Adding a debounce.

This commit is contained in:
Dessalines 2019-08-03 13:26:20 -07:00
parent caf0af3539
commit 5a1e8aa645
2 changed files with 45 additions and 4 deletions

View file

@ -4,7 +4,7 @@ import { Subscription } from "rxjs";
import { retryWhen, delay, take } from 'rxjs/operators';
import { PostForm as PostFormI, Post, PostResponse, UserOperation, Community, ListCommunitiesResponse, ListCommunitiesForm, SortType, SearchForm, SearchType, SearchResponse } from '../interfaces';
import { WebSocketService, UserService } from '../services';
import { msgOp, getPageTitle } from '../utils';
import { msgOp, getPageTitle, debounce } from '../utils';
import * as autosize from 'autosize';
interface PostFormProps {
@ -87,7 +87,7 @@ export class PostForm extends Component<PostFormProps, PostFormState> {
<div class="form-group row">
<label class="col-sm-2 col-form-label">URL</label>
<div class="col-sm-10">
<input type="url" class="form-control" value={this.state.postForm.url} onInput={linkEvent(this, this.handlePostUrlChange)} />
<input type="url" class="form-control" value={this.state.postForm.url} onInput={linkEvent(this, debounce(this.handlePostUrlChange))} />
{this.state.suggestedTitle &&
<div class="mt-1 text-muted small font-weight-bold pointer" onClick={linkEvent(this, this.copySuggestedTitle)}>copy suggested title: {this.state.suggestedTitle}</div>
}
@ -96,7 +96,7 @@ export class PostForm extends Component<PostFormProps, PostFormState> {
<div class="form-group row">
<label class="col-sm-2 col-form-label">Title</label>
<div class="col-sm-10">
<textarea value={this.state.postForm.name} onInput={linkEvent(this, this.handlePostNameChange)} class="form-control" required rows={2} minLength={3} maxLength={100} />
<textarea value={this.state.postForm.name} onInput={linkEvent(this, debounce(this.handlePostNameChange))} class="form-control" required rows={2} minLength={3} maxLength={100} />
{this.state.suggestedPosts.length > 0 &&
<>
<div class="my-1 text-muted small font-weight-bold">These posts might be related</div>
@ -166,7 +166,6 @@ export class PostForm extends Component<PostFormProps, PostFormState> {
handlePostNameChange(i: PostForm, event: any) {
i.state.postForm.name = event.target.value;
let form: SearchForm = {
q: i.state.postForm.name,
type_: SearchType[SearchType.Posts],

View file

@ -117,3 +117,45 @@ export async function getPageTitle(url: string) {
return data;
}
export function debounce(func: any, wait: number = 500, immediate: boolean = false) {
// 'private' variable for instance
// The returned function will be able to reference this due to closure.
// Each call to the returned function will share this common timer.
let timeout: number;
// Calling debounce returns a new anonymous function
return function() {
// reference the context and args for the setTimeout function
var context = this,
args = arguments;
// Should the function be called now? If immediate is true
// and not already in a timeout then the answer is: Yes
var callNow = immediate && !timeout;
// This is the basic debounce behaviour where you can call this
// function several times, but it will only execute once
// [before or after imposing a delay].
// Each time the returned function is called, the timer starts over.
clearTimeout(timeout);
// Set the new timeout
timeout = setTimeout(function() {
// Inside the timeout function, clear the timeout variable
// which will let the next execution run when in 'immediate' mode
timeout = null;
// Check if the function already ran with the immediate flag
if (!immediate) {
// Call the original function with apply
// apply lets you define the 'this' object as well as the arguments
// (both captured before setTimeout)
func.apply(context, args);
}
}, wait);
// Immediate mode and no wait timer? Execute the function..
if (callNow) func.apply(context, args);
}
}