C# updating usercontrol library will remove inner content

Question

I have a very very annoying problem!

In my user control library I have a control with a panel inside, which can take content. If I build this dll and reference it to an project I normally can use this control and also add content to it. Now the problem: Everytime I build a new version of this control library and update/override the dll in the project I use this dll the control with the content will be rebuild and now the content is removed. How to fix this?

Best regards

Sven König

EDIT 1
Note: the panel I mean is a user control which have a Windows.Forms.Panel to store the content. The designer of this user control is a "ParentControlDesigner".

EDIT 2
Sorry, the control to save to content is directly saved to the user control which is designed through ParentControlDesigner. I've done this because if i use a Windows.Forms.Panel I have resizing options at design time. And this i don't want.

EDIT 3
Here is the Code for the GroupBox, where the content control is inside...

[Designer(typeof(BorderedGroupBoxDesigner))]
public partial class BorderedGroupBox : UserControl
{
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
    internal Panel GroupingPanel { get; }

    [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
    internal readonly Label TitelLabel;

    private VisualStyleRenderer _renderer;

    /// <summary>
    /// Initializes the Control.
    /// </summary>
    public BorderedGroupBox()
    {
        InitializeComponent();

        //Create TitleLabel
        TitelLabel = new Label
        {
            Location = new Point(1, 1),
            AutoSize = false,
            TextAlign = ContentAlignment.MiddleLeft
        };

        //Create GroupingPanel
        GroupingPanel = new Panel
        {
            Location = new Point(1, TitleHeight - 1)
        };

        //Create Container and add Panel
        Control container = new ContainerControl
        {
            Dock = DockStyle.Fill,
            Padding = new Padding(-1),
            Controls = {TitelLabel, GroupingPanel}
        };

        //Add container and it's content to this control
        Controls.Add(container);

        //Set sizes of inner controls
        TitelLabel.Size = new Size(Size.Width - 2, 20);
        GroupingPanel.Size = new Size(Size.Width - 2, Size.Height - TitleHeight - 3);

        //Set anchor of inner controls
        TitelLabel.Anchor = AnchorStyles.Top | AnchorStyles.Left | AnchorStyles.Right;
        GroupingPanel.Anchor = AnchorStyles.Top | AnchorStyles.Bottom | AnchorStyles.Left | AnchorStyles.Right;

        //Value defaults
        BackgroundColor = SystemColors.Window;
        BorderColor = SystemColors.GradientActiveCaption;
        TitleBackColor = Color.FromKnownColor(KnownColor.DodgerBlue);
        TitleFont = new Font("Calibri", TitleHeight - 9, FontStyle.Bold);
        TitleFontColor = SystemColors.Window;
    }

    //Make default prope rty "BackColor" unvisible
    [Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public sealed override Color BackColor { get; set; }

    //Use "BackgroundColor" instead of default "BackColor"
    /// <returns>The BackgroundColor associated with this control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("The backgroundcolor of the component.")]
    [Category("Appearance")]
    [DefaultValue(typeof(Color), "Window")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public Color BackgroundColor { get { return GroupingPanel.BackColor; } set { GroupingPanel.BackColor = value; } }

    /// <returns>The BorderColor associated with this control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the border color.")]
    [Category("Appearance")]
    [DefaultValue(typeof(Color), "GradientActiveCaption")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public Color BorderColor { get { return BackColor; } set { BackColor = value; } }

    /// <returns>The BorderColor of the title associated with this control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the title color.")]
    [Category("Appearance")]
    [DefaultValue(typeof(Color), "DodgerBlue")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public Color TitleBackColor { get { return TitelLabel.BackColor; } set { TitelLabel.BackColor = value; } }

    /// <returns>The height of the title associated with this control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the title height in px.")]
    [Category("Appearance")]
    [DefaultValue(typeof(int), "20")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public int TitleHeight
    {
        get { return TitelLabel.Size.Height; }
        set
        {
            TitelLabel.Size = new Size(TitelLabel.Size.Width, value);
            GroupingPanel.Location = new Point(GroupingPanel.Location.X, value + 2);
            GroupingPanel.Size = new Size(GroupingPanel.Size.Width, Size.Height - value - 3);
        }
    }

