hintedlayout.lzx

<!--
* X_LZ_COPYRIGHT_BEGIN ****************************************************
* Copyright 2001-2008 Laszlo Systems, Inc.  All Rights Reserved.          *
* Use is subject to license terms.                                        *
* X_LZ_COPYRIGHT_END ******************************************************-->
<library> 
    <class name="hintedlayout" extends="layout">
        <!--- The primary axis for wrapping. -->
        <attribute name="axis" value="x" setter="this.setAxis( axis )" type="string"/>
        <!--- A pixel amount to use between the views controlled by the layout in
            both axes. By default, both xspacing and yspacing are set to this
            value. -->
        <attribute name="spacing" value="1"/>
        <!--- A pixel amount to offset the first view controlled by the layout in x
            axis -->
        <attribute name="xinset" value="0"/>
        <!--- A pixel amount to offset the first view controlled by the layout in y
            axis -->
        <attribute name="yinset" value="0"/>
        <!--- A pixel amount to use between the views controlled by the layout in
            the x axis. -->
        <attribute name="xspacing" value="${this.spacing}"/>
        <!--- A pixel amount to use between the views controlled by the layout in
            the y axis. -->
        <attribute name="yspacing" value="${this.spacing}"/>
        <!--- If given, a number of miliseconds to use to animate the views in to
            place.-->
        <attribute name="duration" value="0"/>
        <!--- The first view.  Set by the layout.-->
        <attribute name="first" value="null"/>
        <!--- The last view.  Set by the layout.-->
        <attribute name="last" value="null"/>


        <!--- @keywords private -->
        <method name="construct" args="parent, args">
            super.construct(parent, args);
            this.doupdateDelegate = new lz.Delegate(this, "doupdate");
        </method>

        <!--- @keywords private -->
        <method name="setAxis" args="a">
            <!-- CURRENTLY THIS METHOD IS NOT USED -->
            this.axis = a;
            this.otherAxis =  a == "x" ? "y" : "x"
            this.sizeAxis = a == "x" ? "width" : "height"
            this.otherSizeAxis = a == "x" ? "height" : "width"
        </method>

        <!--- @keywords private -->
        <method name="addSubview" args="newsub">
            this.doupdateDelegate.register( newsub,  'onwidth');
            this.doupdateDelegate.register( newsub,  'onheight');
            this.doupdateDelegate.register( newsub,  'onvisible');
            this.doupdateDelegate.register( this.immediateparent,  'onwidth');
            super.addSubview( newsub );
            this.doupdate(null);
        </method>

        <!--- This method is usually called automatically when any of the views
            controlled by the layout change their size , or when the size of
            layout's immediateparent changes. However it can be called directly
            to force the layout to update -->
        <method name="doupdate" args="v">
            
            if ( this.locked ) return;
            var l = this.subviews.length;

            // Only consider views that are visible
            var inuse = 0;
            for (var i = 0; i < l; i++ ) {
                var s = this.subviews[i];
                if (s.visible) inuse++;
            }

            var limit = this.immediateparent[this.sizeAxis];

            // position along this.axis
            var pos = this[this.axis + 'inset'];
            // position along this.otherAxis
            var otherpos = this[this.otherAxis + 'inset'];
            var maxdimension = 0;
            var space = this[this.axis + 'spacing'];    // spacing in axis dimension
            var otherspace = this[this.otherAxis + 'spacing'];    // spacing in other axis dimension

            // i is the view counter, j = visible view counter
            var j = 0;
            var firstv = null;
            for (var i = 0; i < l; i++ ) {
                var s = this.subviews[i];
                // set for directional nav
                s.lastview = false;
                s.firstview = false;
                if ( !s.visible ) continue;
                if (! firstv) firstv = s;
                s.animate(this.axis, pos, this.duration,false);
                s.animate(this.otherAxis, otherpos, this.duration,false);
                pos += s[this.sizeAxis];
                if ( j < (inuse - 1)) {
                    pos += space;
                    maxdimension = Math.max(maxdimension,s[this.otherSizeAxis]);
                    var next = i + 1;
                    while (this.subviews[next] && !this.subviews[next].visible) next++;
                    // reset prev value for directional nav
                    this.subviews[next].prev = null;

                    if ((pos + this.subviews[next][this.sizeAxis] > limit)) { 
                        // set prev and next values for directional navi
                        this.subviews[next].prev = s;
                        s.next = this.subviews[next];
                        pos = this[this.axis + 'inset'];
                        otherpos += maxdimension + otherspace;
                        maxdimension = 0;   // Reset the height/width after every row/column                    
                    } else {
                        // reset next value for directional nav
                        s.next = null
                    }
                }
                j++;
            }
            // set for directional nav
            if (firstv) {
                firstv.firstview = true;
                this.setAttribute('first', firstv);
            }
            if (s) {
                // Sets the last view appropriately when in 2x2 view.
                if (typeof this.parent.id != 'undefined' && this.parent.id ==
                    'gContent' && gContent.pagesize == 4){
                    if(typeof this.subviews[3] != 'undefined'){
                        this.subviews[3].lastview = true;
                        this.setAttribute('last', this.subviews[3]);
                    }
                } else {
                    if (s) s.lastview = true;
                    this.setAttribute('last', s);
                }
            }
            super.update();
            
        </method>
        <!--- @keywords private -->
        <method name="toString">
            return 'wrappinglayout for ' + this.immediateparent;
        </method>
    </class>
</library>