NShape Basic Tutorial

Basic Tutorial: Layout

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NShape Basic Tutorial

Basic Tutorial: Layout

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In this step you will learn how to apply an automatic layout to a diagram.

In order to get a presentable diagram a reasonable layout of the shapes is required. This can be achieved using the NShape layouter classes. There are different layouters in NShape for different kinds of diagrams, for example a grid layouter, which positions the shapes in a regular grid, a repulsion layouter, which uses an algorithm of repulsive forces to distribute the shapes, and others.

All layouters have the same basic usage schema:

1.Add the namespace Dataweb.NShape.Layouters.

2.Create a layouter of the desired class.

3.Assign the shapes that shall be layouted.

4.Set the parameters for the layout.

5.Execute the layouting.

In the WebVisits example you have to do the following:

How to use a layouter to arrange the shapes of the diagram:

1.Add a menu item File > Layout and create a handler for it.

2.In the handler first move all shapes to the same position. This is the start configuration for which the repulsion layouter works best.

3.Then create and execute the layouter as described before.

4.Finally, use the layouters Fit method to center the diagram on the page.

5.Run the application, load the web stats and then run the layout.

Layout

Automatic layouting is a complex subject and usually you will need to run more than one layouter to get a good result. And a perfect result will always require some manual adjustment. Read the layouting topics in the tasks section of the online help to learn more about it.

Here is the code:

// First, place all shapes to the same position
foreach (Shape s in display1.Diagram.Shapes) {
 s.X = 100;
 s.Y = 100;
}
// Create the layouter and set up layout parameters
RepulsionLayouter layouter = new RepulsionLayouter(project1);
// Set the repulsion force and its range
layouter.SpringRate = 8;
layouter.Repulsion = 3;
layouter.RepulsionRange = 500;
// Set the friction and the mass of the shapes
layouter.Friction = 0;
layouter.Mass = 50;
// Set all shapes 
layouter.AllShapes = display1.Diagram.Shapes;
// Set shapes that should be layouted
layouter.Shapes = display1.Diagram.Shapes;
//
// Now prepare and execute the layouter
layouter.Prepare();
layouter.Execute(10);
// Fit the result into the diagram bounds
layouter.Fit(50, 50, display1.Diagram.Width - 100, display1.Diagram.Height - 100);