- Author:
- David Nickerson <nickerso@users.sourceforge.net>
- Date:
- 2009-07-16 02:00:03+12:00
- Desc:
- the starting point for the HH tutorial example
- Permanent Source URI:
- https://models.fieldml.org/workspace/a1/rawfile/f6a8f90307388eb4b040ee3566b84d88b59247f7/dojo-presentation/js/dojo/dijit/_base/focus.js
dojo.provide("dijit._base.focus");
// summary:
// These functions are used to query or set the focus and selection.
//
// Also, they trace when widgets become actived/deactivated,
// so that the widget can fire _onFocus/_onBlur events.
// "Active" here means something similar to "focused", but
// "focus" isn't quite the right word because we keep track of
// a whole stack of "active" widgets. Example: Combobutton --> Menu -->
// MenuItem. The onBlur event for Combobutton doesn't fire due to focusing
// on the Menu or a MenuItem, since they are considered part of the
// Combobutton widget. It only happens when focus is shifted
// somewhere completely different.
dojo.mixin(dijit,
{
// _curFocus: DomNode
// Currently focused item on screen
_curFocus: null,
// _prevFocus: DomNode
// Previously focused item on screen
_prevFocus: null,
isCollapsed: function(){
// summary: tests whether the current selection is empty
var _document = dojo.doc;
if(_document.selection){ // IE
var s=_document.selection;
if(s.type=='Text'){
return !s.createRange().htmlText.length; // Boolean
}else{ //Control range
return !s.createRange().length; // Boolean
}
}else{
var _window = dojo.global;
var selection = _window.getSelection();
if(dojo.isString(selection)){ // Safari
return !selection; // Boolean
}else{ // Mozilla/W3
return selection.isCollapsed || !selection.toString(); // Boolean
}
}
},
getBookmark: function(){
// summary: Retrieves a bookmark that can be used with moveToBookmark to return to the same range
var bookmark, selection = dojo.doc.selection;
if(selection){ // IE
var range = selection.createRange();
if(selection.type.toUpperCase()=='CONTROL'){
if(range.length){
bookmark=[];
var i=0,len=range.length;
while(i<len){
bookmark.push(range.item(i++));
}
}else{
bookmark=null;
}
}else{
bookmark = range.getBookmark();
}
}else{
if(window.getSelection){
selection = dojo.global.getSelection();
if(selection){
range = selection.getRangeAt(0);
bookmark = range.cloneRange();
}
}else{
console.warn("No idea how to store the current selection for this browser!");
}
}
return bookmark; // Array
},
moveToBookmark: function(/*Object*/bookmark){
// summary: Moves current selection to a bookmark
// bookmark: This should be a returned object from dojo.html.selection.getBookmark()
var _document = dojo.doc;
if(_document.selection){ // IE
var range;
if(dojo.isArray(bookmark)){
range = _document.body.createControlRange();
//range.addElement does not have call/apply method, so can not call it directly
//range is not available in "range.addElement(item)", so can't use that either
dojo.forEach(bookmark, function(n){
range.addElement(n);
});
}else{
range = _document.selection.createRange();
range.moveToBookmark(bookmark);
}
range.select();
}else{ //Moz/W3C
var selection = dojo.global.getSelection && dojo.global.getSelection();
if(selection && selection.removeAllRanges){
selection.removeAllRanges();
selection.addRange(bookmark);
}else{
console.warn("No idea how to restore selection for this browser!");
}
}
},
getFocus: function(/*Widget?*/menu, /*Window?*/openedForWindow){
// summary:
// Returns the current focus and selection.
// Called when a popup appears (either a top level menu or a dialog),
// or when a toolbar/menubar receives focus
//
// menu:
// The menu that's being opened
//
// openedForWindow:
// iframe in which menu was opened
//
// returns:
// A handle to restore focus/selection
return {
// Node to return focus to
node: menu && dojo.isDescendant(dijit._curFocus, menu.domNode) ? dijit._prevFocus : dijit._curFocus,
// Previously selected text
bookmark:
!dojo.withGlobal(openedForWindow||dojo.global, dijit.isCollapsed) ?
dojo.withGlobal(openedForWindow||dojo.global, dijit.getBookmark) :
null,
openedForWindow: openedForWindow
}; // Object
},
focus: function(/*Object || DomNode */ handle){
// summary:
// Sets the focused node and the selection according to argument.
// To set focus to an iframe's content, pass in the iframe itself.
// handle:
// object returned by get(), or a DomNode
if(!handle){ return; }
var node = "node" in handle ? handle.node : handle, // because handle is either DomNode or a composite object
bookmark = handle.bookmark,
openedForWindow = handle.openedForWindow;
// Set the focus
// Note that for iframe's we need to use the <iframe> to follow the parentNode chain,
// but we need to set focus to iframe.contentWindow
if(node){
var focusNode = (node.tagName.toLowerCase()=="iframe") ? node.contentWindow : node;
if(focusNode && focusNode.focus){
try{
// Gecko throws sometimes if setting focus is impossible,
// node not displayed or something like that
focusNode.focus();
}catch(e){/*quiet*/}
}
dijit._onFocusNode(node);
}
// set the selection
// do not need to restore if current selection is not empty
// (use keyboard to select a menu item)
if(bookmark && dojo.withGlobal(openedForWindow||dojo.global, dijit.isCollapsed)){
if(openedForWindow){
openedForWindow.focus();
}
try{
dojo.withGlobal(openedForWindow||dojo.global, dijit.moveToBookmark, null, [bookmark]);
}catch(e){
/*squelch IE internal error, see http://trac.dojotoolkit.org/ticket/1984 */
}
}
},
// _activeStack: Array
// List of currently active widgets (focused widget and it's ancestors)
_activeStack: [],
registerWin: function(/*Window?*/targetWindow){
// summary:
// Registers listeners on the specified window (either the main
// window or an iframe) to detect when the user has clicked somewhere.
