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copied!<blockquote> <p>I've tried making an object and tried using .getWidth and .getHeight but can't get it to work.</p> </blockquote> <p>That´s because you are not setting the width and height fields in JFrame, but you are setting them on local variables. Fields HEIGHT and WIDTH are inhereted from ImageObserver</p> <pre><code>Fields inherited from interface java.awt.image.ImageObserver ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH </code></pre> <p>See <a href="http://java.sun.com/javase/6/docs/api/javax/swing/JFrame.html" rel="nofollow noreferrer">http://java.sun.com/javase/6/docs/api/javax/swing/JFrame.html</a></p> <p>If width and height represent state of the frame, then you could refactorize them to fields, and write getters for them.</p> <p>Then, you could create a Constructor that receives both values as parameters</p> <pre><code>public class DrawFrame extends JFrame { private int width; private int height; DrawFrame(int _width, int _height){ this.width = _width; this.height = _height; //other stuff here } public int getWidth(){} public int getHeight(){} //other methods } </code></pre> <p>If widht and height are going to be constant (after created) then you should use the <strong>final</strong> modifier. This way, once they are assigned a value, they can´t be modified.</p> <blockquote> <p>Also, the variables i use in DrawCircle, should I have them in the constructor or not?</p> </blockquote> <p>The way it is writen now, will only allow you to create <strong>one type of circle</strong>. If you wan´t to create different circles, you should overload the constructor with one with arguments).</p> <p>For example, if you want to change the attributes xPoint and yPoint, you could have a constructor</p> <pre><code>public DrawCircle(int _xpoint, int _ypoint){ //build circle here. } </code></pre> <p>EDIT: </p> <pre><code>Where does _width and _height come from? </code></pre> <p>Those are arguments to constructors. You set values on them when you call the Constructor method.</p> <blockquote> <p>In DrawFrame I set width and height. In DrawCircle I need to access the width and height of DrawFrame. How do I do this?</p> </blockquote> <pre><code>DrawFrame(){ int width = 400; int height =400; /* * call DrawCircle constructor */ content.pane(new DrawCircle(width,height)); // other stuff } </code></pre> <p>Now when the DrawCircle constructor executes, it will receive the values you used in DrawFrame as _width and _height respectively.</p> <p>EDIT:</p> <p>Try doing</p> <pre><code> DrawFrame frame = new DrawFrame();//constructor contains code on previous edit. frame.setPreferredSize(new Dimension(400,400)); </code></pre> <p><a href="http://java.sun.com/docs/books/tutorial/uiswing/components/frame.html" rel="nofollow noreferrer">http://java.sun.com/docs/books/tutorial/uiswing/components/frame.html</a></p>

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