multi_split_view

Use the MultiSplitViewTheme widget to apply a specific MultiSplitViewThemeData configuration to all descendant MultiSplitView widgets in the widget tree. This allows you to centralize styling and behavior settings for your split views.

To use it, wrap your widget tree (or a specific subtree) with MultiSplitViewTheme and provide a data object of type MultiSplitViewThemeData.

MultiSplitViewTheme(
  data: MultiSplitViewThemeData(
    // Configure your theme properties here
  ),
  child: YourSplitViewWidget(),
)

Use MultiSplitViewThemeData to define the visual configuration for a MultiSplitView widget subtree. This allows you to control the thickness of the dividers, the clickable area around them, and the painter used to draw the dividers.

Properties

• dividerThickness: A double representing the thickness of the divider. Must be a non-negative value. Defaults to 10.0.
• dividerHandleBuffer: A double defining the additional clickable area around the divider. Must be a non-negative value. Defaults to 0.0.
• dividerPainter: An optional DividerPainter used to customize how the divider is drawn.

Constraints

Both dividerThickness and dividerHandleBuffer must be non-negative. Providing a negative value will throw an ArgumentError.

MultiSplitViewThemeData( 
  dividerThickness: 5.0, 
  dividerHandleBuffer: 2.0, 
  dividerPainter: MyCustomPainter(),
);

The MultiSplitViewController is used to programmatically control and manage the state of a MultiSplitView. It allows you to add, remove, and access Area objects that define the split layout.

Important: Do not share a single MultiSplitViewController instance between multiple MultiSplitView widgets.

// Initialize the controller with an initial list of areas
final controller = MultiSplitViewController(areas: [
  Area(flex: 1),
  Area(flex: 2),
]);

// Access the current areas
List<Area> currentAreas = controller.areas;

// Get the count of areas
int count = controller.areasCount;

The AreaDataModifier is a typedef for a function that allows you to automatically set or modify the data attribute of an Area based on its current state and index. This is useful for injecting custom metadata into areas during layout updates.

typedef AreaDataModifier = dynamic Function(Area area, int index);

You can assign this modifier to the areaDataModifier property of the MultiSplitViewController.

// Define a modifier that assigns custom data to each area
MultiSplitViewController controller = MultiSplitViewController(
  areaDataModifier: (Area area, int index) {
    return {'id': 'area_$index', 'custom_prop': 'value'};
  },
);

// You can also update the modifier later
controller.areaDataModifier = (area, index) => {'index': index};

To retrieve the current theme configuration from the nearest MultiSplitViewTheme ancestor, use the static MultiSplitViewTheme.of(BuildContext context) method.

If no MultiSplitViewTheme is found in the context, it returns a default MultiSplitViewThemeData instance.

MultiSplitViewThemeData currentTheme = MultiSplitViewTheme.of(context);

Use the copyWith method to create a new Area instance based on an existing one, replacing specific fields while keeping the rest unchanged. This is useful for immutable-style updates or generating variations of a layout configuration.

Area newArea = existingArea.copyWith(
  size: 400.0,
  data: 'new data',
);

You can dynamically modify the layout of a MultiSplitView using the following methods on the MultiSplitViewController:

• addArea(Area area): Adds a new Area to the split view.
• removeAreaAt(int index): Removes the Area at the specified index.
• getArea(int index): Retrieves the Area object at the given index.
• set areas(List<Area> areas): Replaces the entire set of areas with a new list.

// Add a new area
controller.addArea(Area(flex: 1));

// Remove an area at a specific index
controller.removeAreaAt(0);

// Replace all areas
controller.areas = [
  Area(flex: 1),
  Area(flex: 1),
];

The Area class extends ChangeNotifier, allowing you to dynamically update its dimensions. When you update size, flex, min, or max, the area notifies its listeners to trigger a rebuild.

Important Rules:

• Setting size while flex is non-null (or vice versa) will throw an ArgumentError.
• Setting min or max values that result in max < min will throw an ArgumentError.

// Example of dynamic updates
void resizeArea(Area area) {
  area.size = 300.0; // Updates size and notifies listeners
  area.flex = 1.0;  // Updates flex and notifies listeners
}