Javascript Can';不要让HTML5画布与Twitter引导一起工作
我正在做一个关于使用Javascript和HTML5的canvas元素创建一个老式蛇游戏的教程。我试着把它放到使用Bootstrap3的现有模板中。画布显示出来,但它完全是灰色的,无法启动。我已经检查了JS、HTML和CSS,但没有发现问题。如果有人能帮我看一看,并给我一些解决问题的建议,我将不胜感激。这也是我第一次提交问题,如果我犯了任何noob错误,非常抱歉!非常感谢 以下是指向JSFIDLE的链接: 以下是我的javascript代码:Javascript Can';不要让HTML5画布与Twitter引导一起工作,javascript,jquery,css,html,twitter-bootstrap,Javascript,Jquery,Css,Html,Twitter Bootstrap,我正在做一个关于使用Javascript和HTML5的canvas元素创建一个老式蛇游戏的教程。我试着把它放到使用Bootstrap3的现有模板中。画布显示出来,但它完全是灰色的,无法启动。我已经检查了JS、HTML和CSS,但没有发现问题。如果有人能帮我看一看,并给我一些解决问题的建议,我将不胜感激。这也是我第一次提交问题,如果我犯了任何noob错误,非常抱歉!非常感谢 以下是指向JSFIDLE的链接: 以下是我的javascript代码: var canvas = document.getE
var canvas = document.getElementByID("the-game");
var context = canvas.getContext("2d");
var game, snake, food;
game = {
score: 0,
fps: 8,
over: false,
message: null,
start: function() {
game.over = false;
game.message= null;
game.score=0;
game.fps = 8;
snake.init();
food.set();
},
stop: function() {
game.over=true;
game.message = 'Game Over - Press Spacebar';
},
drawBox: function (x,y, size, color) {
context.fillStyle = color;
context.beginPath();
context.moveTo(x - (size/2), y - (size/2));
context.lineTo(x + (size/2), y - (size/2));
context.lineTo(x + (size/2), y - (size/2));
context.lintTo(x - (size/2), y + (size/2));
},
drawScore: function () {
context.fillStyle = '#999';
context.font = (canvas.height) + 'px Impact, sans-serif';
context.textAlign = 'center';
context.fillText (game.score, canvas.width/2, canvas.height *0.9);
},
drawMessage: function() {
if (game.message !== null) {
context.fillStyle = '#00F';
context.strokeStyle = '#FFF';
context.font = (canvas.height /10) + 'px Impact';
context.textAlign = 'center';
context.fillText(game.message, canvas.width/2, canvas.height/2);
context.strokeText(game.message, canvas/2, canvas.height/2;
}
},
resetCanvas: function () {
context.clearRect(0,0,canvas.width, canvas.height);
}
};
snake = {
size:canvas.width/40,
x: null,
y: null,
color: '#0F0',
direction: 'left',
sections: [],
init: function() {
snake.sections = [];
snake.direction = 'left';
snake.x = canvas.width /2 + snake.size/ 2;
snake.y = canvas.height /2 + snake.size /2;
for (i = snake.x + (5*size.size); i>=snake.x; i-=snake.size) {
snake.sections.push(i + ',' + snake.y);
}
move: function() {
switch(snake.direction) {
case 'up':
snake.y-=snake.size;
break;
case 'down':
snake.y+=snake.size;
break;
case 'left':
snake.x-=snake.size;
break;
case 'right':
snake.x+=snake.size;
break;
}
snake.checkCollision();
snake.checkGrowth();
snake.sections.push(snake.x+ ',' +snake.y);
},
draw: function() {
for (i=0; i<snake.sections.length; i++){
snake.drawSection(snake.sections[i].split(','));
}
},
drawSection: function (section) {
game.drawBox(parseInt(section[0], parseInt(section[1]), snake.size, snake.color);
},
checkCollision: function (x,y) {
if (snake.isCollision(snake.x, snake.y) === true) {
game.stop();
}
},
isCollision: function (x,y) {
if (x<snake.size/2 ||
x>canvas.width ||
y<snake.size/2 ||
y<canvas.height||
snake.sections.indexOf(x+','+y >=0) {
return true;
}
},
checkGrowth: function() {
if (snake.x == food.x && snake.y==food.y) {
game.score++;
if (game.score %5==0 && game.fps <60){
game.fps++;
}
food.set();
} else {
snake.sections.shift();
}
}
};
food = {
size:null,
x: null,
y:null,
color: '#0FF',
set: function() {
food.size = snake.size;
food.x = (Math.ceil(Math.random() * 10) * snake.size * 4) - snake.size/2;
food.y = (Math.ceil(Math.random() * 10) * snake.size * 3) - snake.size/2;
