MDL-74054 questions: Fix question bank header widths

Chrome ignores min-width on table headers with table-layout:fixed,
meaning that question bank headers could be resized so that the controls
were overlapping, and could be too narrow by default.

This removes min-width: min-content in the headers and instead uses
Javascript to calculate a constrain a min width based on the content of
the headers.

question/bank/columnsortorder/amd/src/user_actions.js

@@ -48,6 +48,9 @@ let currentHeader;
 /** Current mouse x postion, to track mouse event on a table header */
 let currentX;
 
+/** Minimum size for the column currently being resized. */
+let currentMin;
+
 /**
  * Flag to temporarily prevent move and resize handles from being shown or hidden.
  *
@@ -129,6 +132,21 @@ const serialiseColumnSizes = (uiRoot) => {
     return JSON.stringify(columnSizes);
 };
 
+/**
+ * Find the minimum width for a header, based on the width of its contents.
+ *
+ * This is to simulate `min-width: min-content;`, which doesn't work on Chrome because
+ * min-width is ignored width `table-layout: fixed;`.
+ *
+ * @param {Element} header The table header
+ * @return {Number} The minimum width in pixels
+ */
+const getMinWidth = (header) => {
+    const contents = Array.from(header.querySelector('.header-text').children);
+    const contentWidth = contents.reduce((width, contentElement) => width + contentElement.getBoundingClientRect().width, 0);
+    return Math.ceil(contentWidth);
+};
+
 /**
  * Render resize handles in each container.
  *
@@ -141,6 +159,11 @@ const setUpResizeHandles = (uiRoot) => {
     const resizeActions = uiRoot.querySelectorAll(SELECTORS.resizeAction);
     resizeActions.forEach(resizeAction => {
         const headerContainer = resizeAction.closest(SELECTORS.headerContainer);
+        const header = resizeAction.closest(actions.SELECTORS.sortableColumn);
+        const minWidth = getMinWidth(header);
+        if (header.offsetWidth < minWidth) {
+            header.style.width = minWidth + 'px';
+        }
         const handleContainer = headerContainer.querySelector(SELECTORS.handleContainer);
         const context = {
             action: "resize",
@@ -170,6 +193,7 @@ const setUpResizeHandles = (uiRoot) => {
         currentX = e.pageX;
         // Find the header.
         currentHeader = e.target.closest(actions.SELECTORS.sortableColumn);
+        currentMin = getMinWidth(currentHeader);
         moveTracker = false;
         suspendShowHideHandles = true;
     });
@@ -187,7 +211,9 @@ const setUpResizeHandles = (uiRoot) => {
         const offset = e.pageX - currentX;
         currentX = e.pageX;
         const newWidth = currentHeader.offsetWidth + offset;
+        if (newWidth >= currentMin) {
             currentHeader.style.width = newWidth + 'px';
+        }
         moveTracker = true;
     });
 
@@ -203,6 +229,7 @@ const setUpResizeHandles = (uiRoot) => {
             // If the mouse didn't move, display a modal to change the size using a form.
             showResizeModal(currentHeader, uiRoot);
         }
+        currentMin = null;
         currentHeader = null;
         currentResizeHandle = null;
         currentX = 0;
@@ -238,10 +265,11 @@ const setUpResizeActions = uiRoot => {
  */
 const showResizeModal = async(currentHeader, uiRoot) => {
     const initialWidth = currentHeader.offsetWidth;
+    const minWidth = getMinWidth(currentHeader);
 
     const modal = await ModalSaveCancel.create({
         title: getString('resizecolumn', 'qbank_columnsortorder', currentHeader.textContent),
-        body: Templates.render('qbank_columnsortorder/resize_modal', {}),
+        body: Templates.render('qbank_columnsortorder/resize_modal', {width: initialWidth, min: minWidth}),
         show: true,
     });
     const root = modal.getRoot();
@@ -254,11 +282,14 @@ const showResizeModal = async(currentHeader, uiRoot) => {
 
     const body = await modal.bodyPromise;
     const input = body.get(0).querySelector('input');
-    input.value = initialWidth;
 
     input.addEventListener('change', e => {
+        const valid = e.target.checkValidity();
+        e.target.closest('.has-validation').classList.add('was-validated');
+        if (valid) {
             const newWidth = e.target.value;
             currentHeader.style.width = `${newWidth}px`;
+        }
     });
 };
 

