UIPickerView开发一般选择区域或者分级数据的时候会使用到,类似于前端中用到树状结构,不过PC上一般都是从上到下的分级,使用UIPickView是从左到右实现,可以动态的设置UIPickView中中行列数据,将结果显示在文本输入框里,简单的定义一下数据源。通过声明协议捕获事件,展示结果,比较简单,进入正题.
页面布局
页面布局比较简单,一个UIPickerView,一个文本框:
头文件中的声明,实现了UIPickerViewDelegate,UIPickerViewDataSource协议:
@interface ViewController : UIViewController <UIPickerViewDelegate,UIPickerViewDataSource> @property (weak, nonatomic) IBOutlet UIPickerView *pickView; @property (weak, nonatomic) IBOutlet UITextField *areaTextField; @end
Demo实现
定义存储数据的数组:
@interface ViewController () { NSArray *areaArr; NSMutableArray *teamArr; }
初始化数据:
- (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. areaArr=@[@"西南区",@"中央区",@"东南区",@"大西洋区",@"西北区",@"太平洋区"]; teamArr=[[NSMutableArray alloc] init]; [teamArr addObject:@[@"马刺",@"灰熊",@"小牛",@"火箭",@"鹈鹕"]]; [teamArr addObject:@[@"活塞",@"步行者",@"骑士",@"公牛",@"雄鹿"]]; [teamArr addObject:@[@"热火",@"魔术",@"老鹰",@"奇才",@"黄蜂"]]; [teamArr addObject:@[@"凯尔特人",@"76人",@"尼克斯",@"篮网",@"猛龙"]]; [teamArr addObject:@[@"森林狼",@"掘金",@"爵士",@"开拓者",@"雷霆"]]; [teamArr addObject:@[@"国王",@"太阳",@"湖人",@"快船",@"勇士"]]; }
设置PickerView的列数:
- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView{ return 2; }
返回行数:
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component{ //判断列 if (component==0) { return [areaArr count]; }else{ //判断0列中当前的行号 NSInteger currentRow=[pickerView selectedRowInComponent:0]; return [teamArr[currentRow] count]; } }
设置每行每列中的数据:
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component{ if (component==0) { //o列从区域数组中选择 return areaArr[row]; }else{ //根据0列中选择的行号 NSInteger currentRow=[pickerView selectedRowInComponent:0]; return teamArr[currentRow][row]; } }
选择完成之后的事件:
- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component{ [pickerView reloadComponent:1]; NSInteger areaRow=[pickerView selectedRowInComponent:0]; NSInteger teamRow=[pickerView selectedRowInComponent:1]; [_areaTextField setText:[NSString stringWithFormat:@"%@-%@",areaArr[areaRow],teamArr[areaRow][teamRow]]]; }
具体效果如下: