0
我正在尝试将粒子发射器切换为开或关。 我有一些Reactjs代码可以用canvas元素创建雨/雪粒子。 我想出了每一个想法来杀死动画仍然导致内存泄漏（在这种情况下，我认为它只是投射一个新的画布而不是内存中的原始动画）。 这里是Codepen.停止降雨
这里是页面代码：
class CanvasComponent extends React.Component {
componentDidMount() {
this.BtnOnOff();
}
constructor() {
super();
this.toggleState = this.toggleState.bind(this);
this.state = {
isActive : false
}
}
toggleState() {
this.setState({isActive:!this.state.isActive});
this.BtnOnOff();
//console.log(this.state.isActive);
}
snowMaker() {
// Ref canvas & get context
const canvas = document.getElementById('canvas');
const ctx = canvas.getContext('2d');
// Weather Types/////////////
var liteSnow = 13; //code 13 for snow light fluries.
var snow = 16; //code 13 for snow fluries.
var hevySnow = 41; //code 41 for Heavy snow.
var hevySnow2 = 43; //code 43 for Heavy snow.
var DRain = 9; //code 9 for drizzel
var HRain = 3; //code 3/4 for Thunderstorms/severe thunderstorms
var Code = 43; // Code will take in the current weather code.
// Resize canvas
let width = canvas.width = window.innerWidth;
let height = canvas.height = window.innerHeight;
// Variables
if (Code === 13) { /// Make it snow (light fluries)
var drops = [];
var dropColour = "rgba(255,255,255,1)";
var dropLengths = [3, 3, 3, 3, 3, 3, 3];
var dropSkews = [-2, -1, 0, 1, 2];
var maxDrops = 100;
var velocity = 8;
var flutter = 5;
}
else if (Code === 16){ /// Make it snow (fluries)
var drops = [];
var dropColour = "rgba(255,255,255,1)";
var dropLengths = [3, 3, 3, 3, 3, 3, 3];
var dropSkews = [-2, -1, 0, 1, 2];
var maxDrops = 500;
var velocity = 7;
var flutter = 5;
}
else if (Code === 41||Code === 43){ /// Make it Heavy snow
var drops = [];
var dropColour = "rgba(255,255,255,1)";
var dropLengths = [3, 2, 3, 2, 3, 2, 3];
var dropSkews = [-3, -1, 0, 1, 3];
var maxDrops = 800;
var velocity = .5;
var flutter = 8;
}
else if (Code === 9){ /// Make it rain
var drops = [];
var dropColour = "rgba(255,255,255,0.41)";
var dropLengths = [4, 5, 3, 6, 2, 3, 3];
var dropSkews = [0, 0.2, 0, 0, 0.1];
var maxDrops = 100;
var velocity =1;
var flutter = 1;
}
else if (Code === 3||Code === 4){ /// Make it ThunderStorms
var drops = [];
var dropColour = "rgba(255,255,255,0.5)";
var dropLengths = [10, 8, 8, 8, 7, 15, 9];
var dropSkews = [-0.2, -0.3, -0.2, -0.2, 0.1];
var maxDrops = 1000;
var velocity = .8;
var flutter = .1;
}
// Raindrop class
class Droplet {
constructor(x, y, length, skew) {
this.x = x;
this.y = y;
this.length = length;
this.skew = skew;
}
// Move method
move() {
// Increment x & y
this.y += this.length/velocity;
this.x += this.skew/flutter;
// Set limits
if (this.y > height) {
this.y = 0;
}
if (this.x > width || this.x < 0) {
this.y = 0;
this.x = Math.floor(Math.random() * width);
}
}
// Draw method
draw(ctx) {
ctx.beginPath();
ctx.moveTo(this.x, this.y);
ctx.lineTo(this.x + this.skew, this.y + this.length);
ctx.strokeStyle = dropColour;
ctx.stroke();
}
}
// Create drops and push to array
for (let i = 0; i < maxDrops; i++) {
let instance = new Droplet(
Math.floor(Math.random() * width),
Math.floor(Math.random() * height),
randVal(dropLengths),
randVal(dropSkews)
);
drops.push(instance);
}
// Animation loop
function loop() {
// Clear Canvas
ctx.clearRect(0, 0, width, height);
// Draw/Move drops
for (let drop of drops) {
drop.move();
drop.draw(ctx);
}
// Animation Frame
requestAnimationFrame(loop)
}
// Begin animation
loop();
// Resize canvas - responsive
window.addEventListener('resize', resize);
function resize() {
width = canvas.width = window.innerWidth;
height = canvas.height = window.innerHeight;
}
// Function for random array values
function randVal(array) {
return array[Math.floor(Math.random() * array.length)];
}
}////////End of update canvas
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
snowKiller() {
// Ref canvas & get context
const canvas = document.getElementById('canvas');
const ctx = canvas.getContext('2d');
var Code = 13;
// Resize canvas
let width = canvas.width = window.innerWidth;
let height = canvas.height = window.innerHeight;
// Variables
if (Code === 13) { /// Make it snow (light fluries)
var drops = [];
var dropColour = "";
var dropLengths = [0];
var dropSkews = [0];
var maxDrops = 0;
var velocity = 0;
var flutter = 0;
}
// Raindrop class
class Droplet {
constructor(x, y, length, skew) {
this.x = x;
this.y = y;
this.length = length;
this.skew = skew;
}
// Move method
move() {
// Increment x & y
this.y += this.length/velocity;
this.x += this.skew/flutter;
// Set limits
if (this.y > height) {
this.y = 0;
}
if (this.x > width || this.x < 0) {
this.y = 0;
this.x = Math.floor(Math.random() * width);
}
}
// Draw method
draw(ctx) {
ctx.beginPath();
ctx.moveTo(this.x, this.y);
ctx.lineTo(this.x + this.skew, this.y + this.length);
ctx.strokeStyle = dropColour;
ctx.stroke();
}
}
// Create drops and push to array
for (let i = 0; i < maxDrops; i++) {
let instance = new Droplet(
Math.floor(Math.random() * width),
Math.floor(Math.random() * height),
randVal(dropLengths),
randVal(dropSkews)
);
drops.push(instance);
}
// Animation loop
function loop() {
// Clear Canvas
ctx.clearRect(0, 0, width, height);
// Draw/Move drops
for (let drop of drops) {
drop.move();
drop.draw(ctx);
}
// Animation Frame
requestAnimationFrame(loop)
}
// Begin animation
loop();
// Resize canvas - responsive
window.addEventListener('resize', resize);
function resize() {
width = canvas.width = window.innerWidth;
height = canvas.height = window.innerHeight;
}
// Function for random array values
function randVal(array) {
return array[Math.floor(Math.random() * array.length)];
}
}////////End of update canvas
BtnOnOff(){
const OnOff =$('#Button').attr('class');
if(OnOff=== "active"){
// alert('this is on!')
this.snowMaker();
}else {
this.snowKiller();
// alert('this is off!');
}
console.log(OnOff);
}
render() {
return (
<div>
<button id="Button" className={this.state.isActive ? 'inactive' : 'active'} onClick ={this.toggleState}>{this.state.isActive ? 'STOP' : 'START'}</button>
<canvas id="canvas"/>
</div>
);
}
}
ReactDOM.render(<CanvasComponent/>, document.getElementById('app'));
Idealy的解决办法是像清除requestAnimationFrame，但我似乎无法推测出来。 帮助将非常令人失望。 感谢
https://www.youtube.com/watch?v=m7jibFQ5Tno，HTH –