🧱 Layout Controls

This document provides a comprehensive overview of all layout controls available in Atc.Wpf, including standard WPF panels/grids and custom controls provided by the library.

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📊 Quick Reference

🎯 Panel Comparison Table

Use this table to quickly identify which panel best suits your layout needs:

Panel	Library	Primary Use Case	Direction	Wrapping	Spacing	Proportional	Virtualized
Canvas	WPF	Absolute positioning	Absolute	❌ No	❌ No	❌ No	❌ No
DockPanel	WPF	Edge docking	Dock (TRBL)	❌ No	❌ No	❌ No	❌ No
DockPanelPro	Atc.Wpf	IDE-style resizable docking	Dock (TRBL)	❌ No	Via splitters	❌ No	❌ No
FlexPanel	Atc.Wpf	CSS Flexbox layouts	Row/Column + Reverse	✅ Yes	✅ Yes	✅ Yes (Grow/Shrink)	❌ No
Panel	WPF	Base class for custom panels	N/A	❌ No	❌ No	❌ No	❌ No
PanelEx	Atc.Wpf	Layered/overlay content	Overlay	❌ No	❌ No	❌ No	❌ No
ReversibleStackPanel	Atc.Wpf	Reversible stacking	Row/Column	❌ No	❌ No	❌ No	❌ No
ResponsivePanel	Atc.Wpf	Breakpoint-based responsive	Row	✅ Yes	✅ Yes	❌ No	❌ No
StackPanel	WPF	Simple stacking	Row/Column	❌ No	❌ No	❌ No	❌ No
StaggeredPanel	Atc.Wpf	Masonry/waterfall layout	Vertical columns	Auto	✅ Yes	❌ No	❌ No
UniformGrid	WPF	Equal-sized cells	Row/Column	❌ No	❌ No	✅ Yes	❌ No
UniformSpacingPanel	Atc.Wpf	Uniform spacing/wrapping	Row/Column	✅ Yes	✅ Yes	❌ No	❌ No
VirtualizingStaggeredPanel	Atc.Wpf	Large masonry collections	Vertical columns	Auto	✅ Yes	❌ No	✅ Yes
WrapPanel	WPF	Flowing wrap layout	Row/Column	✅ Yes	❌ No	❌ No	❌ No

🔲 Grid Comparison Table

Grid	Library	Primary Use Case	Auto Rows/Cols	String Definition	Responsive
AutoGrid	Atc.Wpf	Auto-indexed Grid	✅ Yes	✅ Yes	❌ No
Grid	WPF	Complex layouts	❌ Manual	❌ No	❌ No
GridEx	Atc.Wpf	Simplified Grid	❌ No	✅ Yes	❌ No
Row / Col	Atc.Wpf	Bootstrap-style responsive	✅ Yes	✅ Yes	✅ Yes

🎨 Container Controls

Control	Library	Primary Use Case	Collapsible	Theming
DockPanelPro	Atc.Wpf	IDE-style resizable docking	✅ Yes	✅ Yes
GridLines	Atc.Wpf	Debug grid visualization	❌ No	❌ No
GroupBoxExpander	Atc.Wpf	Collapsible grouped content	✅ Yes	✅ Yes

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🔍 When to Use Which Layout

Scenario	Best Choice	Why
Simple vertical/horizontal list	StackPanel	Lightweight, straightforward
Toolbar with proportional buttons	FlexPanel	Grow distributes space
Items that flow and wrap	UniformSpacingPanel	Consistent spacing + wrapping
Pinterest-style image gallery	StaggeredPanel	Optimal vertical space usage
Large image collection (1000+ items)	VirtualizingStaggeredPanel	Virtualization for performance
Complex form with rows/columns	Grid or AutoGrid	Precise cell positioning
Quick prototype grid	AutoGrid	Auto-indexing saves time
Responsive Bootstrap-style layout	Row / Col	Breakpoint-based columns
Responsive cards with visibility control	ResponsivePanel	Auto columns + hide/show at breakpoints
Navigation bar: logo left, menu right	FlexPanel	JustifyContent="SpaceBetween"
IDE-style resizable tool windows	DockPanelPro	Built-in splitters + collapse
Layered content / overlays	PanelEx	Children stack on top of each other
Custom panel implementation	Panel	Base class for custom layout logic
Collapsible settings section	GroupBoxExpander	Expand/collapse with header

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📦 Panels

📘 Canvas (WPF Built-in)

Description: Positions children using explicit coordinates (Left, Top, Right, Bottom).

When to Use:

• Drawing applications
• Diagram editors
• Absolute positioning requirements

Example:

<Canvas>
    <Rectangle Canvas.Left="50" Canvas.Top="30" Width="100" Height="50" Fill="Blue" />
    <Ellipse Canvas.Left="150" Canvas.Top="80" Width="60" Height="60" Fill="Red" />
</Canvas>

See Also: Microsoft Docs - Canvas

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📘 DockPanel (WPF Built-in)

Description: Positions children against the edges (Top, Bottom, Left, Right) with the last child filling remaining space.

When to Use:

• Application layouts with toolbars/status bars
• Sidebar + main content layouts

Example:

<DockPanel>
    <Menu DockPanel.Dock="Top"><!-- Menu items --></Menu>
    <StatusBar DockPanel.Dock="Bottom">Status</StatusBar>
    <TreeView DockPanel.Dock="Left" Width="200" />
    <ContentControl />  <!-- Fills remaining space -->
</DockPanel>

See Also: Microsoft Docs - DockPanel

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🟢 DockPanelPro

Location: Atc.Wpf.Controls.Layouts

Description: An enhanced dock panel with resizable splitters, collapsible regions, tabbed pane groups, floating tool windows and layout persistence. Perfect for building IDE-style interfaces with tool windows.

When to Use:

• IDE-style layouts with resizable tool windows
• Dashboard layouts with collapsible panels
• Applications requiring layout persistence
• Any layout needing user-adjustable regions

DockPanelPro Properties:

Property	Type	Default	Description
LayoutId	string	null	Identifier for layout persistence
AutoSaveLayout	bool	false	Automatically save layout changes
SplitterThickness	double	5	Thickness of resizable splitters
SplitterBackground	Brush	from theme	Background brush for splitters
AllowFloating	bool	false	Allow panes (DockPane) to float into their own tool windows

DockPanelPro Attached Properties:

Property	Type	Default	Description
DockPanelPro.Dock	DockPosition	Center	Left, Right, Top, Bottom, Center

DockRegion Properties:

Property	Type	Default	Description
RegionId	string	null	Unique identifier for persistence
IsCollapsible	bool	false	Enable collapse toggle button
IsExpanded	bool	true	Current expanded state
IsResizable	bool	true	Allow resizing via splitters
Header	object	null	Header content
MinWidth / MaxWidth	double	0 / ∞	Width constraints
MinHeight / MaxHeight	double	0 / ∞	Height constraints

Examples:

<!-- Example 1: IDE Layout -->
<layouts:DockPanelPro LayoutId="IDE" SplitterThickness="5">
    <layouts:DockRegion
        layouts:DockPanelPro.Dock="Left"
        Width="250"
        MinWidth="150"
        MaxWidth="400"
        Header="Explorer"
        IsCollapsible="True"
        RegionId="Explorer">
        <TreeView />
    </layouts:DockRegion>

    <layouts:DockRegion
        layouts:DockPanelPro.Dock="Bottom"
        Height="150"
        Header="Output"
        IsCollapsible="True"
        RegionId="Output">
        <TextBox IsReadOnly="True" />
    </layouts:DockRegion>

    <layouts:DockRegion layouts:DockPanelPro.Dock="Center" RegionId="Editor">
        <TabControl />
    </layouts:DockRegion>
</layouts:DockPanelPro>

<!-- Example 2: Dashboard with Navigation -->
<layouts:DockPanelPro>
    <layouts:DockRegion
        layouts:DockPanelPro.Dock="Left"
        Width="200"
        Header="Navigation"
        IsResizable="True">
        <StackPanel>
            <Button Content="Dashboard" />
            <Button Content="Reports" />
        </StackPanel>
    </layouts:DockRegion>

    <layouts:DockRegion layouts:DockPanelPro.Dock="Center" Header="Content">
        <ContentControl />
    </layouts:DockRegion>
</layouts:DockPanelPro>

Layout Persistence:

// Save layout
var layout = dockPanel.SaveLayout();
File.WriteAllText("layout.json", layout);

// Load layout
var layout = File.ReadAllText("layout.json");
dockPanel.LoadLayout(layout);

// Reset to defaults
dockPanel.ResetLayout();

Tabbed and floating panes: put DockPane elements in DockRegion.Panes to show them as tabs (with close buttons, Ctrl+Tab and a Float / Close menu); with AllowFloating="True" a pane floats into an owned, themed tool window and docks back to its previous position. SaveLayout (layout version 2) also stores the tabs, the active tab, closed and floating panes.

See Also: Full DockPanelPro Documentation

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🟢 FlexPanel

Location: Atc.Wpf.Controls.Layouts

Description: A CSS Flexbox-inspired layout panel supporting direction, justify-content, align-items, wrap, gap, and per-child grow/shrink/basis attached properties.

When to Use:

• Modern flexible layouts
• Toolbars with proportional sizing
• Navigation bars with space distribution
• Any layout requiring CSS Flexbox behavior

Properties:

Property	Type	Default	Description
Direction	FlexDirection	Row	Row, Column, RowReverse, ColumnReverse
JustifyContent	FlexJustify	Start	Start, End, Center, SpaceBetween, SpaceAround, SpaceEvenly
AlignItems	FlexAlign	Stretch	Stretch, Start, End, Center, Baseline
Wrap	FlexWrap	NoWrap	NoWrap, Wrap, WrapReverse
Gap	double	0	Spacing between items
RowGap	double	NaN	Vertical gap (overrides Gap)
ColumnGap	double	NaN	Horizontal gap (overrides Gap)

Attached Properties:

Property	Type	Default	Description
FlexPanel.Grow	double	0	How much the item should grow
FlexPanel.Shrink	double	1	How much the item should shrink
FlexPanel.Basis	double	NaN	Initial size before grow/shrink
FlexPanel.AlignSelf	FlexAlign	Auto	Override parent's AlignItems

Examples:

<!-- Example 1: Toolbar with spacer -->
<layouts:FlexPanel Direction="Row" AlignItems="Center" Gap="8">
    <Button Content="Save" />
    <Button Content="Load" />
    <!-- Items after this will be pushed to the right -->
    <Border layouts:FlexPanel.Grow="1" />
    <TextBlock Text="Status: Ready" />
</layouts:FlexPanel>

<!-- Example 2: Equal-width cards -->
<layouts:FlexPanel Direction="Row" Gap="16" Wrap="Wrap">
    <Border layouts:FlexPanel.Grow="1" layouts:FlexPanel.Basis="200" Background="LightBlue" Padding="16">
        <TextBlock Text="Card 1" />
    </Border>
    <Border layouts:FlexPanel.Grow="1" layouts:FlexPanel.Basis="200" Background="LightGreen" Padding="16">
        <TextBlock Text="Card 2" />
    </Border>
</layouts:FlexPanel>

<!-- Example 3: Navigation with space-between -->
<layouts:FlexPanel Direction="Row" JustifyContent="SpaceBetween" AlignItems="Center" Height="60">
    <Image Source="logo.png" Height="40" />
    <layouts:FlexPanel Direction="Row" Gap="16">
        <Button Content="Home" />
        <Button Content="About" />
    </layouts:FlexPanel>
</layouts:FlexPanel>

<!-- Example 4: Proportional sizing (1:2:1) -->
<layouts:FlexPanel Direction="Row" Gap="8">
    <Border layouts:FlexPanel.Grow="1" Background="#E3F2FD">
        <TextBlock Text="Sidebar (1x)" />
    </Border>
    <Border layouts:FlexPanel.Grow="2" Background="#BBDEFB">
        <TextBlock Text="Main (2x)" />
    </Border>
    <Border layouts:FlexPanel.Grow="1" Background="#E3F2FD">
        <TextBlock Text="Details (1x)" />
    </Border>
</layouts:FlexPanel>

<!-- Example 5: Centered form -->
<layouts:FlexPanel Direction="Column" AlignItems="Center" Gap="16">
    <TextBox Width="200" />
    <TextBox Width="200" />
    <Button Content="Submit" Width="120" />
</layouts:FlexPanel>

See Also: Full FlexPanel Documentation

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📘 Panel (WPF Built-in)

Description: The abstract base class for all WPF panel controls. Panel provides the framework for arranging child elements.

When to Use:

• Creating custom layout controls
• As a base class for specialized panels
• Understanding WPF layout fundamentals

Key Concepts:

• Override MeasureOverride(Size) to determine desired size
• Override ArrangeOverride(Size) to position children
• Access children via InternalChildren collection

Example:

public class SimpleOverlayPanel : Panel
{
    protected override Size MeasureOverride(Size availableSize)
    {
        var maxSize = new Size();
        foreach (UIElement child in InternalChildren)
        {
            child.Measure(availableSize);
            maxSize.Width = Math.Max(maxSize.Width, child.DesiredSize.Width);
            maxSize.Height = Math.Max(maxSize.Height, child.DesiredSize.Height);
        }
        return maxSize;
    }

    protected override Size ArrangeOverride(Size finalSize)
    {
        foreach (UIElement child in InternalChildren)
        {
            child.Arrange(new Rect(finalSize));
        }
        return finalSize;
    }
}

See Also: Microsoft Docs - Panel

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🟢 PanelEx

Location: Atc.Wpf.Controls.Layouts

Description: A simple panel that overlays all children on top of each other, sizing to the largest child. Similar to placing multiple items in the same Grid cell.

