Made several widgets more keyboard-friendly.

src/core/gui/Button.css

@@ -39,6 +39,10 @@
     color: hsl(0, 0%, 75%);
 }
 
+.core_Button:focus-within .core_Button_inner {
+    border: var(--control-inner-border-focus);
+}
+
 .core_Button:disabled .core_Button_inner {
     background-color: hsl(0, 0%, 15%);
     border-color: hsl(0, 0%, 25%);

src/core/gui/Button.ts

@@ -19,6 +19,8 @@ export class Button extends Control {
     private readonly _mousedown: Emitter<MouseEvent>;
     private readonly _mouseup: Emitter<MouseEvent>;
     private readonly _click: Emitter<MouseEvent>;
+    private readonly _keydown: Emitter<KeyboardEvent>;
+    private readonly _keyup: Emitter<KeyboardEvent>;
     private readonly _text: WidgetProperty<string>;
     private readonly center_element: HTMLSpanElement;
 
@@ -26,6 +28,8 @@ export class Button extends Control {
     readonly mousedown: Observable<MouseEvent>;
     readonly mouseup: Observable<MouseEvent>;
     readonly click: Observable<MouseEvent>;
+    readonly keydown: Observable<KeyboardEvent>;
+    readonly keyup: Observable<KeyboardEvent>;
     readonly text: WritableProperty<string>;
 
     constructor(options?: ButtonOptions) {
@@ -58,6 +62,14 @@ export class Button extends Control {
         this.click = this._click;
         this.element.onclick = (e: MouseEvent) => this._click.emit({ value: e });
 
+        this._keydown = emitter<KeyboardEvent>();
+        this.keydown = this._keydown;
+        this.element.onkeydown = (e: KeyboardEvent) => this._keydown.emit({ value: e });
+
+        this._keyup = emitter<KeyboardEvent>();
+        this.keyup = this._keyup;
+        this.element.onkeyup = (e: KeyboardEvent) => this._keyup.emit({ value: e });
+
         this._text = new WidgetProperty<string>(this, "", this.set_text);
         this.text = this._text;
 

src/core/gui/DropDown.ts

@@ -35,7 +35,7 @@ export class DropDown<T> extends Control {
             }),
         );
         this.menu = this.disposable(
-            new Menu<T>({
+            new Menu({
                 items: options.items,
                 to_label: options.to_label,
                 related_element: this.element,
@@ -49,11 +49,13 @@ export class DropDown<T> extends Control {
         this.just_opened = false;
 
         this.disposables(
-            disposable_listener(this.button.element, "mousedown", () => this.button_mousedown(), {
+            disposable_listener(this.button.element, "mousedown", this.button_mousedown, {
                 capture: true,
             }),
 
-            this.button.mouseup.observe(() => this.button_mouseup()),
+            this.button.mouseup.observe(this.button_mouseup),
+
+            this.button.keydown.observe(this.button_keydown),
 
             this.menu.selected.observe(({ value }) => {
                 if (value !== undefined) {
@@ -71,12 +73,12 @@ export class DropDown<T> extends Control {
         this.button.enabled.val = enabled;
     }
 
-    private button_mousedown(): void {
+    private button_mousedown = (): void => {
         this.just_opened = !this.menu.visible.val;
         this.menu.visible.val = true;
-    }
+    };
 
-    private button_mouseup(): void {
+    private button_mouseup = (): void => {
         if (this.just_opened) {
             this.menu.focus();
         } else {
@@ -84,5 +86,15 @@ export class DropDown<T> extends Control {
         }
 
         this.just_opened = false;
+    };
+
+    private button_keydown = ({ value: evt }: { value: KeyboardEvent }): void => {
+        if (evt.key === "Enter" || evt.key === " ") {
+            evt.preventDefault();
+            this.just_opened = !this.menu.visible.val;
+            this.menu.visible.val = true;
+            this.menu.focus();
+            this.menu.hover_next();
         }
+    };
 }

src/core/gui/Menu.ts

@@ -23,6 +23,7 @@ export class Menu<T> extends Widget {
     private readonly _selected: WidgetProperty<T | undefined>;
     private hovered_index?: number;
     private hovered_element?: HTMLElement;
+    private previously_focused_element?: Element;
 
     constructor(options: MenuOptions<T>) {
         super();
@@ -31,6 +32,7 @@ export class Menu<T> extends Widget {
 
         this.element.onmouseup = this.mouseup;
         this.element.onkeydown = this.keydown;
+        this.element.onblur = this.blur;
 
         this.inner_element.onmouseover = this.inner_mouseover;
         this.element.append(this.inner_element);
@@ -66,6 +68,11 @@ export class Menu<T> extends Widget {
         this.finalize_construction();
     }
 