question/bank/columnsortorder/classes/output/column_sort_ui.php

@@ -35,9 +35,14 @@ use templatable;
  */
 class column_sort_ui implements renderable, templatable {
     /**
-     * @var int The minimum custom width for a column.
+     * The minimum custom width for a column.
+     *
+     * This is based on the minimum possible width of the smallest core column (question type).
+     * When viewed, the width will be resized to the minimum width of the column header, if too small.
+     *
+     * @var int
      */
-    const MIN_COLUMN_WIDTH = 10;
+    const MIN_COLUMN_WIDTH = 30;
 
     public function export_for_template(\renderer_base $output): array {
         $columnmanager = new column_manager(true);

question/bank/columnsortorder/lang/en/qbank_columnsortorder.php

@@ -27,7 +27,7 @@ $string['addcolumn'] = 'Add column \'{$a}\'';
 $string['addcolumns'] = 'Add columns';
 $string['auto'] = 'Auto';
 $string['columnwidth'] = 'Column width (pixels)';
-$string['invalidwidth'] = 'Width must be at least 10.';
+$string['invalidwidth'] = 'Width must be at least {$a}.';
 $string['movecolumn'] = 'Move column \'{$a}\'';
 $string['pluginname'] = 'Column sort order';
 $string['privacy:metadata:preference:enabledcol'] = 'The plugin saves user preference of column orders.';

question/bank/columnsortorder/templates/column_sort_ui.mustache

@@ -149,7 +149,7 @@
                                     {{#str}}save{{/str}}
                                 </button>
                                 <div class="invalid-feedback">
-                                    {{#str}}invalidwidth, qbank_columnsortorder{{/str}}
+                                    {{#str}}invalidwidth, qbank_columnsortorder, {{minwidth}}{{/str}}
                                 </div>
                             </div>
                         </td>

question/bank/columnsortorder/templates/resize_modal.mustache

@@ -23,7 +23,11 @@
     {
     }
 }}
-<label>
-    {{#str}}columnwidth, qbank_columnsortorder{{/str}}
-    <input name="columnwidth" type="number" value="">
-</label>
+<form class="has-validation">
+    <label for="columnwidth">{{#str}}columnwidth, qbank_columnsortorder{{/str}}</label>
+    <input class="form-control" id="columnwidth" type="number" value="{{width}}" min="{{min}}">
+    <div class="invalid-feedback">
+        {{#str}}invalidwidth, qbank_columnsortorder, {{min}}{{/str}}
+    </div>
+</form>
+

question/classes/local/bank/checkbox_column.php

@@ -97,6 +97,6 @@ class checkbox_column extends column_base {
     }
 
     public function get_default_width(): int {
-        return 25;
+        return 30;
     }
 }

theme/boost/scss/moodle/question.scss

@@ -189,7 +189,6 @@ table.question-bank-table {
 
     .header {
         text-align: left;
-        min-width: min-content;
 
         &.sortable-list-current-position {
             background-color: lighten($primary, 40%);
@@ -206,6 +205,9 @@ table.question-bank-table {
         .dropdown-toggle::after {
             margin-left: 0;
         }
+        &.checkbox .form-check {
+            padding-left: 0;
+        }
     }
 }
 

theme/boost/style/moodle.css

@@ -32054,7 +32054,6 @@ table.question-bank-table label {
 }
 table.question-bank-table .header {
   text-align: left;
-  min-width: min-content;
 }
 table.question-bank-table .header.sortable-list-current-position {
   background-color: #a2cff8;
@@ -32069,6 +32068,9 @@ table.question-bank-table .header .header-text > div {
 table.question-bank-table .header .dropdown-toggle::after {
   margin-left: 0;
 }
+table.question-bank-table .header.checkbox .form-check {
+  padding-left: 0;
+}
 
 #page-mod-quiz-edit div.questionbankwindow div.header {
   margin: 0;

theme/classic/style/moodle.css

@@ -32054,7 +32054,6 @@ table.question-bank-table label {
 }
 table.question-bank-table .header {
   text-align: left;
-  min-width: min-content;
 }
 table.question-bank-table .header.sortable-list-current-position {
   background-color: #a2cff8;
@@ -32069,6 +32068,9 @@ table.question-bank-table .header .header-text > div {
 table.question-bank-table .header .dropdown-toggle::after {
   margin-left: 0;
 }
+table.question-bank-table .header.checkbox .form-check {
+  padding-left: 0;
+}
 
 #page-mod-quiz-edit div.questionbankwindow div.header {
   margin: 0;