    /// <returns>The font of the title associated with this control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the title font.")]
    [Category("Appearance")]
    [DefaultValue(typeof(Font), "Calibri; 11pt; style=Bold")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public Font TitleFont { get { return TitelLabel.Font; } set { TitelLabel.Font = value; } }

    /// <returns>The ForeColor (color of the text) of the title associated with this control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the title font color.")]
    [Category("Appearance")]
    [DefaultValue(typeof(Color), "Window")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public Color TitleFontColor { get { return TitelLabel.ForeColor; } set { TitelLabel.ForeColor = value; } }

    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the title text.")]
    [Category("Appearance")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public override string Text { get { return TitelLabel.Text; } set { TitelLabel.Text = value; } }

    /// <returns>Sets visibility of the design grid to easily align controls on grid.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets visibility of the design grid to easily align controls on grid.")]
    [Category("Design")]
    [DesignOnly(true)]
    [DefaultValue(typeof(bool), "false")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public bool ShowDesignGrid
    {
        get { return GroupingPanel.Designer.DrawGridState; }
        set
        {
            if (value)
                GroupingPanel.Designer.EnableDrawGrid();
            else
                GroupingPanel.Designer.DisableDrawGrid();

            Refresh();
        }
    }

    /// <returns>Sets visibility of the design grid to easily align controls on grid.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets size of the design grid.")]
    [Category("Design")]
    [DesignOnly(true)]
    [DefaultValue(typeof(Size), "8; 8")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public string DesignGridSize
    {
        get { return $"{GroupingPanel.Designer.GridSize.Width}; {GroupingPanel.Designer.GridSize.Height}"; }
        set
        {
            var values = value.Split(';');

            GroupingPanel.Designer.GridSize = new Size(int.Parse(values[0]), int.Parse(values[1]));
        }
    }

    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public new Padding Padding
    {
        get { return GroupingPanel.Padding; }
        set { GroupingPanel.Padding = value; }
    }

    protected override void OnPaint(PaintEventArgs e)
    {
        base.OnPaint(e);

        if (!Focused || !Application.RenderWithVisualStyles) return;

        if (_renderer == null)
        {
            var elem = VisualStyleElement.Button.PushButton.Normal;
            _renderer = new VisualStyleRenderer(elem.ClassName, elem.Part, (int)PushButtonState.Normal);
        }

        var rc = _renderer.GetBackgroundContentRectangle(e.Graphics, new Rectangle(0, 0, Width, Height));
        rc.Height--;
        rc.Width--;

        using (var p = new Pen(Brushes.Purple))
        {
            e.Graphics.DrawRectangle(p, rc);
        }
    }
}

internal class BorderedGroupBoxDesigner : ControlDesigner
{
    internal static SelectionRulesEnum SelectionRule;

    public override void Initialize(IComponent component)
    {
        base.Initialize(component);

        EnableDragDrop(true);

        var uc = component as BorderedGroupBox;
        if (uc != null)
            EnableDesignMode(uc.GroupingPanel, "Panel");
    }

    public override SelectionRules SelectionRules
    {
        get
        {
            switch (SelectionRule)
            {
                case SelectionRulesEnum.All:
                    return SelectionRules.Visible | SelectionRules.Moveable | SelectionRules.AllSizeable;
                case SelectionRulesEnum.UpDown:
                    return SelectionRules.Visible | SelectionRules.Moveable | SelectionRules.TopSizeable | SelectionRules.BottomSizeable;
                case SelectionRulesEnum.RightLeft:
                    return SelectionRules.Visible | SelectionRules.Moveable | SelectionRules.LeftSizeable | SelectionRules.RightSizeable;
                case SelectionRulesEnum.None:
                    return SelectionRules.Visible | SelectionRules.Moveable;
                default:
                    return SelectionRules.Visible | SelectionRules.Moveable;
            }
        }
    }

    internal enum SelectionRulesEnum
    {
        All,
        UpDown,
        RightLeft,
        None
    }
}

And here is the "Panel"...

