Create RFB object on connect

In e543525f, we switched to creating
a new RFB object on disconnect.  This caused issues, however, since
any errors were only displayed briefly before the new "loaded" text
was displayed instead.

Now, we create the RFB object on connect.  This essentially removes
the usefulness of the "loaded" state, but prevents the aforementioned
problem.

To facilitate this, the code which does detection of cursor URI support
was moved from this Display constructor (which now calls the new
function) into its own function, `Util.browserSupportsCursorURIs()`.

Fixes #467

include/display.js

@@ -86,29 +86,9 @@ var Display;
         }
 
         // Determine browser support for setting the cursor via data URI scheme
-        var curDat = [];
-        for (var i = 0; i < 8 * 8 * 4; i++) {
-            curDat.push(255);
-        }
-        try {
-            var curSave = this._target.style.cursor;
-            Display.changeCursor(this._target, curDat, curDat, 2, 2, 8, 8);
-            if (this._target.style.cursor) {
-                if (this._cursor_uri === null || this._cursor_uri === undefined) {
-                    this._cursor_uri = true;
-                }
-                Util.Info("Data URI scheme cursor supported");
-                this._target.style.cursor = curSave;
-            } else {
-                if (this._cursor_uri === null || this._cursor_uri === undefined) {
-                    this._cursor_uri = false;
-                }
-                Util.Warn("Data URI scheme cursor not supported");
-                this._target.style.cursor = "none";
-            }
-        } catch (exc) {
-            Util.Error("Data URI scheme cursor test exception: " + exc);
-            this._cursor_uri = false;
+        if (this._cursor_uri || this._cursor_uri === null ||
+                this._cursor_uri === undefined) {
+            this._cursor_uri = Util.browserSupportsCursorURIs(this._target);
         }
 
         Util.Debug("<< Display.constructor");

include/ui.js

@@ -97,8 +97,6 @@ var UI;
             UI.initSetting('path', 'websockify');
             UI.initSetting('repeaterID', '');
 
-            UI.initRFB();
-
             var autoconnect = WebUtil.getQueryVar('autoconnect', false);
             if (autoconnect === 'true' || autoconnect == '1') {
                 autoconnect = true;
@@ -136,7 +134,7 @@ var UI;
             Util.addEvent(window, 'load', UI.keyboardinputReset);
 
             Util.addEvent(window, 'beforeunload', function () {
-                if (UI.rfb_state === 'normal') {
+                if (UI.rfb && UI.rfb_state === 'normal') {
                     return "You are currently connected.";
                 }
             } );
@@ -213,12 +211,14 @@ var UI;
             $D("noVNC_connect_button").onclick = UI.connect;
 
             $D("noVNC_resize").onchange = function () {
-                var connected = UI.rfb_state === 'normal' ? true : false;
+                var connected = UI.rfb && UI.rfb_state === 'normal';
                 UI.enableDisableClip(connected);
             };
         },
 
         onresize: function (callback) {
+            if (!UI.rfb) return;
+
             var size = UI.getCanvasLimit();
 
             if (size && UI.rfb_state === 'normal' && UI.rfb.get_display()) {
@@ -480,7 +480,7 @@ var UI;
             } else {
                 UI.updateSetting('encrypt');
                 UI.updateSetting('true_color');
-                if (UI.rfb.get_display().get_cursor_uri()) {
+                if (Util.browserSupportsCursorURIs()) {
                     UI.updateSetting('cursor');
                 } else {
                     UI.updateSetting('cursor', !UI.isTouchDevice);
@@ -536,7 +536,7 @@ var UI;
             //Util.Debug(">> settingsApply");
             UI.saveSetting('encrypt');
             UI.saveSetting('true_color');
-            if (UI.rfb.get_display().get_cursor_uri()) {
+            if (Util.browserSupportsCursorURIs()) {
                 UI.saveSetting('cursor');
             }
 
@@ -558,7 +558,7 @@ var UI;
             WebUtil.selectStylesheet(UI.getSetting('stylesheet'));
             WebUtil.init_logging(UI.getSetting('logging'));
             UI.setViewClip();
-            UI.setViewDrag(UI.rfb.get_viewportDrag());
+            UI.setViewDrag(UI.rfb && UI.rfb.get_viewportDrag());
             //Util.Debug("<< settingsApply");
         },
 
@@ -642,13 +642,6 @@ var UI;
                     break;
             }
 
-            switch (state) {
-                case 'fatal':
-                case 'failed':
-                case 'disconnected':
-                    UI.initRFB();
-            }
-
             if (typeof(msg) !== 'undefined') {
                 $D('noVNC-control-bar').setAttribute("class", klass);
                 $D('noVNC_status').innerHTML = msg;
@@ -659,13 +652,12 @@ var UI;
 
         // Disable/enable controls depending on connection state
         updateVisualState: function() {
-            var connected = UI.rfb_state === 'normal' ? true : false;
+            var connected = UI.rfb && UI.rfb_state === 'normal';
 
