angular-ui · dhilt · May 22, 2018 · May 24, 2018 · May 24, 2018 · May 24, 2018
diff --git a/bower.json b/bower.json
@@ -1,7 +1,7 @@
 {
   "name": "angular-ui-scroll",
   "description": "AngularJS infinite scrolling module",
-  "version": "1.7.2",
+  "version": "1.8.0-rc",
   "main": "./dist/ui-scroll.js",
   "homepage": "https://github.com/angular-ui/ui-scroll.git",
   "license": "MIT",

diff --git a/demo/serviceDatasource/serviceDatasource.html b/demo/serviceDatasource/serviceDatasource.html
@@ -39,10 +39,14 @@ <h1 class="page-header page-header-exapmle">Datasource as service</h1>
 		</div>
 
 		<div class="viewport" id="viewport-serviceDatasource" ui-scroll-viewport>
-			<div class="item" ui-scroll="item in datasource">{{item}}</div>
+			<div class="item" ui-scroll="item in datasource">
+				<div ng-if="$index%10 === 0 && $index%20 !== 0">{{item}} ************ {{$index}}</div>
+				<div ng-if="$index%10 === 0 && $index%20 === 0">{{item}} ************ {{$index}} OOOOOOOOOOOO </div>
+				<div ng-if="$index%10 !== 0">{{item}}</div>
+			</div>
 		</div>
 
 	</div>
 
 </body>
-</html>
+</html>
diff --git a/demo/serviceDatasource/serviceDatasource.js b/demo/serviceDatasource/serviceDatasource.js
@@ -9,7 +9,7 @@ angular.module('application', ['ui.scroll'])
 						result.push("item #" + i);
 					}
 					success(result);
-				}, 100);
+				}, 700);
 			};
 
 			return {

diff --git a/dist/ui-scroll-grid.js b/dist/ui-scroll-grid.js
diff --git a/dist/ui-scroll-grid.js.map b/dist/ui-scroll-grid.js.map
diff --git a/dist/ui-scroll-grid.min.js b/dist/ui-scroll-grid.min.js
diff --git a/dist/ui-scroll-grid.min.js.map b/dist/ui-scroll-grid.min.js.map
diff --git a/dist/ui-scroll.js b/dist/ui-scroll.js
diff --git a/dist/ui-scroll.js.map b/dist/ui-scroll.js.map
diff --git a/dist/ui-scroll.min.js b/dist/ui-scroll.min.js
diff --git a/dist/ui-scroll.min.js.map b/dist/ui-scroll.min.js.map
diff --git a/package.json b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "angular-ui-scroll",
   "description": "AngularJS infinite scrolling module",
-  "version": "1.7.2",
+  "version": "1.8.0-rc",
   "src": "./src/",
   "public": "./dist/",
   "main": "./dist/ui-scroll.js",

diff --git a/src/modules/adapter.js b/src/modules/adapter.js
@@ -43,7 +43,7 @@ class Adapter {
 
   generatePublicContext() {
     // these methods will be accessible out of ui-scroll via user defined adapter
-    const publicMethods = ['reload', 'applyUpdates', 'append', 'prepend', 'isBOF', 'isEOF', 'isEmpty'];
+    const publicMethods = ['reload', 'applyUpdates', 'append', 'prepend', 'isBOF', 'isEOF', 'isEmpty', 'resetScrollTopCorrection'];
     for (let i = publicMethods.length - 1; i >= 0; i--) {
       this.publicContext[publicMethods[i]] = this[publicMethods[i]].bind(this);
     }
@@ -87,6 +87,11 @@ class Adapter {
     return !this.buffer.length;
   }
 
+  resetScrollTopCorrection() {
+    // is needed to scroll at negative area programmatically (e.g. tests)
+    this.viewport.scrollTopValue = null;
+  }
+
   append(newItems) {
     this.buffer.append(newItems);
     this.doAdjust();

diff --git a/src/modules/viewport.js b/src/modules/viewport.js
@@ -13,6 +13,10 @@ export default function Viewport(elementRoutines, buffer, element, viewportContr
     'display': 'block'
   });
 
