回答

单列选择器

代码如下

<template>
	<view>
		<picker @change="bindPickerChange" :value="index" :range="array" range-key="name">
			<view style="padding: 20rpx;background-color: white;">{{ array[index].name }}</view>
		</picker>
	</view>
</template>
<script>
export default {
	data() {
		return {
			array: [{ name: '中国' }, { name: '美国' }, { name: '巴西' }, { name: '日本' }],
			index: 2,
		};
	},
	methods: {
		bindPickerChange: function(e) {
			this.index = e.detail.value;
		}
	}
};
</script>

代码如下：

<template>
	<view>
		<picker mode="multiSelector" @columnchange="bindMultiPickerColumnChange" :value="multiIndex" :range="multiArray">
			<view style="background-color: white;">
				{{ multiArray[0][multiIndex[0]] }}，
				{{ multiArray[1][multiIndex[1]] }}，
				{{ multiArray[2][multiIndex[2]] }}
			</view>
		</picker>
	</view>
</template>
<script>
export default {
	data() {
		return {
			multiArray: [['亚洲', '欧洲'], ['中国', '日本'], ['北京', '上海', '广州']],
			multiIndex: [0, 0, 0]
		};
	},
	methods: {
		bindMultiPickerColumnChange: function(e) {
			this.multiIndex[e.detail.column] = e.detail.value;
			switch (e.detail.column) {
				case 0: //拖动第1列
					switch (this.multiIndex[0]) {
						case 0:
							this.multiArray[1] = ['中国', '日本'];
							this.multiArray[2] = ['北京', '上海', '广州'];
							break;
						case 1:
							this.multiArray[1] = ['英国', '法国'];
							this.multiArray[2] = ['伦敦', '曼彻斯特'];
							break;
					}
					this.multiIndex.splice(1, 1, 0);
					this.multiIndex.splice(2, 1, 0);
					break;
				case 1: //拖动第2列
					switch (
						this.multiIndex[0] //判断第一列是什么
					) {
						case 0:
							switch (this.multiIndex[1]) {
								case 0:
									this.multiArray[2] = ['北京', '上海', '广州'];
									break;
								case 1:
									this.multiArray[2] = ['东京', '北海道'];
									break;
							}
							break;
						case 1:
							switch (this.multiIndex[1]) {
								case 0:
									this.multiArray[2] = ['伦敦', '曼彻斯特'];
									break;
								case 1:
									this.multiArray[2] = ['巴黎', '马赛'];
									break;
							}
							break;
					}
					this.multiIndex.splice(2, 1, 0);
					break;
			}
			this.$forceUpdate();
		}
	}
};
</script>