Move a rendering

gistfile1.cs

// Move renderings example usage
var rendering = device.Renderings.Cast<RenderingDefinition>().SingleOrDefault(r => r.ItemID == MyRenderingId);
device.MoveRenderingUp(rendering);
item[Sitecore.FieldIDs.LayoutField] = layoutDefinition.ToXml();

// DeviceDefinition Extensions
public static class DeviceDefinitionExtensions
{
	public static void MoveRenderingDown(this DeviceDefinition deviceDefinition, RenderingDefinition renderingDefinition)
	{
		Sitecore.Diagnostics.Assert.IsNotNull(renderingDefinition, "renderingDefinition cannot be null");
		Sitecore.Diagnostics.Assert.IsNotNull(deviceDefinition.Renderings, "device renderings cannot be null");

		var index = deviceDefinition.Renderings.IndexOf(renderingDefinition);
		bool isIndexValid = index == deviceDefinition.Renderings.Count - 1;
		Sitecore.Diagnostics.Assert.IsTrue(isIndexValid, "renderingDefinition is at the last position. Cannot be moved.");

		deviceDefinition.MoveRendering(renderingDefinition, index + 1);
	}

	public static void MoveRenderingUp(this DeviceDefinition deviceDefinition, RenderingDefinition renderingDefinition)
	{
		Sitecore.Diagnostics.Assert.IsNotNull(renderingDefinition, "renderingDefinition cannot be null");
		Sitecore.Diagnostics.Assert.IsNotNull(deviceDefinition.Renderings, "device renderings cannot be null");

		var index = deviceDefinition.Renderings.IndexOf(renderingDefinition);
		Sitecore.Diagnostics.Assert.IsTrue(index != 0, "renderingDefinition is at the first position. Cannot be moved.");

		deviceDefinition.MoveRendering(renderingDefinition, index - 1);
	}
		
	public static void MoveRendering(this DeviceDefinition deviceDefinition, RenderingDefinition renderingDefinition, int position)
	{
		Sitecore.Diagnostics.Assert.IsNotNull(renderingDefinition, "renderingDefinition cannot be null");
		Sitecore.Diagnostics.Assert.IsNotNull(deviceDefinition.Renderings, "device renderings cannot be null");

		bool isPositionValid = position >= 0 && position < deviceDefinition.Renderings.Count;
		Sitecore.Diagnostics.Assert.IsTrue(isPositionValid, "position is outside the bounds of the rendering collection");

		var index = deviceDefinition.Renderings.IndexOf(renderingDefinition);
		Sitecore.Diagnostics.Assert.IsTrue(index >= 0, "renderingDefinition does not exist in the redering collection of the specified device");

		deviceDefinition.Renderings.Remove(renderingDefinition);
		deviceDefinition.Renderings.Insert(position, renderingDefinition);
	}
}