streamscrubber.lzx

<library>
        
<!---
   enclosing view must have the following attributes:
   stream  the stream to control, assume it is paused
   min     min 'x' value
   max     max 'x' value

   @keywords private -->
<class name="_scrubstate" extends="state">
    
    <!--- @keywords private -->
    <attribute name="__scrubstate_xdoffset" value="$once{this.xoffset - this.getMouse( 'x' )}"/>

    <attribute name="x" value="this.__scrubstate_getnewpos(                 this.immediateparent.getMouse( 'x' ) + this.__scrubstate_xdoffset)" when="always"/>

    <!--- @keywords private -->
    <method name="__scrubstate_getnewpos" args="newpos"> 
        if (newpos < min) newpos = min;
        if (newpos > max) newpos = max;
        if (this.x != newpos) { // new scrubber value
            //Debug.write('new newpos=%w',newpos);
            var totalLength = this.max - this.min;
            var pos = newpos - this.min;
            var newtime = pos/totalLength * this.stream.totaltime;

            /**
            Debug.write('pos=%w totalLength=%w perc=%w',
                        pos, totalLength, pos/totalLength);
            Debug.write('totaltime=%w newtime=%w',
                this.stream.totaltime, newtime);
            **/
            this.stream.seek(newtime);
        }
        return newpos;
    
    </method> 
</class>


<class name="streamscrubber">
    <!--- the stream to control -->
    <attribute name="stream" value="null"/>
    <!--- true when user has the mouse down and is scrubbing the stream -->
    <attribute name="scrubbing" value="false" type="boolean"/>
    <!--- min 'x' value, defaults to zero (typically the left side of parent) -->
    <attribute name="min" value="0" type="number"/>
    <!--- max 'x' value, defaults to the right side of the parent -->
    <attribute name="max" value="$once{parent.width-this.width}" type="number"/>

    <!--- read only -->
    <attribute name="time" value="0"/>
    <!--- read only -->
    <attribute name="totaltime" value="0"/>
    <!--- read only -->
    <attribute name="progress" value="0"/>

    <!--- @keywords private -->
    <attribute name="_waspaused" value="true" type="boolean"/>

    <!--- @keywords private -->
    <attribute name="_trackdel" value="null"/>

    <!--- @keywords private -->
    <event name="onstream"/>
    <!--- @keywords private -->
    <event name="ontime"/>
    <!--- @keywords private -->
    <event name="ontotaltime"/>
    <!--- @keywords private -->
    <event name="onprogress"/>
    
    <!--- @keywords private -->
    <setter name="stream" args="newStream">
        this.stream = newStream;
        if (!_trackdel) {
            this._trackdel = new LzDelegate(this, "_trackprogress");
        }
        this._trackdel.unregisterAll();
        this._trackdel.register(this.stream, 'ontime');
        this._trackdel.register(this.stream, 'ontotaltime');
        this._trackdel.register(this, 'onmin');

        if (this.onstream) this.onstream.sendEvent(this);
    </setter>

    <!--- @keywords private -->
    <handler name="onmousedown">
        if (!this.stream) {
            Debug.warn('streamscrubber %w: null stream');
        }
        this._waspaused = this.stream.paused;
        this.stream.pause(true);
        this.setAttribute('scrubbing', true);
        this._trackdel.unregisterAll();
        this.scrubaction.apply(); 
    </handler>
    
    <!--- @keywords private -->
    <handler name="onmouseup">
        this.scrubaction.remove(); 
        this.setAttribute('scrubbing', false);
        this._trackdel.register(this.stream, 'ontime');
        this._trackdel.register(this.stream, 'ontotaltime');
        if (!this._waspaused) this.stream.pause(false);
    </handler>

    <!--- when the user is not scrubbing track the progress of the
          stream by moving x when time passes
          @keywords private -->
    <method name="_trackprogress" args="ignore=null"> 
        var newTime = false, newTotal = false;
        if (this.time != this.stream.time) {
            newTime = true;
            this.time = this.stream.time;
        }
        if (this.totaltime != this.stream.totaltime) {
            newTotal = true;
            this.totaltime = this.stream.totaltime;
        }
        this.progress = this.totaltime > 0 ?
            this.time / this.totaltime : 0;
        
        if (this.inited) {
            var newx = this.min + (this.max-this.min) * this.progress;
            this.setAttribute('x', newx );
        }
        if (this.ontime && newTime) this.ontime.sendEvent(this);
        if (this.ontotaltime && newTotal) this.ontotaltime.sendEvent(this);
        if (this.onprogress) this.onprogress.sendEvent(this);    
        
    </method>

    <_scrubstate name="scrubaction"/>
</class>        
</library>
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* Copyright 2001-2009 Laszlo Systems, Inc.  All Rights Reserved.              *
* Use is subject to license terms.                                            *
* X_LZ_COPYRIGHT_END ****************************************************** -->