diff --git a/$index.ts b/$index.ts
index 0d972c1..844621b 100644
--- a/$index.ts
+++ b/$index.ts
@@ -1,4 +1,4 @@
-import { $State, $StateArgument, $StateOption } from "./index";
+import { $EventManager, $State, $StateArgument, $StateOption } from "./index";
 import { $Node } from "./lib/node/$Node"
 import { $Document } from "./lib/node/$Document"
 import { $Anchor } from "./lib/node/$Anchor";
@@ -11,7 +11,6 @@ import { $Label } from "./lib/node/$Label";
 import { $Image } from "./lib/node/$Image";
 import { $Canvas } from "./lib/node/$Canvas";
 import { $Dialog } from "./lib/node/$Dialog";
-import { $View } from "./lib/node/$View";
 import { $Select } from "./lib/node/$Select";
 import { $Option } from "./lib/node/$Option";
 import { $OptGroup } from "./lib/node/$OptGroup";
@@ -56,8 +55,9 @@ export function $(resolver: any) {
 }
 export namespace $ {
     export let anchorHandler: null | (($a: $Anchor, e: Event) => void) = null;
-    export let anchorPreventDefault: boolean = false;
     export const TagNameElementMap = {
+        'html': $Container,
+        'head': $Container,
         'document': $Document,
         'body': $Container,
         'a': $Anchor,
@@ -84,7 +84,6 @@ export namespace $ {
         'img': $Image,
         'dialog': $Dialog,
         'canvas': $Canvas,
-        'view': $View,
         'select': $Select,
         'option': $Option,
         'optgroup': $OptGroup,
@@ -192,9 +191,7 @@ export namespace $ {
         })
     }
 
-    export function rem(amount: number = 1) {
-        return parseInt(getComputedStyle(document.documentElement).fontSize) * amount
-    }
+    export function rem(amount: number = 1) { return parseInt(getComputedStyle(document.documentElement).fontSize) * amount }
 
     export function html(html: string) {
         const body = new DOMParser().parseFromString(html, 'text/html').body;
@@ -240,6 +237,10 @@ export namespace $ {
         Object.assign($.TagNameElementMap, {[string]: node});
         return $.TagNameElementMap;
     }
+
+    export function events<N extends string>(...eventname: N[]) { return new $EventManager<{[keys in N]: any[]}>().register(...eventname) }
+
+    export function call<T>(fn: () => T): T { return fn() }
 }
 type BuildNodeFunction = (...args: any[]) => $Node;
 type BuilderSelfFunction<K extends $Node> = (self: K) => void;
diff --git a/index.ts b/index.ts
index ddc9752..6ff3bea 100644
--- a/index.ts
+++ b/index.ts
@@ -1,7 +1,7 @@
 declare global {
     var $: import('./$index').$;
     interface Array<T> {
-        detype<F extends undefined | null, O>(...types: F[]): Array<Exclude<T, F>>
+        detype<F extends any, O>(...types: F[]): Array<Exclude<T, F | undefined | void>>
     }
     type OrMatrix<T> = T | OrMatrix<T>[];
     type OrArray<T> = T | T[];
@@ -23,11 +23,11 @@ declare global {
         $: import('./lib/node/$Node').$Node;
     }
 }
-Array.prototype.detype = function <T extends undefined | null, O>(this: O[], ...types: T[]) {
+Array.prototype.detype = function <T extends any, O>(this: O[], ...types: T[]) {
     return this.filter(item => {
         if (!types.length) return item !== undefined;
         else for (const type of types) if (typeof item !== typeof type) return true;  else return false;
-    }) as Exclude<O, T>[];
+    }) as Exclude<O, T | undefined | void>[];
 }
 export * from "./$index";
 export * from "./lib/node/$Node";
@@ -40,7 +40,6 @@ export * from "./lib/node/$Button";
 export * from "./lib/node/$Form";
 export * from "./lib/$EventManager";
 export * from "./lib/$State";
-export * from "./lib/node/$View";
 export * from "./lib/node/$Select";
 export * from "./lib/node/$Option";
 export * from "./lib/node/$OptGroup";
diff --git a/lib/$EventManager.ts b/lib/$EventManager.ts
index 35cc005..df54dcb 100644
--- a/lib/$EventManager.ts
+++ b/lib/$EventManager.ts
@@ -8,7 +8,7 @@ export abstract class $EventMethod<EM> {
     once<K extends keyof EM>(type: K, callback: (...args: EM[K]) => any) { this.events.once(type, callback); return this }
 }
 export class $EventManager<EM> {
-    private eventMap = new Map<string, $Event>();
+    eventMap = new Map<string, $Event>();
     register(...names: string[]) { 
         names.forEach(name => {
             const event = new $Event(name);
diff --git a/lib/node/$Anchor.ts b/lib/node/$Anchor.ts
index 87bf5fe..9160bef 100644
--- a/lib/node/$Anchor.ts
+++ b/lib/node/$Anchor.ts
@@ -7,8 +7,10 @@ export class $Anchor extends $Container<HTMLAnchorElement> {
         super('a', options);
         // Link Handler event
         this.dom.addEventListener('click', e => {
-            if ($.anchorPreventDefault) e.preventDefault();
-            if ($.anchorHandler && !!this.href()) $.anchorHandler(this, e)
+            if ($.anchorHandler && !!this.href()) {
+                e.preventDefault();
+                $.anchorHandler(this, e);
+            }
         })
     }
     /**Set URL of anchor element. */
diff --git a/lib/node/$Async.ts b/lib/node/$Async.ts
index 5ef5358..c39c9d1 100644
--- a/lib/node/$Async.ts
+++ b/lib/node/$Async.ts
@@ -1,5 +1,7 @@
-import { $Container, $ContainerOptions } from "./$Container";
+import { $State } from "../$State";
+import { $Container, $ContainerContentType, $ContainerOptions } from "./$Container";
 import { $Node } from "./$Node";
+import { $Text } from "./$Text";
 export interface $AsyncNodeOptions extends $ContainerOptions {}
 export class $Async<N extends $Node = $Node> extends $Container {
     #loaded: boolean = false;
@@ -7,14 +9,22 @@ export class $Async<N extends $Node = $Node> extends $Container {
         super('async', options)
     }
 
