“Step-by-Step Tutorial: Building Dynamic User Interfaces with TAdvScrollBox” guides Embarcadero Delphi and C++Builder developers through using the TAdvScrollBox component from the TMS VCL UI Pack to build runtime-generated, scrollable dashboards, forms, and lists. TAdvScrollBox fixes limitations of the native VCL TScrollBox by adding features like built-in smooth scrolling, modern skinning, mouse-wheel support, and touch friendliness.
The workflow uses an architectural approach similar to modern “state-driven” component layouts, mapping database fields or application state to repeatable user frames. Phase 1: Designing the Layout Architecture
Instead of dropping individual buttons or text inputs directly into the scroll box at runtime, you must isolate your repeating UI chunks into modular containers.
Create a TFrame: In your IDE, select File > New > Other > Delphi Files > Frame.
Design the Base Template: Populate this Frame (e.g., TItemFrame) with the visual controls you need, such as labels, buttons, or image blocks.
Configure Alignment: Set the Frame’s Align property to alTop or alLeft. This ensures that when multiple instances are added to the scroll box, they stack perfectly without overlapping. Phase 2: Form Setup and Initialization
Drop a TAdvScrollBox from the tool palette onto your main form and tweak its properties to handle dynamic scaling cleanly:
AdvScrollBox1.AutoScroll := True; // Automatically handle visibility of scrollbars AdvScrollBox1.WheelEnable := True; // Enable seamless mouse wheel scrolling Use code with caution. Phase 3: Writing the Dynamic Insertion Code
To populate the UI dynamically (e.g., loading objects from a REST API, JSON file, or database), loop through your data source and instantiate your custom Frames programmatically.
Note: In the VCL, adding child components with alTop dynamically can sometimes reverse their insertion order. The best practice is to force the VCL layout engine to recalculate position explicitly via the SendToBack method or index manipulation.
procedure TMainForm.PopulateDynamicUI; var I: Integer; NewFrame: TItemFrame; begin // Disable screen updates to prevent flickering during mass layout changes AdvScrollBox1.BeginUpdate; try // Clear previous items if necessary AdvScrollBox1.ClearControls; for I := 1 to 10 do begin // 1. Create the instance of the frame NewFrame := TItemFrame.Create(Self); // 2. Assign the TAdvScrollBox as the visual parent NewFrame.Parent := AdvScrollBox1; // 3. Inject data into the frame’s UI elements NewFrame.lblTitle.Caption := ‘Dynamic Item #’ + IntToStr(I); NewFrame.lblStatus.Caption := ‘Active’; // 4. Force appropriate top-to-bottom stack sorting NewFrame.Align := alTop; NewFrame.SendToBack; end; finally // Re-enable screen drawing and refresh the scroll area layout AdvScrollBox1.EndUpdate; end; end; Use code with caution. Phase 4: Setting Up Event Handling
To capture user interactions from your dynamic UI (like clicking a button inside item #4), delegate the frame events back to the parent form:
Define a click signature in your TItemFrame class: FOnItemClick: TNotifyEvent;
Assign that handler during runtime creation: NewFrame.OnItemClick := Self.HandleMyFrameClick;
Identify which object sent the trigger inside the parent form method by casting the Sender variable: ClickedItem := (Sender as TButton).Parent as TItemFrame; Tips for Optimizing Performance
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