滚动列表视图时 TextView 的值发生了变化 [英] TextView's value changed while scrolling listview

问题描述

我正在使用列表视图来填充数据.在滚动它之前一切都很好.滚动时，所有 textview (COUNT) 都更改为默认值.这里我使用 Cursor 适配器来填充它.

I am using listview to populate data.Everything is fine until scroll it. While scrolling all the textview (COUNT) is changed to default value. Here I am using Cursor adapter to populate it.

当我在一个项目中点击 ^/向下箭头 时，下一个项目的值会发生变化.

When I clicked ^ / Down arrow in a item the next items value is changed.

下一个错误:

当我点击REMOVE按钮时，不是删除我点击的项目，而是从列表中删除其他项目.

When I click REMOVE Button, instead of remove the item which I clicked,other item is removed from the list.

这是我的 AdapterClass:

Here is my AdapterClass:

public class CartCursorAdapter extends CursorAdapter implements View.OnClickListener {

    public static final String MyPREFERENCES = "Preference";
    public ViewHolder viewHolder;
    DbUtil dbUtil;
    LayoutInflater mInflater;
    Context contextNew;
    String MY_FRAGEMNT;
    SharedPreferences pref;
    String strItemName, strCategoryName, strPrice, strCartCount;
    int price = 0;
    String quantity;
    int total;
    String netA = "0";
    int sum = 0;
    float netAmount;
    int cartPrice, cartSum, cartCount;

    public CartCursorAdapter(Context context, Cursor c, String MYFRAGMENT, boolean autoRequery) {
        super(context, c, autoRequery);
        mInflater = LayoutInflater.from(context);
        contextNew = context;
        MY_FRAGEMNT = MYFRAGMENT;
        dbUtil = new DbUtil(context);
        dbUtil.open();
        pref = context.getSharedPreferences(MyPREFERENCES, Context.MODE_PRIVATE);
        strItemName = pref.getString("itemName", null);
        strCategoryName = pref.getString("categoryName", null);
        strPrice = pref.getString("Price", null);
        strCartCount = pref.getString("cartCount", null);
    }

    @Override
    public View newView(Context context, Cursor cursor, ViewGroup parent) {
        View v = mInflater.inflate(R.layout.cart_list_item, null);
        return v;
    }

    @Override
    public void bindView(View itemView, Context context, Cursor cursor) {
        viewHolder = (ViewHolder) itemView.getTag();
        if (viewHolder == null) {

            viewHolder = new ViewHolder();
            viewHolder.cartProduct = (TextView) itemView.findViewById(R.id.cartProduct);
            viewHolder.cartQuantity = (TextView) itemView.findViewById(R.id.cartQuantity);
            viewHolder.cartPrice = (TextView) itemView.findViewById(R.id.cartPrice);
            viewHolder.cartPriceDum = (TextView) itemView.findViewById(R.id.cartPriceDum);
            viewHolder.cartCount = (TextView) itemView.findViewById(R.id.cartCount);
            viewHolder.ivDecrease = (ImageView) itemView.findViewById(R.id.ivDecrease);
            viewHolder.ivIncrease = (ImageView) itemView.findViewById(R.id.ivIncrease);
            viewHolder.addTowish = (Button) itemView.findViewById(R.id.addTowish);
            viewHolder.remove = (Button) itemView.findViewById(R.id.remove);
            viewHolder.cardView = (CardView) itemView.findViewById(R.id.cardlist_item);
            viewHolder.ivDecrease.setOnClickListener(this);
            viewHolder.ivIncrease.setOnClickListener(this);
            viewHolder.addTowish.setOnClickListener(this);
            viewHolder.remove.setOnClickListener(this);
            itemView.setTag(viewHolder);

        }

        if (MY_FRAGEMNT == "CheckOutFragment") {
            viewHolder.addTowish = (Button) itemView.findViewById(R.id.addTowish);
            viewHolder.remove = (Button) itemView.findViewById(R.id.remove);
            viewHolder.addTowish.setVisibility(View.GONE);
            viewHolder.remove.setVisibility(View.GONE);
            viewHolder.cardView.setCardElevation(0);
            LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams
                    (LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT);
            viewHolder.cardView.setLayoutParams(layoutParams);
            itemView.setTag(viewHolder);
        }

        String pdtName = cursor.getString(cursor.getColumnIndex(DbHelper.CART_PDT_NAME));
        String catName = cursor.getString(cursor.getColumnIndex(DbHelper.CART_CAT_NAME));
        int cartprice = cursor.getInt(cursor.getColumnIndex(DbHelper.CART_PRICE));
        int strquantity = cursor.getInt(cursor.getColumnIndex(DbHelper.CART_QUANTITY));
        viewHolder.cartProduct.setText(pdtName);
        viewHolder.cartPrice.setText(String.valueOf(cartprice));
        viewHolder.cartQuantity.setText(catName);
        viewHolder.cartCount.setText(String.valueOf(strquantity));
    }

