ninja captain

<?xml version="1.0"?>
<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" xmlns:local="com.*" 
	initialize="init()" width="600" height="520">
	<mx:Panel title="Line Chart">
		<mx:LineChart id="chart1" mouseDown="startDraw(event)" mouseUp="finishDraw(event)" 
			mouseMove="showDraw(event)" width="510">
 
			<!-- zoom window is drawn here -->
			<mx:annotationElements>
				<mx:CartesianDataCanvas id="chartCanvas"/>
			</mx:annotationElements>
 
			<mx:horizontalAxis>
				<mx:LinearAxis id="haxis"/>
			</mx:horizontalAxis>
 
			<mx:verticalAxis>
				<mx:LinearAxis id="vaxis"/>
			</mx:verticalAxis>
 
			<mx:series>
				<mx:LineSeries filterData="false" id="series1" xField="month" yField="profit" 
					displayName="Profit" dataProvider="{profits}"/>
			</mx:series>
 
		</mx:LineChart>
	</mx:Panel>
 
	<mx:Button label="Reset Zoom" click="resetZoom()" />
</mx:Application>

[Bindable]
private var profits:Array;
private var dragStart:Point;
private var dragEnd:Point;
private var zooming:Boolean;
 
// initializes the data provider with random data
private function init():void{
	profits = new Array({month: 0, profit: 15});
	for(var i:int=1; i<40; i++)
		profits.push({month: i, profit: Math.round(Math.random()*25-10)+profits[i-1].profit});
}
 
// sets the start point of the zoom window
private function startDraw(e:MouseEvent):void{
	zooming = true;
	dragStart = new Point(series1.mouseX, series1.mouseY);
}
 
// draws the zoom window as your mouse moves
private function showDraw(e:MouseEvent):void{
	if(zooming){
		dragEnd = new Point(series1.mouseX, series1.mouseY);
 
		// finds the top-left and bottom-right ponits of the zoom window
		var TL:Point = new Point();  // top-left point
		var BR:Point = new Point();  // bottom-right point
		if(dragStart.x < dragEnd.x){
			TL.x = dragStart.x;
			BR.x = dragEnd.x;
		}
		else{
			TL.x = dragEnd.x;
			BR.x = dragStart.x;
		}
		if(dragStart.y < dragEnd.y){
			TL.y = dragStart.y;
			BR.y = dragEnd.y;
		}
		else{
			TL.y = dragEnd.y;
			BR.y = dragStart.y;
		}
 
		// prevents the zoom window from going off the canvas
		if(TL.x < 0) TL.x = 0;
		if(BR.x > chartCanvas.width-1) BR.x = chartCanvas.width-1;
		if(TL.y < 0) TL.y = 0;
		if(BR.y > chartCanvas.height-1) BR.y = chartCanvas.height-1;
 
		// draw the actual zoom window
		chartCanvas.graphics.clear();
		chartCanvas.graphics.lineStyle(1, 0x000000, 0.25);
		chartCanvas.graphics.beginFill(0xd4e3f0,0.5);
		chartCanvas.graphics.drawRect(TL.x, TL.y, BR.x-TL.x, BR.y-TL.y);
		chartCanvas.graphics.endFill();
	}
}
 
// clears the drawing canvas and sets the new max/mins
private function finishDraw(e:MouseEvent):void{
	zooming = false;
	chartCanvas.clear();
 
	// converts the drag coordinates into axis data points
	var chartValStart:Array = chartCanvas.localToData(dragStart);
	var chartValEnd:Array = chartCanvas.localToData(dragEnd);
 
	// sets the new maximum and minimum for both axes
	haxis.minimum = (chartValStart[0] < chartValEnd[0]) ? chartValStart[0] : chartValEnd[0];
	haxis.maximum = (chartValStart[0] < chartValEnd[0]) ? chartValEnd[0] : chartValStart[0];
	vaxis.minimum = (chartValStart[1] < chartValEnd[1]) ? chartValStart[1] : chartValEnd[1];
	vaxis.maximum = (chartValStart[1] < chartValEnd[1]) ? chartValEnd[1] : chartValStart[1];
}
 
// resets the axis max/mins
private function resetZoom():void{
	haxis.minimum = NaN; 
	haxis.maximum = NaN; 
	vaxis.minimum = NaN; 
	vaxis.maximum = NaN;
}

<mx:horizontalAxis>
	<mx:DateTimeAxis id="haxis"/>
</mx:horizontalAxis>

var ds:Date = new Date(chartValStart[0]);
var de:Date = new Date(chartValEnd[0]);
haxis.minimum = (ds < de ? ds:de);
haxis.maximum = (ds < de ? de:ds);
vaxis.minimum = (chartValStart[1] < chartValEnd[1]) ? chartValStart[1] : chartValEnd[1];
vaxis.maximum = (chartValStart[1] < chartValEnd[1]) ? chartValEnd[1] : chartValStart[1];

private function resetZoom():void{
	haxis.minimum = null; 
	haxis.maximum = null; 
	vaxis.minimum = NaN; 
	vaxis.maximum = NaN;
}