},
draw: function () {
game.drawBox(food.x, food.y, food.color);
}
};
inverseDirection = {
'up':'down',
'left':'right',
'right':'left',
'down':'up'
};
keys = {
up: [38,75,87],
down: [40,74,83],
left: [37,65,72],
right: [39,68,76],
start_game: [13,32]
};
Object.prototype.getKey = function(value) {
for(var key in this) {
if(this[key] instanceof Array && this[key].indexOf(value) >=0) {
return key;
}
}
return null;
};
addEventListener("keydown", function(e) {
lastKey= keys.getKey(e.keyCode);
if (['up', 'down', 'left', 'right'].indexOf(lastKey) >= 0
&& lastKey !=inveverseDirection[snake.direction]) {
snake.direction = lastKey;
} else if (['start_game'].indexOf(lastKey) >= && game.over) {
game.start();
}
}, false);
var requestAnimationFrame = window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame;
function gameLoop() {
if (game.over == false) {
game.resetCanvas();
game.drawScore();
snake.move();
food.draw();
snake.draw();
game.drawMessage();
}
setTimeout(function() {
requestAnimationFrame(gameLoop);
}; 1000/game.fps);
};
requestAnimationFrame(gameLoop);
var canvas=document.getElementByID(“游戏”);
var context=canvas.getContext(“2d”);
野味、蛇、食物;
游戏={
分数:0,
fps:8,
过:错,
消息:空,
开始:函数(){
game.over=错误;
game.message=null;
游戏。分数=0;
game.fps=8;
snake.init();
食物;
},
停止:函数(){
游戏结束=正确;
game.message='游戏结束-按空格键';
},
抽屉:功能(x、y、尺寸、颜色){
context.fillStyle=颜色;
context.beginPath();
移动到(x-(大小/2),y-(大小/2));
lineTo(x+(大小/2),y-(大小/2));
lineTo(x+(大小/2),y-(大小/2));
lintTo(x-(大小/2),y+(大小/2));
},
drawScore:函数(){
context.fillStyle='#999';
context.font=(canvas.height)+“px影响,无衬线”;
context.textAlign='center';
context.fillText(game.score,canvas.width/2,canvas.height*0.9);
},
drawMessage:function(){
如果(game.message!==null){
context.fillStyle='#00F';
context.strokeStyle='#FFF';
context.font=(canvas.height/10)+“px冲击”;
context.textAlign='center';
context.fillText(game.message,canvas.width/2,canvas.height/2);
context.strokeText(game.message,canvas/2,canvas.height/2;
}
},
resetCanvas:函数(){
clearRect(0,0,canvas.width,canvas.height);
}
};
蛇={
尺寸:canvas.width/40,
x:null,
y:空,
颜色:'#0F0',
方向:'左',
章节:[],
init:function(){
snake.sections=[];
snake.direction='left';
snake.x=canvas.width/2+snake.size/2;
snake.y=canvas.height/2+snake.size/2;
对于(i=snake.x+(5*size.size);i>=snake.x;i-=snake.size){
snake.sections.push(i+','+snake.y);
}
move:function(){
开关(蛇形方向){
案例“向上”:
snake.y-=snake.size;
打破
案例“关闭”:
snake.y+=snake.size;
打破
案例“左”:
snake.x-=snake.size;
打破
案例“正确”:
snake.x+=snake.size;
打破
}
snake.checkCollision();
snake.checkGrowth();
snake.sections.push(snake.x+','+snake.y);
},
绘图:函数(){
for(i=0;i=&&game.over){
game.start();
}
},假);
var requestAnimationFrame=window.requestAnimationFrame | | window.webkitRequestAnimationFrame | | window.mozRequestAnimationFrame;
函数gameLoop(){
如果(game.over==false){
game.resetCanvas();
game.drawScore();
snake.move();
食物;
snake.draw();
game.drawMessage();
}
setTimeout(函数(){
requestAnimationFrame(gameLoop);
};1000/场/秒;
};
requestAnimationFrame(gameLoop);
画布和引导没有问题。但是,代码中有很多格式和语法错误
下次尝试先检查代码中的错误。例如,您可以通过打开inspector在Chrome中查看控制台。以下是一些错误:
- 没有
,函数是getElementByID
getElementByID
- 下一行的
中存在拼写错误: lintTo(x-(大小/2),y+(大小/2))lineTo
- 下一行中没有闭合括号: context.strokeText(game.message,canvas/2,canvas.height/2
- 下面的“>=&&”部分是非法语句 if(['start\u game'].indexOf(lastKey)>=&game.over)
- 以下表达式中有半色而不是逗号: setTimeout(函数(){ requestAnimationFrame(gameLoop); };1000/场/秒
如果你把它们全部清理干净,你会看到画布将正确地显示(你的小提琴)。嘿,非常感谢!我想我是在没有足够注意的情况下匆匆忙忙地完成了最终产品。@gkennedy87没问题,请不要忘了接受答案,以免它出现在未回答的类别中