Multiple tabs in rootview - ipad

Question

I am very new to XCode and Monotouch development. I am trying to add multiple tabs in root view (Master-Detail application). I am using Mono for development and xCode 4 for UI design. For example, one tab shows list of employees and another tab shows list of departments.
I removed the default table view in the rootviewController.xib file and replaced with tabbedview but I cant get new table view for each tab working.
I would appreciate if anyone can show me the correct way of doing this.
UPDATED: I use the code below to add 2 tabs and 2 table view. One is to hold "Securities" and the other one to hold the "Indicators"
using System;
using System.Drawing;
using MonoTouch.Foundation;
using MonoTouch.UIKit;
using System.Collections.Generic;
namespace ChartQ
{
public partial class RootViewController : UITabBarController
{
public DetailViewController DetailVC { get; set; }
private List<SecurityInfo> listSecInfo = new List<SecurityInfo>();
private List<Indicator> listIndicator = new List<Indicator>();
public RootViewController () : base ("RootViewController", null)
{
this.Title = NSBundle.MainBundle.LocalizedString ("Securities", "Securities");
//this.ClearsSelectionOnViewWillAppear = false;
this.ContentSizeForViewInPopover = new SizeF (100f, 200f);
//this.ContentSizeForViewInPopover = new SizeF (320f, 600f);
// Custom initialization
}
public override void ViewDidLoad ()
{
base.ViewDidLoad ();
//Read data from Database..
UITableViewController secController = new UITableViewController();
UITableViewController IndiController = new UITableViewController();
this.AddChildViewController(secController);
this.AddChildViewController(IndiController);
SQLLiteDatabase db = new SQLLiteDatabase();
listSecInfo = db.ReadSecurities();
listIndicator = db.ReadIndicator();
//TableView.Source = new SecuritiesDataSource (this);
secController.TableView.Source = new SecuritiesDataSource (this);
secController.TableView.SelectRow (NSIndexPath.FromRowSection (0, 0), false, UITableViewScrollPosition.Middle);
IndiController.TableView.Source = new IndicatorDataSource (this);
IndiController.TableView.SelectRow (NSIndexPath.FromRowSection (0, 0), false, UITableViewScrollPosition.Middle);
}
public override bool ShouldAutorotateToInterfaceOrientation (UIInterfaceOrientation toInterfaceOrientation)
{
// Return true for supported orientations
return true;
}
public override void DidReceiveMemoryWarning ()
{
// Releases the view if it doesn't have a superview.
base.DidReceiveMemoryWarning ();
// Release any cached data, images, etc that aren't in use.
}
public override void ViewDidUnload ()
{
base.ViewDidUnload ();
// Clear any references to subviews of the main view in order to
// allow the Garbage Collector to collect them sooner.
//
// e.g. myOutlet.Dispose (); myOutlet = null;
ReleaseDesignerOutlets ();
}
class SecuritiesDataSource : UITableViewSource
{
static NSString cellIdentifier = new NSString ("CellId");
RootViewController controller;
public SecuritiesDataSource (RootViewController controller)
{
this.controller = controller;
}
// Customize the number of sections in the table view.
public override int NumberOfSections (UITableView tableView)
{
return 1;
}
public override int RowsInSection (UITableView tableview, int section)
{
return controller.listSecInfo.Count;
}
public override string TitleForHeader (UITableView tableView, int section)
{
return "Securities";
}
// Customize the appearance of table view cells.
public override UITableViewCell GetCell (UITableView tableView, MonoTouch.Foundation.NSIndexPath indexPath)
{
string cellIdentifier = "Cell";
var cell = tableView.DequeueReusableCell (cellIdentifier);
if (cell == null) {
cell = new UITableViewCell (UITableViewCellStyle.Subtitle, cellIdentifier);
//Add in a detail disclosure icon to each cell
cell.Accessory = UITableViewCellAccessory.DetailDisclosureButton;
}
// Configure the cell.
var sInfo = controller.listSecInfo [indexPath.Row];
cell.TextLabel.Text = String.Format ("{0}",sInfo.SecCode);
cell.DetailTextLabel.Text = sInfo.SecName;
return cell;
}
private void InfoAlert (string msg)
{
using (UIAlertView av = new UIAlertView("Info", msg, null, "OK", null)) {
av.Show ();
}
}
public override void RowSelected (UITableView tableView, NSIndexPath indexPath)
{
var sInfo = controller.listSecInfo [indexPath.Row];
controller.DetailVC.DrawChart(sInfo.SecID, sInfo.SecCode);
}
}
class IndicatorDataSource : UITableViewSource
{
static NSString cellIdentifier = new NSString ("CellId");
RootViewController controller;
public IndicatorDataSource (RootViewController controller)
{
this.controller = controller;
}
// Customize the number of sections in the table view.
public override int NumberOfSections (UITableView tableView)
{
return 1;
}
public override int RowsInSection (UITableView tableview, int section)
{
return controller.listIndicator.Count;
}
public override string TitleForHeader (UITableView tableView, int section)
{
return "Indicators";
}
// Customize the appearance of table view cells.
public override UITableViewCell GetCell (UITableView tableView, MonoTouch.Foundation.NSIndexPath indexPath)
{
string cellIdentifier = "Cell";
var cell = tableView.DequeueReusableCell (cellIdentifier);
if (cell == null) {
cell = new UITableViewCell (UITableViewCellStyle.Subtitle, cellIdentifier);
//Add in a detail disclosure icon to each cell
cell.Accessory = UITableViewCellAccessory.DetailDisclosureButton;
}
// Configure the cell.
var sInfo = controller.listIndicator [indexPath.Row];
cell.TextLabel.Text = String.Format ("{0}",sInfo.DescriptiveName);
cell.DetailTextLabel.Text = sInfo.ShortName;
return cell;
}
private void InfoAlert (string msg)
{
using (UIAlertView av = new UIAlertView("Info", msg, null, "OK", null)) {
av.Show ();
}
}
public override void RowSelected (UITableView tableView, NSIndexPath indexPath)
{
var sInfo = controller.listIndicator [indexPath.Row];
//controller.DetailVC.DrawChart(sInfo.SecID, sInfo.SecCode);
}
}
}
However, it crashes when I click the second tab. I am getting the error as below
"Got a SIGSEGV while executing native code"
The first list populated ok.

Answer 1

I think the UITableViewController objects are getting collected and causing your abort. Make secController and secController member variables.
public partial class RootViewController : UITabBarController
{
UITableViewController secController;
UITableViewController IndiController;
public DetailViewController DetailVC { get; set; }
...
public override void ViewDidLoad ()
{
base.ViewDidLoad ();
//Read data from Database..
secController = new UITableViewController ();
IndiController = new UITableViewController ();