+    focus(): void {
+        this.previously_focused_element = document.activeElement ?? undefined;
+        this.element.focus();
+    }
+
     hover_next(): void {
         this.visible.set_val(true, { silent: false });
         this.hover_item(
@@ -90,6 +97,10 @@ export class Menu<T> extends Widget {
         if (this.visible.val != visible) {
             this.hover_item();
             this.inner_element.scrollTop = 0;
+
+            if (!visible && this.previously_focused_element instanceof HTMLElement) {
+                this.previously_focused_element.focus();
+            }
         }
     }
 
@@ -106,24 +117,31 @@ export class Menu<T> extends Widget {
         this.select_item(parseInt(index_str, 10));
     };
 
-    private keydown = (e: Event): void => {
+    private keydown = (evt: Event): void => {
-        const key = (e as KeyboardEvent).key;
+        const key = (evt as KeyboardEvent).key;
 
         switch (key) {
             case "ArrowDown":
+                evt.preventDefault();
                 this.hover_next();
                 break;
 
             case "ArrowUp":
+                evt.preventDefault();
                 this.hover_prev();
                 break;
 
             case "Enter":
+                evt.preventDefault();
                 this.select_hovered();
                 break;
         }
     };
 
+    private blur = (): void => {
+        this.visible.val = false;
+    };
+
     private inner_mouseover = (e: Event): void => {
         if (e.target && e.target instanceof HTMLElement) {
             const index = e.target.dataset.index;

src/core/gui/Select.ts

@@ -53,13 +53,15 @@ export class Select<T> extends LabelledControl {
         this.just_opened = false;
 
         this.disposables(
-            disposable_listener(this.button.element, "mousedown", e => this.button_mousedown(e)),
+            disposable_listener(this.button.element, "mousedown", this.button_mousedown),
 
-            this.button.mouseup.observe(() => this.button_mouseup()),
+            this.button.mouseup.observe(this.button_mouseup),
 
-            this.menu.selected.observe(({ value }) =>
+            this.button.keydown.observe(this.button_keydown),
-                this._selected.set_val(value, { silent: false }),
+
-            ),
+            this.menu.selected.observe(({ value }) => {
+                this._selected.set_val(value, { silent: false });
+            }),
         );
 
         if (options) {
@@ -83,13 +85,13 @@ export class Select<T> extends LabelledControl {
         this.menu.selected.val = selected;
     }
 
-    private button_mousedown(e: Event): void {
+    private button_mousedown = (e: Event): void => {
         e.stopPropagation();
         this.just_opened = !this.menu.visible.val;
         this.menu.visible.val = true;
-    }
+    };
 
-    private button_mouseup(): void {
+    private button_mouseup = (): void => {
         if (this.just_opened) {
             this.menu.focus();
         } else {
@@ -97,5 +99,15 @@ export class Select<T> extends LabelledControl {
         }
 
         this.just_opened = false;
+    };
+
+    private button_keydown = ({ value: evt }: { value: KeyboardEvent }): void => {
+        if (evt.key === "Enter" || evt.key === " ") {
+            evt.preventDefault();
+            this.just_opened = !this.menu.visible.val;
+            this.menu.visible.val = true;
+            this.menu.focus();
+            this.menu.hover_next();
         }
+    };
 }

src/core/gui/index.css

@@ -22,6 +22,7 @@
     --control-border: solid 1px hsl(0, 0%, 10%);
 
     --control-inner-border: solid 1px hsl(0, 0%, 35%);
+    --control-inner-border-focus: solid 1px hsl(0, 0%, 50%);
 
     /* Inputs */
 

version.txt

@@ -1 +1 @@
-35
+36