Sash double clicks (#4702)

* Support double click on sashes

We had to implement a slight change in the sash drag "hack", by removing the
full cover transparent overlay (that was preventing clicks events from being
fired) and replacing it by a CSS `cursor` rule on the document.body.

The ideal solution for a clean dragging events implementation would be to use
the `Element.setCapture` API that is unfortunately not available in Chrome.

* Center the split editor frontier by double-clicking on it

* Reset the bottom panel size by double-clicking on it

* Implement sash reset on diff editors

* Fix a bug with DOM measurement

The calculus was plain wrong as showed in winjs/winjs#1621
This was probably unotified since this utility function wasn't used in the code base.

* Implement sidebar sash optimal resizing

Fixes #4660

* Abstract `getLargestChildWidth` into a DOM method

This commit also moves the `getOptimalWidth` method from the `Composite` to the
`Viewlet` component. This partially addresses
#4702 (comment)

* Calculate the sidebar optimal width correctly in case no folder is open

src/vs/base/browser/dom.ts

@@ -637,46 +637,34 @@ export function getTotalHeight(element: HTMLElement): number {
 	return element.offsetHeight + margin;
 }
 
-// Adapted from WinJS
 // Gets the left coordinate of the specified element relative to the specified parent.
 export function getRelativeLeft(element: HTMLElement, parent: HTMLElement): number {
 	if (element === null) {
 		return 0;
 	}
 
-	let left = element.offsetLeft;
-	let e = <HTMLElement>element.parentNode;
-	while (e !== null) {
-		left -= e.offsetLeft;
-
-		if (e === parent) {
-			break;
-		}
-		e = <HTMLElement>e.parentNode;
-	}
-
-	return left;
+	let elementPosition = getTopLeftOffset(element);
+	let parentPosition = getTopLeftOffset(parent);
+	return elementPosition.left - parentPosition.left;
 }
 
-// Adapted from WinJS
 // Gets the top coordinate of the element relative to the specified parent.
 export function getRelativeTop(element: HTMLElement, parent: HTMLElement): number {
 	if (element === null) {
 		return 0;
 	}
 
-	let top = element.offsetTop;
-	let e = <HTMLElement>element.parentNode;
-	while (e !== null) {
-		top -= e.offsetTop;
-
-		if (e === parent) {
-			break;
-		}
-		e = <HTMLElement>e.parentNode;
-	}
+	let elementPosition = getTopLeftOffset(element);
+	let parentPosition = getTopLeftOffset(parent);
+	return parentPosition.top - elementPosition.top;
+}
 
-	return top;
+export function getLargestChildWidth(parent: HTMLElement, children: HTMLElement[]): number {
+	let childWidths = children.map((child) => {
+		return getTotalWidth(child) + getRelativeLeft(child, parent) || 0;
+	});
+	let maxWidth = Math.max(...childWidths);
+	return maxWidth;
 }
 
 // ----------------------------------------------------------------------------------------

src/vs/base/browser/ui/sash/sash.css

@@ -23,4 +23,12 @@
 
 .monaco-sash.disabled {
 	cursor: default;
+}
+
+.vertical-cursor-container * {
+	cursor: ew-resize !important;
+}
+
+.horizontal-cursor-container * {
+	cursor: ns-resize !important;
 }

src/vs/base/browser/ui/sash/sash.ts

@@ -63,11 +63,12 @@ export class Sash extends EventEmitter {
 
 		this.gesture = new Gesture(this.$e.getHTMLElement());
 
-		this.$e.on('mousedown', (e: MouseEvent) => { this.onMouseDown(e); });
+		this.$e.on(DOM.EventType.MOUSE_DOWN, (e: MouseEvent) => { this.onMouseDown(e); });
+		this.$e.on(DOM.EventType.DBLCLICK, (e: MouseEvent) => { this.emit('reset', e); });
 		this.$e.on(EventType.Start, (e: GestureEvent) => { this.onTouchStart(e); });
 
 		this.orientation = options.orientation || Orientation.VERTICAL;
-		this.$e.addClass(this.orientation === Orientation.HORIZONTAL ? 'horizontal' : 'vertical');
+		this.$e.addClass(this.getOrientation());
 
 		this.size = options.baseSize || 5;
 
@@ -91,6 +92,10 @@ export class Sash extends EventEmitter {
 		return this.$e.getHTMLElement();
 	}
 
+	private getOrientation(): 'horizontal' | 'vertical' {
+		return this.orientation === Orientation.HORIZONTAL ? 'horizontal' : 'vertical';
+	}
+
 	private onMouseDown(e: MouseEvent): void {
 		DOM.EventHelper.stop(e, false);
 