             //Util.Debug(">> updateVisualState");
             $D('noVNC_encrypt').disabled = connected;
             $D('noVNC_true_color').disabled = connected;
-            if (UI.rfb && UI.rfb.get_display() &&
-                UI.rfb.get_display().get_cursor_uri()) {
+            if (Util.browserSupportsCursorURIs()) {
                 $D('noVNC_cursor').disabled = connected;
             } else {
                 UI.updateSetting('cursor', !UI.isTouchDevice);
@@ -780,6 +772,8 @@ var UI;
                 throw new Error("Must set host and port");
             }
 
+            UI.initRFB();
+
             UI.rfb.set_encrypt(UI.getSetting('encrypt'));
             UI.rfb.set_true_color(UI.getSetting('true_color'));
             UI.rfb.set_local_cursor(UI.getSetting('cursor'));
@@ -809,11 +803,15 @@ var UI;
         },
 
         displayBlur: function() {
+            if (!UI.rfb) return;
+
             UI.rfb.get_keyboard().set_focused(false);
             UI.rfb.get_mouse().set_focused(false);
         },
 
         displayFocus: function() {
+            if (!UI.rfb) return;
+
             UI.rfb.get_keyboard().set_focused(true);
             UI.rfb.get_mouse().set_focused(true);
         },
@@ -882,7 +880,7 @@ var UI;
 
         // Toggle/set/unset the viewport drag/move button
         setViewDrag: function(drag) {
-            if (!UI.rfb) { return; }
+            if (!UI.rfb) return;
 
             UI.updateViewDragButton();
 
@@ -953,7 +951,7 @@ var UI;
         // sending keyCodes in the normal keyboard events when using on screen keyboards.
         keyInput: function(event) {
 
-            if (!UI.rfb) { return; }
+            if (!UI.rfb) return;
 
             var newValue = event.target.value;
 

include/util.js

@@ -508,6 +508,29 @@ Util.stopEvent = function (e) {
     else                   { e.returnValue = false; }
 };
 
+Util._cursor_uris_supported = null;
+
+Util.browserSupportsCursorURIs = function () {
+    if (Util._cursor_uris_supported === null) {
+        try {
+            var target = document.createElement('canvas');
+            target.style.cursor = 'url("data:image/x-icon;base64,AAACAAEACAgAAAIAAgA4AQAAFgAAACgAAAAIAAAAEAAAAAEAIAAAAAAAEAAAAAAAAAAAAAAAAAAAAAAAAAD/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////AAAAAAAAAAAAAAAAAAAAAA==") 2 2, default';
+
+            if (target.style.cursor) {
+                Util.Info("Data URI scheme cursor supported");
+                Util._cursor_uris_supported = true;
+            } else {
+                Util.Warn("Data URI scheme cursor not supported");
+                Util._cursor_uris_supported = false;
+            }
+        } catch (exc) {
+            Util.Error("Data URI scheme cursor test exception: " + exc);
+            Util._cursor_uris_supported = false;
+        }
+    }
+
+    return Util._cursor_uris_supported;
+};
 
 // Set browser engine versions. Based on mootools.
 Util.Features = {xpath: !!(document.evaluate), air: !!(window.runtime), query: !!(document.querySelector)};

tests/test.display.js

@@ -28,35 +28,29 @@ describe('Display/Canvas Helper', function () {
 
     describe('checking for cursor uri support', function () {
         beforeEach(function () {
-            this._old_change_cursor = Display.changeCursor;
+            this._old_browser_supports_cursor_uris = Util.browserSupportsCursorURIs;
         });
 
         it('should disable cursor URIs if there is no support', function () {
-            Display.changeCursor = function(target) {
-                target.style.cursor = undefined;
-            };
+            Util.browserSupportsCursorURIs = function () { return false; };
             var display = new Display({ target: document.createElement('canvas'), prefer_js: true, viewport: false });
             expect(display._cursor_uri).to.be.false;
         });
 
         it('should enable cursor URIs if there is support', function () {
-            Display.changeCursor = function(target) {
-                target.style.cursor = 'pointer';
-            };
+            Util.browserSupportsCursorURIs = function () { return true; };
             var display = new Display({ target: document.createElement('canvas'), prefer_js: true, viewport: false });
             expect(display._cursor_uri).to.be.true;
         });
 
         it('respect the cursor_uri option if there is support', function () {
-            Display.changeCursor = function(target) {
-                target.style.cursor = 'pointer';
-            };
+            Util.browserSupportsCursorURIs = function () { return false; };
             var display = new Display({ target: document.createElement('canvas'), prefer_js: true, viewport: false, cursor_uri: false });
             expect(display._cursor_uri).to.be.false;
         });
 
         afterEach(function () {
-            Display.changeCursor = this._old_change_cursor;
+            Util.browserSupportsCursorURIs = this._old_browser_supports_cursor_uris;
         });
     });
 

vnc.html

@@ -46,7 +46,7 @@
 </head>
 
 <body>
-    <div id="noVNC-control-bar">
+    <div id="noVNC-control-bar" class="noVNC_status_normal">
         <!--noVNC Mobile Device only Buttons-->
         <div class="noVNC-buttons-left">
             <input type="image" alt="viewport drag" src="images/drag.png"
@@ -87,7 +87,7 @@
             </div>
         </div>
 
-        <div id="noVNC_status">Loading</div>
+        <div id="noVNC_status"></div>
 
         <!--noVNC Buttons-->
         <div class="noVNC-buttons-right">