I am working on a webapp with drag 'n drop functionality. Up to now I used basic HTML5 Dragging but now I switched to using the library interact.js.
I don't know if my problem is specific to this library or of more general kind: Events when dragging and dropping usually fire multiple times (if I have watched it correctly, it also seems to always be exactly 4 times, but no guarantee on that).
I am also using Vue.js and this is my code:
<template>
<v-card
elevation="0"
:id="id"
class="board device-dropzone"
>
<slot class="row"/>
<div
Drop Card here
</div>
</v-card>
</template>
In the slot, an image and div with text get added. Also this is the script:
<script>
import interact from 'interactjs';
export default {
name: 'Devices',
props: ['id', 'acceptsDrop'],
data() {
return {
extendedHover: false,
hoverEnter: false,
timer: null,
totalTime: 2,
};
},
methods: {
resetHover() {
alert('reset');
},
drop(e) {
let wantedId = e.relatedTarget.id.split('-')[0];
console.log(wantedId);
console.warn(e.target);
e.target.classList.remove('hover-drag-over');
this.extendedHover = false;
console.log('-------------dropped');
console.warn('dropped onto device');
this.$emit('dropped-ponent', cardId);
e.target.classList.remove('hover-drag-over'); */
},
dragenter() {
console.log('------------dragenter');
this.hoverEnter = true;
setTimeout(() => {
this.extendedHover = true;
console.log('extended hover detected');
}, 2000);
} */
this.timerID = setTimeout(this.countdown, 3000);
},
dragover(e) {
if (this.acceptsDrop) {
e.target.classList.add('hover-drag-over');
}
},
dragleave(e) {
if (this.acceptsDrop) {
clearInterval(this.timer);
this.timer = null;
this.totalTime = 2;
e.target.classList.remove('hover-drag-over');
this.extendedHover = false;
this.hoverEnter = false;
console.log('................');
console.warn(this.extendedHover);
// this.$emit('cancel-hover');
}
},
countdown() {
console.log('!!!!!!!!!!!!!!!!!!!!');
if (this.hoverEnter === true) {
this.extendedHover = true;
console.log('-------------------');
console.warn(this);
console.warn(this.extendedHover);
this.$emit('long-hover');
}
},
},
mounted() {
// enable draggables to be dropped into this
const dropzone = this;
interact('.device-dropzone').dropzone({
overlap: 0.9,
ondragenter: dropzone.dragenter(),
ondrop: function (event) {
dropzone.drop(event);
},
})
},
};
</script>
The draggable ponent is this one:
<template>
<v-card
class="primary draggable-card"
:id = "id"
:draggable = "false"
@dragover.stop
ref="interactElement"
>
<slot/>
</v-card>
With the script:
<script>
import interact from 'interactjs';
export default {
props: ['id', 'draggable'],
data() {
return {
isInteractAnimating: true,
position: { x: 0, y: 0 },
};
},
methods: {
/* dragStart: (e) => {
e.stopPropagation(); // so dragStart of ParentBoard does not get triggered as well
// eslint-disable-next-line
const target = e.target;
e.dataTransfer.setData('card_id', target.id);
e.dataTransfer.setData('type', 'widget');
// for some delay
setTimeout(() => {
console.log('started dragging');
}, 0);
}, */
dragEndListener: (event) => {
console.warn('+++++++++++++++++++++++++++');
// console.warn(event.currentTarget.id);
if (document.getElementById(event.currentTarget.id)) {
event.currentTarget.parentNode.removeChild(event.currentTarget);
}
},
dragMoveListener: (event) => {
/* eslint-disable */
var target = event.target;
// keep the dragged position in the data-x/data-y attributes
const xCurrent = parseFloat(target.getAttribute('data-x')) || 0;
const yCurrent = parseFloat(target.getAttribute('data-y')) || 0;
const valX = xCurrent + event.dx;
const valY = yCurrent + event.dy;
// translate the element
event.target.style.transform =
`translate(${valX}px, ${valY}px)`
// update the postion attributes
target.setAttribute('data-x', x);
target.setAttribute('data-y', y);
}
/* eslint-enable */
},
mounted() {
const element = this.$refs.interactElement;
console.log(element);
// interact(element).draggable({
const ponent = this;
interact('.draggable-card')
.draggable({
manualStart: true,
onmove: ponent.dragMoveListener,
onend:ponent.dragEndListener,
})
.on('move', function (event) {
var interaction = event.interaction;
// if the pointer was moved while being held down
// and an interaction hasn't started yet
if (interaction.pointerIsDown && !interaction.interacting()) {
var original = event.currentTarget;
// create a clone of the currentTarget element
const clone = event.currentTarget.cloneNode(true);
clone.id = clone.id + "-clone";
clone.classname += " dragged-clone";
// insert the clone to the page
document.body.appendChild(clone);
clone.style.opacity = 0.5;
// start a drag interaction targeting the clone
interaction.start({ name: 'drag' },
event.interactable,
clone);
}
})
.on('end', function (event) {
console.error('end drag');
});
},
/* eslint-enable */
};
</script>
In general the dragging and dropping works. But I don't get why e.g. the drop-event would trigger four times when only dropping a single card. Can anybody help me with this?
I am working on a webapp with drag 'n drop functionality. Up to now I used basic HTML5 Dragging but now I switched to using the library interact.js.
I don't know if my problem is specific to this library or of more general kind: Events when dragging and dropping usually fire multiple times (if I have watched it correctly, it also seems to always be exactly 4 times, but no guarantee on that).
