messagegui: compatibility with kineticscroll

Author: thyttan

apps/messagegui/app.js

@@ -369,13 +369,15 @@ function showMessagesScroller(msg, persist, alreadyProcessed) {
         alreadyProcessed.idxSpan.stop<MESSAGES.length) {
         setTimeout(() => {
           E.showScroller();
+          if (BTN_WATCH) {clearWatch(BTN_WATCH);}
           showMessagesScroller(MESSAGES[alreadyProcessed.idxSpan.stop],
             true, alreadyProcessed);
         }, 40);
       }
       if (scrollIdx==0 && scrollIdx!=prevScrollIdx && alreadyProcessed.idxSpan.start>0) {
         setTimeout(() => {
           E.showScroller();
+          if (BTN_WATCH) {clearWatch(BTN_WATCH);}
           showMessagesScroller(MESSAGES[alreadyProcessed.idxSpan.start-1],
             true, alreadyProcessed);
         }, 40);
@@ -397,11 +399,15 @@ function showMessagesScroller(msg, persist, alreadyProcessed) {
       }
     }
   });
+
   const BTN_WATCH = setWatch(()=>{
-    WU.show();
-    const SCROLL_IDX_CENTER_SCREEN = prevScrollIdx>prevPrevScrollIdx ?
+    Bangle.emit("drag", {dy:0}); // Compatibility with `kineticscroll`, stopping the scroller so it doesn't continue scrolling when the `showMessage` screen is loaded.
+    // Zero ms timeout as to not move on before the scroller has registered the emitted drag event.
+    setTimeout(()=>{const SCROLL_IDX_CENTER_SCREEN = prevScrollIdx>prevPrevScrollIdx ?
       prevScrollIdx-5 : prevScrollIdx+5; // FIXME: `±5` should depend on screen height and font height.
-    showMessage(identifyDisplayedMsg(SCROLL_IDX_CENTER_SCREEN).id, true);
+      WU.show();
+      showMessage(identifyDisplayedMsg(SCROLL_IDX_CENTER_SCREEN).id, true);
+    },0)
   }, BTN, {edge:'rising'});
 }