How to automatically adjust the dimensions of diagram elements to fit their contents using the Rational Rhapsody API

Answer

This is possible using the IBM Rational Rhapsody API.

You must do the following:

1. Retrieve the font information from the diagram element
   
   
2. Render the text in a separate Canvas object using that font data and calculate its dimensions in pixels
   
   
3. Set the width and height of the diagram element using these dimensions so that the full text fits within the element.

For example:

import java.awt.Canvas;



import java.awt.Font;

import java.awt.FontMetrics;

import java.awt.font.TextAttribute;

import java.awt.font.TextMeasurer;

import java.awt.geom.Rectangle2D;

import java.text.AttributedCharacterIterator;

import java.text.AttributedString;

import java.util.List;



import com.telelogic.rhapsody.core.IRPApplication;

import com.telelogic.rhapsody.core.IRPDiagram;

import com.telelogic.rhapsody.core.IRPGraphElement;

import com.telelogic.rhapsody.core.IRPModelElement;

import com.telelogic.rhapsody.core.IRPState;

import com.telelogic.rhapsody.core.RhapsodyAppServer;





public class Test {



	public static void main(String[] args) {

		IRPApplication app = RhapsodyAppServer.getActiveRhapsodyApplication();

		IRPDiagram diagram = (IRPDiagram)app.getSelectedElement();

		if(diagram instanceof IRPDiagram) {

			

			List<IRPGraphElement> lGrElements = diagram.getGraphicalElements().toList();

			

			for (IRPGraphElement grElement : lGrElements) {

				

				

				IRPModelElement grElementMoEl = grElement.getModelObject();

		        IRPState state = null;



                try {

                        

                    state = (IRPState) grElementMoEl;



                    if (state != null) {

                        String actionBody = state.getEntryAction();

                        

                        

                        if (!actionBody.isEmpty()) {

                        	String fontName = grElement.getGraphicalProperty("TextFontName").getValue(); 

	                        String fontSizeString = grElement.getGraphicalProperty("TextFontSize").getValue(); 

	                        String[] splittedLines = actionBody.split("\\r?\\n"); 

	                        

	                        int maxWidthInt = 0, maxHeightInt = 0, fontSize = 0;

	                        double maxWidthDouble = 0, maxHeightDouble = 0;

	                        

	                        if (fontSizeString.isEmpty()) {

	                                fontSize = 10; // Default value

	                        } else {

	                                fontSize = Integer.parseInt(fontSizeString);

	                        }	                        



	                        int screenRes = java.awt.Toolkit.getDefaultToolkit().getScreenResolution(); 

	                        int fontSizeNew = (int) Math.round(fontSize * (screenRes / 60));                 

	                        Font f = new Font(fontName, Font.PLAIN, fontSizeNew); 

	                        Canvas c = new Canvas(); 

	                        FontMetrics fm = c.getFontMetrics(f); 

	                                                        

	                        for (int i = 0; i < splittedLines.length; i++) { 

	                                AttributedString as = new AttributedString(splittedLines[i]); 

	                                                                

	                                as.addAttribute(TextAttribute.FONT, f); 

	                                                                

	                                AttributedCharacterIterator aci = as.getIterator(); 

	                                TextMeasurer tm = new TextMeasurer(aci, fm.getFontRenderContext()); 

	                                Rectangle2D r2d = tm.getLayout(0, aci.getEndIndex()).getBounds(); 

	                                                                

	                                if (r2d.getWidth() > maxWidthDouble) { 

	                                        maxWidthDouble = r2d.getMaxX(); 

	                                } 

	                                                                

	                                maxHeightDouble += (r2d.getHeight() + r2d.getMaxY()) ; 

	                        } 

	                                                        

	                        maxHeightInt = (int) Math.round(maxHeightDouble); 

	                        maxWidthInt = (int) Math.round(maxWidthDouble); 

	                                                        

	                        grElement.setGraphicalProperty("Width", String.valueOf(maxWidthInt)); 

	                        grElement.setGraphicalProperty("Height", String.valueOf(maxHeightInt));

	                                                        

	                        

                                

                        }

                    }

                } catch (Exception e) {

                        System.out.println(e.getMessage());

                }

		

			}

		}

	}



}