@@ -112,17 +117,8 @@ export class Sash extends EventEmitter {
 		this.$e.addClass('active');
 		this.emit('start', startEvent);
 
-		let overlayDiv = $('div').style({
-			position: 'absolute',
-			top: 0,
-			left: 0,
-			width: '100%',
-			height: '100%',
-			zIndex: 1000000,
-			cursor: this.orientation === Orientation.VERTICAL ? 'ew-resize' : 'ns-resize'
-		});
-
 		let $window = $(window);
+		let containerCssClass = `${this.getOrientation()}-cursor-container`;
 
 		let lastCurrentX = startX;
 		let lastCurrentY = startY;
@@ -148,10 +144,10 @@ export class Sash extends EventEmitter {
 			this.emit('end');
 
 			$window.off('mousemove');
-			overlayDiv.destroy();
+			document.body.classList.remove(containerCssClass);
 		});
 
-		overlayDiv.appendTo(document.body);
+		document.body.classList.add(containerCssClass);
 	}
 
 	private onTouchStart(event: GestureEvent): void {

src/vs/editor/browser/widget/diffEditorWidget.ts

@@ -1327,9 +1327,10 @@ class DiffEdtorWidgetSideBySide extends DiffEditorWidgetStyle implements IDiffEd
 			this._sash.disable();
 		}
 
-		this._sash.on('start', () => this._onSashDragStart());
-		this._sash.on('change', (e: ISashEvent) => this._onSashDrag(e));
-		this._sash.on('end', () => this._onSashDragEnd());
+		this._sash.on('start', () => this.onSashDragStart());
+		this._sash.on('change', (e: ISashEvent) => this.onSashDrag(e));
+		this._sash.on('end', () => this.onSashDragEnd());
+		this._sash.on('reset', () => this.onSashReset());
 	}
 
 	public dispose(): void {
@@ -1378,11 +1379,11 @@ class DiffEdtorWidgetSideBySide extends DiffEditorWidgetStyle implements IDiffEd
 		return this._sashPosition;
 	}
 
-	private _onSashDragStart(): void {
+	private onSashDragStart(): void {
 		this._startSashPosition = this._sashPosition;
 	}
 
-	private _onSashDrag(e:ISashEvent): void {
+	private onSashDrag(e:ISashEvent): void {
 		var w = this._dataSource.getWidth();
 		var contentWidth = w - DiffEditorWidget.ENTIRE_DIFF_OVERVIEW_WIDTH;
 		var sashPosition = this.layout((this._startSashPosition + (e.currentX - e.startX)) / contentWidth);
@@ -1392,7 +1393,13 @@ class DiffEdtorWidgetSideBySide extends DiffEditorWidgetStyle implements IDiffEd
 		this._dataSource.relayoutEditors();
 	}
 
-	private _onSashDragEnd(): void {
+	private onSashDragEnd(): void {
+		this._sash.layout();
+	}
+
+	private onSashReset(): void {
+		this._sashRatio = 0.5;
+		this._dataSource.relayoutEditors();
 		this._sash.layout();
 	}
 

src/vs/workbench/browser/layout.ts

@@ -12,6 +12,7 @@ import {Sash, ISashEvent, IVerticalSashLayoutProvider, IHorizontalSashLayoutProv
 import {IWorkbenchEditorService} from 'vs/workbench/services/editor/common/editorService';
 import {IPartService, Position} from 'vs/workbench/services/part/common/partService';
 import {IWorkspaceContextService} from 'vs/workbench/services/workspace/common/contextService';
+import {IViewletService} from 'vs/workbench/services/viewlet/common/viewletService';
 import {IStorageService, StorageScope} from 'vs/platform/storage/common/storage';
 import {IContextViewService} from 'vs/platform/contextview/browser/contextView';
 import {IEventService} from 'vs/platform/event/common/event';
@@ -94,6 +95,7 @@ export class WorkbenchLayout implements IVerticalSashLayoutProvider, IHorizontal
 		@IWorkbenchEditorService private editorService: IWorkbenchEditorService,
 		@IWorkspaceContextService private contextService: IWorkspaceContextService,
 		@IPartService private partService: IPartService,
+		@IViewletService private viewletService: IViewletService,
 		@IThemeService themeService: IThemeService
 	) {
 		this.parent = parent;
@@ -190,7 +192,7 @@ export class WorkbenchLayout implements IVerticalSashLayoutProvider, IHorizontal
 					let dragCompensation = DEFAULT_MIN_PANEL_PART_HEIGHT - HIDE_PANEL_HEIGHT_THRESHOLD;
 					this.partService.setPanelHidden(true);
 					startY = Math.min(this.sidebarHeight - this.computedStyles.statusbar.height, e.currentY + dragCompensation);
-					this.panelHeight = this.startPanelHeight; // when restoring panel, restore to the panel width we started from
+					this.panelHeight = this.startPanelHeight; // when restoring panel, restore to the panel height we started from
 				}
 