[Designer(typeof(NonSizeablePanel_ParentDesigner))]
internal partial class Panel : UserControl
{
    internal NonSizeablePanel_ParentDesigner Designer;

    internal Panel()
    {
        InitializeComponent();
    }

    [Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
    public new Point Location { get { return base.Location; } set { base.Location = value; } }

    [Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
    public new AnchorStyles Anchor { get { return base.Anchor; } set { base.Anchor = value; } }

    [Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
    public new Size Size { get { return base.Size; } set { base.Size = value; } }

    [Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
    public new bool AutoScroll { get { return base.AutoScroll; } set { base.AutoScroll = value; } }

    [Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
    public new Size AutoScrollMargin { get { return base.AutoScrollMargin; } set { base.AutoScrollMargin = value; } }

    [Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
    public new Size AutoScrollMinSize { get { return base.AutoScrollMinSize; } set { base.AutoScrollMinSize = value; } }

    [Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
    public new bool AutoSize { get { return base.AutoSize; } set { base.AutoSize = value; } }

    [Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
    public new DockStyle Dock { get { return base.Dock; } set { base.Dock = value; } }

    [Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
    public new Padding Margin { get { return base.Margin; } set { base.Margin = value; } }

    [Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
    public new Padding Padding { get { return base.Padding; } set { base.Padding = value; } }

    [Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
    public new Size MaximumSize { get { return base.MaximumSize; } set { base.MaximumSize = value; } }

    [Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
    public new Size MinimumSize { get { return base.MinimumSize; } set { base.MinimumSize = value; } }

    [Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
    public new bool Visible { get { return base.Visible; } set { base.Visible = value; } }

    [Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
    public new bool Enabled { get { return base.Enabled; } set { base.Enabled = value; } }
}

internal class NonSizeablePanel_ParentDesigner : ParentControlDesigner
{
    public override void Initialize(IComponent component)
    {
        base.Initialize(component);

        var userControl = component as Panel;

        if (userControl != null)
            userControl.Designer = this;
    }

    internal new Size GridSize
    {
        get { return base.GridSize; }
        set { base.GridSize = value; }
    }

    internal bool DrawGridState => DrawGrid;

    internal void EnableDrawGrid()
    {
        DrawGrid = true;
    }

    internal void DisableDrawGrid()
    {
        DrawGrid = false;
    }

    protected override bool DrawGrid { get; set; }

    //Disable any sizing grips
    public override SelectionRules SelectionRules => SelectionRules.None;
}

How are you saving the panel's contents? Some code would really make this a lot easier my friend. — Trey, Mar 13 '17 at 18:39
Please post your code, I'm a bit lost on what you are having issues with, and I suspect seeing your user control code with illuminate this. — Trey, Mar 13 '17 at 18:52
I'm wondering if your use of "Panel" as the name is an issue, if it cannot find yours it would use a standard panel. Off hand I'm not seeing any other red flags, are the projects that reference your DLL set to specific version? Maybe put some debug in to see what the type is on the "panel" when you do an overwrite? — Trey, Mar 13 '17 at 19:21
No, the projects are not referenced to specific versions. I only override the dll which is copied local to the projects. Then VS is registering this overriding and updating the designer Toolbox and all affected controls. And here.... the content in the GroupBox is deleted. — Sven König, Mar 13 '17 at 20:32
Ohh! I have discovered a new problem. Now if I build the project where the GroupBox is used, the content is not visible in runtime - in designer it is. — Sven König, Mar 13 '17 at 20:35
I'm going home for the night, will re-visit this tomorrow with fresh eyes :-) — Trey, Mar 13 '17 at 20:43
Thank you for Trey, very much :) I'm glad that any body help me with this issue. — Sven König, Mar 13 '17 at 20:48
Two searches look promising that I found: http://stackoverflow.com/questions/2694889/user-control-as-container-at-design-time and http://stackoverflow.com/questions/1356676/c-sharp-user-control-as-a-custom-panel — Trey, Mar 14 '17 at 12:34
How the first link says to do this works well if I use a Windows.Forms.Panel as container. But I use a UserControl which is created like the second link says... And then it doesn't work....... but why? >. — Sven König, Mar 14 '17 at 13:11
I've done it like the links you postet say. But it still doesn't work... — Sven König, Mar 14 '17 at 13:25
Update your code to your latest, I will troubleshoot on my end a bit. — Trey, Mar 14 '17 at 13:37

score 0 · Answer 1 · answered Mar 14 '17 at 13:59

Here is an update of my code.