// Anyone that creates an iframe should call this function.
if(!targetWindow){
targetWindow = window;
}
dojo.connect(targetWindow.document, "onmousedown", function(evt){
dijit._justMouseDowned = true;
setTimeout(function(){ dijit._justMouseDowned = false; }, 0);
dijit._onTouchNode(evt.target||evt.srcElement);
});
//dojo.connect(targetWindow, "onscroll", ???);
// Listen for blur and focus events on targetWindow's body
var body = targetWindow.document.body || targetWindow.document.getElementsByTagName("body")[0];
if(body){
if(dojo.isIE){
body.attachEvent('onactivate', function(evt){
if(evt.srcElement.tagName.toLowerCase() != "body"){
dijit._onFocusNode(evt.srcElement);
}
});
body.attachEvent('ondeactivate', function(evt){ dijit._onBlurNode(evt.srcElement); });
}else{
body.addEventListener('focus', function(evt){ dijit._onFocusNode(evt.target); }, true);
body.addEventListener('blur', function(evt){ dijit._onBlurNode(evt.target); }, true);
}
}
body = null; // prevent memory leak (apparent circular reference via closure)
},
_onBlurNode: function(/*DomNode*/ node){
// summary:
// Called when focus leaves a node.
// Usually ignored, _unless_ it *isn't* follwed by touching another node,
// which indicates that we tabbed off the last field on the page,
// in which case every widget is marked inactive
dijit._prevFocus = dijit._curFocus;
dijit._curFocus = null;
if(dijit._justMouseDowned){
// the mouse down caused a new widget to be marked as active; this blur event
// is coming late, so ignore it.
return;
}
// if the blur event isn't followed by a focus event then mark all widgets as inactive.
if(dijit._clearActiveWidgetsTimer){
clearTimeout(dijit._clearActiveWidgetsTimer);
}
dijit._clearActiveWidgetsTimer = setTimeout(function(){
delete dijit._clearActiveWidgetsTimer;
dijit._setStack([]);
dijit._prevFocus = null;
}, 100);
},
_onTouchNode: function(/*DomNode*/ node){
// summary:
// Callback when node is focused or mouse-downed
// ignore the recent blurNode event
if(dijit._clearActiveWidgetsTimer){
clearTimeout(dijit._clearActiveWidgetsTimer);
delete dijit._clearActiveWidgetsTimer;
}
// compute stack of active widgets (ex: ComboButton --> Menu --> MenuItem)
var newStack=[];
try{
while(node){
if(node.dijitPopupParent){
node=dijit.byId(node.dijitPopupParent).domNode;
}else if(node.tagName && node.tagName.toLowerCase()=="body"){
// is this the root of the document or just the root of an iframe?
if(node===dojo.body()){
// node is the root of the main document
break;
}
// otherwise, find the iframe this node refers to (can't access it via parentNode,
// need to do this trick instead). window.frameElement is supported in IE/FF/Webkit
node=dijit.getDocumentWindow(node.ownerDocument).frameElement;
}else{
var id = node.getAttribute && node.getAttribute("widgetId");
if(id){
newStack.unshift(id);
}
node=node.parentNode;
}
}
}catch(e){ /* squelch */ }
dijit._setStack(newStack);
},
_onFocusNode: function(/*DomNode*/ node){
// summary
// Callback when node is focused
if(node && node.tagName && node.tagName.toLowerCase() == "body"){
return;
}
dijit._onTouchNode(node);
if(node==dijit._curFocus){ return; }
if(dijit._curFocus){
dijit._prevFocus = dijit._curFocus;
}
dijit._curFocus = node;
dojo.publish("focusNode", [node]);
},
_setStack: function(newStack){
// summary
// The stack of active widgets has changed. Send out appropriate events and record new stack
var oldStack = dijit._activeStack;
dijit._activeStack = newStack;
// compare old stack to new stack to see how many elements they have in common
for(var nCommon=0; nCommon<Math.min(oldStack.length, newStack.length); nCommon++){
if(oldStack[nCommon] != newStack[nCommon]){
break;
}
}
// for all elements that have gone out of focus, send blur event
for(var i=oldStack.length-1; i>=nCommon; i--){
var widget = dijit.byId(oldStack[i]);
if(widget){
widget._focused = false;
widget._hasBeenBlurred = true;
if(widget._onBlur){
widget._onBlur();
}
if (widget._setStateClass){
widget._setStateClass();
}
dojo.publish("widgetBlur", [widget]);
}
}
// for all element that have come into focus, send focus event
for(i=nCommon; i<newStack.length; i++){
widget = dijit.byId(newStack[i]);
if(widget){
widget._focused = true;
if(widget._onFocus){
widget._onFocus();
}
if (widget._setStateClass){
widget._setStateClass();
}
dojo.publish("widgetFocus", [widget]);
}
}
}
});
// register top window and all the iframes it contains
dojo.addOnLoad(dijit.registerWin);
