Merge pull request #148 from iangray001/chunkupdates2

Make initial UI update reliable (and 4 small fixes)

README.md

@@ -259,6 +259,12 @@ A number box needs to have a min and a max value. To set it up just use:
 
 `ESPUI.number("Numbertest", &numberCall, ControlColor::Alizarin, 5, 0, 10);`
 
+Note that HTML number boxes will respect their min and max when the user
+clicks the up and down arrows, but it is possible on most clients to simply type 
+any number in. As with all user input, numbers should be validated in callback code
+because all client side checks can be skipped. If any value from the UI might
+cause a problem, validate it.
+
 #### Text Input
 
 ![text](https://github.com/s00500/ESPUI/blob/master/docs/ui_text.png)
@@ -267,6 +273,17 @@ The textinput works very similar like the number input but with a string. You
 can enter a String into it and when you are done with your change it is sent to
 the ESP.
 
+If you attach a Max control to the text input then a max length will be applied
+to the control. 
+
+```
+ text = ESPUI.text("Label", callback, ControlColor::Dark, "Initial value");
+ ESPUI.addControl(ControlType::Max, "", "32", ControlColor::None, text);
+```
+
+However even with a set maximum length, user input should still be validated 
+because it is easy to bypass client-side checks. Never trust user input.
+
 #### Graph
 
 ![graph](https://github.com/s00500/ESPUI/blob/master/docs/ui_graph.png)

data/js/controls.js

@@ -102,6 +102,7 @@ function colorClass(colorId) {
     case C_ALIZARIN:
       return "alizarin";
 
+    case C_DARK:
     case C_NONE:
       return "dark";
     default:
@@ -252,6 +253,13 @@ function start() {
           };
           handleEvent(fauxEvent);
         });
+
+        //If there are more elements in the complete UI, then request them
+        //Note: we subtract 1 from data.controls.length because the controls always
+        //includes the title element
+        if(data.totalcontrols > (data.controls.length - 1)) {
+          websock.send("uiok:" + (data.controls.length - 1));
+        }
         break;
 
       case UI_EXTEND_GUI:
@@ -261,6 +269,11 @@ function start() {
           };
           handleEvent(fauxEvent);
         });
+
+        //Do we need to keep requesting more UI elements?
+        if(data.totalcontrols > data.startindex + (data.controls.length - 1)) {
+          websock.send("uiok:" + (data.startindex + (data.controls.length - 1)));
+        }
         break;
       
       case UI_RELOAD:
@@ -428,7 +441,13 @@ function start() {
         if (data.parentControl) {
           var parent = $("#id" + data.parentControl + " input");
           if (parent.size()) {
-            parent.attr("max", data.value);
+            if(!parent.attr("type")) {
+              //type is not set so therefore it is a text input
+              parent.attr("maxlength", data.value);
+            } else {
+              //type might be range (slider) or number
+              parent.attr("max", data.value);
+            }
           }
         }
         break;
@@ -488,6 +507,7 @@ function start() {
         break;
 
       case UPDATE_SLIDER:
+        $("#sl" + data.id).attr("value", data.value)
         slider_move($("#id" + data.id), data.value, "100", false);
         if(data.hasOwnProperty('elementStyle')) {
           $("#sl" + data.id).attr("style", data.elementStyle);
@@ -516,6 +536,12 @@ function start() {
         break;
 
       case UPDATE_BUTTON:
+        $("#btn" + data.id).val(data.value);
+        if(data.hasOwnProperty('elementStyle')) {
+          $("#btn" + data.id).attr("style", data.elementStyle);
+        }
+        break;
+      
       case UPDATE_PAD:
       case UPDATE_CPAD:
         break;
@@ -565,6 +591,10 @@ function start() {
 function sliderchange(number) {
   var val = $("#sl" + number).val();
   websock.send("slvalue:" + val + ":" + number);
+
+  $(".range-slider__range").each(function(){ 
+    $(this).attr("value", $(this)[0].value);
+  });
 }
 
 function numberchange(number) {
@@ -619,7 +649,7 @@ function padclick(type, number, isdown) {
 
 function switcher(number, state) {
   if (state == null) {
-    if ($("#s" + number).is(":checked")) {
+    if (!$("#sl" + number).hasClass("checked")) {
       websock.send("sactive:" + number);
       $("#sl" + number).addClass("checked");
     } else {
@@ -686,7 +716,7 @@ var addToHTML = function(data) {
       case UI_ACCEL:
         html = "<div id='id" + data.id + "' " + panelStyle + " class='two columns " + panelwide + " card tcenter " +
         colorClass(data.color) + "'><h5>" + data.label + "</h5><hr/>" +
-        elementHTML(data.type, data.id, data.value, elementStyle) +
+        elementHTML(data.type, data.id, data.value, data.label, elementStyle) +
         "</div>";
         break;
       case UI_SEPARATOR:
@@ -700,11 +730,11 @@ var addToHTML = function(data) {
   } else {
     //We are adding to an existing panel so we only need the HTML for the element
     var parent = $("#id" + data.parentControl);
-    parent.append(elementHTML(data.type, data.id, data.value, elementStyle));
+    parent.append(elementHTML(data.type, data.id, data.value, data.label, elementStyle));
   }
 }
 
