// widget_foreach.ysl2
widget_desc("ForEach") {
longdesc
||
ForEach widget is used to span a small set of widget over a larger set of
repeated HMI_NODEs.
Idea is somewhat similar to relative page, but it all happens inside the
ForEach widget, no page involved.
Together with relative Jump widgets it can be used to build a menu to reach
relative pages covering many identical HMI_NODES siblings.
ForEach widget takes a HMI_CLASS name as argument and a HMI_NODE path as
variable.
Direct sub-elements can be either groups of widget to be spanned, labeled
"ClassName:offset", or buttons to control the spanning, labeled
"ClassName:+/-number".
In case of "ClassName:offset", offset for first element is 1.
||
shortdesc > span widgets over a set of repeated HMI_NODEs
arg name="class_name" accepts="string" > HMI_CLASS name
path name="root" accepts="HMI_NODE" > where to find HMI_NODEs whose HMI_CLASS is class_name
}
widget_defs("ForEach") {
if "count(path) < 1" error > ForEach widget «$hmi_element/@id» must have one HMI path given.
if "count(arg) != 1" error > ForEach widget «$hmi_element/@id» must have one argument given : a class name.
const "class","arg[1]/@value";
const "base_path","path/@value";
const "hmi_index_base", "$indexed_hmitree/*[@hmipath = $base_path]";
const "hmi_tree_base", "$hmitree/descendant-or-self::*[@path = $hmi_index_base/@path]";
const "hmi_tree_items", "$hmi_tree_base/*[@class = $class]";
const "hmi_index_items", "$indexed_hmitree/*[@path = $hmi_tree_items/@path]";
const "items_paths", "$hmi_index_items/@hmipath";
| index_pool: [
foreach "$hmi_index_items" {
| «@index»`if "position()!=last()" > ,`
}
| ],
| init: function() {
const "prefix","concat($class,':')";
const "buttons_regex","concat('^',$prefix,'[+\-][0-9]+')";
const "buttons", "$hmi_element/*[regexp:test(@inkscape:label, $buttons_regex)]";
foreach "$buttons" {
const "op","substring-after(@inkscape:label, $prefix)";
| id("«@id»").setAttribute("onclick", "hmi_widgets['«$hmi_element/@id»'].on_click('«$op»', evt)");
}
|
| this.items = [
const "items_regex","concat('^',$prefix,'[0-9]+')";
const "unordered_items","$hmi_element//*[regexp:test(@inkscape:label, $items_regex)]";
foreach "$unordered_items" {
const "elt_label","concat($prefix, string(position()))";
const "elt","$unordered_items[@inkscape:label = $elt_label]";
const "pos","position()";
const "item_path", "$items_paths[$pos]";
| [ /* item="«$elt_label»" path="«$item_path»" */
if "count($elt)=0" error > Missing item labeled «$elt_label» in ForEach widget «$hmi_element/@id»
if "count($elt)>1" error > Duplicate item labeled «$elt_label» in ForEach widget «$hmi_element/@id»
foreach "func:refered_elements($elt)[@id = $hmi_elements/@id][not(@id = $elt/@id)]" {
if "not(func:is_descendant_path(func:widget(@id)/path/@value, $item_path))"
error > Widget id="«@id»" label="«@inkscape:label»" is having wrong path. Accroding to ForEach widget ancestor id="«$hmi_element/@id»", path should be descendant of "«$item_path»".
| hmi_widgets["«@id»"]`if "position()!=last()" > ,`
}
| ]`if "position()!=last()" > ,`
}
| ]
| },
| range: «count($hmi_index_items)»,
| size: «count($unordered_items)»,
| position: 0,
}
widget_class("ForEach")
||
items_subscribed = false;
unsub_items(){
if(this.items_subscribed){
for(let item of this.items){
for(let widget of item) {
widget.unsub();
}
}
this.items_subscribed = false;
}
}
unsub(){
super.unsub()
this.unsub_items();
}
sub_items(){
if(!this.items_subscribed){
for(let i = 0; i < this.size; i++) {
let item = this.items[i];
let orig_item_index = this.index_pool[i];
let item_index = this.index_pool[i+this.position];
let item_index_offset = item_index - orig_item_index;
if(this.relativeness[0])
item_index_offset += this.offset;
for(let widget of item) {
/* all variables of all widgets in a ForEach are all relative.
Really.
TODO: allow absolute variables in ForEach widgets
*/
widget.sub(item_index_offset, widget.indexes.map(_=>true));
}
}
}
}
sub(new_offset, relativeness, container_id){
let position_given = this.indexes.length > 2;
// sub() will call apply_cache() and then dispatch()
// undefining position forces dispatch() to call apply_position()
if(position_given)
this.position = undefined;
super.sub(new_offset, relativeness, container_id);
// if position isn't given as a variable
// dispatch() to call apply_position() aren't called
// and items must be subscibed now.
if(!position_given)
this.sub_items();
// as soon as subribed apply range and size once for all
this.apply_hmi_value(1, this.range);
this.apply_hmi_value(3, this.size);
}
apply_position(new_position){
let old_position = this.position;
let limited_position = Math.round(Math.max(Math.min(new_position, this.range - this.size), 0));
if(this.position == limited_position){
return false;
}
this.unsub_items();
this.position = limited_position;
this.sub_items();
request_subscriptions_update();
jumps_need_update = true;
this.request_animate();
return true;
}
on_click(opstr, evt) {
let new_position = eval(String(this.position)+opstr);
if(new_position + this.size > this.range) {
if(this.position + this.size == this.range)
new_position = 0;
else
new_position = this.range - this.size;
} else if(new_position < 0) {
if(this.position == 0)
new_position = this.range - this.size;
else
new_position = 0;
}
if(this.apply_position(new_position)){
this.apply_hmi_value(2, this.position);
}
}
dispatch(value, oldval, index) {
// Only care about position, others are constants
if(index == 2){
this.apply_position(value);
if(this.position != value){
// widget refused or apply different value, force it back
this.apply_hmi_value(2, this.position);
}
}
}
||