极客教程Angular PrimeNG树的虚拟滚动
Angular PrimeNG是一个开源框架，拥有丰富的原生Angular UI组件，可用于出色的风格设计，这个框架可用于制作响应式网站，非常容易。这篇文章将向我们展示如何在Angular PrimeNG中使用树的虚拟滚动。
Angular PrimeNG Tree Virtual Scrolling是用来在Tree组件中启用虚拟滚动。VirtualScroller是一种有效处理数据的方法。
语法:
<p-tree [value]="..."
[virtualScroll]="true"
[virtualScrollItemSize]="...."
scrollHeight="...px">
</p-tree>
创建Angular应用程序和模块安装。
第1步：使用以下命令创建一个Angular应用程序。
ng new appname
第2步：创建你的项目文件夹即appname后，使用以下命令移动到它。
cd appname
步骤3：在你给定的目录中安装PrimeNG。
npm install primeng --save
npm install primeicons --save
项目结构：它将看起来像如下。
Project Structure
例子1：下面是一个简单的例子，演示Angular PrimeNG TreeTable虚拟滚动的使用。
<h2 style="color: green">GeeksforGeeks</h2>
<h4>Angular PrimeNG Tree Virtual Scrolling</h4>
<p-tree
[value]="files1"
[virtualScroll]="true"
[virtualScrollItemSize]="40"
scrollHeight="200px">
</p-tree>
import { Component, OnInit } from '@angular/core';
import { NodeService } from './nodeservice';
import { TreeNode } from 'primeng/api';
@Component({
selector: 'app-root',
templateUrl: './app.component.html',
})
export class AppComponent {
files1: TreeNode[] = [];
constructor(private nodeService: NodeService) { }
ngOnInit() {
this.files1 = [
{ label: 'Z', icon: 'pi pi-folder' },
{ label: 'A', icon: 'pi pi-folder' },
{ label: 'D', icon: 'pi pi-folder' },
{ label: 'C', icon: 'pi pi-folder' },
{ label: 'W', icon: 'pi pi-folder' },
{ label: 'E', icon: 'pi pi-folder' },
{ label: 'R', icon: 'pi pi-folder' },
{ label: 'G', icon: 'pi pi-folder' },
{ label: 'K', icon: 'pi pi-folder' },
{
label: 'A',
icon: 'pi pi-folder',
children: [
{
label: 'B',
icon: 'pi pi-folder',
children: [
{
label: 'C',
icon: 'pi pi-folder',
},
{
label: 'D',
icon: 'pi pi-folder',
},
],
},
{
label: 'E',
icon: 'pi pi-folder',
children: [
{
label: 'F',
icon: 'pi pi-folder',
},
],
},
],
},
{
label: 'G',
icon: 'pi pi-folder',
children: [
{
label: 'H',
icon: 'pi pi-folder',
},
{
label: 'I',
icon: 'pi pi-folder',
},
{
label: 'J',
icon: 'pi pi-folder',
},
],
},
];
}
}
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule } from '@angular/forms';
import { HttpClientModule } from '@angular/common/http';
import { BrowserAnimationsModule }
from '@angular/platform-browser/animations';
import { AppComponent } from './app.component';
import { NodeService } from './nodeservice';
import { TreeModule } from 'primeng/tree';
import { ButtonModule } from 'primeng/button';
import { InputTextModule } from 'primeng/inputtext';
import { VirtualScrollerModule }
from 'primeng/virtualscroller';
@NgModule({
imports: [
BrowserModule,
BrowserAnimationsModule,
TreeModule,
ButtonModule,
InputTextModule,
HttpClientModule,
FormsModule,
VirtualScrollerModule
],
declarations: [AppComponent],
bootstrap: [AppComponent],
providers: [NodeService],
})
export class AppModule { }
输出:
例子2：下面是另一个例子，演示了Angular PrimeNG TreeTable虚拟滚动的使用。
<h2 style="color: green">GeeksforGeeks</h2>
<h4>Angular PrimeNG Tree Virtual Scrolling</h4>
<p-tree
[value]="files1"
[virtualScroll]="true"
[virtualScrollItemSize]="40"
scrollHeight="200px">
</p-tree>
