source: [view]
define("dojo/dnd/autoscroll", ["dojo", "dojo/window"], function(dojo) {
dojo.getObject("dnd", true, dojo);
dojo.dnd.getViewport = dojo.window.getBox;
dojo.dnd.V_TRIGGER_AUTOSCROLL = 32;
dojo.dnd.H_TRIGGER_AUTOSCROLL = 32;
dojo.dnd.V_AUTOSCROLL_VALUE = 16;
dojo.dnd.H_AUTOSCROLL_VALUE = 16;
dojo.dnd.autoScroll = function(e){
// summary:
// a handler for onmousemove event, which scrolls the window, if
// necesary
// e: Event
// onmousemove event
// FIXME: needs more docs!
var v = dojo.window.getBox(), dx = 0, dy = 0;
if(e.clientX < dojo.dnd.H_TRIGGER_AUTOSCROLL){
dx = -dojo.dnd.H_AUTOSCROLL_VALUE;
}else if(e.clientX > v.w - dojo.dnd.H_TRIGGER_AUTOSCROLL){
dx = dojo.dnd.H_AUTOSCROLL_VALUE;
}
if(e.clientY < dojo.dnd.V_TRIGGER_AUTOSCROLL){
dy = -dojo.dnd.V_AUTOSCROLL_VALUE;
}else if(e.clientY > v.h - dojo.dnd.V_TRIGGER_AUTOSCROLL){
dy = dojo.dnd.V_AUTOSCROLL_VALUE;
}
window.scrollBy(dx, dy);
};
dojo.dnd._validNodes = {"div": 1, "p": 1, "td": 1};
dojo.dnd._validOverflow = {"auto": 1, "scroll": 1};
dojo.dnd.autoScrollNodes = function(e){
// summary:
// a handler for onmousemove event, which scrolls the first avaialble
// Dom element, it falls back to dojo.dnd.autoScroll()
// e: Event
// onmousemove event
// FIXME: needs more docs!
for(var n = e.target; n;){
if(n.nodeType == 1 && (n.tagName.toLowerCase() in dojo.dnd._validNodes)){
var s = dojo.getComputedStyle(n);
if(s.overflow.toLowerCase() in dojo.dnd._validOverflow){
var b = dojo._getContentBox(n, s), t = dojo.position(n, true);
//console.log(b.l, b.t, t.x, t.y, n.scrollLeft, n.scrollTop);
var w = Math.min(dojo.dnd.H_TRIGGER_AUTOSCROLL, b.w / 2),
h = Math.min(dojo.dnd.V_TRIGGER_AUTOSCROLL, b.h / 2),
rx = e.pageX - t.x, ry = e.pageY - t.y, dx = 0, dy = 0;
if(dojo.isWebKit || dojo.isOpera){
// FIXME: this code should not be here, it should be taken into account
// either by the event fixing code, or the dojo.position()
// FIXME: this code doesn't work on Opera 9.5 Beta
rx += dojo.body().scrollLeft;
ry += dojo.body().scrollTop;
}
if(rx > 0 && rx < b.w){
if(rx < w){
dx = -w;
}else if(rx > b.w - w){
dx = w;
}
}
//console.log("ry =", ry, "b.h =", b.h, "h =", h);
if(ry > 0 && ry < b.h){
if(ry < h){
dy = -h;
}else if(ry > b.h - h){
dy = h;
}
}
var oldLeft = n.scrollLeft, oldTop = n.scrollTop;
n.scrollLeft = n.scrollLeft + dx;
n.scrollTop = n.scrollTop + dy;
if(oldLeft != n.scrollLeft || oldTop != n.scrollTop){ return; }
}
}
try{
n = n.parentNode;
}catch(x){
n = null;
}
}
dojo.dnd.autoScroll(e);