Myujth

I am getting data from a web service and I am loading it in Picker. Now I want to call a new web service to get some data related to selected item. But I am not getting that selected item.

I am using below class model to get data from web service and loading it in Picker.

public class ModelGetEmployeeList

 public string ServiceStatus get; set; 
 public List<EmployeeList> EmpList get; set; 


public class EmployeeList

 public string uid get; set; 
 public string fname get; set; 
 public string lname get; set; 

This is how I loaded data in Picker:

if (response.IsSuccessStatusCode)

 var content = await response.Content.ReadAsStringAsync ();
 var Items = JsonConvert.DeserializeObject <ModelGetEmployeeList> (content);

 foreach(EmployeeList emp in Items.EmpList)
 
 pickerEmployee.Items.Add(emp.uid.ToString()+"-"+emp.fname.ToString()+" "+emp.lname.ToString());
 

Now I am implementing SelectedIndexChanged event like this:

public void PickerEmployee_SelectedIndexChanged(object sender, SelectedItemChangedEventArgs e)

 if (pickerEmployee.SelectedIndex == -1) 
 
 //Message
 
 else
 
 var item = sender as EmployeeList;
 var selectedItem = item.uid;

 DisplayAlert (selectedItem.ToString (), "OK", "OK");
 

But its giving me an error that above method has wrong signature.

According to the Xamarin.Forms Picker documentation SelectedIndexChanged event is expecting delegate which matches EventHandler delegate (EventHandler documentation)

So, you have to change signature of your method :

public void PickerEmployee_SelectedIndexChanged(object sender, EventArgs e)

 ...

Your signature is wrong.

Also the following code is wrong:

var item = sender as EmployeeList;
var selectedItem = item.uid;

Please find the corrected version below :

 public void PickerEmployee_SelectedIndexChanged(object sender, EventArgs e)
 
 if (pickerEmployee.SelectedIndex == -1) 
 
 //Message
 
 else
 
 var selectedItem = PickerEmployee[SelectedIndex]; 
 DisplayAlert (selectedItem, "OK", "OK");
 
 

The Xamarin Forms picker will get you only the string which was added to the list and not the object.

If you need the object either you can use the selectedIdex on your orginal lsit to get the object as :

var selectedEmp = Items.EmpList[SelectedIndex];

Or you can use a Bindable Picker.

You can take sellected value with this:

 string selectedEmployee = string.Empty; 

 selectedEmployee = pickerEmployee.Items[pickerEmployee.SelectedIndex];

public void PickerEmployee_SelectedIndexChanged(object sender, EventArgs e)

 if (pickerEmployee.SelectedIndex == -1) 
 
 //Message
 
 else
 
 var selectedItem = (EmployeeList)PickerEmployee.SelectedItem; 
 DisplayAlert (selectedItem.fname, "OK", "OK");
 

The Items collection is a list of strings so you can get the currently selected value using SelectedIndex

 var selectedValue = picker.Items [picker.SelectedIndex];

If you are using binding then yes, the exposed property is the SelectedIndex.

For more info click here

public void PickerEmployee_SelectedIndexChanged(object sender, SelectedItemChangedEventArgs e)

 if (pickerEmployee.SelectedIndex == -1) 
 
 //Message
 
 else
 
 var item = sender as Picker;
 var selectedItem = item.SelectedItem as EmployeeList;
 var uid =selectedItem.uid;
 DisplayAlert (uid .ToString (), "OK", "OK");