# List组件如何设置多列

以列模式为例(listDirection为Axis.Vertical):lanes用于决定List组件在交叉轴方向上的列数。参考代码如下：

```
@Entry
@Component
struct ListLanesExample {
  @State arr: string[] = ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '10', '11', '12', '13', '14', '15', '16', '17', '18', '19'];
  @State alignListItem: ListItemAlign = ListItemAlign.Start;

  build() {
    Column() {
      List({ space: 20, initialIndex: 0 }) {
        ForEach(this.arr, (item: string) => {
          ListItem() {
            Text('' + item)
              .width('100%')
              .height(100)
              .fontSize(16)
              .textAlign(TextAlign.Center)
              .borderRadius(10)
              .backgroundColor(0xFFFFFF)
          }
          .border({ width: 2, color: Color.Green })
        }, (item: string) => item)
      }
      .height(300)
      .width('90%')
      .border({ width: 3, color: Color.Red })
      .lanes({ minLength: 40, maxLength: 40 })
      .alignListItem(this.alignListItem)

      Button('Click to change alignListItem:' + this.alignListItem).onClick(() => {
        if (this.alignListItem == ListItemAlign.Start) {
          this.alignListItem = ListItemAlign.Center;
        } else if (this.alignListItem == ListItemAlign.Center) {
          this.alignListItem = ListItemAlign.End;
        } else {
          this.alignListItem = ListItemAlign.Start;
        }
      })
    }.width('100%').height('100%').backgroundColor(0xDCDCDC).padding({ top: 5 })
  }
}
```