From bd80fe4e0571b9d30199318cd83eca42e89378ab Mon Sep 17 00:00:00 2001
From: neverland <chenjiahan@buaa.edu.cn>
Date: Fri, 13 Apr 2018 15:26:41 +0800
Subject: [PATCH] [Improvement] add touch mixin (#869)

---
 packages/cell-swipe/index.vue            | 32 ++++++++----------------
 packages/image-preview/image-preview.vue | 18 ++++---------
 packages/mixins/popup/index.js           | 25 ++++++------------
 packages/mixins/touch.js                 | 25 ++++++++++++++++++
 packages/pull-refresh/index.vue          | 15 ++++-------
 packages/swipe/index.vue                 | 19 +++++---------
 packages/tabs/index.vue                  | 32 ++++++------------------
 7 files changed, 66 insertions(+), 100 deletions(-)
 create mode 100644 packages/mixins/touch.js

diff --git a/packages/cell-swipe/index.vue b/packages/cell-swipe/index.vue
index 221dc3411..f9bbb5501 100644
--- a/packages/cell-swipe/index.vue
+++ b/packages/cell-swipe/index.vue
@@ -23,12 +23,15 @@
 <script>
 import create from '../utils/create';
 import Clickoutside from '../utils/clickoutside';
+import Touch from '../mixins/touch';
 
 const THRESHOLD = 0.15;
 
 export default create({
   name: 'cell-swipe',
 
+  mixins: [Touch],
+
   props: {
     onClose: Function,
     leftWidth: {
@@ -96,9 +99,7 @@ export default create({
 
     startDrag(event) {
       this.draging = true;
-      this.direction = '';
-      this.startX = event.touches[0].clientX;
-      this.startY = event.touches[0].clientY;
+      this.touchStart(event);
 
       if (this.opened) {
         this.startX -= this.offset;
@@ -106,24 +107,17 @@ export default create({
     },
 
     onDrag(event) {
-      const offsetTop = event.touches[0].clientY - this.startY;
-      const offsetLeft = event.touches[0].clientX - this.startX;
+      this.touchMove(event);
+      const { deltaX } = this;
 
-      if ((offsetLeft < 0 && -offsetLeft > this.rightWidth) ||
-        (offsetLeft > 0 && offsetLeft > this.leftWidth) ||
-        (offsetLeft > 0 && !this.leftWidth) ||
-        (offsetLeft < 0 && !this.rightWidth)) {
+      if ((deltaX < 0 && (-deltaX > this.rightWidth || !this.rightWidth)) ||
+        (deltaX > 0 && (deltaX > this.leftWidth || deltaX > 0 && !this.leftWidth))) {
         return;
       }
 
-      const y = Math.abs(offsetTop);
-      const x = Math.abs(offsetLeft);
-      const swiping = !(x < 5 || (x >= 5 && y >= x * 1.73));
-      this.direction = this.direction || this.getDirection(event.touches[0]);
-
-      if (swiping && this.direction === 'horizontal') {
+      if (this.direction === 'horizontal') {
         event.preventDefault();
-        this.swipeMove(offsetLeft);
+        this.swipeMove(deltaX);
       };
     },
 
@@ -134,12 +128,6 @@ export default create({
       };
     },
 
-    getDirection(touch) {
-      const offsetX = Math.abs(touch.clientX - this.startX);
-      const offsetY = Math.abs(touch.clientY - this.startY);
-      return offsetX > offsetY ? 'horizontal' : offsetX < offsetY ? 'vertical' : '';
-    },
-
     onClick(position = 'outside') {
       if (!this.offset) {
         return;
diff --git a/packages/image-preview/image-preview.vue b/packages/image-preview/image-preview.vue
index 5a19270a1..65e940b05 100644
--- a/packages/image-preview/image-preview.vue
+++ b/packages/image-preview/image-preview.vue
@@ -3,7 +3,7 @@
     v-show="value"
     class="van-image-preview"
     @touchstart="onTouchStart"
-    @touchmove="onTouchMove"
+    @touchmove.prevent="touchMove"
     @touchend="onTouchEnd"
     @touchcancel="onTouchEnd"
   >
@@ -20,11 +20,12 @@ import create from '../utils/create';
 import Popup from '../mixins/popup';
 import Swipe from '../swipe';
 import SwipeItem from '../swipe-item';
+import Touch from '../mixins/touch';
 
 export default create({
   name: 'image-preview',
 
-  mixins: [Popup],
+  mixins: [Popup, Touch],
 
   components: {
     Swipe,
@@ -52,23 +53,14 @@ export default create({
   methods: {
     onTouchStart(event) {
       this.touchStartTime = new Date();
-      this.touchStartX = event.touches[0].clientX;
-      this.touchStartY = event.touches[0].clientY;
-      this.deltaX = 0;
-      this.deltaY = 0;
-    },
-
-    onTouchMove(event) {
-      event.preventDefault();
-      this.deltaX = event.touches[0].clientX - this.touchStartX;
-      this.deltaY = event.touches[0].clientY - this.touchStartY;
+      this.touchStart(event);
     },
 
