DockPanel.md

DockPanel

DockPanel is the central control of the AcrylicUI docking framework. It manages the layout of dockable content (documents and tool windows) within regions (Document, Left, Right, Bottom) and handles splitting and rearranging.

Basic Usage

Typically, you add a single DockPanel to your main form, usually docked to fill a container like WindowPanel. You then create instances of DockContent (or derived classes like Document or ToolWindow) and add them to the DockPanel using the AddContent method.

Important: You must add the DockPanel.DockResizeFilter to your application's message filters for docking resize operations (like dragging splitters) to work correctly.

using AcrylicUI.Docking;
using AcrylicUI.Forms;
using AcrylicUI.Controls; // For WindowPanel if used
using System.Windows.Forms;

public partial class MyMainForm : AcrylicForm
{
    private WindowPanel mainContainerPanel; // Optional container
    private AcrylicUI.Docking.DockPanel dockPanel;

    // Example content windows
    private MyToolWindow toolWindow1;
    private MyDocument document1;
    private MyDocument document2;

    public MyMainForm()
    {
        InitializeComponent();

        // Add the required message filter ONCE in application startup
        // (e.g., in Program.cs before Application.Run)
        // Application.AddMessageFilter(AcrylicUI.Docking.DockPanel.DockResizeFilter);
        // Alternatively, if added here, ensure it's only added once.
        if (!Application.MessageLoop)
           Application.AddMessageFilter(AcrylicUI.Docking.DockPanel.DockResizeFilter);

        // Setup DockPanel (often done in designer)
        dockPanel = new AcrylicUI.Docking.DockPanel
        {
            Dock = DockStyle.Fill, 
            BackColor = AcrylicUI.Resources.Colors.GreyBackground // Or other theme color
        };
        
        // Add to form or a container panel
        // Assuming mainContainerPanel fills the form below Menu/ToolStrips
        if (mainContainerPanel != null)
             mainContainerPanel.Controls.Add(dockPanel); 
        else 
             Controls.Add(dockPanel);
        
        // Create and add content
        toolWindow1 = new MyToolWindow { DefaultDockArea = DockArea.Left }; // Specify default area
        document1 = new MyDocument { DockText = "Document A" }; // Documents default to Document area
        document2 = new MyDocument { DockText = "Document B" };

        dockPanel.AddContent(toolWindow1); // Add tool window
        dockPanel.AddContent(document1); // Add document
        dockPanel.AddContent(document2); // Add another document
        
        // DockPanel handles layout automatically
    }
}

// Example Content Classes (must inherit from DockContent)
public class MyToolWindow : ToolWindow 
{ 
    public MyToolWindow() { /* Add controls here */ } 
}
public class MyDocument : Document 
{ 
    public MyDocument() { /* Add controls here */ } 
}

Key Methods

• AddContent(DockContent content): Adds a dockable window (ToolWindow or Document) to the panel, placing it in its DefaultDockArea or the Document area if unspecified.
• RemoveContent(DockContent content): Removes a previously added content window.
• GetDocuments(): Returns a list of all DockContent items currently in the Document area.
• LoadDockState(Stream stream), SaveDockState(Stream stream): Methods for serializing and deserializing the layout of docked windows.

Key Properties

• ActiveContent: Gets or sets the currently focused DockContent.
• ActiveDocument: Gets the currently focused DockContent within the Document area.
• BackColor: Sets the background color for the panel's empty areas and splitters.

Key Events

• ActiveContentChanged: Occurs when the focused content changes.
• ContentAdded, ContentRemoved: Occur when content is added to or removed from the panel.

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See also: DockContent, Document, ToolWindow, Example Form Form6_DockPanel.cs