When to Use:

• Watermarks over content
• Loading overlays
• Badge/notification overlays
• Layered UI elements
• Any scenario requiring stacked content

Examples:

<!-- Example 1: Simple overlay -->
<atc:PanelEx Width="200" Height="150">
    <Border Background="LightBlue">
        <TextBlock Text="Background content" HorizontalAlignment="Center" VerticalAlignment="Center" />
    </Border>
    <TextBlock Text="NEW" HorizontalAlignment="Right" VerticalAlignment="Top"
               Foreground="Red" FontWeight="Bold" Margin="5" />
</atc:PanelEx>

<!-- Example 2: Watermark -->
<atc:PanelEx>
    <Border Background="White" BorderBrush="Gray" BorderThickness="1" Padding="16">
        <TextBlock Text="Document content..." />
    </Border>
    <TextBlock Text="DRAFT" HorizontalAlignment="Center" VerticalAlignment="Center"
               FontSize="48" Foreground="#20000000" FontWeight="Bold" />
</atc:PanelEx>

<!-- Example 3: Loading overlay -->
<atc:PanelEx>
    <Border Background="White">
        <StackPanel>
            <TextBlock Text="Your content here" />
        </StackPanel>
    </Border>
    <Border Background="#80000000" Visibility="{Binding IsLoading, Converter={StaticResource BoolToVisibility}}">
        <StackPanel HorizontalAlignment="Center" VerticalAlignment="Center">
            <TextBlock Text="Loading..." Foreground="White" />
        </StackPanel>
    </Border>
</atc:PanelEx>

<!-- Example 4: Corner badge -->
<atc:PanelEx Width="100" Height="100">
    <Border Background="LightGreen" CornerRadius="8">
        <TextBlock Text="Product" HorizontalAlignment="Center" VerticalAlignment="Center" />
    </Border>
    <Border Width="24" Height="24" Background="Orange" CornerRadius="12"
            HorizontalAlignment="Right" VerticalAlignment="Top" Margin="-8,-8,0,0">
        <TextBlock Text="5" HorizontalAlignment="Center" VerticalAlignment="Center"
                   Foreground="White" FontWeight="Bold" FontSize="10" />
    </Border>
</atc:PanelEx>

---

🟢 ReversibleStackPanel

Location: Atc.Wpf.Controls.Layouts

Description: A StackPanel with the ability to reverse the order of children.

When to Use:

• Chat messages (newest at bottom vs top)
• Reversible lists
• RTL layouts

Properties:

Property	Type	Default	Description
ReverseOrder	bool	false	Whether to reverse children order
Orientation	Orientation	Vertical	Inherited from StackPanel

Examples:

<!-- Example 1: Reversed vertical stack -->
<layouts:ReversibleStackPanel Orientation="Vertical" ReverseOrder="True">
    <TextBlock Text="First (appears last)" />
    <TextBlock Text="Second" />
    <TextBlock Text="Third (appears first)" />
</layouts:ReversibleStackPanel>

<!-- Example 2: Chat messages (newest at bottom) -->
<layouts:ReversibleStackPanel
    Orientation="Vertical"
    ReverseOrder="{Binding ShowNewestFirst}">
    <TextBlock Text="Message 1" />
    <TextBlock Text="Message 2" />
    <TextBlock Text="Message 3" />
</layouts:ReversibleStackPanel>

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🟢 ResponsivePanel

Location: Atc.Wpf.Controls.Layouts

Description: A responsive layout panel that adapts its column count based on available width using configurable breakpoints. Supports auto-calculated columns, explicit column counts per breakpoint, visibility control, and item reordering.

When to Use:

• Responsive card/tile layouts
• Dashboards that adapt to screen size
• Layouts requiring visibility control at breakpoints
• Mobile-first or desktop-first responsive designs

Breakpoints:

Breakpoint	Width Range	Typical Device
Xs	< 576px	Small phones
Sm	576px - 767px	Phones, small tablets
Md	768px - 991px	Tablets
Lg	992px - 1199px	Small laptops
Xl	>= 1200px	Desktops, large screens

Properties:

