I recently had the privilege of attending a customer-training session given by one of our Flex architects. The session covered component creation in Flex. I volunteered a component I wrote a while back as a test case to have our expert help us write better components.
This gauge component is one outcome of that session (another is an article I wrote which will appear on the Macromedia site early next year). Feel free to download the component. It includes some skin files, too. I placed comments throughout to help guide you when building your own components.
Comments
Could i translate your Archives to chinese .Release to my website~?
Could i translate your Archives to chinese .Release to my website~?
I have two questions.
First Question,
I modified your Gauge class that I add TRACE() function in all function and saw log.
Follow is log message. I am wandering about measure() method that was not called.
=============================================
classConstruct() start
classConstruct() end
Gauge() start
Gauge() end
init() start
init() end
createChildren() start
createChildren() end
test.mxml::initialize
ê²½ê³ : invalidateSizeì?´(ê°€) 함수가 아닙니다.
at MovieClip::_measureSizes()
ê²½ê³ : invalidateLayoutì?´(ê°€) 함수가 아닙니다.
at MovieClip::_measureSizes()
ê²½ê³ : invalidateì?´(ê°€) 함수가 아닙니다.
at Object::_finishConstruction()
commitProperties() start
commitProperties() end
ê²½ê³ : invalidateì?´(ê°€) 함수가 아닙니다.
at Object::_finishConstruction()
ê²½ê³ : invalidateSizeì?´(ê°€) 함수가 아닙니다.
at mx_managers_LayoutManager::measureSizes()
ê²½ê³ : invalidateLayoutì?´(ê°€) 함수가 아닙니다.
at mx_managers_LayoutManager::measureSizes()
size() start
size() end
layoutChildren() start
layoutChildren() end
draw() start
rotateNeedle() start
rotateNeedle() end
draw() end
test.mxml::creationComplete
layoutChildren() start
layoutChildren() end
=============================================
As you can see, there is not measure() function.
I want to know why?
Second Question,
Follow is a part of test.mxml. This function change value of the mygauge.
=================================================================
function updateGauge(event) {
mygauge.value=event.target.value;
bigauge.value=event.target.value;
}
=================================================================
Follow is a part of Gauge class. This set function call the dispatchEvent() function.
=================================================================
[Inspectable(category="Common",type="Number",defaultValue=0)]
[ChangeEvent("changeValue")]
public function set value(n:Number) : Void {
trace(“set value() start”);
__value = n;
__needleChanged = true;
invalidate(); // this will trigger draw() method
dispatchEvent({type:”changeValue”});
trace(“set value() end”);
}
=================================================================
I want to know where is handler of event.
When this set value() function is called, what is happen?
Please, answer me about that.
Thank you for your reading.
The measure method is called only if the Flex layout system needs to call it. For example, if you specify the width and height on a component, the measure method will not get called.
Thank you for your answer.
I have another question.
I cann’t find function ‘createObject2()’ in Gauge class but there is not error.
I know that creationObject2 method call init() and createChildren(), right?
I am wandring about it. Please, tell me why?
Thanks.
I am so sorry.
not createObject2() but constructObject2().
How can I delete my comment?