Convert accept type to the new one (#432)

src/Components/UploadImage.tsx

@@ -478,8 +478,20 @@ class UploadImage extends Component<UploadImageProps, UploadImageState> {
     render(): JSX.Element {
         const { disabled, icon, removeIconFunc, error, crop, onChange } = this.props;
         const maxSize = this.props.maxSize || 10 * 1024;
-        const accept = this.props.accept || { 'image/*': [] };
+        let accept = this.props.accept || { 'image/*': [] };
         const { uploadFile, anchorEl, cropHandler } = this.state;
+
+        // covert '"image/png"' to { 'image/*': [] }
+        if (typeof accept === 'string') {
+            accept = { [accept]: [] };
+        } else if (Array.isArray(accept)) {
+            const result: Record<string, string[]> = {};
+            accept.forEach(item => {
+                result[item] = [];
+            });
+            accept = result;
+        }
+
         return (
             <Dropzone
                 disabled={!!disabled || cropHandler}