Fix flickering and arrows position

Signed-off-by: DmitriyNoa <dmytro.zharkov@gmail.com>

src/renderer/components/dock/__test__/dock-tabs.test.tsx

@@ -49,6 +49,7 @@ const getComponent = (dockStore: DockStore) => (
     selectedTab={dockStore.selectedTab}
     autoFocus={true}
     onChangeTab={noop}
+    dockStore={dockStore}
   />
 );
 

src/renderer/components/dock/dock-store/dock.store.ts

@@ -97,6 +97,11 @@ export interface DockTabCloseEvent {
   tabId: TabId; // closed tab id
 }
 
+export interface DockTabsNumberEvent {
+  currentTabsNumber: number; // number of open tabs
+  previousTabsNumber: number;
+}
+
 interface Dependencies {
   storage: StorageHelper<DockStorageState>
 }
@@ -160,6 +165,10 @@ export class DockStore implements DockStorageState {
     this.dependencies.storage.merge({ selectedTabId: tabId });
   }
 
+  @computed get tabsNumber() : number {
+    return this.tabs.length;
+  }
+
   @computed get selectedTab() {
     return this.tabs.find(tab => tab.id === this.selectedTabId);
   }
@@ -224,6 +233,15 @@ export class DockStore implements DockStorageState {
     }), reactionOpts);
   }
 
+  onTabsNumberChange(callback: (evt: DockTabsNumberEvent) => void) {
+    return reaction(() => this.tabsNumber, ((currentTabsNumber, previousTabsNumber) => {
+      callback({
+        currentTabsNumber,
+        previousTabsNumber,
+      });
+    }));
+  }
+
   hasTabs() {
     return this.tabs.length > 0;
   }

src/renderer/components/dock/dock-tabs.tsx

@@ -8,17 +8,18 @@ import { Icon } from "../icon";
 import { Tabs } from "../tabs/tabs";
 import { DockTab } from "./dock-tab";
 import type { DockTab as DockTabModel } from "./dock-store/dock.store";
-import { TabKind } from "./dock-store/dock.store";
+import { TabKind, DockStore } from "./dock-store/dock.store";
 import { TerminalTab } from "./terminal-tab";
 
 interface Props {
   tabs: DockTabModel[]
+  dockStore: DockStore;
   autoFocus: boolean
   selectedTab: DockTabModel
   onChangeTab: (tab: DockTabModel) => void
 }
 
-export const DockTabs = ({ tabs, autoFocus, selectedTab, onChangeTab }: Props) => {
+export const DockTabs = ({ tabs, autoFocus, selectedTab, onChangeTab, dockStore }: Props) => {
   const elem = useRef(null);
   const contentElem = useRef(null);
   const [contentWidth, setContentWidth] = useState(0);
@@ -27,7 +28,7 @@ export const DockTabs = ({ tabs, autoFocus, selectedTab, onChangeTab }: Props) =
   const scrollStep = 200;
 
   const scrollToRight = (): void => {
-    if(!elem || scrollPosition + scrollStep > contentWidth) return;
+    if(!elem || scrollPosition === contentWidth) return;
     const scroll = scrollPosition + scrollStep;
 
     setScrollPosition(scroll);
@@ -35,6 +36,14 @@ export const DockTabs = ({ tabs, autoFocus, selectedTab, onChangeTab }: Props) =
     elem.current.scrollLeft = scroll;
   };
 
+  const updateStateValues = () => {
+    if(!elem || !contentElem) return;
+
+    setContentWidth(contentElem.current.clientWidth);
+    setContainerWidth(elem.current.clientWidth);
+    setScrollPosition(elem.current.scrollLeft);
+  };
+
   const scrollToLeft = (): void => {
     if(!elem) return;
     const scroll = scrollPosition - scrollStep;
@@ -47,13 +56,15 @@ export const DockTabs = ({ tabs, autoFocus, selectedTab, onChangeTab }: Props) =
   const  isScrollableRight = (): boolean => {
     if(!elem || !contentElem) return false;
 
-    return contentWidth > containerWidth && scrollPosition < contentWidth - containerWidth;
+    // check if element with tabs is wider than the parent element
+    // check if scroll at the end of scrollable area.
+    return contentElem.current?.clientWidth  > containerWidth && scrollPosition  < contentElem.current?.clientWidth - elem.current?.clientWidth;
   };
 
   const  isScrollableLeft = (): boolean => {
     if(!elem || !contentElem) return false;
 
-    return scrollPosition > scrollStep;
+    return scrollPosition > 0;
   };
 
   const updateScrollPosition = ( evt: UIEvent<HTMLDivElement>): void => {
@@ -65,11 +76,7 @@ export const DockTabs = ({ tabs, autoFocus, selectedTab, onChangeTab }: Props) =
   };
 
   const onWindowResize = (): void => {
-    if(!elem || !contentElem) return;
-
-    setContentWidth(contentElem.current.clientWidth);
-    setContainerWidth(elem.current.clientWidth);
-    setScrollPosition(elem.current.scrollLeft);
+    updateStateValues();
   };
 
   const renderTab = (tab?: DockTabModel) => {
@@ -93,17 +100,18 @@ export const DockTabs = ({ tabs, autoFocus, selectedTab, onChangeTab }: Props) =
 
 
   useEffect(() => {
-    if(!elem || !contentElem) return;
-
-    setContentWidth(contentElem.current.clientWidth);
-    setContainerWidth(elem.current.clientWidth);
-    setScrollPosition(elem.current.scrollLeft);
+    updateStateValues();
 
     // update values in store on scroll
     elem.current.addEventListener("scroll", updateScrollPosition);
 
     // update current values on resize to show/hide scroll
     window.addEventListener("resize", onWindowResize);
+
+    // update scroll state if tabs numbers has changed
+    dockStore.onTabsNumberChange(() => {
+      updateStateValues();
+    });
   }, []);
 
   return (

src/renderer/components/dock/dock.scss

@@ -60,6 +60,10 @@
 
   .tabs-wrapper {
     overflow: hidden;
+    width: 100%;
+    box-sizing: border-box;
+    position: relative;
+    padding: 0 $padding*2.5;
   }
 
   .tab-content {
@@ -83,7 +87,7 @@
 
   .tabs-control {
     overflow: auto;
-    position: relative;
+    width: 100%;
 
     &::-webkit-scrollbar {
       visibility: hidden;
@@ -100,20 +104,6 @@
     &:hover::-webkit-scrollbar-thumb {
       background: var(--scrollBarColor);
     }
-
-    .tab-control {
-      position: absolute;
-      z-index: 9999;
-    }
-
-    .scroll-left {
-      left: 0;
-    }
-
-    .right {
-      right: 0;
-    }
-
   }
 
   .DockTab.active {
@@ -123,4 +113,18 @@
       color: var(--terminalWhite);
     }
   }
+
+  .tab-control {
+    position: absolute;
+    z-index: 9999;
+  }
+
+  .scroll-left {
+    left: 0;
+  }
+
+  .scroll-right {
+    right: 0;
+  }
+
 }

src/renderer/components/dock/dock.tsx

@@ -157,6 +157,7 @@ class NonInjectedDock extends React.Component<Props & Dependencies> {
             selectedTab={selectedTab}
             autoFocus={isOpen}
             onChangeTab={this.onChangeTab}
+            dockStore={dockStore}
           />
           <div className="toolbar flex gaps align-center box grow">
             <div className="dock-menu box grow">