fixed problem with undo. regularized all linkfollowing anchor fields to start with followLink<xxx>. added ease vs linear flag for scroll transitions in link and preselmeent navigations. added link follow to move target to specified offset from source. shifted from setting dropAction on items to setting childDropAction on collections

1 files changed, 19 insertions, 10 deletions

diff --git a/src/Utils.ts b/src/Utils.ts
index 5e0514bc6..9d3b9eb2b 100644
--- a/src/Utils.ts
+++ b/src/Utils.ts
@@ -558,9 +558,13 @@ export namespace JSONUtils {
     }
 }
 
-const easeInOutQuad = (currentTime: number, start: number, change: number, duration: number) => {
-    let newCurrentTime = currentTime / (duration / 2);
+const easeFunc = (transition: 'ease' | 'linear' | undefined, currentTime: number, start: number, change: number, duration: number) => {
+    if (transition === 'linear') {
+        let newCurrentTime = currentTime / duration; //  currentTime / (duration / 2);
+        return start + newCurrentTime * change;
+    }
 
+    let newCurrentTime = currentTime / (duration / 2);
     if (newCurrentTime < 1) {
         return (change / 2) * newCurrentTime * newCurrentTime + start;
     }
@@ -569,23 +573,28 @@ const easeInOutQuad = (currentTime: number, start: number, change: number, durat
     return (-change / 2) * (newCurrentTime * (newCurrentTime - 2) - 1) + start;
 };
 
-export function smoothScroll(duration: number, element: HTMLElement | HTMLElement[], to: number) {
+export function smoothScroll(duration: number, element: HTMLElement | HTMLElement[], to: number, transition: 'ease' | 'linear' | undefined, stopper?: () => void) {
+    stopper?.();
     const elements = element instanceof HTMLElement ? [element] : element;
     const starts = elements.map(element => element.scrollTop);
     const startDate = new Date().getTime();
-
+    let _stop = false;
+    const stop = () => (_stop = true);
     const animateScroll = () => {
         const currentDate = new Date().getTime();
         const currentTime = currentDate - startDate;
-        elements.map((element, i) => (element.scrollTop = easeInOutQuad(currentTime, starts[i], to - starts[i], duration)));
+        elements.map((element, i) => (element.scrollTop = easeFunc(transition, currentTime, starts[i], to - starts[i], duration)));
 
-        if (currentTime < duration) {
-            requestAnimationFrame(animateScroll);
-        } else {
-            elements.forEach(element => (element.scrollTop = to));
+        if (!_stop) {
+            if (currentTime < duration) {
+                requestAnimationFrame(animateScroll);
+            } else {
+                elements.forEach(element => (element.scrollTop = to));
+            }
         }
     };
     animateScroll();
+    return stop;
 }
 
 export function smoothScrollHorizontal(duration: number, element: HTMLElement | HTMLElement[], to: number) {
@@ -596,7 +605,7 @@ export function smoothScrollHorizontal(duration: number, element: HTMLElement |
     const animateScroll = () => {
         const currentDate = new Date().getTime();
         const currentTime = currentDate - startDate;
-        elements.map((element, i) => (element.scrollLeft = easeInOutQuad(currentTime, starts[i], to - starts[i], duration)));
+        elements.map((element, i) => (element.scrollLeft = easeFunc('ease', currentTime, starts[i], to - starts[i], duration)));
 
         if (currentTime < duration) {
             requestAnimationFrame(animateScroll);