-    await<T extends $Node = $Node>($node: Promise<T>) {
-        $node.then($node => this._loaded($node));
+    await<T extends $Node>($node: Promise<T | $ContainerContentType> | (($self: this) => Promise<T | $ContainerContentType>)) {
+        if ($node instanceof Function) $node(this).then($node => this._loaded($node));
+        else $node.then($node => this._loaded($node));
         return this as $Async<T>
     }
 
-    protected _loaded($node: $Node) {
+    protected _loaded($node: $ContainerContentType) {
         this.#loaded = true;
-        this.replace($node)
+        if (typeof $node === 'string') this.replace(new $Text($node));
+        else if ($node instanceof $State) {
+            const ele = new $Text($node.toString());
+            $node.use(ele, 'content');
+            this.replace(ele);
+        } 
+        else if ($node === null || $node === undefined) this.replace(new $Text(String($node)));
+        else this.replace($node)
         this.dom.dispatchEvent(new Event('load'))
     }
 
diff --git a/lib/node/$Container.ts b/lib/node/$Container.ts
index ac4ba9b..f8cb1bc 100644
--- a/lib/node/$Container.ts
+++ b/lib/node/$Container.ts
@@ -22,22 +22,29 @@ export class $Container<H extends HTMLElement = HTMLElement> extends $HTMLElemen
 
     private __position_cursor = 0;
     /**Insert element to this element */
-    insert(children: $ContainerContentBuilder<this>, position = -1): this { return $.fluent(this, arguments, () => this, () => {
-        if (children instanceof Function) children = children(this);
+    insert(children: $ContainerContentBuilder<this>, position = -1): this { return $.fluent(this, arguments, () => this, async () => {
+        if (children instanceof Function) children = await children(this); // resolve function
         children = $.orArrayResolve(children);
+        // Set position cursor depend negative or positive number, position will count from last index when position is negative.
         this.__position_cursor = position < 0 ? this.children.array.length + position : position;
         for (const child of children) {
-            if (child === undefined || child === null) continue;
-            if (child instanceof Array) this.insert(child, this.__position_cursor);
-            else if (typeof child === 'string') this.children.add(new $Text(child), position);
+            if (child === undefined || child === null) continue; // skip
+            if (child instanceof Array) this.insert(child, this.__position_cursor); // insert element group at this position
+            else if (typeof child === 'string') this.children.add(new $Text(child), position); // turn string into $Text element
             else if (child instanceof $State) {
-                const ele = new $Text(child.toString());
-                child.use(ele, 'content');
+                const ele = new $Text(child.toString()); // turn $State object into $Text element
+                child.use(ele, 'content'); // bind $Text elelment and function name to $State
                 this.children.add(ele, position);
-            } else this.children.add(child, position);
-            this.__position_cursor += 1;
+            } 
+            else if (child instanceof Promise) {
+                const $Async = (await import('./$Async')).$Async; // import $Async avoid extends error
+                const ele = new $Async().await(child) // using $Async.await resolve promise element
+                this.children.add(ele, position); // insert $Async element at this position, leave a position for promised element
+            }
+            else this.children.add(child, position); // insert $Node element directly
+            this.__position_cursor += 1; // increase position count
         }
-        this.children.render();
+        this.children.render(); // start to render dom tree
     })}
 
