更改 SegmentedBar 组件的索引时,我在更新 UI 时遇到问题。
我开始尝试将分段栏与 angular/nativescript 路由器导航一起使用。我可以让 SegmentedBar 更新栏的索引,然后触发导航更改,但视图没有使用来自组件的动态数据更新任何 UI。
所以我稍微简化了一点,让所有的 UI 都呈现在 app.component 中,包括 SegmentedBar。但同样的问题,我正在检查 SegmentedBar 上的更改,然后更新变量,但它不反映 UI 中的更改。
这是组件的错误还是我做错了什么?
import {Component, AfterViewInit, OnInit, ViewChild, ElementRef} from "@angular/core";
import {TabsComponent} from "./components/tabs/tabs.component";
import {HTTP_PROVIDERS, Http} from '@angular/http';
import {ROUTER_DIRECTIVES, Router} from '@angular/router';
import {NS_ROUTER_DIRECTIVES} from 'nativescript-angular/router';
import {SegmentedBar, SegmentedBarItem, SelectedIndexChangedEventData} from 'ui/segmented-bar';
@Component({
selector: 'my-app',
//directives: [ROUTER_DIRECTIVES, NS_ROUTER_DIRECTIVES, TabsComponent],
//providers: [HTTP_PROVIDERS, TodoService],
template: `
<ActionBar title="Calculator" class="ui-action-bar">
<ActionItem tap="onShare"
ios.systemIcon="9" ios.position="right"
android.systemIcon="ic_menu_share" android.position="actionBar"></ActionItem>
</ActionBar>
<StackLayout>
<StackLayout class="ui-nav">
<SegmentedBar #tabs [items]="items" [selectedIndex]="selectedIndex"></SegmentedBar>
</StackLayout>
<StackLayout class="o-section o-section--edge-padding" orientation="vertical" visibility="{{ selectedIndex == 1 ? 'visible' : 'collapse' }}">
<Label text="Home" class="ui-dia-section__title"></Label>
<Label [text]="selectedIndex" class="ui-dia-section__title"></Label>
<Label text="{{selectedIndex}}" class="ui-dia-section__title"></Label>
</StackLayout>
<StackLayout class="o-section o-section--edge-padding" orientation="vertical" visibility="{{ selectedIndex == 0 ? 'visible' : 'collapse' }}">
<Label text="Glossary" class="ui-dia-section__title"></Label>
<Label [text]="selectedIndex" class="ui-dia-section__title"></Label>
</StackLayout>
</StackLayout>
`})
export class AppComponent {
selectedIndex: number;
items: Array<any>;
showHomeScreen: boolean = true;
showGlossaryScreen: boolean = false;
@ViewChild("tabs") tabs: ElementRef;
constructor() {
this.selectedIndex = 0;
this.items = [{ title: 'Calculator' }, { title: 'Glossary' }];
}
ngAfterViewInit() {
this.tabs.nativeElement.on(SegmentedBar.selectedIndexChangedEvent, (args: SelectedIndexChangedEventData) => {
switch (args.newIndex) {
case 0:
console.log('first selected, selectedIndex: ' + this.selectedIndex);
//this.router.navigateByUrl("home");
this.selectedIndex = 0;
break;
case 1:
console.log('second selected, selectedIndex: ' + this.selectedIndex);
// this.router.navigateByUrl("glossary");
this.selectedIndex = 1;
break;
case 3:
console.log('third selected')
break;
}
})
}
ngOnInit(){
console.log('ngOnInit, index: ' + this.selectedIndex);
}
}