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Add the following constants:

Code Block

language	java

/** default value for spacing between nodes. */
private static final float DEFAULT_SPACING = 15.0f;

Use the following code as the skeleton of the doLayout(...) method:

Code Block

language	java

progressMonitor.begin("Login_name layouter", 1);
KShapeLayout parentLayout = parentNode.getData(KShapeLayout.class);

float objectSpacing = parentLayout.getProperty(LayoutOptions.SPACING);
if (objectSpacing < 0) {
    objectSpacing = DEFAULT_SPACING;
}

float borderSpacing = parentLayout.getProperty(LayoutOptions.BORDER_SPACING);
if (borderSpacing < 0) {
    borderSpacing = DEFAULT_SPACING;
}

// TODO: Insert actual layout code.

progressMonitor.done();

It is now time to write the code that places the nodes. Here's two suggestions for how you can place them:
The simplest way is to place nodes in a row, next to each other. To make this more interesting, you could also place the nodes along the graph of a Sine function.

Another way might be to place them in a square or a circle. You would have to think about how exactly to align the nodes, which may well vary in size

Your code should place them next to each other in a row, as seen in the screenshot at the beginning of the tutorial

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Info

title	Tips

The following tips might come in handy...

Read the documentation of the KGraph and KLayoutData meta models. The input to the layout algorithm is a KNode that has child KNodes for every node in the graph. Iterate over these nodes by iterating over the getChildren() list of the parentNode argument.

Retrieve the size of a node and set its position later using the following code:

Code Block

language	java

KShapeLayout nodeLayout = node.getData(KShapeLayout.class);

// Retrieving the size
float width = nodeLayout.getWidth();
float height = nodeLayout.getHeight();

// Setting the position
nodeLayout.setXpos(x);
nodeLayout.setYpos(y);

objectSpacing is the spacing to be left between each pair of nodes.
borderSpacing is the spacing to be left to the borders of the drawing. The top left node's coordinates must therefore be at least (borderSpacing, borderSpacing).
At the end of the method, set the width and height of parentLayout such that it is large enough to hold the whole drawing, including borders.
A complete layout algorithm will of course also route the edges between the nodes. Ignore that for now – you will do this at a later step.

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