     /**Remove all children elemetn from this element */
@@ -64,5 +71,6 @@ export class $Container<H extends HTMLElement = HTMLElement> extends $HTMLElemen
     scrollLeft(scrollLeft?: $StateArgument<number> | undefined) { return $.fluent(this, arguments, () => this.dom.scrollLeft, () => $.set(this.dom, 'scrollLeft', scrollLeft as any))}
 }
 
-export type $ContainerContentBuilder<P extends $Container> = OrMatrix<$ContainerContentType> | (($node: P) => OrMatrix<$ContainerContentType>)
+export type $ContainerContentBuilder<P extends $Container> = $ContainerContentGroup | (($node: P) => OrPromise<$ContainerContentGroup>)
+export type $ContainerContentGroup = OrMatrix<OrPromise<$ContainerContentType>>
 export type $ContainerContentType = $Node | string | undefined | $State<any> | null
\ No newline at end of file
diff --git a/lib/node/$Element.ts b/lib/node/$Element.ts
index 6026ef6..9045482 100644
--- a/lib/node/$Element.ts
+++ b/lib/node/$Element.ts
@@ -4,6 +4,7 @@ export interface $ElementOptions {
     id?: string;
     class?: string[];
     dom?: HTMLElement | SVGElement;
+    tagname?: string;
 }
 
 export class $Element<H extends HTMLElement | SVGElement = HTMLElement> extends $Node<H> {
@@ -19,7 +20,7 @@ export class $Element<H extends HTMLElement | SVGElement = HTMLElement> extends
     private createDom(tagname: string, options?: $ElementOptions) {
         if (options?.dom) return options.dom;
         if (tagname === 'svg') return document.createElementNS("http://www.w3.org/2000/svg", "svg");
-        return document.createElement(tagname);
+        return document.createElement(options?.tagname ?? tagname);
 
     }
 
@@ -85,8 +86,8 @@ export class $Element<H extends HTMLElement | SVGElement = HTMLElement> extends
 
     animate(keyframes: Keyframe[] | PropertyIndexedKeyframes | null, options?: number | KeyframeAnimationOptions, callback?: (animation: Animation) => void) {
         const animation = this.dom.animate(keyframes, options);
-        if (callback) callback(animation);
-        return this;
+        if (callback) animation.onfinish = () => callback(animation);
+        return animation;
     }
 
     getAnimations(options?: GetAnimationsOptions) { return this.dom.getAnimations(options) }
diff --git a/lib/node/$Input.ts b/lib/node/$Input.ts
index ae11610..73aeb86 100644
--- a/lib/node/$Input.ts
+++ b/lib/node/$Input.ts
@@ -1,10 +1,10 @@
-import { $Element, $ElementOptions } from "./$Element";
 import { $State, $StateArgument } from "../$State";
 import { $HTMLElementAPIFilter, $HTMLElementAPIs } from "../$ElementTemplate";
 import { $Util } from "../$Util";
+import { $HTMLElement, $HTMLElementOptions } from "./$HTMLElement";
 
-export interface $InputOptions extends $ElementOptions {}
-export class $Input<T extends string | number = string> extends $Element<HTMLInputElement> {
+export interface $InputOptions extends $HTMLElementOptions {}
+export class $Input<T extends string | number = string> extends $HTMLElement<HTMLInputElement> {
     constructor(options?: $InputOptions) {
         super('input', options);
     }
@@ -117,7 +117,6 @@ export class $Input<T extends string | number = string> extends $Element<HTMLInp
 
 export interface $Input extends $HTMLElementAPIFilter<$Input, 'checkValidity' | 'reportValidity' | 'autocomplete' | 'name' | 'form' | 'required' | 'validationMessage' | 'validity' | 'willValidate' | 'formAction' | 'formEnctype' | 'formMethod' | 'formNoValidate' | 'formTarget'> {}
 $Util.mixin($Input, $HTMLElementAPIs.create('checkValidity', 'reportValidity', 'autocomplete', 'name', 'form', 'required', 'validationMessage', 'validity', 'willValidate', 'formAction', 'formEnctype', 'formMethod', 'formNoValidate', 'formTarget'))
-
 export class $NumberInput extends $Input<number> {
     constructor(options?: $InputOptions) {
         super(options)
@@ -169,7 +168,7 @@ export class $FileInput extends $Input<string> {
     }
 
     static from($input: $Input) {
-        return $.mixin($Input, this) as $CheckInput;
+        return $.mixin($Input, this) as $FileInput;
     }
     
     multiple(): boolean;
@@ -181,4 +180,5 @@ export class $FileInput extends $Input<string> {
     accept(...filetype: string[]) { return $.fluent(this, arguments, () => this.dom.accept.split(','), () => this.dom.accept = filetype.toString() )}
 }
 