I am also using Vue.js and this is my code:
<template>
<v-card
elevation="0"
:id="id"
class="board device-dropzone"
>
<slot class="row"/>
<div
Drop Card here
</div>
</v-card>
</template>
In the slot, an image and div with text get added. Also this is the script:
<script>
import interact from 'interactjs';
export default {
name: 'Devices',
props: ['id', 'acceptsDrop'],
data() {
return {
extendedHover: false,
hoverEnter: false,
timer: null,
totalTime: 2,
};
},
methods: {
resetHover() {
alert('reset');
},
drop(e) {
let wantedId = e.relatedTarget.id.split('-')[0];
console.log(wantedId);
console.warn(e.target);
e.target.classList.remove('hover-drag-over');
this.extendedHover = false;
console.log('-------------dropped');
console.warn('dropped onto device');
this.$emit('dropped-ponent', cardId);
e.target.classList.remove('hover-drag-over'); */
},
dragenter() {
console.log('------------dragenter');
this.hoverEnter = true;
setTimeout(() => {
this.extendedHover = true;
console.log('extended hover detected');
}, 2000);
} */
this.timerID = setTimeout(this.countdown, 3000);
},
dragover(e) {
if (this.acceptsDrop) {
e.target.classList.add('hover-drag-over');
}
},
dragleave(e) {
if (this.acceptsDrop) {
clearInterval(this.timer);
this.timer = null;
this.totalTime = 2;
e.target.classList.remove('hover-drag-over');
this.extendedHover = false;
this.hoverEnter = false;
console.log('................');
console.warn(this.extendedHover);
// this.$emit('cancel-hover');
}
},
countdown() {
console.log('!!!!!!!!!!!!!!!!!!!!');
if (this.hoverEnter === true) {
this.extendedHover = true;
console.log('-------------------');
console.warn(this);
console.warn(this.extendedHover);
this.$emit('long-hover');
}
},
},
mounted() {
// enable draggables to be dropped into this
const dropzone = this;
interact('.device-dropzone').dropzone({
overlap: 0.9,
ondragenter: dropzone.dragenter(),
ondrop: function (event) {
dropzone.drop(event);
},
})
},
};
</script>
The draggable ponent is this one:
<template>
<v-card
class="primary draggable-card"
:id = "id"
:draggable = "false"
@dragover.stop
ref="interactElement"
>
<slot/>
</v-card>
With the script:
<script>
import interact from 'interactjs';
export default {
props: ['id', 'draggable'],
data() {
return {
isInteractAnimating: true,
position: { x: 0, y: 0 },
};
},
methods: {
/* dragStart: (e) => {
e.stopPropagation(); // so dragStart of ParentBoard does not get triggered as well
// eslint-disable-next-line
const target = e.target;
e.dataTransfer.setData('card_id', target.id);
e.dataTransfer.setData('type', 'widget');
// for some delay
setTimeout(() => {
console.log('started dragging');
}, 0);
}, */
dragEndListener: (event) => {
console.warn('+++++++++++++++++++++++++++');
// console.warn(event.currentTarget.id);
if (document.getElementById(event.currentTarget.id)) {
event.currentTarget.parentNode.removeChild(event.currentTarget);
}
},
dragMoveListener: (event) => {
/* eslint-disable */
var target = event.target;
// keep the dragged position in the data-x/data-y attributes
const xCurrent = parseFloat(target.getAttribute('data-x')) || 0;
const yCurrent = parseFloat(target.getAttribute('data-y')) || 0;
const valX = xCurrent + event.dx;
const valY = yCurrent + event.dy;
// translate the element
event.target.style.transform =
`translate(${valX}px, ${valY}px)`
// update the postion attributes
target.setAttribute('data-x', x);
target.setAttribute('data-y', y);
}
/* eslint-enable */
},
mounted() {
const element = this.$refs.interactElement;
console.log(element);
// interact(element).draggable({
const ponent = this;
interact('.draggable-card')
.draggable({
manualStart: true,
onmove: ponent.dragMoveListener,
onend:ponent.dragEndListener,
})
.on('move', function (event) {
var interaction = event.interaction;
// if the pointer was moved while being held down
// and an interaction hasn't started yet
if (interaction.pointerIsDown && !interaction.interacting()) {
var original = event.currentTarget;
// create a clone of the currentTarget element
const clone = event.currentTarget.cloneNode(true);
clone.id = clone.id + "-clone";
clone.classname += " dragged-clone";
// insert the clone to the page
document.body.appendChild(clone);
clone.style.opacity = 0.5;
// start a drag interaction targeting the clone
interaction.start({ name: 'drag' },
event.interactable,
clone);
}
})
.on('end', function (event) {
console.error('end drag');
});
},
/* eslint-enable */
};
</script>
In general the dragging and dropping works. But I don't get why e.g. the drop-event would trigger four times when only dropping a single card. Can anybody help me with this?
Share Improve this question edited Jun 9, 2020 at 14:32 Brian Tompsett - 汤莱恩 5,89372 gold badges61 silver badges133 bronze badges asked Jun 9, 2020 at 13:27 NotARobotNotARobot 5153 gold badges12 silver badges28 bronze badges 1-
I am debugging a similar issue with the interactjs library.
ondropevent fires twice, then four times, then eight. Did you find the issue in the end? – bigsee Commented Jul 9, 2020 at 15:10
1 Answer
Reset to default 17I was facing a similar issue using the same framework and library. Since there was some logic based on the event firing, it was breaking my app when it fired multiple times.
I suspected that the issue was related to bubbling of events.
The solution in my case was therefore to add event.stopImmediatePropagation() inside my drop(event) handler.
As noted in the referenced article, one should take care when stopping event bubbling that it doesn't have unforeseen consequences elsewhere.