 				// Otherwise size the panel accordingly
@@ -217,9 +219,26 @@ export class WorkbenchLayout implements IVerticalSashLayoutProvider, IHorizontal
 		this.sashX.addListener('end', () => {
 			this.storageService.store(WorkbenchLayout.sashXWidthSettingsKey, this.sidebarWidth, StorageScope.GLOBAL);
 		});
+
 		this.sashY.addListener('end', () => {
 			this.storageService.store(WorkbenchLayout.sashYHeightSettingsKey, this.panelHeight, StorageScope.GLOBAL);
 		});
+
+		this.sashY.addListener('reset', () => {
+			this.panelHeight = DEFAULT_MIN_PANEL_PART_HEIGHT;
+			this.storageService.store(WorkbenchLayout.sashYHeightSettingsKey, this.panelHeight, StorageScope.GLOBAL);
+			this.partService.setPanelHidden(false);
+			this.layout();
+		});
+
+		this.sashX.addListener('reset', () => {
+			let activeViewlet = this.viewletService.getActiveViewlet();
+			let optimalWidth = activeViewlet && activeViewlet.getOptimalWidth();
+			this.sidebarWidth = Math.max(DEFAULT_MIN_PART_WIDTH, optimalWidth || 0);
+			this.storageService.store(WorkbenchLayout.sashXWidthSettingsKey, this.sidebarWidth, StorageScope.GLOBAL);
+			this.partService.setSideBarHidden(false);
+			this.layout();
+		});
 	}
 
 	private onEditorInputChanging(e: EditorEvent): void {

src/vs/workbench/browser/parts/editor/binaryDiffEditor.ts

@@ -72,6 +72,7 @@ export class BinaryResourceDiffEditor extends BaseEditor implements IVerticalSas
 		this.sash.addListener('start', () => this.onSashDragStart());
 		this.sash.addListener('change', (e: ISashEvent) => this.onSashDrag(e));
 		this.sash.addListener('end', () => this.onSashDragEnd());
+		this.sash.addListener('reset', () => this.onSashReset());
 
 		// Right Container for Binary
 		let rightBinaryContainerElement = document.createElement('div');
@@ -199,6 +200,12 @@ export class BinaryResourceDiffEditor extends BaseEditor implements IVerticalSas
 		this.sash.layout();
 	}
 
+	private onSashReset(): void {
+		this.leftContainerWidth = this.dimension.width / 2;
+		this.layoutContainers();
+		this.sash.layout();
+	}
+
 	public getVerticalSashTop(sash: Sash): number {
 		return 0;
 	}

src/vs/workbench/browser/parts/editor/sideBySideEditorControl.ts

@@ -728,6 +728,7 @@ export class SideBySideEditorControl extends EventEmitter implements IVerticalSa
 		this.leftSash.addListener('start', () => this.onLeftSashDragStart());
 		this.leftSash.addListener('change', (e: ISashEvent) => this.onLeftSashDrag(e));
 		this.leftSash.addListener('end', () => this.onLeftSashDragEnd());
+		this.leftSash.addListener('reset', () => this.onLeftSashReset());
 		this.leftSash.hide();
 
 		// Center Container
@@ -738,6 +739,7 @@ export class SideBySideEditorControl extends EventEmitter implements IVerticalSa
 		this.rightSash.addListener('start', () => this.onRightSashDragStart());
 		this.rightSash.addListener('change', (e: ISashEvent) => this.onRightSashDrag(e));
 		this.rightSash.addListener('end', () => this.onRightSashDragEnd());
+		this.rightSash.addListener('reset', () => this.onRightSashReset());
 		this.rightSash.hide();
 
 		// Right Container
@@ -1212,6 +1214,14 @@ export class SideBySideEditorControl extends EventEmitter implements IVerticalSa
 		this.editorActionsToolbar[position].setActions([], [])();
 	}
 
+	private centerSash(a: Position, b: Position): void {
+		let sumWidth = this.containerWidth[a] + this.containerWidth[b];
+		let meanWidth = sumWidth / 2;
+		this.containerWidth[a] = meanWidth;
+		this.containerWidth[b] = sumWidth - meanWidth;
+		this.layoutContainers();
+	}
+
 	private onLeftSashDragStart(): void {
 		this.startLeftContainerWidth = this.containerWidth[Position.LEFT];
 	}
@@ -1301,6 +1311,11 @@ export class SideBySideEditorControl extends EventEmitter implements IVerticalSa
 		this.focusNextNonMinimized();
 	}
 