-export type $InputType<T extends InputType> = T extends 'number' ? $NumberInput : T extends 'radio' | 'checkbox' ? $CheckInput : T extends 'file' ? $FileInput : $Input<string>;
\ No newline at end of file
+export type $InputType<T extends InputType> = T extends 'number' ? $NumberInput : T extends 'radio' | 'checkbox' ? $CheckInput : T extends 'file' ? $FileInput : $Input<string>;
+$Util.mixin($Input, [$NumberInput, $CheckInput, $FileInput])
\ No newline at end of file
diff --git a/lib/node/$Node.ts b/lib/node/$Node.ts
index 7591440..b9968ca 100644
--- a/lib/node/$Node.ts
+++ b/lib/node/$Node.ts
@@ -65,4 +65,8 @@ export abstract class $Node<N extends Node = Node> {
         if (this instanceof $Element) return true;
         else return false;
     }
+    get element(): $Element | null { 
+        if (this instanceof $Element) return this;
+        else return null;
+    }
 }
\ No newline at end of file
diff --git a/lib/node/$Select.ts b/lib/node/$Select.ts
index 0d2b442..dcafc8e 100644
--- a/lib/node/$Select.ts
+++ b/lib/node/$Select.ts
@@ -1,7 +1,7 @@
 import { $Container, $ContainerOptions } from "./$Container";
 import { $OptGroup } from "./$OptGroup";
 import { $Option } from "./$Option";
-import { $StateArgument } from "../$State";
+import { $State, $StateArgument } from "../$State";
 import { $HTMLElementAPIFilter, $HTMLElementAPIs } from "../$ElementTemplate";
 import { $Util } from "../$Util";
 
@@ -31,7 +31,13 @@ export class $Select extends $Container<HTMLSelectElement> {
     
     value(): string;
     value(value?: $StateArgument<string> | undefined): this;
-    value(value?: $StateArgument<string> | undefined) { return $.fluent(this, arguments, () => this.dom.value, () => $.set(this.dom, 'value', value))}
+    value(value?: $StateArgument<string> | undefined) { return $.fluent(this, arguments, () => this.dom.value, () => $.set(this.dom, 'value', value as $State<string> | string, (value$) => {
+        this.on('input', () => {
+            if (value$.attributes.has(this.dom) === false) return;
+            if (typeof value$.value === 'string') (value$ as $State<string>).set(`${this.value()}`)
+            if (typeof value$.value === 'number') (value$ as unknown as $State<number>).set(Number(this.value()))
+        })
+    }))}
 
     get labels() { return Array.from(this.dom.labels ?? []).map(label => $(label)) }
 }
diff --git a/lib/node/$View.ts b/lib/node/$View.ts
deleted file mode 100644
index 75ae1d6..0000000
--- a/lib/node/$View.ts
+++ /dev/null
@@ -1,41 +0,0 @@
-import { $Container, $ContainerOptions } from "./$Container";
-import { $EventManager } from "../$EventManager";
-import { $Node } from "./$Node";
-
-export interface $ViewOptions extends $ContainerOptions {}
-export class $View extends $Container {
-    protected view_cache = new Map<string, $Node>();
-    event = new $EventManager<$ViewEventMap>().register('switch')
-    content_id: string | null = null;
-    constructor(options?: $ViewOptions) {
-        super('view', options);
-    }
-
-    setView(id: string, $node: $Node) {
-        this.view_cache.set(id, $node);
-        return this;
-    }
-
-    deleteView(id: string) {
-        this.view_cache.delete(id);
-        return this;
-    }
-
-    deleteAllView() {
-        this.view_cache.clear();
-        return this;
-    }
-
-    switchView(id: string) {
-        const target_content = this.view_cache.get(id);
-        if (target_content === undefined) return this;
-        this.content(target_content);
-        this.content_id = id;
-        this.event.fire('switch', id);
-        return this;
-    }
-}
-
-export interface $ViewEventMap {
-    'switch': [id: string]
-}
\ No newline at end of file
diff --git a/package.json b/package.json
index 7f68cda..55207f9 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "elexis",
   "description": "Build Web in Native JavaScript Syntax",
-  "version": "0.2.4",
+  "version": "0.2.5",
   "author": {
     "name": "defaultkavy",
     "email": "defaultkavy@gmail.com",