/as3/net/inctm/components/Slider.as

/**
 * Slider.as
 * Keith Peters
 * version 0.97
 * 
 * A Horizontal Slider component for choosing values.
 * 
 * Copyright (c) 2009 Keith Peters
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package net.inctm.components
{
		import flash.display.DisplayObjectContainer;
        import flash.display.Sprite;
        import flash.events.Event;
        import flash.events.MouseEvent;
        import flash.geom.Rectangle;
        
        public class Slider extends Component
        {
                protected var _handle:Sprite;
                protected var _back:Sprite;
                protected var _backClick:Boolean = true;
                protected var _value:Number = 0;
                protected var _max:Number = 100;
                protected var _min:Number = 0;
                protected var _orientation:String;
                protected var _tick:Number = 1;
                
                public static const HORIZONTAL:String = "horizontal";
                public static const VERTICAL:String = "vertical";
                public var scrollerSize:int = 15;
                
                /**
                 * Constructor
                 * @param orientation Whether the slider will be horizontal or vertical.
                 * @param parent The parent DisplayObjectContainer on which to add this Slider.
                 * @param xpos The x position to place this component.
                 * @param ypos The y position to place this component.
                 * @param defaultHandler The event handling function to handle the default event for this component (change in this case).
                 */
                public function Slider(orientation:String = Slider.HORIZONTAL, parent:DisplayObjectContainer = null, xpos:Number = 0, ypos:Number =  0, defaultHandler:Function = null)
                {
                        _orientation = orientation;
                        super(parent, xpos, ypos);
                        if(defaultHandler != null)
                        {
                                addEventListener(Event.CHANGE, defaultHandler);
                        }
                }
                
                /**
                 * Initializes the component.
                 */
                override protected function init():void
                {
                        super.init();

                        if(_orientation == HORIZONTAL)
                        {
                                setSize(100, 10);
                        }
                        else
                        {
                                setSize(10, 100);
                        }
                }
                
                /**
                 * Creates and adds the child display objects of this component.
                 */
                override protected function addChildren():void
                {
                        _back = new Sprite();
                        //_back.filters = [getShadow(2, true)];
                        addChild(_back);
                        
                        _handle = new Sprite();
                        //_handle.filters = [getShadow(1)];
                        _handle.addEventListener(MouseEvent.MOUSE_DOWN, onDrag);
                        _handle.buttonMode = true;
                        _handle.useHandCursor = true;
                        addChild(_handle);
                }
                
                /**
                 * Draws the back of the slider.
                 */
                protected function drawBack():void
                {
                        _back.graphics.clear();
                        _back.graphics.beginFill(Style.BACKGROUND);
                        _back.graphics.drawRect(0, 0, _width, _height);
                        _back.graphics.endFill();
                        
                        if(_backClick)
                        {
                                _back.addEventListener(MouseEvent.MOUSE_DOWN, onBackClick);
                        }
                        else
                        {
                                _back.removeEventListener(MouseEvent.MOUSE_DOWN, onBackClick);
                        }
                }
                
                /**
                 * Draws the handle of the slider.
                 */
                protected function drawHandle():void
                {       
                        _handle.graphics.clear();
                        _handle.graphics.beginFill(Style.BUTTON_FACE);
                        if(_orientation == HORIZONTAL)
                        {
                                _handle.graphics.drawRect(0, 0, scrollerSize, _height);
                        }
                        else
                        {
                                _handle.graphics.drawRect(0, 0, _width, scrollerSize);
                        }
                        _handle.graphics.endFill();
                        positionHandle();
                }
                
                /**
                 * Adjusts value to be within minimum and maximum.
                 */
                protected function correctValue():void
                {
                        if(_max > _min)
                        {
                                _value = Math.min(_value, _max);
                                _value = Math.max(_value, _min);
                        }
                        else
                        {
                                _value = Math.max(_value, _max);
                                _value = Math.min(_value, _min);
                        }
                }
                
                /**
                 * Adjusts position of handle when value, maximum or minimum have changed.
                 * TODO: Should also be called when slider is resized.
                 */
                protected function positionHandle():void
                {
                        var range:Number;
                        if(_orientation == HORIZONTAL)
                        {
                                range = _width - _handle.width;
                                _handle.x = (_value - _min) / (_max - _min) * range;
                        }
                        else
                        {
                                range = _height - _handle.height;
                                _handle.y = _height - _handle.height - (_value - _min) / (_max - _min) * range;
                        }
                }
                
                
                
                
                ///////////////////////////////////
                // public methods
                ///////////////////////////////////
                
