HTML5キャンバスにいくつかの画像を表示するために使用しているWebページがあります。現在、画像が表示されていますが、キャンバスの周りに画像をドラッグアンドドロップできるようにしたいと考えています。
これを行う方法を調べた後、最善の方法は、 http ://www.html5canvastutorials.com/kineticjs/html5-canvas-drag-and-drop-an-image で入手できる KineticJS ライブラリを使用することだと思われます。 -チュートリアル/
私はこれを調べましたが、実際にそれをどのように使用するかはよくわかりません。index.html ファイルにスクリプト src を含めることから始めましたが、表示した画像にドラッグ可能なプロパティを適用するにはどうすればよいですか?
これは私の index.html ページです:
<!DOCTYPE html>
<html>
<head>
<script src = "kinetic.js" type = "text/javascript"></script>
<title>Home</title>
<script src = "drawLevelOneElements.js" type = "text/javascript"></script>
<script src = "layers&analytics.js" type = "text/javascript"></script>
<script src = "startGameDrawGameElementsDrawStartButton.js" type = "text/javascript"></script>
<script src = "interaction.js" type = "text/javascript"></script>
<script src = "dragAndDrop.js" type = "text/javascript"></script>
<script src="http://www.html5canvastutorials.com/libraries/kinetic-v4.0.5.js"></script>
<script src="http://www.html5canvastutorials.com/libraries/kinetic-v4.1.2.js"></script>
</head>
<body onLoad="startGame()">
<section hidden>
<img id="StartButton" src="StartButton.png" alt="Start Button" width="179" height="180" href="javascript:drawLevelOneElements();"/>
<img id="building" src="images/assets/building.png" alt="Asset" draggable="true" ondragstart="drag(event)"/>
<img id="chair" src="images/assets/chair.gif" alt="Asset"/>
<img id="drink" src = "images/assets/drink.jpg" alt="Asset"/>
<img id="food" src = "images/assets/food.gif" alt="Asset"/>
<img id="fridge" src = "images/assets/fridge.png" alt="Asset"/>
<img id="land" src = "images/assets/land.jpg" alt="Asset"/>
<img id="money" src = "images/assets/money.jpg" alt="Asset"/>
<img id="oven" src = "images/assets/oven.jpg" alt="Asset"/>
<img id="table" src = "images/assets/table.gif" alt="Asset"/>
<img id="van" src = "images/assets/van.jpg" alt="Asset"/>
<img id="burger" src = "images/expenses/direct/burger.png" alt="Direct Expense"/>
<img id="chips" src = "images/expenses/direct/chips.png" alt="Direct Expense"/>
<img id="drink" src = "images/expenses/direct/drink.jpg" alt="Direct Expense"/>
<img id="franchiseFee" src = "images/expenses/direct/franchiseFee.jpg" alt="Direct Expense"/>
<img id="wages" src = "images/expenses/direct/wages.jpg" alt="Direct Expense"/>
<img id="admin" src = "images/expenses/indirect/admin.jpg" alt="Indirect Expense"/>
<img id="cleaners" src = "images/expenses/indirect/cleaners.gif" alt="Indirect Expense"/>
<img id="electricity" src = "images/expenses/indirect/electricity.gif" alt="Indirect Expense"/>
<img id="insurance" src = "images/expenses/indirect/insurance.jpg" alt="Indirect Expense"/>
<img id="manager" src = "images/expenses/indirect/manager.jpg" alt="Indirect Expense"/>
<img id="rates" src = "images/expenses/indirect/rates.jpg" alt="Indirect Expense"/>
<img id="training" src = "images/expenses/indirect/training.gif" alt="Indirect Expense"/>
<img id="water" src = "images/expenses/indirect/water.gif" alt="Indirect Expense"/>
<img id="burger" src = "images/income/burger.png" alt="Income"/>
<img id="chips" src = "images/income/chips.png" alt="Income"/>
<img id="drink" src = "images/income/drink.jpg" alt="Income"/>
<img id="creditors" src = "images/liabilities/creditors.gif" alt="Liability"/>
<img id="electricity" src = "images/liabilities/electricity.png" alt="Liability"/>
<img id="food" src = "images/liabilities/food.jpg" alt="Liability"/>
<img id="hirePurchase" src = "images/liabilities/hirePurchase.jpg" alt="Liability"/>
<img id="loan" src = "images/liabilities/loan.png" alt="Liability"/>
<img id="overdraft" src = "images/liabilities/overdraft.jpg" alt="Liability"/>
<img id="payeTax" src = "images/liabilities/payeTax.jpg" alt="Liability"/>
<img id="tax" src = "images/liabilities/tax.jpg" alt="Liability"/>
</section>
<h1>Home</h1>
<p>The purpose of this website is to teach users the basic principles of running a business by playing the game below. <br /><br /></p>
<canvas id="gameCanvas" width="1000" height="500" style="border:1px solid">
Your browser does not support the canvas element.