+  viewport.scrollTopOriginal = viewport.scrollTopOriginal || viewport.scrollTop;
+  viewport.scrollTopBeforeSet = null;
+  viewport.scrollTopValue = null;
+
   function bufferPadding() {
     return viewport.outerHeight() * padding; // some extra space to initiate preload
   }
@@ -22,6 +26,14 @@ export default function Viewport(elementRoutines, buffer, element, viewportContr
       return scope;
     },
 
+    scrollTop() {
+      if (typeof arguments[0] !== 'undefined') {
+        viewport.scrollTopBeforeSet = viewport.scrollTop();
+        viewport.scrollTopValue = arguments[0];
+      }
+      return viewport.scrollTopOriginal.apply(viewport, arguments);
+    },
+
     createPaddingElements(template) {
       topPadding = new Padding(template);
       bottomPadding = new Padding(template);
@@ -97,7 +109,7 @@ export default function Viewport(elementRoutines, buffer, element, viewportContr
     },
 
     shouldLoadTop() {
-      return !buffer.bof && (viewport.topDataPos() > viewport.topVisiblePos() - bufferPadding());
+      return !buffer.bof && !viewport.scrollTopSetFailed && viewport.topDataPos() > viewport.topVisiblePos() - bufferPadding();
     },
 
     clipTop() {
@@ -187,6 +199,7 @@ export default function Viewport(elementRoutines, buffer, element, viewportContr
       }
       else {
         topPadding.height(0);
+        viewport.scrollTopAdjust = paddingHeight;
         viewport.scrollTop(viewport.scrollTop() - paddingHeight);
       }
     },

diff --git a/src/ui-scroll.js b/src/ui-scroll.js
@@ -67,7 +67,7 @@ angular.module('ui.scroll', [])
 
         const BUFFER_MIN = 3;
         const BUFFER_DEFAULT = 10;
-        const PADDING_MIN = 0.3;
+        const PADDING_MIN = 0.01;
         const PADDING_DEFAULT = 0.5;
         const MAX_VIEWPORT_DELAY = 500;
         const VIEWPORT_POLLING_INTERVAL = 50;
@@ -475,18 +475,40 @@ angular.module('ui.scroll', [])
           }
         }
 
-        function resizeAndScrollHandler() {
-          if (!$rootScope.$$phase && !adapter.isLoading && !adapter.disabled) {
+        function resizeAndScrollHandler(ev) {
+          if ($rootScope.$$phase || adapter.isLoading || adapter.disabled) {
+            return;
+          }
 
-            enqueueFetch(ridActual);
+          if (ev.type === 'scroll') {
+            // Don't process scroll event if it was triggered by us setting scrollTop.
+            if (viewport[0].scrollTop === viewport.scrollTopValue) {
+              return false;
+            }
 
-            if (pending.length) {
-              unbindEvents();
-            } else {
-              adapter.calculateProperties();
-              !$scope.$$phase && $scope.$digest();
+            // Check if we tried to set scrollTop and it failed. If that happens, don't prepend more items based on the stale value
+            // of scrollTop that will be used by shouldLoadTop(). Also, try to set it again.
+            viewport.scrollTopSetFailed = false;
+            if (viewport.scrollTopValue != null) {
+              const curScrollTop = viewport[0].scrollTop;
+              if (Math.abs(curScrollTop - viewport.scrollTopValue) > Math.abs(curScrollTop - viewport.scrollTopBeforeSet)) {
+                viewport.scrollTopSetFailed = true;
+                viewport.scrollTop(curScrollTop - viewport.scrollTopAdjust);
+              }
             }
           }
+
+          enqueueFetch(ridActual);
+
+          // we got a real scroll event, so browser is now in charge of scrollTop
+          viewport.scrollTopValue = null;
+
+          if (pending.length) {
+            unbindEvents();
+          } else {
+            adapter.calculateProperties();
+            !$scope.$$phase && $scope.$digest();
+          }
         }
 
         function wheelHandler(event) {