     onTouchEnd(event) {
       event.preventDefault();
       // prevent long tap to close component
       const deltaTime = new Date() - this.touchStartTime;
-      if (deltaTime < 100 && Math.abs(this.deltaX) < 20 && Math.abs(this.deltaY) < 20) {
+      if (deltaTime < 100 && this.offsetX < 20 && this.offsetY < 20) {
         this.$emit('input', false);
       }
     }
diff --git a/packages/mixins/popup/index.js b/packages/mixins/popup/index.js
index 0e4630766..9b9db2a46 100644
--- a/packages/mixins/popup/index.js
+++ b/packages/mixins/popup/index.js
@@ -2,8 +2,11 @@ import manager from './manager';
 import context from './context';
 import scrollUtils from '../../utils/scroll';
 import { on, off } from '../../utils/event';
+import Touch from '../touch';
 
 export default {
+  mixins: [Touch],
+
   props: {
     // whether to show popup
     value: Boolean,
@@ -42,10 +45,6 @@ export default {
 
   created() {
     this._popupId = 'popup-' + context.plusKey('id');
-    this.pos = {
-      x: 0,
-      y: 0
-    };
   },
 
   mounted() {
@@ -107,7 +106,7 @@ export default {
         context.lockCount--;
         if (!context.lockCount) {
           document.body.classList.remove('van-overflow-hidden');
-          off(document, 'touchstart', this.onTouchStart);
+          off(document, 'touchstart', this.touchStart);
           off(document, 'touchmove', this.onTouchMove);
         }
       }
@@ -126,21 +125,11 @@ export default {
       }
     },
 
-    onTouchStart(e) {
-      this.pos = {
-        x: e.touches[0].clientX,
-        y: e.touches[0].clientY
-      };
-    },
-
     onTouchMove(e) {
-      const { pos } = this;
-      const dx = e.touches[0].clientX - pos.x;
-      const dy = e.touches[0].clientY - pos.y;
-      const direction = dy > 0 ? '10' : '01';
+      this.touchMove(e);
+      const direction = this.deltaY > 0 ? '10' : '01';
       const el = scrollUtils.getScrollEventTarget(e.target, this.$el);
       const { scrollHeight, offsetHeight, scrollTop } = el;
-      const isVertical = Math.abs(dx) < Math.abs(dy);
 
       let status = '11';
 
@@ -154,7 +143,7 @@ export default {
       /* istanbul ignore next */
       if (
         status !== '11' &&
-        isVertical &&
+        this.direction === 'vertical' &&
         !(parseInt(status, 2) & parseInt(direction, 2))
       ) {
         e.preventDefault();
diff --git a/packages/mixins/touch.js b/packages/mixins/touch.js
new file mode 100644
index 000000000..a5affbfd9
--- /dev/null
+++ b/packages/mixins/touch.js
@@ -0,0 +1,25 @@
+export default {
+  methods: {
+    touchStart(event) {
+      this.direction = '';
+      this.deltaX = 0;
+      this.deltaY = 0;
+      this.offsetX = 0;
+      this.offsetY = 0;
+      this.startX = event.touches[0].clientX;
+      this.startY = event.touches[0].clientY;
+    },
+
+    touchMove(event) {
+      const touch = event.touches[0];
+      this.deltaX = touch.clientX - this.startX;
+      this.deltaY = touch.clientY - this.startY;
+      this.offsetX = Math.abs(this.deltaX);
+      this.offsetY = Math.abs(this.deltaY);
+
+      if (!this.direction) {
+        this.direction = this.offsetX > this.offsetY ? 'horizontal' : this.offsetX < this.offsetY ? 'vertical' : '';
+      }
+    }
+  }
+};
diff --git a/packages/pull-refresh/index.vue b/packages/pull-refresh/index.vue
index 038f33423..2ba40b611 100644
--- a/packages/pull-refresh/index.vue
+++ b/packages/pull-refresh/index.vue
@@ -31,10 +31,13 @@
 <script>
 import create from '../utils/create';
 import scrollUtils from '../utils/scroll';
+import Touch from '../mixins/touch';
 
 export default create({
   name: 'pull-refresh',
 
+  mixins: [Touch],
+
   props: {
     pullingText: String,
     loosingText: String,
@@ -88,8 +91,7 @@ export default create({
       }
       if (this.getCeiling()) {
         this.duration = 0;
-        this.startX = event.touches[0].clientX;
-        this.startY = event.touches[0].clientY;
+        this.touchStart(event);
       }
     },
 
@@ -98,8 +100,7 @@ export default create({
         return;
       }
 
-      this.deltaY = event.touches[0].clientY - this.startY;
-      this.direction = this.getDirection(event.touches[0]);
+      this.touchMove(event);
 
       if (!this.ceiling && this.getCeiling()) {
         this.duration = 0;
@@ -157,12 +158,6 @@ export default create({
       if (status !== this.status) {
         this.status = status;
       }
-    },
-
-    getDirection(touch) {
-      const distanceX = Math.abs(touch.clientX - this.startX);
-      const distanceY = Math.abs(touch.clientY - this.startY);
-      return distanceX > distanceY ? 'horizontal' : distanceX < distanceY ? 'vertical' : '';
     }
   }
 });
diff --git a/packages/swipe/index.vue b/packages/swipe/index.vue
index 520159da7..74a266520 100644
--- a/packages/swipe/index.vue
+++ b/packages/swipe/index.vue
@@ -23,10 +23,13 @@
 