-var elementHTML = function(type, id, value, elementStyle) {
+var elementHTML = function(type, id, value, label, elementStyle) {
   switch(type) {
     case UI_LABEL:
       return "<span id='l" + id + "' " + elementStyle + 

data/js/controls.min.js

@@ -1,4 +1,4 @@
-const UI_INITIAL_GUI=200;const UI_RELOAD=201;const UPDATE_OFFSET=100;const UI_EXTEND_GUI=210;const UI_TITEL=0;const UI_PAD=1;const UPDATE_PAD=101;const UI_CPAD=2;const UPDATE_CPAD=102;const UI_BUTTON=3;const UPDATE_BUTTON=103;const UI_LABEL=4;const UPDATE_LABEL=104;const UI_SWITCHER=5;const UPDATE_SWITCHER=105;const UI_SLIDER=6;const UPDATE_SLIDER=106;const UI_NUMBER=7;const UPDATE_NUMBER=107;const UI_TEXT_INPUT=8;const UPDATE_TEXT_INPUT=108;const UI_GRAPH=9;const ADD_GRAPH_POINT=10;const CLEAR_GRAPH=109;const UI_TAB=11;const UPDATE_TAB=111;const UI_SELECT=12;const UPDATE_SELECT=112;const UI_OPTION=13;const UPDATE_OPTION=113;const UI_MIN=14;const UPDATE_MIN=114;const UI_MAX=15;const UPDATE_MAX=115;const UI_STEP=16;const UPDATE_STEP=116;const UI_GAUGE=17;const UPDATE_GAUGE=117;const UI_ACCEL=18;const UPDATE_ACCEL=118;const UI_SEPARATOR=19;const UPDATE_SEPARATOR=119;const UP=0;const DOWN=1;const LEFT=2;const RIGHT=3;const CENTER=4;const C_TURQUOISE=0;const C_EMERALD=1;const C_PETERRIVER=2;const C_WETASPHALT=3;const C_SUNFLOWER=4;const C_CARROT=5;const C_ALIZARIN=6;const C_DARK=7;const C_NONE=255;var graphData=new Array();var hasAccel=false;var sliderContinuous=false;function colorClass(colorId){colorId=Number(colorId);switch(colorId){case C_TURQUOISE:return"turquoise";case C_EMERALD:return"emerald";case C_PETERRIVER:return"peterriver";case C_WETASPHALT:return"wetasphalt";case C_SUNFLOWER:return"sunflower";case C_CARROT:return"carrot";case C_ALIZARIN:return"alizarin";case C_NONE:return"dark";default:return"";}}
+const UI_INITIAL_GUI=200;const UI_RELOAD=201;const UPDATE_OFFSET=100;const UI_EXTEND_GUI=210;const UI_TITEL=0;const UI_PAD=1;const UPDATE_PAD=101;const UI_CPAD=2;const UPDATE_CPAD=102;const UI_BUTTON=3;const UPDATE_BUTTON=103;const UI_LABEL=4;const UPDATE_LABEL=104;const UI_SWITCHER=5;const UPDATE_SWITCHER=105;const UI_SLIDER=6;const UPDATE_SLIDER=106;const UI_NUMBER=7;const UPDATE_NUMBER=107;const UI_TEXT_INPUT=8;const UPDATE_TEXT_INPUT=108;const UI_GRAPH=9;const ADD_GRAPH_POINT=10;const CLEAR_GRAPH=109;const UI_TAB=11;const UPDATE_TAB=111;const UI_SELECT=12;const UPDATE_SELECT=112;const UI_OPTION=13;const UPDATE_OPTION=113;const UI_MIN=14;const UPDATE_MIN=114;const UI_MAX=15;const UPDATE_MAX=115;const UI_STEP=16;const UPDATE_STEP=116;const UI_GAUGE=17;const UPDATE_GAUGE=117;const UI_ACCEL=18;const UPDATE_ACCEL=118;const UI_SEPARATOR=19;const UPDATE_SEPARATOR=119;const UP=0;const DOWN=1;const LEFT=2;const RIGHT=3;const CENTER=4;const C_TURQUOISE=0;const C_EMERALD=1;const C_PETERRIVER=2;const C_WETASPHALT=3;const C_SUNFLOWER=4;const C_CARROT=5;const C_ALIZARIN=6;const C_DARK=7;const C_NONE=255;var graphData=new Array();var hasAccel=false;var sliderContinuous=false;function colorClass(colorId){colorId=Number(colorId);switch(colorId){case C_TURQUOISE:return"turquoise";case C_EMERALD:return"emerald";case C_PETERRIVER:return"peterriver";case C_WETASPHALT:return"wetasphalt";case C_SUNFLOWER:return"sunflower";case C_CARROT:return"carrot";case C_ALIZARIN:return"alizarin";case C_DARK:case C_NONE:return"dark";default:return"";}}
 var websock;var websockConnected=false;function requestOrientationPermission(){}
 function saveGraphData(){localStorage.setItem("espuigraphs",JSON.stringify(graphData));}
 function restoreGraphData(id){var savedData=localStorage.getItem("espuigraphs",graphData);if(savedData!=null){savedData=JSON.parse(savedData);return savedData[id];}
@@ -8,7 +8,9 @@ function conStatusError(){websockConnected=false;$("#conStatus").removeClass("co
 function handleVisibilityChange(){if(!websockConnected&&!document.hidden){restart();}}