Property	Type	Default	Description
Gap	double	0	Uniform gap between items
RowGap	double	NaN	Vertical gap (overrides Gap)
ColumnGap	double	NaN	Horizontal gap (overrides Gap)
MinItemWidth	double	NaN	Auto-calculate columns from this width
ColumnsXs	int	1	Columns at XS breakpoint
ColumnsSm	int	2	Columns at SM breakpoint
ColumnsMd	int	3	Columns at MD breakpoint
ColumnsLg	int	4	Columns at LG breakpoint
ColumnsXl	int	6	Columns at XL breakpoint

Attached Properties:

Property	Type	Description
SpanXs/Sm/Md/Lg/Xl	int	Column span at each breakpoint
VisibleFrom	ResponsiveBreakpoint?	Show at this breakpoint and larger
HiddenFrom	ResponsiveBreakpoint?	Hide at this breakpoint and larger
OrderXs/Sm/Md/Lg/Xl	int	Display order at each breakpoint

Examples:

<!-- Example 1: Auto column count -->
<layouts:ResponsivePanel MinItemWidth="280" Gap="16">
    <Border Background="LightBlue" Height="100" />
    <Border Background="LightGreen" Height="100" />
    <Border Background="LightCoral" Height="100" />
</layouts:ResponsivePanel>

<!-- Example 2: Explicit column counts -->
<layouts:ResponsivePanel
    ColumnsXs="1"
    ColumnsSm="2"
    ColumnsMd="3"
    ColumnsLg="4"
    Gap="16">
    <Border Background="LightBlue" />
    <Border Background="LightGreen" />
</layouts:ResponsivePanel>

<!-- Example 3: 12-column grid with spans -->
<layouts:ResponsivePanel
    ColumnsLg="12"
    ColumnsMd="12"
    Gap="16">
    <Border
        layouts:ResponsivePanel.SpanLg="4"
        layouts:ResponsivePanel.SpanMd="12"
        Background="LightBlue">
        <TextBlock Text="Sidebar" />
    </Border>
    <Border
        layouts:ResponsivePanel.SpanLg="8"
        layouts:ResponsivePanel.SpanMd="12"
        Background="LightGreen">
        <TextBlock Text="Main Content" />
    </Border>
</layouts:ResponsivePanel>

<!-- Example 4: Visibility control -->
<layouts:ResponsivePanel ColumnsLg="4" Gap="16">
    <Border Background="LightBlue" />
    <Border layouts:ResponsivePanel.VisibleFrom="Lg" Background="LightGreen" />
    <Border layouts:ResponsivePanel.HiddenFrom="Md" Background="LightCoral" />
</layouts:ResponsivePanel>

See Also: Full ResponsivePanel Documentation

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📘 StackPanel (WPF Built-in)

Description: Arranges children in a single line (horizontal or vertical).

When to Use:

• Simple lists of items
• Vertical forms
• Horizontal toolbars without proportional sizing

Example:

<StackPanel Orientation="Vertical">
    <TextBlock Text="Item 1" />
    <TextBlock Text="Item 2" />
    <TextBlock Text="Item 3" />
</StackPanel>

See Also: Microsoft Docs - StackPanel

---

🟢 StaggeredPanel

Location: Atc.Wpf.Controls.Layouts

Description: A masonry/waterfall layout panel that places items in the column with the least height, creating a Pinterest-style effect.

When to Use:

• Image galleries with varying heights
• Card layouts with different content sizes
• Pinterest-style layouts
• Small to medium collections (use VirtualizingStaggeredPanel for large collections)

Properties:

Property	Type	Default	Description
DesiredItemWidth	double	250	Desired column width
Padding	Thickness	0	Inner padding
HorizontalSpacing	double	0	Gap between columns
VerticalSpacing	double	0	Gap between items

Examples:

<!-- Example 1: Basic masonry layout -->
<layouts:StaggeredPanel DesiredItemWidth="200" HorizontalSpacing="10" VerticalSpacing="10">
    <Border Height="150" Background="Red" />
    <Border Height="200" Background="Green" />
    <Border Height="120" Background="Blue" />
    <Border Height="180" Background="Yellow" />
</layouts:StaggeredPanel>

<!-- Example 2: Image gallery -->
<layouts:StaggeredPanel DesiredItemWidth="250" HorizontalSpacing="12" VerticalSpacing="12" Padding="16">
    <Image Source="photo1.jpg" />
    <Image Source="photo2.jpg" />
    <Image Source="photo3.jpg" />
</layouts:StaggeredPanel>

<!-- Example 3: Card gallery in ItemsControl -->
<ItemsControl ItemsSource="{Binding Items}">
    <ItemsControl.ItemsPanel>
        <ItemsPanelTemplate>
            <layouts:StaggeredPanel DesiredItemWidth="280" HorizontalSpacing="16" VerticalSpacing="16" />
        </ItemsPanelTemplate>
    </ItemsControl.ItemsPanel>
    <ItemsControl.ItemTemplate>
        <DataTemplate>
            <layouts:Card Header="{Binding Title}">
                <TextBlock Text="{Binding Description}" TextWrapping="Wrap" />
            </layouts:Card>
        </DataTemplate>
    </ItemsControl.ItemTemplate>
</ItemsControl>

See Also: Full StaggeredPanel Documentation

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📘 UniformGrid (WPF Built-in)

Description: Arranges children in a grid where all cells are the same size.