import { Component, OnInit } from '@angular/core';
import { NodeService } from './nodeservice';
import { TreeNode } from 'primeng/api';
@Component({
selector: 'app-root',
templateUrl: './app.component.html',
})
export class AppComponent {
files1: TreeNode[] = [];
constructor(private nodeService: NodeService) { }
ngOnInit() {
this.files1 = [
{
label: 'Z',
icon: 'pi pi-folder',
children: [
{
label: 'B',
icon: 'pi pi-folder',
children: [
{
label: 'C',
icon: 'pi pi-folder',
},
{
label: 'D',
icon: 'pi pi-folder',
},
],
},
],
},
{
label: 'A',
icon: 'pi pi-folder',
children: [
{
label: 'B',
icon: 'pi pi-folder',
children: [
{
label: 'C',
icon: 'pi pi-folder',
},
{
label: 'D',
icon: 'pi pi-folder',
},
],
},
],
},
{
label: 'D',
icon: 'pi pi-folder',
children: [
{
label: 'B',
icon: 'pi pi-folder',
children: [
{
label: 'C',
icon: 'pi pi-folder',
},
{
label: 'D',
icon: 'pi pi-folder',
},
],
},
],
},
{
label: 'C',
icon: 'pi pi-folder',
children: [
{
label: 'B',
icon: 'pi pi-folder',
children: [
{
label: 'C',
icon: 'pi pi-folder',
},
{
label: 'D',
icon: 'pi pi-folder',
},
],
},
],
},
{
label: 'W',
icon: 'pi pi-folder',
children: [
{
label: 'B',
icon: 'pi pi-folder',
children: [
{
label: 'C',
icon: 'pi pi-folder',
},
{
label: 'D',
icon: 'pi pi-folder',
},
],
},
],
},
{
label: 'E',
icon: 'pi pi-folder',
children: [
{
label: 'B',
icon: 'pi pi-folder',
children: [
{
label: 'C',
icon: 'pi pi-folder',
},
{
label: 'D',
icon: 'pi pi-folder',
},
],
},
],
},
{
label: 'R',
icon: 'pi pi-folder',
children: [
{
label: 'B',
icon: 'pi pi-folder',
children: [
{
label: 'C',
icon: 'pi pi-folder',
},
{
label: 'D',
icon: 'pi pi-folder',
},
],
},
],
},
{ label: 'G', icon: 'pi pi-folder' },
{ label: 'K', icon: 'pi pi-folder' },
{
label: 'A',
icon: 'pi pi-folder',
children: [
{
label: 'B',
icon: 'pi pi-folder',
children: [
{
label: 'C',
icon: 'pi pi-folder',
},
{
label: 'D',
icon: 'pi pi-folder',
},
],
},
{
label: 'E',
icon: 'pi pi-folder',
children: [
{
label: 'F',
icon: 'pi pi-folder',
},
],
},
],
},
{
label: 'G',
icon: 'pi pi-folder',
children: [
{
label: 'H',
icon: 'pi pi-folder',
},
{
label: 'I',
icon: 'pi pi-folder',
},
{
label: 'J',
icon: 'pi pi-folder',
},
],
},
];
}
}
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule } from '@angular/forms';
import { HttpClientModule } from '@angular/common/http';
import { BrowserAnimationsModule }
from '@angular/platform-browser/animations';
import { AppComponent } from './app.component';
import { NodeService } from './nodeservice';
import { TreeModule } from 'primeng/tree';
import { ButtonModule } from 'primeng/button';
import { InputTextModule } from 'primeng/inputtext';
import { VirtualScroller, VirtualScrollerModule }
from 'primeng/virtualscroller';
@NgModule({
imports: [
BrowserModule,
BrowserAnimationsModule,
TreeModule,
ButtonModule,
InputTextModule,
HttpClientModule,
FormsModule,
VirtualScrollerModule
],
declarations: [AppComponent],
bootstrap: [AppComponent],
providers: [NodeService],
})
export class AppModule { }
输出:
