bug fix and performance improvements

miniprogram/miniprogram_npm/tdesign-miniprogram/dropdown-menu/props.js

@@ -0,0 +1,26 @@
+const props = {
+    arrowIcon: {
+        type: null,
+        value: 'caret-down-small',
+    },
+    closeOnClickOverlay: {
+        type: Boolean,
+        value: true,
+    },
+    duration: {
+        type: null,
+        value: 200,
+    },
+    externalClasses: {
+        type: Array,
+    },
+    showOverlay: {
+        type: Boolean,
+        value: true,
+    },
+    zIndex: {
+        type: Number,
+        value: 11600,
+    },
+};
+export default props;