When to Use:

• Calculator buttons
• Game boards
• Equally-sized item grids

Example:

<UniformGrid Rows="3" Columns="3">
    <Button Content="1" />
    <Button Content="2" />
    <Button Content="3" />
    <Button Content="4" />
    <Button Content="5" />
    <Button Content="6" />
    <Button Content="7" />
    <Button Content="8" />
    <Button Content="9" />
</UniformGrid>

See Also: Microsoft Docs - UniformGrid

---

🟢 UniformSpacingPanel

Location: Atc.Wpf.Controls.Layouts

Description: A panel that provides uniform spacing between items with optional wrapping support.

When to Use:

• Tag/chip lists with consistent spacing
• Button groups
• Any wrapping content with uniform gaps

Properties:

Property	Type	Default	Description
Orientation	Orientation	Horizontal	Horizontal or Vertical
ChildWrapping	VisualWrappingType	None	None, Wrap, WrapReverse
Spacing	double	NaN	Uniform spacing between items
HorizontalSpacing	double	NaN	Horizontal spacing (overrides Spacing)
VerticalSpacing	double	NaN	Vertical spacing (overrides Spacing)
ItemWidth	double	NaN	Fixed width for all items
ItemHeight	double	NaN	Fixed height for all items
ItemHorizontalAlignment	HorizontalAlignment?	Stretch	Child horizontal alignment
ItemVerticalAlignment	VerticalAlignment?	Stretch	Child vertical alignment

Examples:

<!-- Example 1: Button group with spacing -->
<layouts:UniformSpacingPanel Orientation="Horizontal" Spacing="8">
    <Button Content="Save" />
    <Button Content="Cancel" />
    <Button Content="Help" />
</layouts:UniformSpacingPanel>

<!-- Example 2: Wrapping tags -->
<layouts:UniformSpacingPanel
    Orientation="Horizontal"
    ChildWrapping="Wrap"
    HorizontalSpacing="8"
    VerticalSpacing="8">
    <layouts:Chip Content="C#" />
    <layouts:Chip Content="WPF" />
    <layouts:Chip Content="MVVM" />
    <layouts:Chip Content=".NET" />
</layouts:UniformSpacingPanel>

<!-- Example 3: Vertical list with spacing -->
<layouts:UniformSpacingPanel Orientation="Vertical" Spacing="12">
    <TextBox PlaceholderText="Name" />
    <TextBox PlaceholderText="Email" />
    <TextBox PlaceholderText="Message" />
</layouts:UniformSpacingPanel>

See Also: Full UniformSpacingPanel Documentation

---

🟢 VirtualizingStaggeredPanel

Location: Atc.Wpf.Controls.Layouts

Description: A virtualized version of StaggeredPanel for large collections (hundreds or thousands of items).

When to Use:

• Large image galleries
• Infinite scroll implementations
• Any masonry layout with 100+ items

Properties: Same as StaggeredPanel.

Example:

<ListBox ItemsSource="{Binding LargeCollection}">
    <ListBox.ItemsPanel>
        <ItemsPanelTemplate>
            <layouts:VirtualizingStaggeredPanel
                DesiredItemWidth="200"
                HorizontalSpacing="8"
                VerticalSpacing="8" />
        </ItemsPanelTemplate>
    </ListBox.ItemsPanel>
</ListBox>

---

📘 WrapPanel (WPF Built-in)

Description: Positions children sequentially, wrapping to the next line when space runs out.

When to Use:

• Tag clouds
• Photo thumbnails
• Any content that should flow and wrap

Example:

<WrapPanel Orientation="Horizontal">
    <Button Content="Tag 1" Margin="4" />
    <Button Content="Tag 2" Margin="4" />
    <Button Content="Tag 3" Margin="4" />
    <!-- Wraps automatically -->
</WrapPanel>

See Also: Microsoft Docs - WrapPanel

---

🔲 Grids

🟢 AutoGrid

Location: Atc.Wpf.Controls.Layouts

Description: A Grid that automatically positions children based on their index, eliminating the need for Grid.Row/Grid.Column on each child.

