Adding scrollbars to canvas!!

hi everybody,
a have a simple ??
i'm working on a chat application. my message displaying area is a canvas.i have added scroll-bars to it using scroll-pane
"sp = new ScrollPane(ScrollPane.SCROLLBARS_ALWAYS);"
now what i want is the scrollbars should adjust automatically to
display the last message and also i should be able to adjust them
manually so that i can view the previous messages.
i have tried setScrollposition() it works well also but then i'm not
able to adjust scrollbars manually.
this interface is in AWT.
please tell me a solution.its a bit urgent.
thankx and regards
asheet

Because your canvas is growing.(I think)
The new size of the canvas causes it to be layd out again. And laying out a component usually causes flickering (depending on the plattform). I guess the workaround would be to use a canvas just as big as the shown part of it. Add a scrollbar by its side (not a scrollpane) and use the scrollposition to choose what part of the text that should be painted. That way you can use doublebuffering, and avoid the problem completly. (No resizing of components means nothing is layd out again)
Ragnvald Barth
Software engineer

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Hello,
I am trying to connect dynamic text to scrollbar and buttons. I did tutorial and Lynda.com and practically pasted the code in with my file names and for some reason it does not work. It says I have a "Access of Undefined Property mask_mc" Did I need to create a variable for this? I didn't in the tutorial.
Right now I have the dynamic text loading successfuly in 2 different places and I wantd to add the scrollbar. I put the variables on frame 1 code and then I put the actually load code on the frame where it is needed.
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Thanks! Sandra
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var targetScroll:Number = philText_mc.y;
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Hello again,
Maybe I am asking this question wrong. Instead of making you try and figure out what's going on in my file what I really need to know is how you would take this code I am attaching and make it happen on another frame besides frame 1 and it doesn't appear on frame 1. I think this may help me understand a little better.
Also another way I was thinking to get around this would be to pull in an external swf into the spot where I want this text to go because I can make the scrollbars and external text work when it is the only thing going on in the movie. Would this be a bad way to set this up? and also SInce it is an external movie would I have maintimeline issues with mouse/scroller control?
thanks! sandra
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var textLoader:URLLoader = new URLLoader();
var textFile:URLRequest = new URLRequest("text/external.txt");
var scrollPercent:Number = 0;
var minScroll:Number;
var maxScroll:Number;
var targetScroll:Number = text_mc.y;
var easing:Number = 5;
var scrollAmt:Number = 15;
var scrollDirection:Number = 0;
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function dragScroller(event:MouseEvent):void
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function setScrollPercent(event:Event):void
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        scrollPercent = 0;
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        scrollPercent = 1;
    targetScroll = (scrollPercent * (maxScroll - minScroll)) + minScroll;
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function scrollDown(event:MouseEvent):void
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function setDirection(dir:Number):void
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    stage.addEventListener(MouseEvent.MOUSE_UP, stopScrolling);
    stage.removeEventListener(Event.ENTER_FRAME, setScrollPercent);
function scrollText(event:Event):void
    targetScroll += scrollDirection;
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        text_mc.y = maxScroll;
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scroller_mc.buttonMode = true;
text_mc.external_txt.autoSize = TextFieldAutoSize.LEFT;
scroller_mc.addEventListener(MouseEvent.MOUSE_DOWN, dragScroller);
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Adding scrollbars to canvas!!

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