How do I add a Control to a Container in an inherited WinForm

Question

I have a base form in another project that enforces the same look & feel to all our WinForms programs. I inherited from that BaseForm, to create my own template, BaseView. This template of mine has additional controls like a ProgressBar, a Timer and a TableLayoutPanel.

I now want to inherit from my BaseView and use the Designer to add my program-specific controls, however I cannot drop anything like Panels or any other Controls into it. I have tried some suggestions, like making sure the base form's components are public, but to no avail - most of the TLP's properties are still grayed out.

Could someone perhaps give me any suggestions? Many Thanks!

---

partial class BaseView
{
    /// <summary>
    /// Required designer variable.
    /// </summary>
    private System.ComponentModel.IContainer components = null;

    /// <summary>
    /// Clean up any resources being used.
    /// </summary>
    /// <param name="disposing">true if managed resources should be disposed; otherwise, false.</param>
    protected override void Dispose(bool disposing)
    {
        if (disposing && (components != null))
        {
            components.Dispose();
        }
        base.Dispose(disposing);
    }

    #region Windows Form Designer generated code

    /// <summary>
    /// Required method for Designer support - do not modify
    /// the contents of this method with the code editor.
    /// </summary>
    private void InitializeComponent()
    {
        this.components = new System.ComponentModel.Container();
        System.ComponentModel.ComponentResourceManager resources = new System.ComponentModel.ComponentResourceManager(typeof(BaseView));
        this.tableLayoutPanel_Form = new System.Windows.Forms.TableLayoutPanel();
        this.panel_Buttons = new System.Windows.Forms.Panel();
        this.panel_MainBody = new System.Windows.Forms.Panel();
        this.progressBar = new System.Windows.Forms.ProgressBar();
        this.timer_ProgressBar = new System.Windows.Forms.Timer(this.components);
        this.tableLayoutPanel_Form.SuspendLayout();
        this.SuspendLayout();
        // 
        // lblFormId
        // 
        this.lblFormId.AutoSize = false;
        this.lblFormId.Location = new System.Drawing.Point(390, 9);
        this.lblFormId.Size = new System.Drawing.Size(98, 13);
        this.lblFormId.TextAlign = System.Drawing.ContentAlignment.MiddleRight;
        // 
        // btnClose
        // 
        this.btnClose.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Top | System.Windows.Forms.AnchorStyles.Right)));
        this.btnClose.DialogResult = System.Windows.Forms.DialogResult.Cancel;
        this.btnClose.Location = new System.Drawing.Point(447, 5);
        this.btnClose.Size = new System.Drawing.Size(41, 21);
        this.btnClose.TabIndex = 4;
        // 
        // tableLayoutPanel_Form
        // 
        this.tableLayoutPanel_Form.ColumnCount = 1;
        this.tableLayoutPanel_Form.ColumnStyles.Add(new System.Windows.Forms.ColumnStyle(System.Windows.Forms.SizeType.Percent, 100F));
        this.tableLayoutPanel_Form.Controls.Add(this.panel_Buttons, 0, 2);
        this.tableLayoutPanel_Form.Controls.Add(this.panel_MainBody, 0, 1);
        this.tableLayoutPanel_Form.Dock = System.Windows.Forms.DockStyle.Fill;
        this.tableLayoutPanel_Form.Location = new System.Drawing.Point(0, 0);
        this.tableLayoutPanel_Form.Name = "tableLayoutPanel_Form";
        this.tableLayoutPanel_Form.RowCount = 3;
        this.tableLayoutPanel_Form.RowStyles.Add(new System.Windows.Forms.RowStyle(System.Windows.Forms.SizeType.Absolute, 30F));
        this.tableLayoutPanel_Form.RowStyles.Add(new System.Windows.Forms.RowStyle(System.Windows.Forms.SizeType.Percent, 100F));
        this.tableLayoutPanel_Form.RowStyles.Add(new System.Windows.Forms.RowStyle(System.Windows.Forms.SizeType.Absolute, 30F));
        this.tableLayoutPanel_Form.Size = new System.Drawing.Size(496, 322);
        this.tableLayoutPanel_Form.TabIndex = 26;
        // 
        // panel_Buttons
        // 
        this.panel_Buttons.Dock = System.Windows.Forms.DockStyle.Fill;
        this.panel_Buttons.Location = new System.Drawing.Point(3, 295);
        this.panel_Buttons.Name = "panel_Buttons";
        this.panel_Buttons.Size = new System.Drawing.Size(490, 24);
        this.panel_Buttons.TabIndex = 0;
        // 
        // panel_MainBody
        // 
        this.panel_MainBody.Dock = System.Windows.Forms.DockStyle.Fill;
        this.panel_MainBody.Location = new System.Drawing.Point(3, 33);
        this.panel_MainBody.Name = "panel_MainBody";
        this.panel_MainBody.Size = new System.Drawing.Size(490, 256);
        this.panel_MainBody.TabIndex = 1;
        // 
        // progressBar
        // 
        this.progressBar.Anchor = ((System.Windows.Forms.AnchorStyles)((System.Windows.Forms.AnchorStyles.Bottom | System.Windows.Forms.AnchorStyles.Right)));
        this.progressBar.Location = new System.Drawing.Point(383, 324);
        this.progressBar.Name = "progressBar";
        this.progressBar.Size = new System.Drawing.Size(112, 21);
        this.progressBar.TabIndex = 27;
        // 
        // timer_ProgressBar
        // 
        this.timer_ProgressBar.Interval = 700;
        this.timer_ProgressBar.Tick += new System.EventHandler(this.timer_Tick);
        // 
        // BaseView
        // 
        this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
        this.CancelButton = this.btnClose;
        this.ClientSize = new System.Drawing.Size(496, 346);
        this.Controls.Add(this.progressBar);
        this.Controls.Add(this.tableLayoutPanel_Form);
        this.Cursor = System.Windows.Forms.Cursors.Default;
        this.Icon = ((System.Drawing.Icon)(resources.GetObject("$this.Icon")));
        this.MinimumSize = new System.Drawing.Size(512, 384);
        this.Name = "BaseView";
        this.Controls.SetChildIndex(this.btnClose, 0);
        this.Controls.SetChildIndex(this.tableLayoutPanel_Form, 0);
        this.Controls.SetChildIndex(this.lblFormId, 0);
        this.Controls.SetChildIndex(this.lblFormDescription, 0);
        this.Controls.SetChildIndex(this.progressBar, 0);
        this.tableLayoutPanel_Form.ResumeLayout(false);
        this.ResumeLayout(false);
        this.PerformLayout();

    }

    #endregion

    private System.Windows.Forms.ProgressBar progressBar;
    private System.Windows.Forms.Timer timer_ProgressBar;
    public System.Windows.Forms.TableLayoutPanel tableLayoutPanel_Form;
    public System.Windows.Forms.Panel panel_Buttons;
    public System.Windows.Forms.Panel panel_MainBody;
}

Answer 1

This MSDN article gave me the answer.

"Not all controls support visual inheritance from a base form. The following controls do not support the scenario described in this walkthrough: WebBrowser, ToolStrip, ToolStripPanel, TableLayoutPanel, FlowLayoutPanel, DataGridView. These controls in the inherited form are always read-only regardless of the modifiers you use (private, protected, or public)."

I used a docked Panel and a SplitContainer instead of a TLP, and now I can drop anything I want into them.