Touch MDB Pro component
MDB Vue custom directive
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This directive allows you to improve the user experience on touch screens by calling methods on the following custom events: pinch, swipe, doubletap, longtap and pan.
Live PreviewBasic usage
Step 1: Import the directive from 'mdbvue'
<script>
import {
mdbTouch
} from "mdbvue";
</script>
Step 2: Add mdbTouch to the directives object
<script>
import {
mdbTouch
} from "mdbvue";
export default {
directives: {
mdbTouch
}
};
</script>
Step 3: Attach the directive, choose one of supported events to an element and pass a callback
<template>
<div v-mdb-touch:doubleTap="zoom" />
</template>
<script>
import {
mdbTouch
} from "mdbvue";
export default {
directives: {
mdbTouch
},
methods: {
zoom() {
//...
}
}
};
</script>
Step 4: For the swipe event you can additionally use modifiers (left, right, up, down)
<template>
<div v-mdb-touch:swipe.left="changeSlide" />
</template>
<script>
import {
mdbTouch
} from "mdbvue";
export default {
directives: {
mdbTouch
},
methods: {
changeSlide() {
//...
}
}
};
</script>
Long tap
The v-mdb-touch:longTap calls the chosen method when the touch
event on the element lasts longer than 1 second.
<template>
<section>
<mdb-view src="https://mdbootstrap.com/img/Photos/Lightbox/Original/img%20(151).webp" imgClass="img-fluid">
<transition enter-active-class="animated fadeIn" leave-active-class="animated fadeOut">
<mdb-mask flex-center v-if="mask" overlay="stylish-strong"
text="Hold the button to remove the mask from the image" />
</transition>
</mdb-view>
<mdb-btn v-mdb-touch:longTap="showImage" class="mx-0 mt-2" color="pink">Tap & hold to show image</mdb-btn>
</section>
</template>
<script>
import {
mdbMask,
mdbView,
mdbBtn,
mdbTouch
} from "mdbvue";
export default {
name: "TouchPage",
components: {
mdbMask,
mdbView,
mdbBtn
},
data() {
return {
mask: true
};
},
methods: {
showImage() {
this.mask = false;
}
},
directives: {
mdbTouch
}
};
</script>
Double tap
The callback on doubleTap event is called with an object containing
origin field - the x and y coordinates of the user's touch. In
this example it allows us to transform origin via CSS
<template>
<div class="img-container" v-mdb-touch:doubleTap="resizeImg" ref="img">
<img src="https://mdbootstrap.com/img/Photos/Lightbox/Original/img%20(147).webp" :style="imgStyle"
class="w-100" />
</div>
</template>
<script>
import {
mdbTouch
} from "mdbvue";
export default {
data() {
return {
scale: 1,
origin: null
};
},
computed: {
imgStyle() {
return {
transform: `scale(${this.scale})`,
transformOrigin: this.origin ?
`${this.origin.x}px ${this.origin.y}px 0` :
"50% 50% 0"
};
}
},
methods: {
resizeImg(e) {
const rect = this.$refs.img.getBoundingClientRect();
this.origin = {
x: e.origin.x - rect.x,
y: e.origin.y - rect.y
};
this.scale === 1 ? (this.scale = 2) : (this.scale = 1);
}
},
directives: {
mdbTouch
}
};
</script>
<style scoped>
.img-container {
width: 100%;
max-height: 600px;
overflow: hidden;
}
.img-container img {
transition: transform 0.4s linear;
}
</style>
Pinch
The pinch event calls the given method with an object containing two keys -
ratio and origin. The first one it the ratio of the distance between user's
fingers on touchend to the same distance on
touchstart - it's particularly useful for scaling images. The
second one, similarly as in doubleTap event, is a pair of coordinates
indicating the middle point between the user's fingers.
<template>
<div class="img-container" v-mdb-touch:pinch="zoom" ref="pinchImg">
<img src="https://mdbootstrap.com/img/Photos/Lightbox/Original/img%20(152).webp" class="img-fluid"
:style="imgStyle2" />
</div>
</template>
<script>
import {
mdbTouch
} from "mdbvue";
export default {
data() {
return {
scale2: 1,
origin2: null
};
},
computed: {
imgStyle2() {
return {
transform: `scale(${this.scale2})`,
transformOrigin: this.origin2 ?
`${this.origin2.x}px ${this.origin2.y}px 0` :
"50% 50% 0"
};
}
},
methods: {
zoom(e) {
const rect = this.$refs.pinchImg.getBoundingClientRect();
this.origin2 = {
x: e.origin.x - rect.x,
y: e.origin.y - rect.y
};
this.scale2 * e.ratio > 1 ?
(this.scale2 *= e.ratio) :
(this.scale2 = 1);
}
},
directives: {
mdbTouch
}
};
</script>
<style scoped>
.img-container {
width: 100%;
max-height: 600px;
overflow: hidden;
}
.img-container img {
transition: transform 0.4s linear;
}
</style>
Swipe
The swipe event comes with several modifiers (left, right, up, down) - each of them will ensure that event will fire only on swipe in that particular direction. If the directive is used without any modifier, the callback method will be called each time the swiping occurs, and the string indicating the direction will be passed as an argument.
<template>
<div v-mdb-touch:swipe.left="swipeLeft" v-mdb-touch:swipe.right="swipeRight">
<mdb-view src="https://mdbootstrap.com/img/Photos/Lightbox/Original/img%20(148).webp" imgClass="img-fluid">
<mdb-mask :overlay="overlays[activeOverlay]" />
</mdb-view>
</div>
</template>
<script>
import {
mdbMask,
mdbView,
mdbTouch
} from "mdbvue";
export default {
components: {
mdbMask,
mdbView
},
data() {
return {
activeOverlay: 0,
overlays: [
"indigo-light",
"indigo-strong",
"blue-light",
"pink-light"
]
};
},
methods: {
swipeRight() {
if (this.activeOverlay === 0)
this.activeOverlay = this.overlays.length - 1;
else this.activeOverlay--;
},
swipeLeft() {
if (this.activeOverlay === this.overlays.length - 1)
this.activeOverlay = 0;
this.activeOverlay++;
}
},
directives: {
mdbTouch
}
};
</script>
Pan
The pan event is useful for dragging elements - every time the user moves a
finger on the element to which the directive is attached to, the given
method is being called with an argument consisting of two keys:
x and y (the values corresponds to the horizontal
and vertical translation).
<template>
<div v-mdb-touch:pan="pan" style="overflow: hidden; height: 400px;">
<img :style="imgStyle3" src="https://mdbootstrap.com/img/Photos/Lightbox/Original/img%20(47).webp" />
</div>
</template>
<script>
import {
mdbTouch
} from "mdbvue";
export default {
data() {
return {
translate: {
x: 0,
y: 0
}
};
},
computed: {
imgStyle3() {
return {
transform: `translate(${this.translate.x}px, ${this.translate.y}px)`
};
}
},
methods: {
pan(e) {
this.translate = {
x: this.translate.x + e.x,
y: this.translate.y + e.y
};
}
},
directives: {
mdbTouch
}
};
</script>