按文本内容自动调整面板

Question

I have a WinForms-Application where I want to add UserControls dynamicly docking to the top:

this.Controls.Clear();
this.Controls.Add(myCustomControl(){Title="first", content="first text", Dock=DockStyle.Top});
this.Controls.Add(myCustomControl(){Title="second", content="very long text, where......", Dock=DockStyle.Top});

now myCostumControl [YELLOW] is a userControl with the following content:

TopTitle [PINK]: A Label, docked to the top
BottomContent [GREEN]: A Panel, Fills out the rest of the Control below the TopTitle (Dockstyle Fill)
TextContent [BLUE]: A multiline Textbox, docked (fill) within the Panel.

So it looks like this:

Now what I need to achieve is that the Height from myCustomControl is according to the Text-Content of the "TextContent" - TextBox, so I can stack multiple Controls. So if there is only a "Hello World" in it, the height should be small, if I put the Windows EULA in it it should be very long.

I already tried messing around with all "AutoSize"-properties I could get my hands on, but the Textbox either disappeared completely or it hat no effect.

I also tried resizing the Textbox on Change:

Size size = TextRenderer.MeasureText(txtContent.Text, txtContent.Font);
txtContent.Height = size.Height; 

No success, either

Answer 1

To make your composite control auto-size, perform these settings:

• Add a Label to user control and set AutoSize of label to false and set it's height to a suitable height and set its Dock to top.
• Add a TextBox to user control and set its Dock to Fill .

• override SetBoundsCore and calculate the preferred size of control:

   protected override void SetBoundsCore(int x, int y, int width, int height, BoundsSpecified specified) { var flags = TextFormatFlags.WordBreak | TextFormatFlags.NoPrefix; var proposedSize = new Size(width, int.MaxValue); var size = TextRenderer.MeasureText(textBox1.Text, textBox1.Font, proposedSize, flags); height = Math.Max(size.Height, textBox1.Font.Height) + label1.Height + 5; base.SetBoundsCore(x, y, width, height, specified); }

• Handle TextChanged event of the TextBox to refresh size of control when content text changes:

   void textBox1_TextChanged(object sender, EventArgs e) { SetBoundsCore(Left, Top, Width, Height, BoundsSpecified.Size); }

Here is the result:

Answer 2

If you want myCustomControl to be autosized, then obvioulsy, you cannot use fill docking for any child controls as docking set the size of the child according to parent size and you want parent size to adjust according to child size.

So you should either use a table layout or a flow layout for the child. If you use a table, then, you have to use auto-size for the rows that should adapt.

Then the whole layout control could be set to auto-size and should be docked at top (or maybe anchored).

An you can the parent to display a vertical scrollbar if the layout control does not fit in visible area.