datamodel must implement when selection is enabled.? - jsf

Question

I wanted to remove rows from the data table when the checkbox is ticked and remove button is pressed..
This is the datatable snippet :
<p:dataTable id="cartTable" lazy="true" scrollable="true"
scrollHeight="115" selection="#{Cart_Check.selectedItems}"
value="#{Cart_Check.cart}" var="cart" rowKey="#{cart.sheetno}"
style="widht:100%;margin-top:10%;margin-left:1%;margin-right:30px ;box-shadow: 10px 10px 25px #888888;">
<f:facet name="header">
Checkbox Based Selection
</f:facet>
<p:column selectionMode="multiple" style="width:2%">
</p:column>
//Here the columns are metion
<f:facet name="footer">
<p:commandButton id="viewButton" value="Remove" />
</f:facet>
</p:dataTable>
This is the backing bean
public class checkcart {
private int items;
private ArrayList<User_Cart> cart;
private ArrayList<User_Cart> selectedItems;
public checkcart() {
getvalues();
}
//getter and setter
public void getvalues() {
FacesContext context = FacesContext.getCurrentInstance();
HttpSession session = (HttpSession) context.getExternalContext()
.getSession(false);
System.out.println("Cart Request ::::" + session.getAttribute("regid"));
try {
Connection connection = BO_Connector.getConnection();
String sql = "Select * from cart_orderinfo where usrregno=?";
PreparedStatement ps = connection.prepareStatement(sql);
ps.setString(1, (String) session.getAttribute("regid"));
ResultSet rs = ps.executeQuery();
cart = new ArrayList<>();
while (rs.next()) {
User_Cart user_cart = new User_Cart();
user_cart.setSheetno(rs.getString("sheetno"));
user_cart.setState_cd(rs.getString("state_cd"));
user_cart.setDist_cd(rs.getString("dist_cd"));
user_cart.setLicensetype(rs.getString("license_type"));
user_cart.setFormat(rs.getString("sheet_format"));
user_cart.setQuantity(rs.getInt("quantity"));
cart.add(user_cart);
}
} catch (Exception ex) {
System.out.println(ex);
}
}
}
and when i run this page i get the following error
datamodel must implement org.primefaces.model.selectabledatamodel when selection is enabled.
But when i remove the checkbox then their is no error but it is without a checkbox.
What to do and how to resolve the following error ..Kindly help..
I want something like this :
http://www.primefaces.org/showcase/ui/datatableRowSelectionRadioCheckbox.jsf

Answer 1

You just need to define ListDataModel as shown below,
public class SD_User_Cart extends ListDataModel<User_Cart> implements SelectableDataModel<User_Cart> {
public SD_User_Cart() {
}
public SD_User_Cart(List<User_Cart> data) {
super(data);
}
#Override
public User_Cart getRowData(String rowKey) {
//In a real app, a more efficient way like a query by rowKey should be implemented to deal with huge data
List<User_Cart> rows = (List<User_Cart>) getWrappedData();
for (User_Cart row : rows) {
if (row.getCartId.toString().equals(rowKey)) {//CartId is the primary key of your User_Cart
return row;
}
}
return null;
}
#Override
public Object getRowKey(User_Cart row) {
return row.get.getCartId();
}
}
Change your "cart" object into SD_User_Cart as shown below,
private SD_User_Cart cart;
Then define selection in p:datatable, and add a column as shown below,
<p:column selectionMode="multiple" style="width:18px"/>
Hope this helps:)

Answer 2

You need to define a your private ArrayList<User_Cart> selectedItems; data member in back class public class checkcart like this private User_Cart[] selectedItems; and give setter and getter method for the same it will work.
I had also faced same problem.