[new feature] Stepper: support long press gesture (#3711)

src/stepper/index.js

@@ -2,6 +2,9 @@ import { createNamespace, isDef, suffixPx } from '../utils';
 
 const [createComponent, bem] = createNamespace('stepper');
 
+const LONG_PRESS_START_TIME = 600;
+const LONG_PRESS_INTERVAL = 200;
+
 export default createComponent({
   props: {
     value: null,
@@ -78,19 +81,21 @@ export default createComponent({
       const { value } = event.target;
       const formatted = this.format(value);
 
-      if (!this.asyncChange) {
+      if (this.asyncChange) {
+        event.target.value = this.currentValue;
+        this.$emit('input', formatted);
+        this.$emit('change', formatted);
+      } else {
         if (+value !== formatted) {
           event.target.value = formatted;
         }
         this.currentValue = formatted;
-      } else {
-        event.target.value = this.currentValue;
-        this.$emit('input', formatted);
-        this.$emit('change', formatted);
       }
     },
 
-    onChange(type) {
+    onChange() {
+      const { type } = this;
+
       if (this[`${type}Disabled`]) {
         this.$emit('overlimit', type);
         return;
@@ -99,12 +104,13 @@ export default createComponent({
       const diff = type === 'minus' ? -this.step : +this.step;
       const value = Math.round((this.currentValue + diff) * 100) / 100;
 
-      if (!this.asyncChange) {
-        this.currentValue = this.range(value);
-      } else {
+      if (this.asyncChange) {
         this.$emit('input', value);
         this.$emit('change', value);
+      } else {
+        this.currentValue = this.range(value);
       }
+
       this.$emit(type);
     },
 
@@ -120,19 +126,56 @@ export default createComponent({
       if (this.currentValue === 0) {
         event.target.value = this.currentValue;
       }
+    },
+
+    longPressStep() {
+      this.longPressTimer = setTimeout(() => {
+        this.onChange(this.type);
+        this.longPressStep(this.type);
+      }, LONG_PRESS_INTERVAL);
+    },
+
+    onTouchStart(type) {
+      clearTimeout(this.longPressTimer);
+      this.isLongPress = false;
+
+      this.longPressTimer = setTimeout(() => {
+        this.isLongPress = true;
+        this.onChange();
+        this.longPressStep();
+      }, LONG_PRESS_START_TIME);
+    },
+
+    onTouchEnd(event) {
+      clearTimeout(this.longPressTimer);
+
+      if (this.isLongPress) {
+        event.preventDefault();
+      }
     }
   },
 
   render(h) {
-    const onChange = type => () => {
-      this.onChange(type);
-    };
+    const createListeners = type => ({
+      on: {
+        click: () => {
+          this.type = type;
+          this.onChange();
+        },
+        touchstart: () => {
+          this.type = type;
+          this.onTouchStart(type);
+        },
+        touchend: this.onTouchEnd,
+        touchcancel: this.onTouchEnd
+      }
+    });
 
     return (
       <div class={bem()}>
         <button
           class={bem('minus', { disabled: this.minusDisabled })}
-          onClick={onChange('minus')}
+          {...createListeners('minus')}
         />
         <input
           type="number"
@@ -150,7 +193,7 @@ export default createComponent({
         />
         <button
           class={bem('plus', { disabled: this.plusDisabled })}
-          onClick={onChange('plus')}
+          {...createListeners('plus')}
         />
       </div>
     );

src/stepper/test/index.spec.js

@@ -1,5 +1,5 @@
 import Stepper from '..';
-import { mount } from '../../../test/utils';
+import { mount, later } from '../../../test/utils';
 
 test('disabled stepper', () => {
   const wrapper = mount(Stepper, {
@@ -39,6 +39,27 @@ test('click button', () => {
   expect(wrapper.emitted('overlimit')).toEqual([['plus'], ['minus']]);
 });
 
+test('long press', async () => {
+  const wrapper = mount(Stepper, {
+    propsData: {
+      value: 1
+    }
+  });
+
+  const plus = wrapper.find('.van-stepper__plus');
+
+  plus.trigger('touchstart');
+  plus.trigger('touchend');
+  plus.trigger('click');
+
+  expect(wrapper.emitted('input')[0][0]).toEqual(2);
+
+  plus.trigger('touchstart');
+  await later(1000);
+  plus.trigger('touchend');
+  expect(wrapper.emitted('input')).toEqual([[2], [3], [4]]);
+});
+
 test('correct value when value is not correct', () => {
   const wrapper = mount(Stepper, {
     propsData: {
@@ -117,3 +138,41 @@ test('input width', () => {
   });
   expect(wrapper).toMatchSnapshot();
 });
+
+test('async change', () => {
+  const wrapper = mount(Stepper, {
+    propsData: {
+      value: 1,
+      asyncChange: true
+    }
+  });
+
+  const plus = wrapper.find('.van-stepper__plus');
+  plus.trigger('click');
+
+  expect(wrapper.emitted('input')[0][0]).toEqual(2);
+  expect(wrapper.emitted('change')[0][0]).toEqual(2);
+
+  const input = wrapper.find('input');
+  input.element.value = '3';
+  input.trigger('input');
+
+  expect(wrapper.emitted('input')[1][0]).toEqual(3);
+  expect(wrapper.emitted('change')[1][0]).toEqual(3);
+});
+
+test('min value is 0', () => {
+  const wrapper = mount(Stepper, {
+    propsData: {
+      value: 1,
+      min: 0
+    }
+  });
+
+  const input = wrapper.find('input');
+  input.element.value = '';
+  input.trigger('input');
+  input.trigger('blur');
+
+  expect(wrapper.emitted('input')[0][0]).toEqual(0);
+});