core-egret.DisplayObjectContainer

egret.DisplayObjectContainer 多型操作範例

class Main extends eui.UILayer {

    protected createChildren(): void {
        super.createChildren();
        egret.lifecycle.onPause = () => egret.ticker.pause();
        egret.lifecycle.onResume = () => egret.ticker.resume();
        egret.registerImplementation('eui.IAssetAdapter', new AssetAdapter());
        egret.registerImplementation('eui.IThemeAdapter', new ThemeAdapter());
        this.runGame();
    }

    private async loadResource() {
        let loadingView = this.stage.addChild(new LoadingUI()) as LoadingUI;
        await RES.loadConfig('resource/default.res.json', 'resource/');
        await new Promise(resolve => new eui.Theme('resource/default.thm.json', this.stage).once(eui.UIEvent.COMPLETE, resolve, this));
        await RES.loadGroup('preload', 0, loadingView);
        this.stage.removeChild(loadingView);
    }

    private async runGame() {
        await this.loadResource();
        // --- Edwin 給你最乾淨的程式碼, 從這行以下開始寫喔 ---

        // 添加自定義顯示清單物件, 也可用子類 eui.Group 取代(如果容器內都放 eui 組件的話)
        const doc = new egret.DisplayObjectContainer();
        this.addChild(doc);

        // 利用多型特性, 父類之宣告參數可以設置子類
        doc.addChild(new eui.Label('LabelA'));
        doc.addChild(new eui.Image('egret_icon_png'));
        doc.addChild(new eui.Label('LabelB'));
        doc.addChild(new eui.Image('egret_icon_png'));
        doc.addChild(new eui.Label('LabelC'));
        doc.addChild(new eui.Image('egret_icon_png'));

        // len 做變數存起來, 因為不知道底層運算是否用 for loop 計算個數, 如果用 i < doc.numChildren 可能會耗效能
        for (let i = 0, len = doc.numChildren; i < len; i++) {
            //利用多型特性, 只有設置其 x,y 屬性, 不用刻意轉型為原本型態如 eui.Label 或 eui.Image
            const mydo: egret.DisplayObject = doc.getChildAt(i);
            mydo.x = 0;
            mydo.y = 180 * i;
        }
    }

}