Changes:
- now using standard Windows.Forms.Panel as control container.
- to avoid resizing or movement I've write code to the events "Resize" and "LocationChanged"

Here a picture of the result:
Current result

And here the current code:

[Designer(typeof(BorderedGroupBoxDesigner))]
public sealed partial class BorderedGroupBox : UserControl
{
    /// <summary>The Panel which stores the content controls.</summary>
    [Category("Behavior")]
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Content)]
    public readonly Panel ContentPanel;

    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    internal readonly Label TitelLabel;

    private VisualStyleRenderer _renderer;

    private int _contentPanelTop => TitleHeight - 1;

    private int _contentPanelLeft => 1;

    private int _contentPanelWidth => Size.Width - 2;

    private int _contentPanelHeight => Size.Height - TitleHeight - 3;

    /// <summary>
    /// Initializes the Control.
    /// </summary>
    public BorderedGroupBox()
    {
        InitializeComponent();

        //Create TitleLabel
        TitelLabel = new Label
        {
            Location = new Point(1, 1),
            AutoSize = false,
            TextAlign = ContentAlignment.MiddleLeft
        };

        //Create GroupingPanel
        ContentPanel = new Panel
        {
            Location = new Point(1, TitleHeight - 1)
        };

        //Create Container and add Panel
        Control container = new ContainerControl
        {
            Dock = DockStyle.Fill,
            Padding = new Padding(-1),
            Controls = {TitelLabel, ContentPanel}
        };

        //Add container and it's content to this control
        Controls.Add(container);

        //Set sizes of inner controls
        TitelLabel.Size = new Size(Size.Width - 2, 20);
        ContentPanel.Size = new Size(Size.Width - 2, Size.Height - TitleHeight - 3);

        //Set anchor of inner controls
        TitelLabel.Anchor = AnchorStyles.Top | AnchorStyles.Left | AnchorStyles.Right;
        ContentPanel.Anchor = AnchorStyles.Top | AnchorStyles.Bottom | AnchorStyles.Left | AnchorStyles.Right;

        //Value defaults
        BackgroundColor = SystemColors.Window;
        BorderColor = SystemColors.GradientActiveCaption;
        TitleBackColor = Color.FromKnownColor(KnownColor.DodgerBlue);
        TitleFont = new Font("Calibri", TitleHeight - 9, FontStyle.Bold);
        TitleFontColor = SystemColors.Window;
        AllowDrop = true;

        //Set event handler
        ContentPanel.Resize += ContentPanelOnResize;
        ContentPanel.LocationChanged += ContentPanelOnLocationChanged;
    }

    private void ContentPanelOnLocationChanged(object sender, EventArgs eventArgs)
    {
        if (ContentPanel.Left != _contentPanelLeft | ContentPanel.Top != _contentPanelTop)
            ContentPanel.Location = new Point(_contentPanelLeft, _contentPanelTop);
    }

    private void ContentPanelOnResize(object sender, EventArgs eventArgs)
    {
        if (ContentPanel.Size.Width != _contentPanelWidth | ContentPanel.Size.Height != Size.Height - TitleHeight - 3)
            ContentPanel.Size = new Size(_contentPanelWidth, Size.Height - TitleHeight - 3);
    }

    //Make default property "BackColor" unvisible
    [Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public override Color BackColor { get; set; }

    //Use "BackgroundColor" instead of default "BackColor"
    /// <returns>The BackgroundColor associated with this control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("The backgroundcolor of the component.")]
    [Category("Appearance")]
    [DefaultValue(typeof(Color), "Window")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public Color BackgroundColor { get { return ContentPanel.BackColor; } set { ContentPanel.BackColor = value; } }

    /// <returns>The BorderColor associated with this control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the border color.")]
    [Category("Appearance")]
    [DefaultValue(typeof(Color), "GradientActiveCaption")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public Color BorderColor { get { return BackColor; } set { BackColor = value; } }

