(core) Forms improvements: mouse selection in firefox, focus, and styling

Summary:
- Remove unused Form file (Label.ts)
- Fix Firefox-specific bug in Forms, where mouse selection wasn't working in textarea.
- Focus and set cursor in textarea on click.
- Save on blur but only when focus stays within the Grist app, as for editing cells.
- Make paragraph margins of rendered form match those in the form editor.

Test Plan: Tested manually on Firefox and Chrome; relying on existing tests that nothing broke.

Reviewers: jarek

Reviewed By: jarek

Differential Revision: https://phab.getgrist.com/D4281

app/client/components/Forms/Editor.ts

@@ -22,10 +22,6 @@ interface Props {
    * Actual element to put into the editor. This is the main content of the editor.
    */
   content: DomContents,
-  /**
-   * Click handler. If not provided, then clicking on the editor will select it.
-   */
-  click?: (ev: MouseEvent, box: BoxModel) => void,
   /**
    * Whether to show the remove button. Defaults to true.
    */
@@ -75,22 +71,6 @@ export function buildEditor(props: Props, ...args: IDomArgs<HTMLElement>) {
     style.cssRemoveButton.cls('-right', props.removePosition === 'right'),
   );
 
-  const onClick = (ev: MouseEvent) => {
-    // Only if the click was in this element.
-    const target = ev.target as HTMLElement;
-    if (!target.closest) { return; }
-    // Make sure that the closest editor is this one.
-    const closest = target.closest(`.${style.cssFieldEditor.className}`);
-    if (closest !== element) { return; }
-
-    ev.stopPropagation();
-    ev.preventDefault();
-    props.click?.(ev, props.box);
-
-    // Mark this box as selected.
-    box.view.selectedBox.set(box);
-  };
-
   const dragAbove = Observable.create(owner, false);
   const dragBelow = Observable.create(owner, false);
   const dragging = Observable.create(owner, false);
@@ -111,7 +91,10 @@ export function buildEditor(props: Props, ...args: IDomArgs<HTMLElement>) {
     testId('field-editor-selected', box.selected),
 
     // Select on click.
-    dom.on('click', onClick),
+    dom.on('click', (ev) => {
+      stopEvent(ev);
+      box.view.selectedBox.set(box);
+    }),
 
     // Attach context menu.
     buildMenu({
@@ -122,6 +105,15 @@ export function buildEditor(props: Props, ...args: IDomArgs<HTMLElement>) {
     // And now drag and drop support.
     {draggable: "true"},
 
+    // In Firefox, 'draggable' interferes with mouse selection in child input elements. Workaround
+    // is to turn off 'draggable' temporarily (see https://stackoverflow.com/q/21680363/328565).
+    dom.on('mousedown', (ev, elem) => {
+      const isInput = ["INPUT", "TEXTAREA"].includes((ev.target as Element)?.tagName);
+      // Turn off 'draggable' for inputs only, to support selection there; keep it on elsewhere.
+      elem.draggable = !isInput;
+    }),
+    dom.on('mouseup', (ev, elem) => { elem.draggable = true; }),
+
     // When started, we just put the box into the dataTransfer as a plain text.
     // TODO: this might be very sofisticated in the future.
     dom.on('dragstart', (ev) => {