                /**
                 * Draws the visual ui of the component.
                 */
                override public function draw():void
                {
                        super.draw();
                        drawBack();
                        drawHandle();
                }
                
                /**
                 * Convenience method to set the three main parameters in one shot.
                 * @param min The minimum value of the slider.
                 * @param max The maximum value of the slider.
                 * @param value The value of the slider.
                 */
                public function setSliderParams(min:Number, max:Number, value:Number):void
                {
                        this.minimum = min;
                        this.maximum = max;
                        this.value = value;
                }
                
                
                
                
                ///////////////////////////////////
                // event handlers
                ///////////////////////////////////
                
                /**
                 * Handler called when user clicks the background of the slider, causing the handle to move to that point. Only active if backClick is true.
                 * @param event The MouseEvent passed by the system.
                 */
                protected function onBackClick(event:MouseEvent):void
                {
                        if(_orientation == HORIZONTAL)
                        {
                                _handle.x = mouseX - _height / 2;
                                _handle.x = Math.max(_handle.x, 0);
                                _handle.x = Math.min(_handle.x, _width - _height);
                                _value = _handle.x / (width - _height) * (_max - _min) + _min;
                        }
                        else
                        {
                                _handle.y = mouseY - _width / 2;
                                _handle.y = Math.max(_handle.y, 0);
                                _handle.y = Math.min(_handle.y, _height - _width);
                                _value = (_height - _width - _handle.y) / (height - _width) * (_max - _min) + _min;
                        }
                        dispatchEvent(new Event(Event.CHANGE));
                        
                }
                
                /**
                 * Internal mouseDown handler. Starts dragging the handle.
                 * @param event The MouseEvent passed by the system.
                 */
                protected function onDrag(event:MouseEvent):void
                {
                        stage.addEventListener(MouseEvent.MOUSE_UP, onDrop);
                        stage.addEventListener(MouseEvent.MOUSE_MOVE, onSlide);
                        if(_orientation == HORIZONTAL)
                        {
                                _handle.startDrag(false, new Rectangle(0, 0, _back.width - _handle.width, 0));
                        }
                        else
                        {
                                _handle.startDrag(false, new Rectangle(0, 0, 0, _back.height - _handle.height));
                        }
                }
                
                /**
                 * Internal mouseUp handler. Stops dragging the handle.
                 * @param event The MouseEvent passed by the system.
                 */
                protected function onDrop(event:MouseEvent):void
                {
                        stage.removeEventListener(MouseEvent.MOUSE_UP, onDrop);
                        stage.removeEventListener(MouseEvent.MOUSE_MOVE, onSlide);
                        stopDrag();
                }
                
                /**
                 * Internal mouseMove handler for when the handle is being moved.
                 * @param event The MouseEvent passed by the system.
                 */
                protected function onSlide(event:MouseEvent):void
                {
                        var oldValue:Number = _value;
                        if(_orientation == HORIZONTAL)
                        {
                                _value = _handle.x / (width - _height) * (_max - _min) + _min;
                        }
                        else
                        {
                                _value = (_height - _width - _handle.y) / (height - _width) * (_max - _min) + _min;
                        }
                        if(_value != oldValue)
                        {
                                dispatchEvent(new Event(Event.CHANGE));
                        }
                }
                
                
                
                
                ///////////////////////////////////
                // getter/setters
                ///////////////////////////////////
                
                /**
                 * Sets / gets whether or not a click on the background of the slider will move the handler to that position.
                 */
                public function set backClick(b:Boolean):void
                {
                        _backClick = b;
                        invalidate();
                }
                public function get backClick():Boolean
                {
                        return _backClick;
                }
                
                /**
                 * Sets / gets the current value of this slider.
                 */
                public function set value(v:Number):void
                {
                        _value = v;
                        correctValue();
                        positionHandle();
                        
                }
                public function get value():Number
                {
                        return Math.round(_value / _tick) * _tick;
                }
                
                /**
                 * Gets / sets the maximum value of this slider.
                 */
                public function set maximum(m:Number):void
                {
                        _max = m;
                        correctValue();
                        positionHandle();
                }
                public function get maximum():Number
                {
                        return _max;
                }
                
                /**
                 * Gets / sets the minimum value of this slider.
                 */
                public function set minimum(m:Number):void
                {
                        _min = m;
                        correctValue();
                        positionHandle();
                }
                public function get minimum():Number
                {
                        return _min;
                }
                
                /**
                 * Gets / sets the tick value of this slider. This round the value to the nearest multiple of this number. 
                 */
                public function set tick(t:Number):void
                {
                        _tick = t;
                }
                public function get tick():Number
                {
                        return _tick;
                }
                
        }
}