    /// <returns>The BorderColor of the title associated with this control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the title color.")]
    [Category("Appearance")]
    [DefaultValue(typeof(Color), "DodgerBlue")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public Color TitleBackColor { get { return TitelLabel.BackColor; } set { TitelLabel.BackColor = value; } }

    /// <returns>The height of the title associated with this control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the title height in px.")]
    [Category("Appearance")]
    [DefaultValue(typeof(int), "20")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public int TitleHeight
    {
        get { return TitelLabel.Size.Height; }
        set
        {
            TitelLabel.Size = new Size(TitelLabel.Size.Width, value);
            ContentPanel.Location = new Point(ContentPanel.Location.X, value + 2);
            ContentPanel.Size = new Size(ContentPanel.Size.Width, Size.Height - value - 3);
        }
    }

    /// <returns>The font of the title associated with this control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the title font.")]
    [Category("Appearance")]
    [DefaultValue(typeof(Font), "Calibri; 11pt; style=Bold")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public Font TitleFont { get { return TitelLabel.Font; } set { TitelLabel.Font = value; } }

    /// <returns>The ForeColor (color of the text) of the title associated with this control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the title font color.")]
    [Category("Appearance")]
    [DefaultValue(typeof(Color), "Window")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public Color TitleFontColor { get { return TitelLabel.ForeColor; } set { TitelLabel.ForeColor = value; } }

    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the title text.")]
    [Category("Appearance")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public override string Text { get { return TitelLabel.Text; } set { TitelLabel.Text = value; } }

    /// <returns>Sets the interior spacing in the control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the interior spacing in the control.")]
    [Category("Layout")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public new Padding Padding
    {
        get { return ContentPanel.Padding; }
        set { ContentPanel.Padding = value; }
    }

    /// <summary>Raises the <see cref="E:System.Windows.Forms.Control.Paint" /> event.</summary>
    /// <param name="e">A <see cref="T:System.Windows.Forms.PaintEventArgs" /> that contains the event data. </param>
    protected override void OnPaint(PaintEventArgs e)
    {
        base.OnPaint(e);

        if (!Focused || !Application.RenderWithVisualStyles) return;

        if (_renderer == null)
        {
            var elem = VisualStyleElement.Button.PushButton.Normal;
            _renderer = new VisualStyleRenderer(elem.ClassName, elem.Part, (int)PushButtonState.Normal);
        }

        var rc = _renderer.GetBackgroundContentRectangle(e.Graphics, new Rectangle(0, 0, Width, Height));
        rc.Height--;
        rc.Width--;

        using (var p = new Pen(Brushes.Purple))
        {
            e.Graphics.DrawRectangle(p, rc);
        }
    }
}

internal class BorderedGroupBoxDesigner : ControlDesigner
{
    private BorderedGroupBox borderedGroupBox;

    internal static SelectionRulesEnum SelectionRule;

    public override void Initialize(IComponent component)
    {
        base.Initialize(component);

        EnableDragDrop(true);

        borderedGroupBox = component as BorderedGroupBox;

        if (borderedGroupBox != null)
            EnableDesignMode(borderedGroupBox.ContentPanel, "Panel");
    }

    public override SelectionRules SelectionRules
    {
        get
        {
            switch (SelectionRule)
            {
                case SelectionRulesEnum.All:
                    return SelectionRules.Visible | SelectionRules.Moveable | SelectionRules.AllSizeable;
                case SelectionRulesEnum.UpDown:
                    return SelectionRules.Visible | SelectionRules.Moveable | SelectionRules.TopSizeable | SelectionRules.BottomSizeable;
                case SelectionRulesEnum.RightLeft:
                    return SelectionRules.Visible | SelectionRules.Moveable | SelectionRules.LeftSizeable | SelectionRules.RightSizeable;
                case SelectionRulesEnum.None:
                    return SelectionRules.Visible | SelectionRules.Moveable;
                default:
                    return SelectionRules.Visible | SelectionRules.Moveable;
            }
        }
    }

    internal enum SelectionRulesEnum
    {
        All,
        UpDown,
        RightLeft,
        None
    }
}

Sorry man, spent too much time on this, good luck, I cannot get the code to function on my end, your dynamic panel creation is my suspect of where your problem lies. — Trey, Mar 14 '17 at 15:32
No problem, if I had more spare time... anyhow good luck buddy. — Trey, Mar 14 '17 at 16:11
I have the solution! I'll post it as an answer. It was a bit tricky and I have had to remove several things... — Sven König, Mar 15 '17 at 07:02

Sven König · Accepted Answer · 2017-03-15T07:27:16.407

Here is the solution.

The problem was adding the controls to a child user control. So the solution is to add the controls directly to the user control it self and overriding the OnControlAdded event to bring the added control in front.

    protected override void OnControlAdded(ControlEventArgs e)
    {
        base.OnControlAdded(e);

        e.Control.BringToFront();
    }

Because if I add controls in design time, the designer showed the added control correctly as long as I don't build or rebuild.
At the moment I build/rebuild the form the designer tells the user control to add a control.

The user control added the control correctly but under the ContainerControl which contains the basic controls. => the control was no longer visible.

Here is the new code of the user control:

[Designer(typeof(BorderedGroupBoxDesigner))]
[DefaultEvent("Load")]
public sealed partial class BorderedGroupBox : UserControl
{
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    internal readonly Panel BackgroundPanel;

    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    internal readonly Label TitelLabel;

    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    internal new readonly ContainerControl Container;

    private VisualStyleRenderer _renderer;

    private int _contentPanelTop => TitleHeight + 2;

    private int _contentPanelLeft => 1;

    private int _contentPanelWidth => Size.Width - 2;

    private int _contentPanelHeight => Size.Height - TitleHeight;

    /// <summary>
    /// Initializes the Control.
    /// </summary>
    public BorderedGroupBox()
    {
        InitializeComponent();

        //Create TitleLabel
        if (TitelLabel == null)
            TitelLabel = new Label
            {
                Location = new Point(1, 1),
                AutoSize = false,
                TextAlign = ContentAlignment.MiddleLeft
            };

        //Create BackgroundPanel
        if (BackgroundPanel == null)
            BackgroundPanel = new Panel
            {
                Location = new Point(1, TitleHeight - 1)
            };

        //Create Container and add Panel
        if (Container == null)
            Container = new ContainerControl
            {
                Dock = DockStyle.Fill,
                Padding = new Padding(-1),
                Controls = { TitelLabel, BackgroundPanel }
            };

        //Add container and it's content to this control
        Controls.Add(Container);

        //Set sizes of inner controls
        TitelLabel.Size = new Size(Size.Width - 2, 20);
        BackgroundPanel.Size = new Size(Size.Width - 2, Size.Height - TitleHeight - 3);

        //Set anchor of inner controls
        TitelLabel.Anchor = AnchorStyles.Top | AnchorStyles.Left | AnchorStyles.Right;
        BackgroundPanel.Anchor = AnchorStyles.Top | AnchorStyles.Bottom | AnchorStyles.Left | AnchorStyles.Right;

        //Value defaults
        BackgroundColor = SystemColors.Window;
        BorderColor = SystemColors.GradientActiveCaption;
        TitleBackColor = Color.FromKnownColor(KnownColor.DodgerBlue);
        TitleFont = new Font("Calibri", TitleHeight - 9, FontStyle.Bold);
        TitleFontColor = SystemColors.Window;
        AllowDrop = true;
    }

    //Make default property "BackColor" unvisible
    [Browsable(false), EditorBrowsable(EditorBrowsableState.Never)]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public override Color BackColor { get; set; }

    //Use "BackgroundColor" instead of default "BackColor"
    /// <returns>The BackgroundColor associated with this control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("The backgroundcolor of the component.")]
    [Category("Appearance")]
    [DefaultValue(typeof(Color), "Window")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public Color BackgroundColor { get { return BackgroundPanel.BackColor; } set { BackgroundPanel.BackColor = value; } }

    /// <returns>The BorderColor associated with this control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the border color.")]
    [Category("Appearance")]
    [DefaultValue(typeof(Color), "GradientActiveCaption")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public Color BorderColor { get { return BackColor; } set { BackColor = value; } }

    /// <returns>The BorderColor of the title associated with this control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the title color.")]
    [Category("Appearance")]
    [DefaultValue(typeof(Color), "DodgerBlue")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public Color TitleBackColor { get { return TitelLabel.BackColor; } set { TitelLabel.BackColor = value; } }

