Question

我正在创建一个视频游戏，我想要一个按钮消失，一旦我点击它并移动到下一个屏幕。我可以通过我的html和js文件设置按钮的功能，但我不确定如何点击后它会消失。

我的HTML代码：

<html>
<head>
<title> Pong </title>
<link type = "text/css" href = "main.css" rel = "stylesheet">
</head>
<canvas id="gameCanvas" width="1350" height="600"></canvas>
<body>
<button id = 'easy_click' onclick="EasyChange()"> Easy </button>
<button id = 'int_change' onclick="intChange()"> Intermediate </button>
<button id = "hard_change" onclick="hardChange()"> Hard </button>
</body>
<script src = "functions.js"></script>

</html>

这是我的JS代码：

    var canvas;
var canvasContext;
var ballX = 50;
var ballY = 50;
var ballSpeedX = 20;
var ballSpeedY = 10
var menuScreen = false;
var name = "Developed by Jonah Johnson";
var player1Score = 0;
var player2Score = 0;
const WINNING_SCORE = 10;
var easybutton = "Easy";
var hardButton = "Hard";
var intButton = "Intermediate";
var diffLevelEasy = false;
var diffLevelMedium = true;
var diffLevelHard = false;
var showingWinScreen = true;

var paddle1Y = 250;
var paddle2Y = 250;
const PADDLE_THICKNESS = 10;
const PADDLE_HEIGHT = 100;

function calculateMousePos(evt) {
    var rect = canvas.getBoundingClientRect();
    var root = document.documentElement;
    var mouseX = evt.clientX - rect.left - root.scrollLeft;
    var mouseY = evt.clientY - rect.top - root.scrollTop;
    return {
        x:mouseX,
        y:mouseY
    };
}

//changing of difficulty
//easy changing
function EasyChange() {
    diffLevelEasy = true;
    diffLevelMedium = false;
    diffLevelHard = false;
    showingWinScreen = false;
}

function intChange() {
    diffLevelEasy = false;
    diffLevelMedium = true;
    diffLevelHard = false;
    showingWinScreen = false;

}

function hardChange() {
    diffLevelEasy = false;
    diffLevelMedium = false;
    diffLevelHard = true;
    showingWinScreen = false;
}

function handleMouseClick(evt) {
    if(showingWinScreen) {
        player1Score = 0;
        player2Score = 0;
        showingWinScreen = false;
    }
}
// getting an easy medium
function handleMouseClick(evt) {
   if(easybutton) {
       diffLevelEasy = true;
       diffLevelMedium = false;
       diffLevelHard = false;
       showingWinScreen = false;
   }
}
//getting medium
function handleMouseClick(evt) {
    if(intButton) {
        diffLevelEasy = false;
       diffLevelMedium = true;
       diffLevelHard = false;
       showingWinScreen = false;

    }
}
//getting hard
function handleMouseClick(evt) {
    if(hardButton) {
        diffLevelEasy = false;
        diffLevelMedium = false;
        diffLevelHard = true;
        showingWinScreen = false;
    }
}


window.onload = function() {
    canvas = document.getElementById('gameCanvas');
    canvasContext = canvas.getContext('2d');

    var framesPerSecond = 30;
    setInterval(function() {
            moveEverything();
            drawEverything();   
        }, 1000/framesPerSecond);

    canvas.addEventListener('mousedown', handleMouseClick);

    canvas.addEventListener('mousemove',
        function(evt) {
            var mousePos = calculateMousePos(evt);
            paddle1Y = mousePos.y - (PADDLE_HEIGHT/2);
        });
}

function ballReset() {
    if(player1Score >= WINNING_SCORE ||
        player2Score >= WINNING_SCORE) {

        showingWinScreen = true;

    }

    ballSpeedX = -ballSpeedX;
    ballX = canvas.width/2;
    ballY = canvas.height/2;
}

function computerMovement() {   
    /// ai movement
    //easy
    if(diffLevelEasy === true) {
    var paddle2YCenter = paddle2Y + (PADDLE_HEIGHT/2);
    if(paddle2YCenter < ballY - 35) {
        paddle2Y = paddle2Y + 2;
    } else if(paddle2YCenter > ballY + 35) {
        paddle2Y = paddle2Y - 2;
    }
}
    //medium
    else if(diffLevelMedium === true) {
    var paddle2YCenter = paddle2Y + (PADDLE_HEIGHT/2);
    if(paddle2YCenter < ballY - 35) {
        paddle2Y = paddle2Y + 12;
    } else if(paddle2YCenter > ballY + 35) {
        paddle2Y = paddle2Y - 12;
    }
}
    //hard
    else if(diffLevelHard === true) {
    var paddle2YCenter = paddle2Y + (PADDLE_HEIGHT/2);
    if(paddle2YCenter < ballY - 35) {
        paddle2Y = paddle2Y + 18;
    } else if(paddle2YCenter > ballY + 35) {
        paddle2Y = paddle2Y - 18;
    }
    }
}


function moveEverything() {
    if(showingWinScreen) {                         //showing win screen
        return;
    }