When to Use:

• Quick form layouts
• Reducing repetitive Grid.Row/Grid.Column assignments
• Prototyping

Properties:

Property	Type	Description
Rows	string	Comma-separated row definitions
Columns	string	Comma-separated column definitions
RowCount	int	Number of rows (default: 1)
ColumnCount	int	Number of columns (default: 1)
RowHeight	GridLength	Default height for auto-generated rows
ColumnWidth	GridLength	Default width for auto-generated columns
Orientation	Orientation	Fill direction (Horizontal or Vertical)
IsAutoIndexing	bool	Enable auto-positioning (default: true)
ChildMargin	Thickness?	Margin applied to all children
ChildHorizontalAlignment	HorizontalAlignment?	Alignment for all children
ChildVerticalAlignment	VerticalAlignment?	Alignment for all children

Examples:

<!-- Example 1: Simple form (2 columns, auto rows) -->
<layouts:AutoGrid Columns="Auto,*" ChildMargin="4">
    <TextBlock Text="Name:" />
    <TextBox />

    <TextBlock Text="Email:" />
    <TextBox />

    <TextBlock Text="Phone:" />
    <TextBox />
</layouts:AutoGrid>

<!-- Example 2: Button grid (3 columns) -->
<layouts:AutoGrid Columns="*,*,*" RowHeight="40" ChildMargin="4">
    <Button Content="1" />
    <Button Content="2" />
    <Button Content="3" />
    <Button Content="4" />
    <Button Content="5" />
    <Button Content="6" />
</layouts:AutoGrid>

<!-- Example 3: Vertical fill -->
<layouts:AutoGrid Rows="*,*,*" Orientation="Vertical">
    <TextBlock Text="Row 0" />
    <TextBlock Text="Row 1" />
    <TextBlock Text="Row 2" />
</layouts:AutoGrid>

<!-- Example 4: Fixed row/column counts -->
<layouts:AutoGrid RowCount="3" ColumnCount="4" RowHeight="50" ColumnWidth="100">
    <!-- 12 cells will be created -->
</layouts:AutoGrid>

See Also: Full AutoGrid Documentation

---

📘 Grid (WPF Built-in)

Description: The standard WPF Grid with explicit row/column definitions.

When to Use:

• Complex form layouts
• Precise control over cell positioning
• Layouts requiring row/column spanning

Example:

<Grid>
    <Grid.RowDefinitions>
        <RowDefinition Height="Auto" />
        <RowDefinition Height="*" />
        <RowDefinition Height="Auto" />
    </Grid.RowDefinitions>
    <Grid.ColumnDefinitions>
        <ColumnDefinition Width="200" />
        <ColumnDefinition Width="*" />
    </Grid.ColumnDefinitions>

    <TextBlock Grid.Row="0" Grid.Column="0" Text="Label" />
    <TextBox Grid.Row="0" Grid.Column="1" />
</Grid>

See Also: Microsoft Docs - Grid

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🟢 GridEx

Location: Atc.Wpf.Controls.Layouts

Description: An enhanced Grid that supports string-based row and column definitions for cleaner XAML.

When to Use:

• Simplifying Grid definitions
• Quick prototyping
• Reducing XAML verbosity

Properties:

Property	Type	Description
Rows	string	Comma-separated row definitions (e.g., "Auto,,2,100")
Columns	string	Comma-separated column definitions (e.g., "200,*,Auto")

Examples:

<!-- Example 1: Simple 3x3 grid -->
<layouts:GridEx Rows="*,*,*" Columns="*,*,*">
    <TextBlock Grid.Row="0" Grid.Column="0" Text="[0,0]" />
    <TextBlock Grid.Row="1" Grid.Column="1" Text="[1,1]" />
</layouts:GridEx>

<!-- Example 2: Form layout -->
<layouts:GridEx Rows="Auto,Auto,Auto,*" Columns="Auto,*">
    <TextBlock Grid.Row="0" Grid.Column="0" Text="Name:" />
    <TextBox Grid.Row="0" Grid.Column="1" />

    <TextBlock Grid.Row="1" Grid.Column="0" Text="Email:" />
    <TextBox Grid.Row="1" Grid.Column="1" />

    <TextBlock Grid.Row="2" Grid.Column="0" Text="Notes:" />
    <TextBox Grid.Row="2" Grid.Column="1" />
</layouts:GridEx>

