ENH MutliLinkField sorting

client/lang/en.js

@@ -21,6 +21,8 @@ if (typeof(ss) === 'undefined' || typeof(ss.i18n) === 'undefined') {
     "LinkField.CANNOT_CREATE_LINK": "Cannot create link",
     "LinkField.FAILED_TO_LOAD_LINKS": "Failed to load links",
     "LinkField.FAILED_TO_SAVE_LINK": "Failed to save link",
-    "LinkField.SAVE_RECORD_FIRST": "Cannot add links until the record has been saved"
+    "LinkField.SAVE_RECORD_FIRST": "Cannot add links until the record has been saved",
+    "LinkField.SORT_SUCCESS": "Updated link sort order",
+    "LinkField.SORT_ERROR": "Unable to sort links"
   });
 }

client/lang/src/en.json

@@ -14,5 +14,7 @@
     "LinkField.CANNOT_CREATE_LINK": "Cannot create link",
     "LinkField.FAILED_TO_LOAD_LINKS": "Failed to load links",
     "LinkField.FAILED_TO_SAVE_LINK": "Failed to save link",
-    "LinkField.SAVE_RECORD_FIRST": "Cannot add links until the record has been saved"
+    "LinkField.SAVE_RECORD_FIRST": "Cannot add links until the record has been saved",
+    "LinkField.SORT_SUCCESS": "Updated link sort order",
+    "LinkField.SORT_ERROR": "Unable to sort links"
 }

client/src/components/LinkField/LinkField.js

@@ -2,6 +2,9 @@
 import React, { useState, useEffect, createContext } from 'react';
 import { bindActionCreators, compose } from 'redux';
 import { connect } from 'react-redux';
+import { DndContext, closestCenter, PointerSensor, useSensor, useSensors } from '@dnd-kit/core';
+import { arrayMove, SortableContext, verticalListSortingStrategy } from '@dnd-kit/sortable';
+import { restrictToVerticalAxis, restrictToParentElement } from '@dnd-kit/modifiers';
 import { injectGraphql } from 'lib/Injector';
 import fieldHolder from 'components/FieldHolder/FieldHolder';
 import LinkPicker from 'components/LinkPicker/LinkPicker';
@@ -47,6 +50,15 @@ const LinkField = ({
   const [data, setData] = useState({});
   const [editingID, setEditingID] = useState(0);
   const [loading, setLoading] = useState(false);
+  const [forceFetch, setForceFetch] = useState(0);
+
+  const sensors = useSensors(
+    useSensor(PointerSensor, {
+      activationConstraint: {
+        distance: 10
+      }
+    })
+  );
 
   // Ensure we have a valid array
   let linkIDs = value;
@@ -61,6 +73,7 @@ const LinkField = ({
 
   // Read data from endpoint and update component state
   // This happens any time a link is added or removed and triggers a re-render
+
   useEffect(() => {
     if (!editingID && linkIDs.length > 0) {
       setLoading(true);
@@ -80,7 +93,7 @@ const LinkField = ({
           setLoading(false);
         });
     }
-  }, [editingID, value && value.length]);
+  }, [editingID, value && value.length, forceFetch]);
 
   /**
    * Unset the editing ID when the editing modal is closed
@@ -172,10 +185,36 @@ const LinkField = ({
     return links;
   };
 
+  /**
+   * Drag and drop handler for MultiLinkField's
+   */
+  const handleDragEnd = (event) => {
+    const {active, over} = event;
+    if (active.id === over.id) {
+      return;
+    }
+    const fromIndex = linkIDs.indexOf(active.id);
+    const toIndex = linkIDs.indexOf(over.id);
+    const newLinkIDs = arrayMove(linkIDs, fromIndex, toIndex);
+    let endpoint = `${Config.getSection(section).form.linkForm.sortUrl}`;
+    // CSRF token 'X-SecurityID' headers needs to be present
+    backend.post(endpoint, { newLinkIDs }, { 'X-SecurityID': Config.get('SecurityID') })
+      .then(() => {
+        onChange(newLinkIDs);
+        actions.toasts.success(i18n._t('LinkField.SORT_SUCCESS', 'Updated link sort order'));
+        // Force a rerender so that links are retched so that versionState badges are up to date
+        setForceFetch(forceFetch + 1);
+      })
+      .catch(() => {
+        actions.toasts.error(i18n._t('LinkField.SORT_ERROR', 'Failed to sort links'));
+      });
+  }
+
   const saveRecordFirst = ownerID === 0;
   const renderPicker = !saveRecordFirst && (isMulti || Object.keys(data).length === 0);
   const renderModal = !saveRecordFirst && Boolean(editingID);
   const saveRecordFirstText = i18n._t('LinkField.SAVE_RECORD_FIRST', 'Cannot add links until the record has been saved');
+  const links = renderLinks();
 
   if (loading && !saveRecordFirst) {
     return <div className="link-field__loading"><Loading/></div>;
@@ -189,7 +228,21 @@ const LinkField = ({
         types={types}
         canCreate={canCreate}
       /> }
-        <div> { renderLinks() } </div>
+    { isMulti && <div>
+      <DndContext modifiers={[restrictToVerticalAxis, restrictToParentElement]}
+        sensors={sensors}
+        collisionDetection={closestCenter}
+        onDragEnd={handleDragEnd}
+      >
+        <SortableContext 
+          items={linkIDs}
+          strategy={verticalListSortingStrategy}
+        >
+          {links}
+        </SortableContext>
+      </DndContext>
+    </div> }
+    { !isMulti && <div>{ renderLinks() }</div>}
     { renderModal && <LinkModalContainer
         types={types}
         typeKey={data[editingID]?.typeKey}

client/src/components/LinkPicker/LinkPicker.scss

@@ -66,11 +66,14 @@
   }
 
   &:hover, &:focus {
-    background: $gray-100;
     text-decoration: none;
     color: inherit;
   }
 
+  &:active {
+    cursor: grabbing;
+  }
+
   // version-state icon
   &::before {
     top: 29px;
@@ -121,6 +124,20 @@
   }
 }
 
+.link-picker__drag-handle {
+  cursor: grab;
+  display: none;
+  left: 5px;
+  position: absolute;
+  z-index: 100;
+}
+
+.link-picker__link:hover {
+  .link-picker__drag-handle {
+    display: block;
+  }
+}
+
 .link-picker__link-detail {
   flex-grow: 1;
   width: 100%;