 function start(){document.addEventListener("visibilitychange",handleVisibilityChange,false);if(window.location.port!=""||window.location.port!=80||window.location.port!=443){websock=new WebSocket("ws://"+window.location.hostname+":"+window.location.port+"/ws");}else{websock=new WebSocket("ws://"+window.location.hostname+"/ws");}
 websock.onopen=function(evt){console.log("websock open");$("#conStatus").addClass("color-green");$("#conStatus").text("Connected");websockConnected=true;};websock.onclose=function(evt){console.log("websock close");conStatusError();};websock.onerror=function(evt){console.log(evt);conStatusError();};var handleEvent=function(evt){console.log(evt);var data=JSON.parse(evt.data);var e=document.body;var center="";switch(data.type){case UI_INITIAL_GUI:$("#row").html("");$("#tabsnav").html("");$("#tabscontent").html("");if(data.sliderContinuous){sliderContinuous=data.sliderContinuous;}
-data.controls.forEach(element=>{var fauxEvent={data:JSON.stringify(element),};handleEvent(fauxEvent);});break;case UI_EXTEND_GUI:data.controls.forEach(element=>{var fauxEvent={data:JSON.stringify(element),};handleEvent(fauxEvent);});break;case UI_RELOAD:window.location.reload();break;case UI_TITEL:document.title=data.label;$("#mainHeader").html(data.label);break;case UI_LABEL:case UI_NUMBER:case UI_TEXT_INPUT:case UI_SELECT:case UI_GAUGE:case UI_SEPARATOR:if(data.visible)addToHTML(data);break;case UI_BUTTON:if(data.visible){addToHTML(data);$("#btn"+data.id).on({touchstart:function(e){e.preventDefault();buttonclick(data.id,true);},touchend:function(e){e.preventDefault();buttonclick(data.id,false);},});}
+data.controls.forEach(element=>{var fauxEvent={data:JSON.stringify(element),};handleEvent(fauxEvent);});if(data.totalcontrols>(data.controls.length-1)){websock.send("uiok:"+(data.controls.length-1));}
+break;case UI_EXTEND_GUI:data.controls.forEach(element=>{var fauxEvent={data:JSON.stringify(element),};handleEvent(fauxEvent);});if(data.totalcontrols>data.startindex+(data.controls.length-1)){websock.send("uiok:"+(data.startindex+(data.controls.length-1)));}
+break;case UI_RELOAD:window.location.reload();break;case UI_TITEL:document.title=data.label;$("#mainHeader").html(data.label);break;case UI_LABEL:case UI_NUMBER:case UI_TEXT_INPUT:case UI_SELECT:case UI_GAUGE:case UI_SEPARATOR:if(data.visible)addToHTML(data);break;case UI_BUTTON:if(data.visible){addToHTML(data);$("#btn"+data.id).on({touchstart:function(e){e.preventDefault();buttonclick(data.id,true);},touchend:function(e){e.preventDefault();buttonclick(data.id,false);},});}
 break;case UI_SWITCHER:if(data.visible){addToHTML(data);switcher(data.id,data.value);}
 break;case UI_CPAD:case UI_PAD:if(data.visible){addToHTML(data);$("#pf"+data.id).on({touchstart:function(e){e.preventDefault();padclick(UP,data.id,true);},touchend:function(e){e.preventDefault();padclick(UP,data.id,false);},});$("#pl"+data.id).on({touchstart:function(e){e.preventDefault();padclick(LEFT,data.id,true);},touchend:function(e){e.preventDefault();padclick(LEFT,data.id,false);},});$("#pr"+data.id).on({touchstart:function(e){e.preventDefault();padclick(RIGHT,data.id,true);},touchend:function(e){e.preventDefault();padclick(RIGHT,data.id,false);},});$("#pb"+data.id).on({touchstart:function(e){e.preventDefault();padclick(DOWN,data.id,true);},touchend:function(e){e.preventDefault();padclick(DOWN,data.id,false);},});$("#pc"+data.id).on({touchstart:function(e){e.preventDefault();padclick(CENTER,data.id,true);},touchend:function(e){e.preventDefault();padclick(CENTER,data.id,false);},});}
 break;case UI_SLIDER:if(data.visible){addToHTML(data);rangeSlider(!sliderContinuous);}
@@ -24,37 +26,39 @@ data.selected+
 data.label+
 "</option>");}
 break;case UI_MIN:if(data.parentControl){var parent=$("#id"+data.parentControl+" input");if(parent.size()){parent.attr("min",data.value);}}
-break;case UI_MAX:if(data.parentControl){var parent=$("#id"+data.parentControl+" input");if(parent.size()){parent.attr("max",data.value);}}