 <script>
 import create from '../utils/create';
+import Touch from '../mixins/touch';
 
 export default create({
   name: 'swipe',
 
+  mixins: [Touch],
+
   props: {
     autoplay: Number,
     loop: {
@@ -121,11 +124,8 @@ export default create({
     onTouchStart(event) {
       clearTimeout(this.timer);
 
-      this.deltaX = 0;
-      this.direction = '';
       this.currentDuration = 0;
-      this.startX = event.touches[0].clientX;
-      this.startY = event.touches[0].clientY;
+      this.touchStart(event);
 
       if (this.active <= -1) {
         this.move(this.count);
@@ -136,19 +136,18 @@ export default create({
     },
 
     onTouchMove(event) {
-      this.direction = this.direction || this.getDirection(event.touches[0]);
+      this.touchMove(event);
 
       if (this.direction === 'horizontal') {
         event.preventDefault();
         event.stopPropagation();
-        this.deltaX = event.touches[0].clientX - this.startX;
         this.move(0, this.range(this.deltaX, [-this.width, this.width]));
       }
     },
 
     onTouchEnd() {
       if (this.deltaX) {
-        this.move(Math.abs(this.deltaX) > 50 ? (this.deltaX > 0 ? -1 : 1) : 0);
+        this.move(this.offsetX > 50 ? (this.deltaX > 0 ? -1 : 1) : 0);
         this.currentDuration = this.duration;
       }
       this.autoPlay();
@@ -202,12 +201,6 @@ export default create({
       }
     },
 
-    getDirection(touch) {
-      const offsetX = Math.abs(touch.clientX - this.startX);
-      const offsetY = Math.abs(touch.clientY - this.startY);
-      return offsetX > offsetY ? 'horizontal' : offsetX < offsetY ? 'vertical' : '';
-    },
-
     range(num, arr) {
       return Math.min(Math.max(num, arr[0]), arr[1]);
     }
diff --git a/packages/tabs/index.vue b/packages/tabs/index.vue
index 827b76524..8cde5e315 100644
--- a/packages/tabs/index.vue
+++ b/packages/tabs/index.vue
@@ -38,10 +38,13 @@ import { raf } from '../utils/raf';
 import { on, off } from '../utils/event';
 import VanNode from '../utils/node';
 import scrollUtils from '../utils/scroll';
+import Touch from '../mixins/touch';
 
 export default create({
   name: 'tabs',
 
+  mixins: [Touch],
+
   components: {
     VanNode
   },
@@ -148,22 +151,10 @@ export default create({
     swipeableHandler(init) {
       const swipeableEl = this.$refs.content;
 
-      (init ? on : off)(swipeableEl, 'touchstart', this.onTouchStart, false);
-      (init ? on : off)(swipeableEl, 'touchmove', this.onTouchMove, false);
-      (init ? on : off)(swipeableEl, 'touchend', this.onTouchEnd, false);
-      (init ? on : off)(swipeableEl, 'touchcancel', this.onTouchEnd, false);
-    },
-
-    // record swipe touch start position
-    onTouchStart(event) {
-      this.startX = event.touches[0].clientX;
-      this.startY = event.touches[0].clientY;
-    },
-
-    // watch swipe touch move
-    onTouchMove(event) {
-      this.deltaX = event.touches[0].clientX - this.startX;
-      this.direction = this.getDirection(event.touches[0]);
+      (init ? on : off)(swipeableEl, 'touchstart', this.touchStart);
+      (init ? on : off)(swipeableEl, 'touchmove', this.touchMove);
+      (init ? on : off)(swipeableEl, 'touchend', this.onTouchEnd);
+      (init ? on : off)(swipeableEl, 'touchcancel', this.onTouchEnd);
     },
 
     // watch swipe touch end
@@ -172,7 +163,7 @@ export default create({
       const minSwipeDistance = 50;
 
       /* istanbul ignore else */
-      if (direction === 'horizontal' && Math.abs(deltaX) >= minSwipeDistance) {
+      if (direction === 'horizontal' && this.offsetX >= minSwipeDistance) {
         /* istanbul ignore else */
         if (deltaX > 0 && curActive !== 0) {
           this.curActive = curActive - 1;
@@ -182,13 +173,6 @@ export default create({
       }
     },
 
-    // get swipe direction
-    getDirection(touch) {
-      const distanceX = Math.abs(touch.clientX - this.startX);
-      const distanceY = Math.abs(touch.clientY - this.startY);
-      return distanceX > distanceY ? 'horizontal' : distanceX < distanceY ? 'vertical' : '';
-    },
-
     // adjust tab position
     onScroll() {
       const scrollTop = scrollUtils.getScrollTop(this.scrollEl);