ngIf 將元素list移至 ng-template

src/app/app.component.html

@@ -1,10 +1,13 @@
 <button type="button" (click)="onLoad()">載入資料</button>
 <button type="button" (click)="onClear()">清除資料</button>
 
-<div *ngIf="tasks.length >= 1; else empty">
-  <app-task *ngFor="let task of tasks; let odd = odd" [class.odd]="odd" [task]="task"></app-task>
-</div>
+<div *ngIf="tasks.length === 0; then empty else list"></div>
 
 <ng-template #empty>
   <div class="data-empty">無待辦事項</div>
 </ng-template>
+
+<ng-template #list>
+  <app-task *ngFor="let task of tasks; let odd=odd" [class.odd]="odd"
+  [task] = "task"></app-task>
+</ng-template>