diff --git a/src/core/system/index.ts b/src/core/system/index.ts
new file mode 100644
index 0000000..5ecdd1f
--- /dev/null
+++ b/src/core/system/index.ts
@@ -0,0 +1 @@
+export * from './ui';
diff --git a/src/core/system/ui/controller.ts b/src/core/system/ui/controller.ts
new file mode 100644
index 0000000..3b690ea
--- /dev/null
+++ b/src/core/system/ui/controller.ts
@@ -0,0 +1,55 @@
+import { Component, VNodeProps } from 'vue';
+
+export interface IUIControllerConfig<Element, UI> {
+    /**
+     * 将一个ui挂载至目标元素时的操作
+     * @param element 要挂载至的目标元素
+     * @param ui 要挂载的ui对象
+     */
+    insert(element: Element, ui: UI): void;
+
+    /**
+     * 将一个ui从目标元素上移除时的操作
+     * @param element 被移除ui的父元素
+     * @param ui 要被移除的ui元素
+     */
+    remove(element: Element, ui: UI): void;
+
+    /**
+     * 创建一个新UI
+     * @param component UI组件
+     * @param props UI传递的props
+     */
+    createUI(
+        component: Component,
+        props?: (VNodeProps & { [key: string]: any }) | null
+    ): UI;
+}
+
+export const enum OpenOption {
+    Push,
+    Unshift
+}
+
+export const enum CloseOption {
+    Splice,
+    Pop,
+    Shift
+}
+
+export class UIController<Element, UI> {
+    constructor(config: IUIControllerConfig<Element, UI>) {}
+
+    /**
+     * 设置当ui改变时控制器的行为
+     * @param open 打开时的行为
+     * @param close 关闭时的行为
+     */
+    setChangeMode(open: OpenOption, close: CloseOption) {}
+
+    /**
+     * 将这个UI控制器挂载至容器上
+     * @param container 要挂载至的容器
+     */
+    mount(container: Element) {}
+}
diff --git a/src/core/system/ui/index.ts b/src/core/system/ui/index.ts
new file mode 100644
index 0000000..0471403
--- /dev/null
+++ b/src/core/system/ui/index.ts
@@ -0,0 +1 @@
+export * from './controller';
diff --git a/src/plugin/utils.ts b/src/plugin/utils.ts
index 7b1b38a..65a60dc 100644
--- a/src/plugin/utils.ts
+++ b/src/plugin/utils.ts
@@ -517,3 +517,11 @@ export function calStringSize(str: string) {
 
     return size;
 }
+
+export function clamp(num: number, start: number, end: number) {
+    const s = Math.min(start, end);
+    const e = Math.max(start, end);
+    if (num < s) return s;
+    else if (num > e) return e;
+    return num;
+}