swift UIPickView

/* swift 3.0    UIPickView的使用
        
*/
        
        let pickView =
UIPickerView()
        pickView.dataSource =
self
        pickView.delegate =
self
        pickView.showsSelectionIndicator =
true
        
        /* 设置pickerView默认选中 
         
            Component表示列,
下标从0开始
            row表示行,
下标从0开始
            
         
         */
        pickView.selectRow(0, inComponent:
0, animated: true)
        pickView.selectRow(0, inComponent:
1, animated: true)
        pickView.selectRow(0, inComponent:
2, animated: true)
        
        view.addSubview(pickView)
        
        
        /* 获取默认的选中信息 */
        print(pickView.selectedRow(inComponent:
0))
        print(pickView.selectedRow(inComponent:
1))
        print(pickView.selectedRow(inComponent:
2))
        
        
        
    }
    

}

extension UIViewController :UIPickerViewDataSource,UIPickerViewDelegate
{

    /* 设置选择框的列数为3 */
    public
func numberOfComponents(in pickerView:
UIPickerView) -> Int{
        
        return
3;
    }
    
    /* 设置行数为9 */
    public
func pickerView(_ pickerView:
UIPickerView, numberOfRowsInComponent component:
Int) -> Int{
    
        return
9;
    }

/* 使用系统的view时，
返回要显示的文字 */
    public
func pickerView(_ pickerView:
UIPickerView, titleForRow row:
Int, forComponent component: Int) ->
String? {
    
        return
String(row)+"-"+String(component)
    }
    
    
/* 自定义view */
//    public func pickerView(_ pickerView: UIPickerView, viewForRow row: Int, forComponent component: Int, reusing view: UIView?) -> UIView {
//        
//        
//        let view = UILabel()
//        view.backgroundColor = UIColor.orange
//        view.text = "12345"
//        
//        return  view
//    }

    
    /* 检查响应选项的选择状态 */
    public
func pickerView(_ pickerView:
UIPickerView, didSelectRow row:
Int, inComponent component: Int) {
        
        print(pickerView.selectedRow(inComponent: component))
    }
}