</canvas>
<br /><br />
<p>Use this paragraph to enter text that provides the user with instructions for how to play the game. <br />
Update the instructions so that they're appropriate to whatever level the user is currently playing.</p>
<script src = "variables&preloadingImages.js" type = "text/javascript"></script>
</body>
これは、キャンバスに画像を描画するために使用している関数です。
function drawLevelOneElements(){
/*First, clear the canvas */
context.clearRect(0, 0, myGameCanvas.width, myGameCanvas.height);
/*This line clears all of the elements that were previously drawn on the canvas. */
/*Then redraw the game elements */
drawGameElements();
/*Call the function to enable drag and drop */
canvasState(document.getElementById('gameCanvas'));
/*Create the four description areas, and place them near the bottom of the canvas */
/*Create boxes with rounded corners for the description areas */
CanvasRenderingContext2D.prototype.drawDescriptionArea = function(x, y, width, height, radius, stroke){
if(typeof stroke == "undefined" ){
stroke = true;
}
if(typeof radius === "undefined"){
radius = 5;
}
this.beginPath();
this.moveTo(x + radius, y);
this.lineTo(x + width - radius, y);
this.quadraticCurveTo(x + width, y, x + width, y + radius);
this.lineTo(x + width, y + height - radius);
this.quadraticCurveTo(x + width, y + height, x + width - radius, y + height);
this.lineTo(x + radius, y + height);
this.quadraticCurveTo(x, y + height, x, y + height - radius);
this.lineTo(x, y + radius);
this.quadraticCurveTo(x, y, x + radius, y);
this.closePath();
if(stroke){
context.stroke();
}
}
context.drawDescriptionArea(70, 400, 120, 70);
context.font = '25pt Calibri';
context.strokeText('Asset', 90, 440);
context.drawDescriptionArea(300, 400, 120, 70);
context.strokeText('Liability', 310, 440);
context.drawDescriptionArea(540, 400, 120, 70);
context.strokeText('Income', 550, 440);
context.drawDescriptionArea(750, 400, 180, 70);
context.strokeText('Expenditure', 760, 440);
/*Now draw the images to the canvas */
/*First, create variables for the x & y coordinates of the image that will be drawn.
the x & y coordinates should hold random numbers, so that the images will be
drawn in random locations on the canvas.*/
var imageX = Math.floor(Math.random()*100);
var imageY = Math.floor(Math.random()*100);
var imageWidth = 50;
var imageHeight = 50;
/*Create a 'table' of positions that the images will be drawn to */
var imagePositionsX = [20, 80, 140, 200, 260, 320, 380, 440, 500, 560];
var imagePositionsY = [20, 60, 100, 140, 180, 220, 260, 300, 340, 380];
/*Draw all images from assetsImageArray */
/*Use a while loop to loop through the array, get each item and draw it. */
var arrayIteration = 0;
console.log('All Images Array length: ' + allImagesArray.length); /*Display the length of the array in the console, to check it's holding the correct number of images. */
while(arrayIteration < allImagesArray.length){
//var randomPositionX = Math.floor(Math.random()*10);
//var randomPositionY = Math.floor(Math.random()*10);
context.drawImage(allImagesArray[arrayIteration], imageX, imageY, imageWidth, imageHeight); /*Declare variables for image height and width, so it can be accessed elsewhere */
console.log(arrayIteration); /*Display the current array position that's being drawn */
arrayIteration = arrayIteration+1;
/*Now try changing the values of imageX & imageY so that the next image is drawn to a
different location*/
//imageX = imagePositionsX[randomPositionX]; /* imageX+(Math.floor(Math.random()*100)); */
//imageY = imagePositionsY[randomPositionY]; /* imageY+(Math.floor(Math.random()*100)); */
imageX = Math.floor(Math.random()*950);
imageY = Math.floor(Math.random()*350);
}
}
この関数の下部にある while ループは、JavaScript に描画するすべての画像を読み込んだ配列をループ処理し、それぞれをキャンバス上のランダムな場所に描画します。
これは事実上、画像が JavaScript オブジェクトになるポイントであるため、ここでそれぞれの「ドラッグ可能」プロパティを true に設定する必要があると思います。
行に追加してみました
allImagesArray[arrayIteration].draggable = "true";
しかし、ブラウザのコンソールに「Uncaught TypeError: プロパティ 'ドラッグ可能' を未定義に設定できません」というエラーが表示されます。
これがなぜなのか、どうすれば正しくできるのか誰か知っていますか?
編集
allImagesArray[arrayIteration].setDraggable = "true";わかりました、whileループの行のすぐ下に行を移動することでそのエラーを取り除きましたがcontext.drawImage...、キャンバスの周りに画像をドラッグアンドドロップすることはまだできません.
ドラッグアンドドロップ機能を画像に追加するために何をする必要があるか知っている人はいますか?