CompositeBar: fix overflow math

src/vs/workbench/browser/parts/activitybar/activitybarPart.ts

@@ -75,7 +75,8 @@ export class ActivitybarPart extends Part {
 			getOnCompositeClickAction: (compositeId: string) => this.instantiationService.createInstance(ToggleViewletAction, this.viewletService.getViewlet(compositeId)),
 			getDefaultCompositeId: () => this.viewletService.getDefaultViewletId(),
 			hidePart: () => this.partService.setSideBarHidden(true),
-			colors: ActivitybarPart.COLORS
+			colors: ActivitybarPart.COLORS,
+			overflowActionSize: 50
 		});
 		this.registerListeners();
 	}

src/vs/workbench/browser/parts/compositebar/compositeBar.ts

@@ -26,6 +26,7 @@ export interface ICompositeBarOptions {
 	orientation: ActionsOrientation;
 	composites: { id: string, name: string }[];
 	colors: ICompositeBarColors;
+	overflowActionSize: number;
 	getActivityAction: (compositeId: string) => ActivityAction;
 	getCompositePinnedAction: (compositeId: string) => Action;
 	getOnCompositeClickAction: (compositeId: string) => Action;
@@ -36,7 +37,6 @@ export interface ICompositeBarOptions {
 
 export class CompositeBar implements ICompositeBar {
 
-	private static OVERFLOW_ACTION_SIZE = 50;
 	private _onDidContextMenu: Emitter<MouseEvent>;
 
 	private dimension: Dimension;
@@ -220,9 +220,12 @@ export class CompositeBar implements ICompositeBar {
 			}
 			overflows = compositesToShow.length > maxVisible;
 
-			compositesToShow = compositesToShow.slice(0, maxVisible);
-			// Check if we need to make room for the overflow action
-			if (overflows && (size + CompositeBar.OVERFLOW_ACTION_SIZE - this.compositeSizeInBar.get(compositesToShow[maxVisible - 1]) - this.compositeSizeInBar.get(compositesToShow[maxVisible]) > limit)) {
+			if (overflows) {
+				size -= this.compositeSizeInBar.get(compositesToShow[maxVisible]);
+				compositesToShow = compositesToShow.slice(0, maxVisible);
+			}
+			// Check if we need to make extra room for the overflow action
+			if (overflows && (size + this.options.overflowActionSize > limit)) {
 				compositesToShow.pop();
 			}
 		}

src/vs/workbench/browser/parts/panel/panelPart.ts

@@ -84,6 +84,7 @@ export class PanelPart extends CompositePart<Panel> implements IPanelService {
 			getOnCompositeClickAction: (compositeId: string) => this.instantiationService.createInstance(OpenPanelAction, this.getPanel(compositeId)),
 			getDefaultCompositeId: () => Registry.as<PanelRegistry>(PanelExtensions.Panels).getDefaultPanelId(),
 			hidePart: () => this.partService.setPanelHidden(true),
+			overflowActionSize: 60,
 			colors: {
 				backgroundColor: PANEL_BACKGROUND,
 				badgeBackground,
@@ -207,7 +208,7 @@ export class PanelPart extends CompositePart<Panel> implements IPanelService {
 
 		// Pass to super
 		const sizes = super.layout(dimension);
-		let availableWidth = dimension.width;
+		let availableWidth = dimension.width - 8; // take padding into account
 		if (this.toolBar) {
 			// adjust height for global actions showing
 			availableWidth -= this.toolBar.getContainer().getHTMLElement().offsetWidth;