app/client/components/Forms/Label.ts

@@ -1,85 +0,0 @@
-import * as css from './styles';
-import {buildEditor} from 'app/client/components/Forms/Editor';
-import {BoxModel} from 'app/client/components/Forms/Model';
-import {stopEvent} from 'app/client/lib/domUtils';
-import {not} from 'app/common/gutil';
-import {Computed, dom, Observable} from 'grainjs';
-
-export class LabelModel extends BoxModel {
-  public edit = Observable.create(this, false);
-
-  protected defaultValue = '';
-
-  public render(): HTMLElement {
-    let element: HTMLTextAreaElement;
-    const text = this.prop('text', this.defaultValue) as Observable<string|undefined>;
-    const cssClass = this.prop('cssClass', '') as Observable<string>;
-    const editableText = Observable.create(this, text.get() || '');
-    const overlay = Computed.create(this, use => !use(this.edit));
-
-    this.autoDispose(text.addListener((v) => editableText.set(v || '')));
-
-    const save = (ok: boolean) => {
-      if (ok) {
-        text.set(editableText.get());
-        void this.parent?.save().catch(reportError);
-      } else {
-        editableText.set(text.get() || '');
-      }
-    };
-
-    const mode = (edit: boolean) => {
-      if (this.isDisposed() || this.edit.isDisposed()) { return; }
-      if (this.edit.get() === edit) { return; }
-      this.edit.set(edit);
-    };
-
-    return buildEditor(
-      {
-        box: this,
-        editMode: this.edit,
-        overlay,
-        click: (ev) => {
-          stopEvent(ev);
-          // If selected, then edit.
-          if (!this.selected.get()) { return; }
-          if (document.activeElement === element) { return; }
-          editableText.set(text.get() || '');
-          this.edit.set(true);
-          setTimeout(() => {
-            element.focus();
-            element.select();
-          }, 10);
-        },
-        content: element = css.cssEditableLabel(
-          editableText,
-          {onInput: true, autoGrow: true},
-          {placeholder: `Empty label`},
-          dom.on('click', ev => {
-            stopEvent(ev);
-          }),
-          // Styles saved (for titles and such)
-          css.cssEditableLabel.cls(use => `-${use(cssClass)}`),
-          // Disable editing if not in edit mode.
-          dom.boolAttr('readonly', not(this.edit)),
-          // Pass edit to css.
-          css.cssEditableLabel.cls('-edit', this.edit),
-          // Attach default save controls (Enter, Esc) and so on.
-          css.saveControls(this.edit, save),
-          // Turn off resizable for textarea.
-          dom.style('resize', 'none'),
-        ),
-      },
-      dom.onKeyDown({Enter$: (ev) => {
-        // If no in edit mode, change it.
-        if (!this.edit.get()) {
-          mode(true);
-          ev.stopPropagation();
-          ev.stopImmediatePropagation();
-          ev.preventDefault();
-          return;
-        }
-      }})
-    );
-  }
-}

app/client/components/Forms/Paragraph.ts

@@ -19,7 +19,6 @@ export class ParagraphModel extends BoxModel {
   public override render(): HTMLElement {
     const box = this;
     const editMode = box.edit;
-    let element: HTMLElement;
     const text = this.prop('text', this.defaultValue) as Observable<string|undefined>;
 
     // There is a spacial hack here. We might be created as a separator component, but the rendering
@@ -44,18 +43,21 @@ export class ParagraphModel extends BoxModel {
         this.cssClass ? dom.cls(this.cssClass, not(editMode)) : null,
         dom.maybe(editMode, () => {
           const draft = Observable.create(null, text.get() || '');
-          setTimeout(() => element?.focus(), 10);
-          return [
-            element = cssTextArea(draft, {autoGrow: true, onInput: true},
+          return cssTextArea(draft, {autoGrow: true, onInput: true},
             cssTextArea.cls('-edit', editMode),
+            (elem) => {
+              setTimeout(() => {
+                elem.focus();
+                elem.setSelectionRange(elem.value.length, elem.value.length);
+              }, 10);
+            },
             css.saveControls(editMode, (ok) => {
               if (ok && editMode.get()) {
                 text.set(draft.get());
                 this.save().catch(reportError);
               }
             })
-            ),
-          ];
+          );
         }),
       )
     });

app/client/components/Forms/elements.ts

@@ -13,7 +13,6 @@ export * from "./Section";
 export * from './Field';
 export * from './Columns';
 export * from './Submit';
-export * from './Label';
 
 export function defaultElement(type: FormLayoutNodeType): FormLayoutNode {
   switch(type) {

app/client/components/Forms/styles.ts

@@ -1,3 +1,4 @@
+import type {App} from 'app/client/ui/App';
 import {textarea} from 'app/client/ui/inputs';
 import {sanitizeHTML} from 'app/client/ui/sanitizeHTML';
 import {basicButton, basicButtonLink, primaryButtonLink, textButton} from 'app/client/ui2018/buttons';
@@ -759,11 +760,17 @@ export function saveControls(editMode: Observable<boolean>, save: (ok: boolean)
         }
       }
     }),
-    dom.on('blur', (ev) => {
+    dom.create((owner) => {
+      // Whenever focus returns to the Clipboard component, close the editor by saving the value.
+      function saveEdit() {
         if (!editMode.isDisposed() && editMode.get()) {
           save(true);
           editMode.set(false);
         }
+      }
+      const app = (window as any).gristApp as App;
+      app.on('clipboard_focus', saveEdit);
+      owner.onDispose(() => app.off('clipboard_focus', saveEdit));
     }),
   ];
 }

app/client/ui/FormPage.ts

@@ -165,7 +165,7 @@ const cssFormContent = styled('form', `
     font-size: 10px;
   }
   & p {
-    margin: 0px;
+    margin: 0 0 10px 0;
   }
   & strong {
     font-weight: 600;