+break;case UI_MAX:if(data.parentControl){var parent=$("#id"+data.parentControl+" input");if(parent.size()){if(!parent.attr("type")){parent.attr("maxlength",data.value);}else{parent.attr("max",data.value);}}}
 break;case UI_STEP:if(data.parentControl){var parent=$("#id"+data.parentControl+" input");if(parent.size()){parent.attr("step",data.value);}}
 break;case UI_GRAPH:if(data.visible){addToHTML(data);graphData[data.id]=restoreGraphData(data.id);renderGraphSvg(graphData[data.id],"graph"+data.id);}
 break;case ADD_GRAPH_POINT:var ts=Math.round(new Date().getTime()/1000);graphData[data.id].push({x:ts,y:data.value});saveGraphData();renderGraphSvg(graphData[data.id],"graph"+data.id);break;case CLEAR_GRAPH:graphData[data.id]=[];saveGraphData();renderGraphSvg(graphData[data.id],"graph"+data.id);break;case UI_ACCEL:if(hasAccel)break;hasAccel=true;if(data.visible){addToHTML(data);requestOrientationPermission();}
 break;case UPDATE_LABEL:$("#l"+data.id).html(data.value);if(data.hasOwnProperty('elementStyle')){$("#l"+data.id).attr("style",data.elementStyle);}
 break;case UPDATE_SWITCHER:switcher(data.id,data.value=="0"?0:1);if(data.hasOwnProperty('elementStyle')){$("#sl"+data.id).attr("style",data.elementStyle);}
-break;case UPDATE_SLIDER:slider_move($("#id"+data.id),data.value,"100",false);if(data.hasOwnProperty('elementStyle')){$("#sl"+data.id).attr("style",data.elementStyle);}
+break;case UPDATE_SLIDER:$("#sl"+data.id).attr("value",data.value)
+slider_move($("#id"+data.id),data.value,"100",false);if(data.hasOwnProperty('elementStyle')){$("#sl"+data.id).attr("style",data.elementStyle);}
 break;case UPDATE_NUMBER:$("#num"+data.id).val(data.value);if(data.hasOwnProperty('elementStyle')){$("#num"+data.id).attr("style",data.elementStyle);}
 break;case UPDATE_TEXT_INPUT:$("#text"+data.id).val(data.value);if(data.hasOwnProperty('elementStyle')){$("#text"+data.id).attr("style",data.elementStyle);}
 break;case UPDATE_SELECT:$("#select"+data.id).val(data.value);if(data.hasOwnProperty('elementStyle')){$("#select"+data.id).attr("style",data.elementStyle);}
-break;case UPDATE_BUTTON:case UPDATE_PAD:case UPDATE_CPAD:break;case UPDATE_GAUGE:$("#gauge"+data.id).val(data.value);if(data.hasOwnProperty('elementStyle')){$("#gauge"+data.id).attr("style",data.elementStyle);}
+break;case UPDATE_BUTTON:$("#btn"+data.id).val(data.value);if(data.hasOwnProperty('elementStyle')){$("#btn"+data.id).attr("style",data.elementStyle);}
+break;case UPDATE_PAD:case UPDATE_CPAD:break;case UPDATE_GAUGE:$("#gauge"+data.id).val(data.value);if(data.hasOwnProperty('elementStyle')){$("#gauge"+data.id).attr("style",data.elementStyle);}
 break;case UPDATE_ACCEL:break;default:console.error("Unknown type or event");break;}
 if(data.type>=UPDATE_OFFSET&&data.type<UI_INITIAL_GUI){var element=$("#id"+data.id);if(data.hasOwnProperty('panelStyle')){$("#id"+data.id).attr("style",data.panelStyle);}
 if(data.type==UPDATE_SLIDER){element.removeClass("slider-turquoise slider-emerald slider-peterriver slider-wetasphalt slider-sunflower slider-carrot slider-alizarin");element.addClass("slider-"+colorClass(data.color));}else{element.removeClass("turquoise emerald peterriver wetasphalt sunflower carrot alizarin");element.addClass(colorClass(data.color));}}
 $(".range-slider__range").each(function(){$(this)[0].value=$(this).attr("value");$(this).next().html($(this).attr("value"));});};websock.onmessage=handleEvent;}
-function sliderchange(number){var val=$("#sl"+number).val();websock.send("slvalue:"+val+":"+number);}
+function sliderchange(number){var val=$("#sl"+number).val();websock.send("slvalue:"+val+":"+number);$(".range-slider__range").each(function(){$(this).attr("value",$(this)[0].value);});}
 function numberchange(number){var val=$("#num"+number).val();websock.send("nvalue:"+val+":"+number);}
 function textchange(number){var val=$("#text"+number).val();websock.send("tvalue:"+val+":"+number);}