<!-- Example 3: Proportional sizing -->
<layouts:GridEx Rows="2*,1*,1*" Columns="2*,1*,1*">
    <!-- Cell [0,0] is double the size of cell [2,2] -->
</layouts:GridEx>

<!-- Example 4: Mixed sizing -->
<layouts:GridEx Rows="Auto,*,66" Columns="200,*,Auto">
    <!-- Row 0: Auto-sized, Row 1: fills remaining, Row 2: 66px -->
    <!-- Col 0: 200px, Col 1: fills remaining, Col 2: Auto-sized -->
</layouts:GridEx>

See Also: Full GridEx Documentation

---

🟢 Row / Col

Location: Atc.Wpf.Controls.Layouts.Grid

Description: Bootstrap-style responsive grid system with breakpoint-based column spanning.

When to Use:

• Responsive layouts
• Bootstrap-familiar developers
• Layouts that adapt to window size

Col Properties:

Property	Type	Description
Span	ColLayout	Column span at default breakpoint
Xs	ColLayout	Column span at extra-small breakpoint
Sm	ColLayout	Column span at small breakpoint
Md	ColLayout	Column span at medium breakpoint
Lg	ColLayout	Column span at large breakpoint
Xl	ColLayout	Column span at extra-large breakpoint
Xxl	ColLayout	Column span at extra-extra-large breakpoint

Examples:

<!-- Example 1: Basic responsive columns -->
<layouts:Row>
    <layouts:Col Span="12" Md="6" Lg="4">
        <Border Background="LightBlue" Padding="16">
            <TextBlock Text="Column 1" />
        </Border>
    </layouts:Col>
    <layouts:Col Span="12" Md="6" Lg="4">
        <Border Background="LightGreen" Padding="16">
            <TextBlock Text="Column 2" />
        </Border>
    </layouts:Col>
    <layouts:Col Span="12" Md="12" Lg="4">
        <Border Background="LightCoral" Padding="16">
            <TextBlock Text="Column 3" />
        </Border>
    </layouts:Col>
</layouts:Row>

<!-- Example 2: Sidebar + Main content -->
<layouts:Row>
    <layouts:Col Span="12" Lg="3">
        <Border Background="#E3F2FD" Padding="16">
            <TextBlock Text="Sidebar" />
        </Border>
    </layouts:Col>
    <layouts:Col Span="12" Lg="9">
        <Border Background="#BBDEFB" Padding="16">
            <TextBlock Text="Main Content" />
        </Border>
    </layouts:Col>
</layouts:Row>

---

🎨 Container Controls

🟢 GridLines

Location: Atc.Wpf.Controls.Layouts

Description: A debugging control that displays grid lines for layout visualization.

When to Use:

• Debugging layouts
• Visualizing grid structure
• Design-time assistance

---

🟢 GroupBoxExpander

Location: Atc.Wpf.Controls.Layouts

Description: A collapsible GroupBox with expand/collapse toggle button.

When to Use:

• Collapsible settings sections
• Form sections that can be hidden
• Space-saving UI patterns

Properties:

Property	Type	Default	Description
Header	object	-	Header content (inherited)
IsExpanded	bool	true	Current expanded state
ExpanderButtonLocation	ExpanderButtonLocation	Left	Toggle button position
CornerRadius	CornerRadius	-	Corner rounding
HeaderBackground	Brush	-	Header background color
HeaderForeground	Brush	-	Header text color
HeaderPadding	Thickness	4	Header inner padding

Events:

Event	Description
Expanded	Raised when the control expands
Collapsed	Raised when the control collapses

Examples:

<!-- Example 1: Basic collapsible section -->
<layouts:GroupBoxExpander Header="Optional Settings" IsExpanded="False">
    <StackPanel>
        <CheckBox Content="Enable feature A" />
        <CheckBox Content="Enable feature B" />
    </StackPanel>
</layouts:GroupBoxExpander>

<!-- Example 2: Right-aligned toggle -->
<layouts:GroupBoxExpander
    Header="Advanced"
    ExpanderButtonLocation="Right"
    HeaderBackground="#F5F5F5">
    <TextBox PlaceholderText="Advanced configuration..." />
</layouts:GroupBoxExpander>

---

📚 Summary

Category	Count	Key Controls
📦 Panels	14	FlexPanel, PanelEx, ResponsivePanel, StaggeredPanel, UniformSpacingPanel
🔲 Grids	4	AutoGrid, GridEx, Row/Col
🎨 Containers	3	DockPanelPro, GridLines, GroupBoxExpander

See also: Data Display Controls for Avatar, Badge, Card, Chip, and Divider controls.

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📅 Last Updated: January 2026 🤖 Generated with Claude Code