+	private onLeftSashReset(): void {
+		this.centerSash(Position.LEFT, Position.CENTER);
+		this.leftSash.layout();
+	}
+
 	private onRightSashDragStart(): void {
 		this.startRightContainerWidth = this.containerWidth[Position.RIGHT];
 	}
@@ -1358,6 +1373,11 @@ export class SideBySideEditorControl extends EventEmitter implements IVerticalSa
 		this.focusNextNonMinimized();
 	}
 
+	private onRightSashReset(): void {
+		this.centerSash(Position.CENTER, Position.RIGHT);
+		this.rightSash.layout();
+	}
+
 	public getVerticalSashTop(sash: Sash): number {
 		return 0;
 	}

src/vs/workbench/browser/parts/sidebar/sidebarPart.ts

@@ -78,7 +78,7 @@ export class SidebarPart extends CompositePart<Viewlet> implements IViewletServi
 	}
 
 	public getActiveViewlet(): IViewlet {
-		return this.getActiveComposite();
+		return <IViewlet>this.getActiveComposite();
 	}
 
 	public getLastActiveViewletId(): string {

src/vs/workbench/browser/viewlet.ts

@@ -25,7 +25,11 @@ import {IContextMenuService} from 'vs/platform/contextview/browser/contextView';
 import {IMessageService} from 'vs/platform/message/common/message';
 import {StructuredSelection} from 'vs/platform/selection/common/selection';
 
-export abstract class Viewlet extends Composite implements IViewlet { }
+export abstract class Viewlet extends Composite implements IViewlet {
+	public getOptimalWidth(): number {
+		return null;
+	}
+}
 
 /**
  * Helper subtype of viewlet for those that use a tree inside.

src/vs/workbench/common/viewlet.ts

@@ -5,4 +5,9 @@
 
 import {IComposite} from 'vs/workbench/common/composite';
 
-export interface IViewlet extends IComposite { }
+export interface IViewlet extends IComposite {
+	/**
+	 * Returns the minimal width needed to avoid any content horizontal truncation
+	 */
+	getOptimalWidth(): number;
+}

src/vs/workbench/parts/files/browser/explorerViewlet.ts

@@ -175,6 +175,15 @@ export class ExplorerViewlet extends Viewlet {
 		return this.actionRunner;
 	}
 
+	public getOptimalWidth(): number {
+		let additionalMargin = 16;
+		let workingFilesViewWidth = this.getWorkingFilesView().getOptimalWidth();
+		let explorerView = this.getExplorerView();
+		let explorerViewWidth = explorerView ? explorerView.getOptimalWidth() : 0;
+		let optimalWidth = Math.max(workingFilesViewWidth, explorerViewWidth);
+		return optimalWidth + additionalMargin;
+	}
+
 	public shutdown(): void {
 		this.views.forEach((view) => view.shutdown());
 

src/vs/workbench/parts/files/browser/views/explorerView.ts

@@ -24,7 +24,7 @@ import {FileEditorInput} from 'vs/workbench/parts/files/browser/editors/fileEdit
 import {FileDragAndDrop, FileFilter, FileSorter, FileController, FileRenderer, FileDataSource, FileViewletState, FileAccessibilityProvider} from 'vs/workbench/parts/files/browser/views/explorerViewer';
 import lifecycle = require('vs/base/common/lifecycle');
 import {IEditor} from 'vs/platform/editor/common/editor';
-import DOM = require('vs/base/browser/dom');
+import * as DOM from 'vs/base/browser/dom';
 import {CollapseAction, CollapsibleViewletView} from 'vs/workbench/browser/viewlet';
 import {FileStat} from 'vs/workbench/parts/files/common/explorerViewModel';
 import {IWorkbenchEditorService} from 'vs/workbench/services/editor/common/editorService';
@@ -348,6 +348,12 @@ export class ExplorerView extends CollapsibleViewletView {
 		return this.explorerViewer;
 	}
 
+	public getOptimalWidth(): number {
+		let parentNode = this.explorerViewer.getHTMLElement();
+		let childNodes = [].slice.call(parentNode.querySelectorAll('.explorer-item-label > a'));
+		return DOM.getLargestChildWidth(parentNode, childNodes);
+	}
+
 	private onLocalFileChange(e: LocalFileChangeEvent): void {
 		let modelElement: FileStat;
 		let parent: FileStat;