HTML5 Canvas Select Shape by Name Tutorial

To select shapes by name with Konva, we can use the find() method using the . selector.
The find() method returns an array of nodes that match the selector string.

Konva Select Shape by Name Demoview raw
<!DOCTYPE html>
<html>
<head>
<script src="https://unpkg.com/[email protected]/konva.min.js"></script>
<meta charset="utf-8" />
<title>Konva Select Shape by Name Demo</title>
<style>
body {
margin: 0;
padding: 0;
overflow: hidden;
background-color: #f0f0f0;
}
#buttons {
position: absolute;
top: 5px;
left: 10px;
}
#buttons > input {
padding: 10px;
display: block;
margin-top: 5px;
}
</style>
</head>
<body>
<div id="container"></div>
<div id="buttons">
<input type="button" id="activate" value="Activate rectangle" />
</div>
<script>
var width = window.innerWidth;
var height = window.innerHeight;

var stage = new Konva.Stage({
container: 'container',
width: width,
height: height,
});

var layer = new Konva.Layer();
for (var n = 0; n < 10; n++) {
var circle = new Konva.Circle({
x: Math.random() * stage.width(),
y: Math.random() * stage.height(),
radius: Math.random() * 50 + 25,
fill: 'red',
strokeWidth: 3,
stroke: 'black',
});

layer.add(circle);
}

var rect1 = new Konva.Rect({
x: 250,
y: 90,
width: 100,
height: 50,
fill: 'green',
strokeWidth: 3,
stroke: 'black',
offset: {
x: 50,
y: 25,
},
draggable: true,
name: 'rectangle',
});

var rect2 = new Konva.Rect({
x: 70,
y: 90,
width: 100,
height: 50,
fill: 'green',
strokeWidth: 3,
stroke: 'black',
offset: {
x: 50,
y: 25,
},
draggable: true,
name: 'rectangle',
});
layer.add(rect1);
layer.add(rect2);
stage.add(layer);

var tweens = [];

document.getElementById('activate').addEventListener(
'click',
function () {
// select shapes by name
var shapes = stage.find('.rectangle');

// if there are currently any active tweens, destroy them
// before creating new ones
for (var n = 0; n < tweens.length; n++) {
tweens[n].destroy();
}

// apply transition to all nodes in the array
shapes.forEach(function (shape) {
tweens.push(
new Konva.Tween({
node: shape,
duration: 1,
scaleX: Math.random() * 2,
scaleY: Math.random() * 2,
easing: Konva.Easings.ElasticEaseOut,
}).play()
);
});
},
false
);
</script>
</body>
</html>
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