Activity onResume()

Issue

I am writing a Shopping Cart App in which i am allowing user to choose items to buy and add their required items to Cart, for this i have given two different tabs,

First Tab, to browse products

Second Tab, to browse Items in Cart [User Added]

Here I am facing a small problem. I am not getting updated quantity in Cart, but getting changes in total price, whenever i do change in Item Quantity.

So, tell me what I need to add in my code to get changes in Quantity also, How to Update Quantity while moving between Tabs

I have written below code in onResume() under ViewCartActivity.java:

@Override
protected void onResume() 
{
    super.onResume();
    if (Constants.mItem_Detail.size() == 0) 
    {
        return;
    }

    Double mGTotal = Double.parseDouble(Constants.mItem_Detail.get(0).get(SingleTrackActivity.KEY_TOTAL));
    for (int i = 1; i < Constants.mItem_Detail.size(); i++) 
    {   
    mGTotal = mGTotal + Double.parseDouble(Constants.mItem_Detail.get(i).get(SingleTrackActivity.KEY_TOTAL));
    }
    mGrandTotal = String.valueOf(mGTotal);
    mTxtViewGrandTotal.setText(mGrandTotal);
    myTextVeiwGrandTotal.setText(mGrandTotal);
    mTxtViewGrandTotal.setText(new DecimalFormat("##.##").format(mGTotal));
    mTotal = String.valueOf(Constants.mItem_Detail.size());
    mItems.setText(mTotal);
}

Please see below screen shot, i have updated quantity of an item from 1 to 10, therefore i got changes in Total Amount, but did not get any change in Quantity getting 1 only,whenever i am moving between tabs i am facing this problem:

Using Below code in Products.java class to update quantity of an Item:

  for (int i = 0; i < Constants.mItem_Detail.size(); i++) {
                                            if (Constants.mItem_Detail.get(i).get(TAG_NAME)
                                                    .equals(song_name)) {
                                                Constants.mItem_Detail.remove(i);
                                                break;}

Note:

If i will not move to Cart Tab from Products Tab, I am able to view changes in Quantity of an Item, but once i will move to Cart Tab from Products Tab then i am not getting changes in Quantity of an Item...

Solution

I guess you are on right path, just check with patience, add items to cart then update cart items, wait for few seconds, i hope it will update your cart itself.....

Your code looks like good to me:

        for (int i = 0; i < Constants.mItem_Detail.size(); i++) {
        if (Constants.mItem_Detail.get(i).get(TAG_NAME)
        .equals(song_name)) {
        Constants.mItem_Detail.remove(i);
        break;

Answered By - ASMUIRTI