message: docs(Form): add Picker demo
diff: @@ -195,6 +195,49 @@ export default {
  };
  ```
  +### Field Type - Picker
  +
  +```html
  +<van-field
  + readonly
  + clickable
  + name="picker"
  + :value="value"
  + label="Picker"
  + placeholder="Picker"
  + @click="showPicker = true"
  +/>
  +<van-popup v-model="showPicker" position="bottom">
  + <van-picker
  + show-toolbar
  + :columns="columns"
  + @confirm="onConfirm"
  + @cancel="onCancel"
  + />
  +</van-popup>
  +```
  +
  +```js
  +export default {
  + data() {
  + return {
  + value: '',
  + columns: ['Delaware', 'Florida', 'Georqia', 'Indiana', 'Maine'],
  + showPicker: false,
  + };
  + },
  + methods: {
  + onConfirm(value) {
  + this.value = value;
  + this.showPicker = false;
  + },
  + onCancel() {
  + this.showPicker = false;
  + },
  + },
  +};
  +```
  +
  ## API
  ### Props
  