ion-picker设定默认值

  async showBasicPicker() {
    const opts: PickerOptions = {
      buttons: [
        {
          text: 'Cancel',
          role: 'cancel'
        },
        {
          text: 'Done'
        }
      ],
      columns: [
        {
          name: 'framework',
          selectedIndex: 2,
          options: [
            { text: 'Angular', value: 'A' },
            { text: 'Vue', value: 'B' },
            { text: 'React', value: 'C' }
          ]
        }
      ]
    };
    const picker = await this.pickerCtrl.create(opts);
    picker.present();
  }