    /// <returns>The height of the title associated with this control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the title height in px.")]
    [Category("Appearance")]
    [DefaultValue(typeof(int), "20")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public int TitleHeight
    {
        get { return TitelLabel.Size.Height; }
        set
        {
            TitelLabel.Size = new Size(TitelLabel.Size.Width, value);
            BackgroundPanel.Location = new Point(BackgroundPanel.Location.X, value + 2);
            BackgroundPanel.Size = new Size(BackgroundPanel.Size.Width, Size.Height - value - 3);
        }
    }

    /// <returns>The font of the title associated with this control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the title font.")]
    [Category("Appearance")]
    [DefaultValue(typeof(Font), "Calibri; 11pt; style=Bold")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public Font TitleFont { get { return TitelLabel.Font; } set { TitelLabel.Font = value; } }

    /// <returns>The ForeColor (color of the text) of the title associated with this control.</returns>
    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the title font color.")]
    [Category("Appearance")]
    [DefaultValue(typeof(Color), "Window")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public Color TitleFontColor { get { return TitelLabel.ForeColor; } set { TitelLabel.ForeColor = value; } }

    [Browsable(true), EditorBrowsable(EditorBrowsableState.Always)]
    [Description("Sets the title text.")]
    [Category("Appearance")]
    [DesignerSerializationVisibility(DesignerSerializationVisibility.Visible)]
    public override string Text { get { return TitelLabel.Text; } set { TitelLabel.Text = value; } }

    /// <summary>Raises the <see cref="E:System.Windows.Forms.Control.Paint" /> event.</summary>
    /// <param name="e">A <see cref="T:System.Windows.Forms.PaintEventArgs" /> that contains the event data. </param>
    protected override void OnPaint(PaintEventArgs e)
    {
        base.OnPaint(e);

        if (!Focused || !Application.RenderWithVisualStyles) return;

        if (_renderer == null)
        {
            var elem = VisualStyleElement.Button.PushButton.Normal;
            _renderer = new VisualStyleRenderer(elem.ClassName, elem.Part, (int)PushButtonState.Normal);
        }

        var rc = _renderer.GetBackgroundContentRectangle(e.Graphics, new Rectangle(0, 0, Width, Height));
        rc.Height--;
        rc.Width--;

        using (var p = new Pen(Brushes.Purple))
        {
            e.Graphics.DrawRectangle(p, rc);
        }
    }

    /// <summary>Raises the <see cref="E:System.Windows.Forms.Control.ControlAdded" /> event.</summary>
    /// <param name="e">A <see cref="T:System.Windows.Forms.ControlEventArgs" /> that contains the event data. </param>
    protected override void OnControlAdded(ControlEventArgs e)
    {
        base.OnControlAdded(e);

        e.Control.BringToFront();
    }
}

internal class BorderedGroupBoxDesigner : ParentControlDesigner
{
    internal static SelectionRulesEnum SelectionRule;

    public override void Initialize(IComponent component)
    {
        base.Initialize(component);

        EnableDragDrop(true);
    }

    public override SelectionRules SelectionRules
    {
        get
        {
            switch (SelectionRule)
            {
                case SelectionRulesEnum.All:
                    return SelectionRules.Visible | SelectionRules.Moveable | SelectionRules.AllSizeable;
                case SelectionRulesEnum.UpDown:
                    return SelectionRules.Visible | SelectionRules.Moveable | SelectionRules.TopSizeable | SelectionRules.BottomSizeable;
                case SelectionRulesEnum.RightLeft:
                    return SelectionRules.Visible | SelectionRules.Moveable | SelectionRules.LeftSizeable | SelectionRules.RightSizeable;
                case SelectionRulesEnum.None:
                    return SelectionRules.Visible | SelectionRules.Moveable;
                default:
                    return SelectionRules.Visible | SelectionRules.Moveable;
            }
        }
    }

    internal enum SelectionRulesEnum
    {
        All,
        UpDown,
        RightLeft,
        None
    }
}

C# updating usercontrol library will remove inner content

2 Answers2