 function tabclick(number){var val=$("#tab"+number).val();websock.send("tabvalue:"+val+":"+number);}
 function selectchange(number){var val=$("#select"+number).val();websock.send("svalue:"+val+":"+number);}
 function buttonclick(number,isdown){if(isdown)websock.send("bdown:"+number);else websock.send("bup:"+number);}
 function padclick(type,number,isdown){switch(type){case CENTER:if(isdown)websock.send("pcdown:"+number);else websock.send("pcup:"+number);break;case UP:if(isdown)websock.send("pfdown:"+number);else websock.send("pfup:"+number);break;case DOWN:if(isdown)websock.send("pbdown:"+number);else websock.send("pbup:"+number);break;case LEFT:if(isdown)websock.send("pldown:"+number);else websock.send("plup:"+number);break;case RIGHT:if(isdown)websock.send("prdown:"+number);else websock.send("prup:"+number);break;}}
-function switcher(number,state){if(state==null){if($("#s"+number).is(":checked")){websock.send("sactive:"+number);$("#sl"+number).addClass("checked");}else{websock.send("sinactive:"+number);$("#sl"+number).removeClass("checked");}}else if(state==1){$("#sl"+number).addClass("checked");$("#sl"+number).prop("checked",true);}else if(state==0){$("#sl"+number).removeClass("checked");$("#sl"+number).prop("checked",false);}}
+function switcher(number,state){if(state==null){if(!$("#sl"+number).hasClass("checked")){websock.send("sactive:"+number);$("#sl"+number).addClass("checked");}else{websock.send("sinactive:"+number);$("#sl"+number).removeClass("checked");}}else if(state==1){$("#sl"+number).addClass("checked");$("#sl"+number).prop("checked",true);}else if(state==0){$("#sl"+number).removeClass("checked");$("#sl"+number).prop("checked",false);}}
 var rangeSlider=function(isDiscrete){var range=$(".range-slider__range");var slidercb=function(){sliderchange($(this).attr("id").replace(/^\D+/g,""));};range.on({input:function(){$(this).next().html(this.value)}});range.each(function(){$(this).next().html(this.value);if($(this).attr("callbackSet")!="true"){if(!isDiscrete){$(this).on({input:slidercb});}else{$(this).on({change:slidercb});}
 $(this).attr("callbackSet","true");}});};var addToHTML=function(data){panelStyle=data.hasOwnProperty('panelStyle')?" style='"+data.panelStyle+"' ":"";elementStyle=data.hasOwnProperty('elementStyle')?" style='"+data.elementStyle+"' ":"";panelwide=data.hasOwnProperty('wide')?"wide":"";if(!data.hasOwnProperty('parentControl')||$("#tab"+data.parentControl).length>0){var parent=data.hasOwnProperty('parentControl')?$("#tab"+data.parentControl):$("#row");var html="";switch(data.type){case UI_LABEL:case UI_BUTTON:case UI_SWITCHER:case UI_CPAD:case UI_PAD:case UI_SLIDER:case UI_NUMBER:case UI_TEXT_INPUT:case UI_SELECT:case UI_GRAPH:case UI_GAUGE:case UI_ACCEL:html="<div id='id"+data.id+"' "+panelStyle+" class='two columns "+panelwide+" card tcenter "+
 colorClass(data.color)+"'><h5>"+data.label+"</h5><hr/>"+
-elementHTML(data.type,data.id,data.value,elementStyle)+
+elementHTML(data.type,data.id,data.value,data.label,elementStyle)+
 "</div>";break;case UI_SEPARATOR:html="<div id='id"+data.id+"' "+panelStyle+" class='sectionbreak columns'>"+
 "<h5>"+data.label+"</h5><hr/></div>";break;}
-parent.append(html);}else{var parent=$("#id"+data.parentControl);parent.append(elementHTML(data.type,data.id,data.value,elementStyle));}}
+parent.append(html);}else{var parent=$("#id"+data.parentControl);parent.append(elementHTML(data.type,data.id,data.value,data.label,elementStyle));}}
-var elementHTML=function(type,id,value,elementStyle){switch(type){case UI_LABEL:return"<span id='l"+id+"' "+elementStyle+
+var elementHTML=function(type,id,value,label,elementStyle){switch(type){case UI_LABEL:return"<span id='l"+id+"' "+elementStyle+
 " class='label label-wrap'>"+value+"</span>";case UI_BUTTON:return"<button id='btn"+id+"' "+elementStyle+
 " onmousedown='buttonclick("+id+", true)'"+
 " onmouseup='buttonclick("+id+", false)'>"+

