public delegate bool SelectedValueForDropDown (string name);
public partial class BasicTableViewSource : UITableViewSource
{
public override void RowSelected(UITableView tableView, MonoTouch.Foundation.NSIndexPath indexPath)
{
SelectedValueForDropDown selValue;
// Do something for the selected row
string itemSel = this._tableItems[indexPath.Section];
Console.WriteLine("90 the item selected is :{0}",itemSel);
DetailViewController dvc = new DetailViewController();
selValue = dvc.SelectedValueForPosition;
//bool val = dvc.SelectedValueForPosition(itemSel);
ValueSelectedDD valDD = new ValueSelectedDD();
bool success = valDD.HandleValueSelected(selValue);
Console.WriteLine("100 the value is : {0}",success);
}
.....
} //class closed
public class ValueSelectedDD
{
public bool HandleValueSelected (SelectedValueForDropDown selValue)
{
bool success =false;
success = selValue("CEO");
return success;
}
}
//This method is in DetailViewController.designer.cs class.
public bool SelectedValueForPosition (string name)
{
Console.WriteLine("the value selected is :{0}",name);
btnPosition.SetTitle(name,UIControlState.Normal); //Exception occurs here
return true;
}
I am working on simple MonoDevelop projects.So i have a tableview as pop up for my button. I click it and i have 3 options. I choose one and the button should get its label replaced by option selected. The row selected is in a tableviewsource class. DetailViewController is the class where i have the actual button to be clicked. I am getting an exception of
System.NullReferenceException: Object reference not set to an instance of an object
at EmployeeWithDropDown.DetailViewController.SelectedValueForPosition (System.String name) [0x0000b] in /Users/.../EmployeeWithDropDown/EmployeeWithDropDown/DetailViewController.designer.cs:106
at EmployeeWithDropDown.ValueSelectedDD.HandleValueSelected (EmployeeWithDropDown.SelectedValueForDropDown selValue) [0x00002] in /Users/.../EmployeeWithDropDown/EmployeeWithDropDown/BasicTableViewSource.cs:109
at EmployeeWithDropDown.BasicTableViewSource.RowSelected (MonoTouch.UIKit.UITableView tableView, MonoTouch.Foundation.NSIndexPath indexPath) [0x00036] in /Users/.../EmployeeWithDropDown/EmployeeWithDropDown/BasicTableViewSource.cs:99
at (wrapper managed-to-native) MonoTouch.UIKit.UIApplication:UIApplicationMain (int,string[],intptr,intptr)
at MonoTouch.UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) [0x0004c] in /Developer/MonoTouch/Source/monotouch/src/UIKit/UIApplication.cs:38
at EmployeeWithDropDown.Application.Main (System.String[] args) [0x00000] in /Users/.../EmployeeWithDropDown/EmployeeWithDropDown/Main.cs:17
System.NullReferenceException has been thrown.
Object Reference not set to an instance of an object.
if you need more info, please ask. Thanks.
EDIT:
public partial class PopoverContentViewcontroller : UIViewController
{
public override void ViewDidLoad ()
{
base.ViewDidLoad ();
table = new UITableView(View.Bounds);
table.AutoresizingMask = UIViewAutoresizing.All;
string[] tableItems = new string[]{"CEO","Developer","IT"};
//List<String> wordList = Arrays.asList(words);
List<string> lst = new List<string>(tableItems);
table.Source = new BasicTableViewSource(lst);
Add (table);
}
.....
}
This is the popovercontroller that populates the table for drop down. i.e. the values here get populated in the drop down ..
EDIT2:
DetailViewController dvc;
.....
table.Source = new BasicTableViewSource(lst,dvc);
Add (table);
You are creating a new instance of DetailViewController in your RowSelected method. What you need is a reference to the DetailViewController that already exists.
When you create your TableViewController, you need to pass in a reference to the "parent" DetailViewController. That way in your RowSelected method you can call a method on the already existing DVC.