Flash CS5: The Missing Manual

Removing Lines and Shapes

So far, this chapter has shown several ways to draw lines and shapes. This section tells how to make them disappear. The Graphics class has a clear() method. When you use this method, it erases the drawings that were created in the object, resets the line and fill style settings, and moves the virtual pen back to the 0,0 position. The clear() method is a multipurpose cleanup tool. Here's an example of the clear() method in action. A text field is added to the code that begins on Shape, Sprite, and Movie Clip for Drawings. This text field serves as kind of a button that, when clicked, triggers the clear() method to remove the drawings on the mcCanvas movie clip. For the complete code, check out 18-9_Clear_Graphic.fla in the Missing CD (www.missingmanuals.com/cds).

1 var tfPoem:TextField = new TextField(); 2 var mcCanvas:MovieClip = new MovieClip(); 3 4 tfPoem.text = "Twas brillig, and the slithy toves"; 5 tfPoem.x = 110; 6 tfPoem.y = 110; 7 tfPoem.autoSize = TextFieldAutoSize.LEFT; 8 mcCanvas.addChild(tfPoem); 9 10 mcCanvas.graphics.beginFill(0x99FFFF); 11 mcCanvas.graphics.drawRect(100,100,200,150); 12 13 addChild(mcCanvas); 14 15 var txtRemoveRectangle = new TextField(); 16 txtRemoveRectangle.text = "Click here to remove the rectangle"; 17 txtRemoveRectangle.x = 110; 18 txtRemoveRectangle.y = 250; 19 txtRemoveRectangle.autoSize = TextFieldAutoSize.LEFT; 20 addChild(txtRemoveRectangle); 21 22 txtRemoveRectangle.addEventListener(MouseEvent.CLICK,clickListener); ...