src/ESPUI.cpp

@@ -422,7 +422,7 @@ void onWsEvent(
         }
 #endif
 
-        ESPUI.jsonDom(client);
+        ESPUI.jsonDom(0, client);
 
 #if defined(DEBUG_ESPUI)
         if (ESPUI.verbosity)
@@ -442,142 +442,149 @@ void onWsEvent(
             msg += (char)data[i];
         }
 
-        uint16_t id = msg.substring(msg.lastIndexOf(':') + 1).toInt();
+        if (msg.startsWith(F("uiok:")))
-
-#if defined(DEBUG_ESPUI)
-        if (ESPUI.verbosity >= Verbosity::VerboseJSON)
         {
-            Serial.print(F("WS rec: "));
+            int idx = msg.substring(msg.indexOf(':') + 1).toInt();
-            Serial.println(msg);
+            ESPUI.jsonDom(idx);
-            Serial.print(F("WS recognised ID: "));
+        } else 
-            Serial.println(id);
-        }
-#endif
-
-        Control* c = ESPUI.getControl(id);
-
-        if (c == nullptr)
         {
-#if defined(DEBUG_ESPUI)
+            uint16_t id = msg.substring(msg.lastIndexOf(':') + 1).toInt();
-            if (ESPUI.verbosity)
+
+    #if defined(DEBUG_ESPUI)
+            if (ESPUI.verbosity >= Verbosity::VerboseJSON)
             {
-                Serial.print(F("No control found for ID "));
+                Serial.print(F("WS rec: "));
+                Serial.println(msg);
+                Serial.print(F("WS recognised ID: "));
                 Serial.println(id);
             }
-#endif
+    #endif
 
-            return;
+            Control* c = ESPUI.getControl(id);
-        }
 
-        if (c->callback == nullptr)
+            if (c == nullptr)
-        {
-#if defined(DEBUG_ESPUI)
-            if (ESPUI.verbosity)
             {
-                Serial.print(F("No callback found for ID "));
+    #if defined(DEBUG_ESPUI)
-                Serial.println(id);
+                if (ESPUI.verbosity)
+                {
+                    Serial.print(F("No control found for ID "));
+                    Serial.println(id);
+                }
+    #endif
+
+                return;
             }
-#endif
 
-            return;
+            if (c->callback == nullptr)
-        }
-
-        if (msg.startsWith(F("bdown:")))
-        {
-            c->callback(c, B_DOWN);
-        }
-        else if (msg.startsWith(F("bup:")))
-        {
-            c->callback(c, B_UP);
-        }
-        else if (msg.startsWith(F("pfdown:")))
-        {
-            c->callback(c, P_FOR_DOWN);
-        }
-        else if (msg.startsWith(F("pfup:")))
-        {
-            c->callback(c, P_FOR_UP);
-        }
-        else if (msg.startsWith(F("pldown:")))
-        {
-            c->callback(c, P_LEFT_DOWN);
-        }
-        else if (msg.startsWith(F("plup:")))
-        {
-            c->callback(c, P_LEFT_UP);
-        }
-        else if (msg.startsWith(F("prdown:")))
-        {
-            c->callback(c, P_RIGHT_DOWN);
-        }
-        else if (msg.startsWith(F("prup:")))
-        {
-            c->callback(c, P_RIGHT_UP);
-        }
-        else if (msg.startsWith(F("pbdown:")))
-        {
-            c->callback(c, P_BACK_DOWN);
-        }
-        else if (msg.startsWith(F("pbup:")))
-        {
-            c->callback(c, P_BACK_UP);
-        }
-        else if (msg.startsWith(F("pcdown:")))
-        {
-            c->callback(c, P_CENTER_DOWN);
-        }
-        else if (msg.startsWith(F("pcup:")))
-        {
-            c->callback(c, P_CENTER_UP);
-        }
-        else if (msg.startsWith(F("sactive:")))
-        {
-            c->value = "1";
-            ESPUI.updateControl(c, client->id());
-            c->callback(c, S_ACTIVE);
-        }
-        else if (msg.startsWith(F("sinactive:")))
-        {
-            c->value = "0";
-            ESPUI.updateControl(c, client->id());
-            c->callback(c, S_INACTIVE);
-        }
-        else if (msg.startsWith(F("slvalue:")))
-        {
-            c->value = msg.substring(msg.indexOf(':') + 1, msg.lastIndexOf(':'));
-            ESPUI.updateControl(c, client->id());
-            c->callback(c, SL_VALUE);
-        }
-        else if (msg.startsWith(F("nvalue:")))
-        {
-            c->value = msg.substring(msg.indexOf(':') + 1, msg.lastIndexOf(':'));
-            ESPUI.updateControl(c, client->id());
-            c->callback(c, N_VALUE);
-        }
-        else if (msg.startsWith(F("tvalue:")))
-        {
-            c->value = msg.substring(msg.indexOf(':') + 1, msg.lastIndexOf(':'));
-            ESPUI.updateControl(c, client->id());