    computerMovement();

    ballX = ballX + ballSpeedX;
    ballY = ballY + ballSpeedY;

    if(ballX < 0) {
        if(ballY > paddle1Y &&
            ballY < paddle1Y+PADDLE_HEIGHT) {
            ballSpeedX = -ballSpeedX;

            var deltaY = ballY
                    -(paddle1Y+PADDLE_HEIGHT/2);
            ballSpeedY = deltaY * 0.35;
        } else {
            player2Score++; // must be BEFORE ballReset()
            ballReset();
        }
    }
    if(ballX > canvas.width) {
        if(ballY > paddle2Y &&
            ballY < paddle2Y+PADDLE_HEIGHT) {
            ballSpeedX = -ballSpeedX;

            var deltaY = ballY
                    -(paddle2Y+PADDLE_HEIGHT/2);
            ballSpeedY = deltaY * 0.35;
        } else {
            player1Score++; // must be BEFORE ballReset()
            ballReset();    
        }
    }
    if(ballY < 0) {
        ballSpeedY = -ballSpeedY;
    }
    if(ballY > canvas.height) {
        ballSpeedY = -ballSpeedY;
    }
}

function drawNet() {
    for(var i=0;i<canvas.height;i+=40) {
        colorRect(canvas.width/2-1,i,2,20,'white');
    }
}

function drawEverything() {
    // next line blanks out the screen with black
    colorRect(0,0,canvas.width,canvas.height,'black');


    if(showingWinScreen) {
        canvasContext.fillStyle = 'white';

        if(player1Score >= WINNING_SCORE) {
            canvasContext.fillText("Left Player Won", 350, 200);
        } else if(player2Score >= WINNING_SCORE) {
            canvasContext.fillText("Right Player Won", 350, 200);
        }

        canvasContext.fillText("click to continue", 350, 500);
        canvasContext.fillText("Difficulty:", 50, 50);
        canvasContext.fillText(easybutton, 50, 100);
        canvasContext.fillText(intButton, 50, 200);
        canvasContext.fillText(hardButton, 50, 300);
        return;
    }

    drawNet();

    // this is left player paddle
    colorRect(0,paddle1Y,PADDLE_THICKNESS,PADDLE_HEIGHT,'white');

    // this is right computer paddle
    colorRect(canvas.width-PADDLE_THICKNESS,paddle2Y,PADDLE_THICKNESS,PADDLE_HEIGHT,'white');

    // next line draws the ball
    colorCircle(ballX, ballY, 10, 'white');

    canvasContext.fillText(player1Score, 100, 100);
    canvasContext.fillText(player2Score, canvas.width-100, 100);
    canvasContext.fillText(name, 100, 590);
}

function colorCircle(centerX, centerY, radius, drawColor) {
    canvasContext.fillStyle = drawColor;
    canvasContext.beginPath();
    canvasContext.arc(centerX, centerY, radius, 0,Math.PI*2,true);
    canvasContext.fill();
}

function colorRect(leftX,topY, width,height, drawColor) {
    canvasContext.fillStyle = drawColor;
    canvasContext.fillRect(leftX,topY, width,height);
}
//sets how hard the game is
if(diffLevel = diffLevelEasy) {
var paddle2YCenter = paddle2Y + (PADDLE_HEIGHT/2);
    if(paddle2YCenter < ballY - 35) {
        paddle2Y = paddle2Y + 2;
    } else if(paddle2YCenter > ballY + 35) {
        paddle2Y = paddle2Y - 2;
    }
}

我只是想在点击时删除按钮，那我该怎么做？

Answer 1

在网上找到这个尝试

Name  Cri  City  Wanted Val  
P1    B    BKN       ?
P2    D    DET       ?

Answer 2

只需致电evt.target.remove()，它就会将其从DOM中删除。

Answer 3

为了将来的可扩展性，可能性，可维护性和最少的代码更改，我将按钮作为参数发送给事件处理程序：

<button id = 'easy_click' onclick="EasyChange(this)"> Easy </button>
<button id = 'int_change' onclick="intChange(this)"> Intermediate </button>
<button id = "hard_change" onclick="hardChange(this)"> Hard </button>

然后在处理函数中设置样式：

function EasyChange(btn) {
    diffLevelEasy = true;
    diffLevelMedium = false;
    diffLevelHard = false;
    showingWinScreen = false;
    btn.style.display='none';

}

function intChange(btn) {
    diffLevelEasy = false;
    diffLevelMedium = true;
    diffLevelHard = false;
    showingWinScreen = false;
btn.style.display='none';
}

function hardChange(btn) {
    diffLevelEasy = false;
    diffLevelMedium = false;
    diffLevelHard = true;
    showingWinScreen = false;
    btn.style.display='none';
}

要恢复按钮使用：

btn.style.display='none';

或者，要停止使用DOM跳转：

btn.style.visibility='hidden';

和

btn.style.visibility='visible';

另请告知我发布的时间和地点，因为网页听起来很棒。

点击javascript后，HTML按钮消失

3 个答案: