Add demo for disabling multi selection

CONTRIBUTING.md

@@ -2,6 +2,7 @@
 
 1. Clone the repo
 2. From the root, run yarn start
+3. Visit localhost:3000
 
 # Publishing a Release
 

packages/react-arborist/src/components/default-container.tsx

@@ -132,7 +132,7 @@ export function DefaultContainer() {
           }
           return;
         }
-        if (e.key === "a" && e.metaKey) {
+        if (e.key === "a" && e.metaKey && !tree.props.disableMultiSelection) {
           e.preventDefault();
           tree.selectAll();
           return;

packages/showcase/pages/cities.tsx

@@ -20,6 +20,7 @@ export default function Cities() {
   const [searchTerm, setSearchTerm] = useState("");
   const [count, setCount] = useState(0);
   const [followsFocus, setFollowsFocus] = useState(false);
+  const [disableMulti, setDisableMulti] = useState(false);
 
   useEffect(() => {
     setCount(tree?.visibleNodes.length ?? 0);
@@ -35,6 +36,7 @@ export default function Cities() {
                 {...dimens}
                 initialData={data}
                 selectionFollowsFocus={followsFocus}
+                disableMultiSelection={disableMulti}
                 ref={(t) => setTree(t)}
                 openByDefault={true}
                 searchTerm={searchTerm}
@@ -100,6 +102,16 @@ export default function Cities() {
               onChange={(e) => setFollowsFocus((v) => !v)}
             />
           </section>
+          <section>
+            <label>
+              Demo the <i>disableMultiSelection</i> prop:
+            </label>
+            <input
+              type="checkbox"
+              checked={disableMulti}
+              onChange={(e) => setDisableMulti((v) => !v)}
+            />
+          </section>
           <section>
             <label>
               Demo the <i>tree</i> ref: