExtra("ProductUrl");
String ProductPrice = intent.getStringExtra("ProductPrice");
String BargainPrice = intent.getStringExtra("BargainPrice");
Product product = new Product(ProductTitle, ProductUrl, ProductPrice, BargainPrice);
mCartList.add(product);
// Make sure to clear the selections
for (int i = 0; i < mCartList.size(); i++) {
mCartList.get(i).selected = false;
}
// Create the list
final ListView listViewCatalog = (ListView) findViewById(R.id.cart_list_view);
mProductAdapter = new ProductAdapter(mCartList, getLayoutInflater(), true, CartActivity.this);
listViewCatalog.setAdapter(mProductAdapter);
listViewCatalog.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position,
long id) {
Product selectedProduct = mCartList.get(position);
if (selectedProduct.selected)
selectedProduct.selected = false;
else
selectedProduct.selected = true;
mProductAdapter.notifyDataSetInvalidated();
}
});
FloatingActionButton Delete = (FloatingActionButton) findViewById(R.id.fab);
delete.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
// Loop through and remove all the products that are selected
// Loop backwards so that the remove works correctly
for (int i = mCartList.size() - 1; i >= 0; i--) {
if (mCartList.get(i).selected) {
mCartList.remove(i);
deletecounter++;
}
}
// THIS IS THE CODE I USED TO RETURN DATA TO PREVIOUS ACTIVITY BUT UserActivity STARTS AUTOMATICALLY AFTER DELETION OF SELECTED PRODUCTS AS SOON AS I CLICK THE DELETE BUTTON EVEN WHEN THERE ARE PRODUCTS IN THE CART.
// if(deletecounter!=0) {
// Intent i = new Intent(HawkActivity.this, UserActivity.class);
// startActivityForResult(i, 1);
// Intent returnIntent = new Intent();
// returnIntent.putExtra("DeleteCounter", deletecounter);
// setResult(RESULT_OK, returnIntent);
// }
mProductAdapter.notifyDataSetChanged();
Snackbar.make(view,"Selected items deleted successfully",Snackbar.LENGTH_SHORT).show();
}
}
);
}
public static List<Product> getCart() {
if(cart == null) {
cart = new Vector<Product>();
}
return cart;
}
}
When I use the code which is commented out in both the activities i.e use of start activity for result method, this happens:
When I click on the delete button, items get deleted but the CartActivity closes automatically. The UserActivity with counter text view is shown having '0' value even when there are products in the cart.
Do tell me about any other info you need from the code. Any other ways I can implement to update the cart counter on pressing of back button after deletion of some items in CartActivity are welcome. Any help is appreciated.
CartActivityfinishes itself, even when products are still there in the cart and theUserActivityappears with zero counter in the cart. I don't wantUserActivityto appear at all when I click delete! If I press back than it should appear with the updated count of the cart. – Salomo