java - Enabling/Disabling drawing of a JFreeChart -

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i have chart created shown below, , adding values timeseries (in different location in program). chartpanel contained within jtabbedpane, , not redraw chart unless it's tab being displayed. there way me signal rendering should not occur when new data comes timeseries unless tab 1 being shown? i'm guessing there call signals data has been updated , new rendering needed, want intercept call , nothing if tab not being shown, let call through if tab being shown, , call once manually when user switches tab. isn't major issue 1 chartpanel in background, have few on different tabs , it's starting eat cpu nasty update 4-5 charts constantly. 

    saccuracy = new timeseries("a");     timeseriescollection dataset = new timeseriescollection(saccuracy);     jfreechart c = chartfactory.createtimeserieschart("accuracy",             "", "percent", dataset, false, false, false);      chartpanel cp = new chartpanel(c);

i've faced same problem whereby jfreechart api clunky , repaints entire chart whenever single datapoint added resulting in large rendering overhead.

the way i've solved implement own underlying model (e.g. xydataset implementation) aware of when chart containing being displayed, , only propagate events when chart visible - if chart not visible model should defer firing of events until later; e.g.

public class myxydataset extends abstractxydataset {   private boolean shown;   private boolean pendingevent;    /**    * called when chart containing dataset being displayed    * (e.g. hook selection listener listens tab selection events).    */   public void setshown(boolean shown) {     this.shown = shown;      if (this.shown && this.pendingevent) {       this.pendingevent = false;       firedatasetchanged();     }   }    public void adddatapoint(double x, double y) {     // todo: add underlying collection.      if (this.shown) {       // chart displayed propagate event immediately.       firedatasetchanged();     } else {       // chart hidden delay firing of event record need fire one.       this.pendingevent = true;     }   } }

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