-            c->callback(c, T_VALUE);
-        }
-        else if (msg.startsWith("tabvalue:"))
-        {
-            c->callback(c, client->id());
-        }
-        else if (msg.startsWith(F("svalue:")))
-        {
-            c->value = msg.substring(msg.indexOf(':') + 1, msg.lastIndexOf(':'));
-            ESPUI.updateControl(c, client->id());
-            c->callback(c, S_VALUE);
-        }
-        else
-        {
-#if defined(DEBUG_ESPUI)
-            if (ESPUI.verbosity)
             {
-                Serial.println(F("Malformated message from the websocket"));
+    #if defined(DEBUG_ESPUI)
+                if (ESPUI.verbosity)
+                {
+                    Serial.print(F("No callback found for ID "));
+                    Serial.println(id);
+                }
+    #endif
+
+                return;
+            }
+
+            if (msg.startsWith(F("bdown:")))
+            {
+                c->callback(c, B_DOWN);
+            }
+            else if (msg.startsWith(F("bup:")))
+            {
+                c->callback(c, B_UP);
+            }
+            else if (msg.startsWith(F("pfdown:")))
+            {
+                c->callback(c, P_FOR_DOWN);
+            }
+            else if (msg.startsWith(F("pfup:")))
+            {
+                c->callback(c, P_FOR_UP);
+            }
+            else if (msg.startsWith(F("pldown:")))
+            {
+                c->callback(c, P_LEFT_DOWN);
+            }
+            else if (msg.startsWith(F("plup:")))
+            {
+                c->callback(c, P_LEFT_UP);
+            }
+            else if (msg.startsWith(F("prdown:")))
+            {
+                c->callback(c, P_RIGHT_DOWN);
+            }
+            else if (msg.startsWith(F("prup:")))
+            {
+                c->callback(c, P_RIGHT_UP);
+            }
+            else if (msg.startsWith(F("pbdown:")))
+            {
+                c->callback(c, P_BACK_DOWN);
+            }
+            else if (msg.startsWith(F("pbup:")))
+            {
+                c->callback(c, P_BACK_UP);
+            }
+            else if (msg.startsWith(F("pcdown:")))
+            {
+                c->callback(c, P_CENTER_DOWN);
+            }
+            else if (msg.startsWith(F("pcup:")))
+            {
+                c->callback(c, P_CENTER_UP);
+            }
+            else if (msg.startsWith(F("sactive:")))
+            {
+                c->value = "1";
+                ESPUI.updateControl(c, client->id());
+                c->callback(c, S_ACTIVE);
+            }
+            else if (msg.startsWith(F("sinactive:")))
+            {
+                c->value = "0";
+                ESPUI.updateControl(c, client->id());
+                c->callback(c, S_INACTIVE);
+            }
+            else if (msg.startsWith(F("slvalue:")))
+            {
+                c->value = msg.substring(msg.indexOf(':') + 1, msg.lastIndexOf(':'));
+                ESPUI.updateControl(c, client->id());
+                c->callback(c, SL_VALUE);
+            }
+            else if (msg.startsWith(F("nvalue:")))
+            {
+                c->value = msg.substring(msg.indexOf(':') + 1, msg.lastIndexOf(':'));
+                ESPUI.updateControl(c, client->id());
+                c->callback(c, N_VALUE);
+            }
+            else if (msg.startsWith(F("tvalue:")))
+            {
+                c->value = msg.substring(msg.indexOf(':') + 1, msg.lastIndexOf(':'));
+                ESPUI.updateControl(c, client->id());
+                c->callback(c, T_VALUE);
+            }
+            else if (msg.startsWith("tabvalue:"))
+            {
+                c->callback(c, client->id());
+            }
+            else if (msg.startsWith(F("svalue:")))
+            {
+                c->value = msg.substring(msg.indexOf(':') + 1, msg.lastIndexOf(':'));
+                ESPUI.updateControl(c, client->id());
+                c->callback(c, S_VALUE);
+            }
+            else
+            {
+    #if defined(DEBUG_ESPUI)
+                if (ESPUI.verbosity)
+                {
+                    Serial.println(F("Malformated message from the websocket"));
+                }
+    #endif
             }
-#endif
         }
     }
     break;
@@ -608,6 +615,8 @@ uint16_t ESPUIClass::addControl(ControlType type, const char* label, const Strin
         iterator->next = control;
     }
 
