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copied!<p>Please reconsider what you are doing there:</p> <ol> <li>In line 4 of your loop, you <code>alloc</code> an instance of <code>GetColor</code> — which you never use again. Ask yourself: Does that make any sense from a design point of view?</li> <li>In that same line, if you don't violate Cocoa's naming-conventions, you create a UIColor that is never released...</li> <li>Then in line 8 you <em>release the class-object</em> of <code>DrawLine</code> (ditto that for the next line and the <code>GetColor</code>-class). <strong>This is terribly, horribly wrong!</strong></li> </ol> <p>Please visit the <a href="http://developer.apple.com/library/ios/#documentation/Cocoa/Conceptual/MemoryMgmt/MemoryMgmt.html" rel="nofollow">Memory Management Programming Guide</a> at the iOS Dev-Center and read the first two sections (again)!</p> <p>Besides that, re-evaluate your design:</p> <ul> <li>Should <code>GetColor</code> really be a class, so that you create instances? Wouldn't a simple helper-function for color interpolation make more sense in this context?</li> <li>If it should be a class, why not create just one instance of it <em>outside of the loop</em> and simply query it repeatedly for the colors?</li> <li>Do you really need a subclass of UIView to draw a single straight, solid, single-colored line? If the lines need not be updated, you should (as Richard and nacho4d suggested) draw all of them in one object (e.g. by a custom UIView or by a delegate of CALayer implementing the <code>drawLayer:inContext:</code> method). If you need to update those lines later, you could simply (ab)use CALayer...</li> </ul> <p>In the latter case, your problem then becomes:</p> <ol> <li>Calculate your random coordinates.</li> <li>Calculate your color.</li> <li>Create an <em>opaque</em> CALayer with<br> a) that color as its backgroundColor,<br> b) a width of 20 * sqrt(2),<br> c) a height of whatever-you-want-to-be-the-width-of-that-line,<br> d) your point as its origin and<br> e) a <code>rotation</code> of 45. </li> <li>Add that layer as a sublayer to <code>self.view</code>'s layer.</li> </ol> <p>Cheers<br> Daniel</p>

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