Feat: Adding Support Placeholder

examples/mirai_gallery/assets/json/home_screen.json

@@ -1555,6 +1555,41 @@
       }
     }
   },
+
+  {
+    "type": "listTile",
+    "leading": {
+      "type": "icon",
+      "iconType": "material",
+      "icon": "apartment"
+    },
+
+    "title": {
+      "type": "text",
+      "data": "Placeholder",
+      "style": {
+        "fontSize": 21
+      }
+    },
+    "subtitle": {
+      "type": "text",
+      "data": "A Material Design Mirai Placeholder widget",
+      "style": {
+        "fontSize": 12
+      }
+    },
+    "isThreeLine": true,
+    "onTap": {
+      "actionType": "navigate",
+      "navigationStyle": "push",
+      "widgetJson": {
+        "type": "exampleScreen",
+        "assetPath": "assets/json/placeholder_example.json"
+      }
+    }
+  },
+
+
   {
     "type": "sizedBox",
     "height": 24.0

examples/mirai_gallery/assets/json/placeholder_example.json

@@ -0,0 +1,37 @@
+{
+  "type": "scaffold",
+  "appBar": {
+    "type": "appBar",
+    "title": {
+      "type": "text",
+      "data": "Placeholder"
+    }
+  },
+  "body": {
+    "type": "listView",
+    "shrinkWrap": true,
+    "children": [
+      {
+        "type": "sizedBox",
+        "height": 25
+      },
+      {
+        "type": "placeholder",
+        "color": "#455A64",
+        "strokeWidth": 2.0,
+        "fallbackHeight": 400.0,
+        "fallbackWidth": 400.0
+      },
+      {
+        "type": "sizedBox",
+        "height": 25
+      },
+      {
+        "color": "#672BFF",
+        "type": "placeholder",
+        "strokeWidth": 5.0,
+        "fallbackHeight": 100.0
+      }
+    ]
+  }
+}

packages/mirai/lib/src/framework/mirai.dart

@@ -91,6 +91,7 @@ class Mirai {
     const MiraiRadioGroupParser(),
     const MiraiSliderParser(),
     const MiraiOpacityParser(),
+    const MiraiPlaceholderParser(),
   ];
 
   static final _actionParsers = <MiraiActionParser>[

packages/mirai/lib/src/parsers/mirai_placeholder/mirai_placeholder.dart

@@ -0,0 +1,20 @@
+import 'package:freezed_annotation/freezed_annotation.dart';
+
+export 'package:mirai/src/parsers/mirai_placeholder/mirai_placeholder_parser.dart';
+
+part 'mirai_placeholder.freezed.dart';
+part 'mirai_placeholder.g.dart';
+
+@freezed
+class MiraiPlaceholder with _$MiraiPlaceholder {
+  const factory MiraiPlaceholder({
+    @Default(2.0) double fallbackWidth,
+    @Default(400.0) double fallbackHeight,
+    @Default(400.0) double strokeWidth,
+    @Default('#455A64') String color,
+    Map<String, dynamic>? child,
+  }) = _MiraiPlaceholder;
+
+  factory MiraiPlaceholder.fromJson(Map<String, dynamic> json) =>
+      _$MiraiPlaceholderFromJson(json);
+}