+    this->controlCount++;
+
     return control->id;
 }
 
@@ -622,13 +631,14 @@ bool ESPUIClass::removeControl(uint16_t id, bool force_reload_ui)
     {
         this->controls = it->next;
         delete it;
+        this->controlCount--;
         if (force_reload_ui)
         {
             jsonReload();
         }
         else
         {
-            jsonDom();
+            jsonDom(0);
         }
         return true;
     }
@@ -644,13 +654,14 @@ bool ESPUIClass::removeControl(uint16_t id, bool force_reload_ui)
     {
         it->next = it_next->next;
         delete it_next;
+        this->controlCount--;
         if (force_reload_ui)
         {
             jsonReload();
         }
         else
         {
-            jsonDom(); // resends to all
+            jsonDom(0); // resends to all
         }
         return true;
     }
@@ -752,6 +763,11 @@ void ESPUIClass::updateControl(Control* control, int clientId)
         return;
     }
 
+    if (this->ws == nullptr)
+    {
+        return;
+    }
+
     String json;
     DynamicJsonDocument document(jsonUpdateDocumentSize);
     JsonObject root = document.to<JsonObject>();
@@ -977,61 +993,79 @@ void ESPUIClass::addGraphPoint(uint16_t id, int nValue, int clientId)
         tryId++;
     }
 }
+
 /*
-Convert & Transfer Arduino elements to JSON elements
+Convert & Transfer Arduino elements to JSON elements. This function sends a chunk of 
-Initially this function used to send the control element data individually.
+JSON describing the controls of the UI, starting from the control at index startidx.
-Due to a change in the ESPAsyncWebserver library this had top be changed to be
+If startidx is 0 then a UI_INITIAL_GUI message will be sent, else a UI_EXTEND_GUI.
-sent as one blob at the beginning. Therefore a new type is used as well
+Both message types contain a list of serialised UI elements. Only a portion of the UI
+will be sent in order to avoid websocket buffer overflows. The client will acknowledge 
+receipt of a partial message by requesting the next chunk of UI.
+
+The protocol is:
+SERVER: jsonDom(0): 
+    "UI_INITIAL_GUI: n serialised UI elements"
+CLIENT: controls.js:handleEvent()
+    "uiok:n"
+SERVER: jsonDom(n):
+    "UI_EXTEND_GUI: n serialised UI elements"
+CLIENT: controls.js:handleEvent()
+    "uiok:2*n"
+etc. 
 */
-void ESPUIClass::jsonDom(AsyncWebSocketClient* client)
+void ESPUIClass::jsonDom(uint16_t startidx, AsyncWebSocketClient* client)
 {
+    if(startidx >= this->controlCount)
+    {
+        return;
+    }
 
     DynamicJsonDocument document(jsonInitialDocumentSize);
-    document["type"] = (int)UI_INITIAL_GUI;
+    document["type"] = startidx ? (int)UI_EXTEND_GUI : (int)UI_INITIAL_GUI;
     document["sliderContinuous"] = sliderContinuous;
+    document["startindex"] = startidx;
+    document["totalcontrols"] = this->controlCount;
     JsonArray items = document.createNestedArray("controls");
-
-    Control* control = this->controls;
-
     JsonObject titleItem = items.createNestedObject();
     titleItem["type"] = (int)UI_TITLE;
     titleItem["label"] = ui_title;
 
-    while (1)
+    prepareJSONChunk(client, startidx, &items);
-    {
-        control = prepareJSONChunk(client, control, &items);
 
-        String json;
+    String json;
-        serializeJson(document, json);
+    serializeJson(document, json);
 #if defined(DEBUG_ESPUI)
-        if (this->verbosity >= Verbosity::VerboseJSON)
+    if (this->verbosity >= Verbosity::VerboseJSON)
-        {
+    {
-            Serial.println("Sending elements --------->");
+        Serial.println("Sending elements --------->");
-            Serial.println(json);
+        Serial.println(json);
-        }
-#endif
-        if (client != nullptr)
-            client->text(json);
-        else
-            this->ws->textAll(json);
-
-        if (control == nullptr)
-            break;
-
-        document.clear();
-        items.clear();
-        document["type"] = (int)UI_EXTEND_GUI;
-        items = document.createNestedArray("controls");
     }
+#endif
+    if (client != nullptr)
+        client->text(json);
+    else
+        this->ws->textAll(json);
 }
 
 /* Prepare a chunk of elements as a single JSON string. If the allowed number of elements is greater than the total
-number this will represent the entire UI and this function will return null. If a control pointer is returned then the
+number this will represent the entire UI. More likely, it will represent a small section of the UI to be sent. The client
-limit was reached, the currently serialised must be sent, and then processing resumed to send the next chunk. */
+will acknoledge receipt by requesting the next chunk. */
-Control* ESPUIClass::prepareJSONChunk(AsyncWebSocketClient* client, Control* control, JsonArray* items)
+void ESPUIClass::prepareJSONChunk(AsyncWebSocketClient* client, uint16_t startindex, JsonArray* items)
 {
-    int elementcount = 0;
+    //First check that there will be sufficient nodes in the list
+    if(startindex >= this->controlCount) 
+    {
+        return;
+    }
 
+    //Follow the list until control points to the startindex'th node
+    Control* control = this->controls;
+    for(auto i = 0; i < startindex; i++) {
+        control = control->next;
+    }
+
+    //To prevent overflow, keep track of the number of elements we have serialised into this message
+    int elementcount = 0;
     while (control != nullptr && elementcount < 10)
     {
         JsonObject item = items->createNestedObject();
@@ -1071,7 +1105,7 @@ Control* ESPUIClass::prepareJSONChunk(AsyncWebSocketClient* client, Control* con
         control = control->next;
         elementcount++;
     }
-    return control;
+    return;
 }
 
 void ESPUIClass::jsonReload()

src/ESPUI.h

@@ -298,7 +298,7 @@ public:
     const char* ui_title = "ESPUI"; // Store UI Title and Header Name
     Control* controls = nullptr;
     void jsonReload();
-    void jsonDom(AsyncWebSocketClient* client = nullptr);
+    void jsonDom(uint16_t startidx, AsyncWebSocketClient* client = nullptr);
 
     Verbosity verbosity;
 
@@ -310,7 +310,9 @@ private:
     const char* basicAuthPassword = nullptr;
     bool basicAuth = true;
 
-    Control* prepareJSONChunk(AsyncWebSocketClient* client, Control* control, JsonArray* items);
+    uint16_t controlCount = 0;
+
+    void prepareJSONChunk(AsyncWebSocketClient* client, uint16_t startindex, JsonArray* items);
 };
 
 extern ESPUIClass ESPUI;