bug fixed

projects/ucap-webmessenger-ui-chat/src/lib/components/messages.component.ts

@@ -425,39 +425,29 @@ export class MessagesComponent implements OnInit, OnDestroy {
     useSwap: boolean,
     addtionalOffset?: number
   ) {
-    if (!!to) {
+    this.preSwapScroll(useHide, useSwap);
-      this.preSwapScroll(useHide, useSwap);
+    if (!!preCallback) {
-      if (!!preCallback) {
+      preCallback();
-        preCallback();
-      }
-
-      this.virtualScroller.scrollInto(
-        to,
-        true,
-        undefined !== this.storedScrollItemOffsetTop
-          ? -this.storedScrollItemOffsetTop
-          : undefined !== addtionalOffset
-          ? -addtionalOffset
-          : 0,
-        0,
-        () => {
-          setTimeout(() => {
-            if (!!postCallback) {
-              postCallback();
-            }
-            this.postSwapScroll(useHide, useSwap);
-          });
-        }
-      );
-    } else {
-      if (!!preCallback) {
-        preCallback();
-      }
-
-      if (!!postCallback) {
-        postCallback();
-      }
     }
+
+    this.virtualScroller.scrollInto(
+      to,
+      true,
+      undefined !== this.storedScrollItemOffsetTop
+        ? -this.storedScrollItemOffsetTop
+        : undefined !== addtionalOffset
+        ? -addtionalOffset
+        : 0,
+      0,
+      () => {
+        setTimeout(() => {
+          if (!!postCallback) {
+            postCallback();
+          }
+          this.postSwapScroll(useHide, useSwap);
+        });
+      }
+    );
   }
 
   preSwapScroll(useHide: boolean, useSwap: boolean) {
@@ -540,6 +530,12 @@ export class MessagesComponent implements OnInit, OnDestroy {
           return;
         }
 
+        if (!!this.gotoEventSeq) {
+          this.gotoPosition(this.gotoEventSeq);
+          this.gotoEventSeq = undefined;
+          return;
+        }
+
         const lastEvent =
           !!this.eventList && 0 < this.eventList.length
             ? this.eventList[this.eventList.length - 1]
@@ -550,20 +546,14 @@ export class MessagesComponent implements OnInit, OnDestroy {
         }
         const isInViewPortItems = this.isInViewPortItems(lastEvent.seq);
         this.swapScrollTo(
-          !!this.gotoEventSeq
+          this.eventList[this.eventList.length - 1],
-            ? undefined
-            : this.eventList[this.eventList.length - 1],
           () => {},
           () => {
             this.initalized = true;
-            if (!!this.gotoEventSeq) {
-              this.gotoPosition(this.gotoEventSeq);
-              this.gotoEventSeq = undefined;
-            }
           },
           -1 === this.virtualScroller.viewPortInfo.endIndex ||
             !isInViewPortItems,
-          !isInViewPortItems || !!this.gotoEventSeq
+          !isInViewPortItems
         );
       }
     }