    @Override
    public void onClick(View view) {
        switch (view.getId()) {
            case R.id.remove:
                dbUtil.open();
                String delItem = viewHolder.cartProduct.getText().toString();
                Cursor Cartcursor = dbUtil.getCartID(delItem);
                if (Cartcursor != null && Cartcursor.moveToFirst()) {
                    Cartcursor.moveToFirst();
                    String strCartProductID = Cartcursor.getString(Cartcursor.getColumnIndex(DbHelper.CART_PDT_ID));
                    dbUtil.deleteCart(strCartProductID, delItem);
                    Toast.makeText(contextNew, "Cart Item " + "RowId" + strCartProductID + " Product Id" + delItem, Toast.LENGTH_SHORT).show();
                    Toast.makeText(contextNew, "Deleted Successfully", Toast.LENGTH_SHORT).show();
                }
                break;

            case R.id.addTowish:
                break;
            case R.id.ivIncrease:
                increase();
                break;
            case R.id.ivDecrease:
                decrease();
                break;

        }
    }

    private void decrease() {
        strPrice = viewHolder.cartPrice.getText().toString();
        price = Integer.parseInt(strPrice);
        int counter = 0;
        try {
            counter = Integer.parseInt(viewHolder.cartProduct.getText().toString());
        } catch (NumberFormatException e) {
            e.printStackTrace();
        }
        counter--;

        if (counter > 0) {
            viewHolder.cartProduct.setText(Integer.toString(counter));
            viewHolder.cartPrice.setVisibility(View.GONE);
            viewHolder.cartPriceDum.setVisibility(View.VISIBLE);
            quantity = viewHolder.cartProduct.getText().toString();
            total = (Integer.parseInt(quantity)) * (price);
            netA = String.valueOf(total);
            sum -= price;
            netAmount = sum;

            viewHolder.cartPriceDum.setText(String.valueOf(total));
            cartCount = Integer.parseInt(quantity);
            //                          Toast.makeText(context, "netAmount" + netAmount + "\n" + "Total" + total, Toast.LENGTH_SHORT).show();
            if (counter == 1) {
                cartPrice = price;
                cartSum = sum;
            }

            if (counter == 0) {
                cartPrice = 0;
                cartSum = 0;
                cartCount = 0;
//                Toast.makeText(context, "Minimum Item is 1", Toast.LENGTH_SHORT).show();
            }
        }
    }

    private void increase() {
        strPrice = viewHolder.cartPrice.getText().toString();
        price = Integer.parseInt(strPrice);
        int counter = 0;
        try {
            counter = Integer.parseInt(viewHolder.cartCount.getText().toString());
        } catch (NumberFormatException e) {
            e.printStackTrace();
        }
        counter++;

        if (counter > 0) {
            viewHolder.cartCount.setText(Integer.toString(counter));
            viewHolder.cartPrice.setVisibility(View.GONE);
            viewHolder.cartPriceDum.setVisibility(View.VISIBLE);
            quantity = viewHolder.cartCount.getText().toString();

            total = (Integer.parseInt(quantity)) * (price);
            netA = String.valueOf(total);
            sum += price;
            netAmount = sum;

            viewHolder.cartPriceDum.setText(String.valueOf(total));
            cartCount = Integer.parseInt(quantity);
            //                          Toast.makeText(context, "netAmount" + netAmount + "\n" + "Total" + total, Toast.LENGTH_SHORT).show();
            if (counter == 1) {
                cartPrice = price;
                cartSum = sum;
            }

            if (counter == 0) {
                cartPrice = 0;
                cartSum = 0;
                cartCount = 0;
            }
        }
    }

    public static class ViewHolder {
        public static Button addTowish, remove;
        public TextView cartProduct, cartQuantity, cartPrice, cartCount, cartPriceDum;
        public ImageView ivDecrease, ivIncrease;
        CardView cardView;
    }
}

推荐答案

对于 REMOVE :创建自定义的 OnClickListener，以 carProduct 作为其参数

For REMOVE : Create custom OnClickListener which takes cartProduct as its parameter

 public class CustomOnClick implements OnClickListener {
    String product;


    public CustomOnClick(String product) {
        super();
        this.product = product;
    }

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub
        dbUtil.open();
            String delItem = product; //set product to delItem
            Cursor Cartcursor = dbUtil.getCartID(delItem);
            if (Cartcursor != null && Cartcursor.moveToFirst()) {
                Cartcursor.moveToFirst();
                String strCartProductID = Cartcursor.getString(Cartcursor.getColumnIndex(DbHelper.CART_PDT_ID));
                dbUtil.deleteCart(strCartProductID, delItem);
                Toast.makeText(contextNew, "Cart Item " + "RowId" + strCartProductID + " Product Id" + delItem, Toast.LENGTH_SHORT).show();
                Toast.makeText(contextNew, "Deleted Successfully", Toast.LENGTH_SHORT).show();
            }
    }
}

然后在设置 onclicklistener 以删除按钮时，您可以尝试

then while setting onclicklistener to remove button you can try

  viewHolder.remove.setOnClickListener(new CustomOnClick(cursor.getString(cursor.getColumnIndex(DbHelper.CART_PDT_NAME))));

为了在加载列表视图时存储 COUNT 值，请在 HashMap 中添加值(存储产品名称并对其进行计数)，无论何时增加或减少 COUNT 只需更新其在哈希图中的值

And for storing COUNT values when you loading listview add value in HashMap (which stores product name and count against it), after whenever you increase or decrease COUNT just update its value in hashmap

这篇关于滚动列表视图时 TextView 的值发生了变化的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！