> For clean Markdown of any page, append .md to the page URL. > For a complete documentation index, see https://docs.ninjatrader.com/llms.txt. > For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.ninjatrader.com/_mcp/server. # UserControlCollection ## Definition An [observable collection](https://msdn.microsoft.com/en-us/library/ms668604\(v=vs.110\).aspx) of 3rd party [framework elements](https://msdn.microsoft.com/en-us/library/system.windows.frameworkelement\(v=vs.110\).aspx), the purpose of which is to allow developers to add a custom control to the chart (e.g., add a button or create your own data grid). This framework collection resides on top of the [ChartControl](/developer/desktop-sdk/references/common/charts/chartcontrol) in order to prevent 3rd party custom controls from interfering with native NinjaTrader chart framework members. For example, if you wish to add a button to a chart, it is recommended to add it to this UserControlCollection rather than attempting to modify or add to any pre-existing NinjaTrader chart elements. 1. This collection is provided "as-is" and does NOT contain any automatic layout options. By default, the last added framework element will reside on top of any previously added controls. This means it is possible for a user to install two NinjaScript objects which may be competing for an area of a chart. 2. Once the NinjaScript object is removed from the chart by the user, the custom control will be automatically removed from the collection. 1) This property should ONLY be accessed once your NinjaScript object has reached State.Historical or later 2) You MUST use a [Dispatcher](https://msdn.microsoft.com/en-us/library/system.windows.threading.dispatcher\(v=vs.110\).aspx) in order to account for any UI threading errors. Please see the example below for proper usage 3) It is imperative that you dispose of any custom control resources in State.Terminated to ensure there are no leaks between instances of the object ## Property Value ObservableCollection\ ## Syntax `UserControlCollection[int idx]` ## Examples ```csharp private System.Windows.Controls.Button myBuyButton; private System.Windows.Controls.Button mySellButton; private System.Windows.Controls.Grid myGrid; // Define a custom event method to handle our custom task when the button is clicked private void OnMyButtonClick(object sender, RoutedEventArgs rea) { System.Windows.Controls.Button button = sender as System.Windows.Controls.Button; if (button != null) Print(button.Name + " Clicked"); } protected override void OnStateChange() { if (State == State.SetDefaults) { Name = "SampleAddButton"; Description = "Adds a custom control to the chart"; IsOverlay = true; } else if (State == State.Configure) { } // Once the NinjaScript object has reached State.Historical, our custom control can now be added to the chart else if (State == State.Historical) { // Because we're dealing with UI elements, we need to use the Dispatcher which created the object // otherwise we will run into threading errors... // e.g, "Error on calling 'OnStateChange' method: You are accessing an object which resides on another thread." // Furthermore, we will do this operation Asynchronously to avoid conflicts with internal NT operations ChartControl.Dispatcher.InvokeAsync((() => { // Grid already exists if (UserControlCollection.Contains(myGrid)) return; // Add a control grid which will host our custom buttons myGrid = new System.Windows.Controls.Grid { Name = "MyCustomGrid", // Align the control to the top right corner of the chart HorizontalAlignment = HorizontalAlignment.Right, VerticalAlignment = VerticalAlignment.Top, }; // Define the two columns in the grid, one for each button System.Windows.Controls.ColumnDefinition column1 = new System.Windows.Controls.ColumnDefinition(); System.Windows.Controls.ColumnDefinition column2 = new System.Windows.Controls.ColumnDefinition(); // Add the columns to the Grid myGrid.ColumnDefinitions.Add(column1); myGrid.ColumnDefinitions.Add(column2); // Define the custom Buy Button control object myBuyButton = new System.Windows.Controls.Button { Name = "MyBuyButton", Content = "LONG", Foreground = Brushes.White, Background = Brushes.Green }; // Define the custom Sell Button control object mySellButton = new System.Windows.Controls.Button { Name = "MySellButton", Content = "SHORT", Foreground = Brushes.White, Background = Brushes.Red }; // Subscribe to each buttons click event to execute the logic we defined in OnMyButtonClick() myBuyButton.Click += OnMyButtonClick; mySellButton.Click += OnMyButtonClick; // Define where the buttons should appear in the grid System.Windows.Controls.Grid.SetColumn(myBuyButton, 0); System.Windows.Controls.Grid.SetColumn(mySellButton, 1); // Add the buttons as children to the custom grid myGrid.Children.Add(myBuyButton); myGrid.Children.Add(mySellButton); // Finally, add the completed grid to the custom NinjaTrader UserControlCollection UserControlCollection.Add(myGrid); })); } // When NinjaScript object is removed, make sure to unsubscribe to button click events else if (State == State.Terminated) { if (ChartControl == null) return; // Again, we need to use a Dispatcher to interact with the UI elements ChartControl.Dispatcher.InvokeAsync((() => { if (myGrid != null) { if (myBuyButton != null) { myGrid.Children.Remove(myBuyButton); myBuyButton.Click -= OnMyButtonClick; myBuyButton = null; } if (mySellButton != null) { myGrid.Children.Remove(mySellButton); mySellButton.Click -= OnMyButtonClick; mySellButton = null; } } })); } } ``` ![AddOnFrameWorkExample2](https://fdr-prod-docs-files-public.s3.us-east-1.amazonaws.com/ninjatrader-public.docs.buildwithfern.com/309444589ad79ab1c7d0eb272696c63c02799b1e6698af34d6347b3884e3f2de/docs/assets/developer/desktop-sdk/references/usercontrolcollection-addonframeworkexample2.png?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Content-Sha256=UNSIGNED-PAYLOAD&X-Amz-Credential=AKIA6KXJSKKNFOCF7G4B%2F20260729%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20260729T062231Z&X-Amz-Expires=604800&X-Amz-Signature=f5f8028a0a8800e6ac6aa0744ce60d7510b652f1aa8e72e00b6f4ae9e158db6e&X-Amz-SignedHeaders=host&x-amz-checksum-mode=ENABLED&x-id=GetObject)