在前面, 我们使用了UIPickerView试验了几次, 与其他UI控件结合在一起使用的也有, 今天我们就把UIPickerView剥的更深入, 让我们更加好的掌握UIPickerVIew, 下面让我们来看看
1.在.h文件里遵守UIPickerView的代理方法和数据源方法
#import <UIKit/UIKit.h> @interface ViewController : UIViewController <UIPickerViewDataSource, UIPickerViewDelegate> @end
2.在.m文件里声明全局变量
@interface ViewController () { UIPickerView *_pickerView; NSArray *_arrayOne; NSArray *_arrayTwo; } @end
PS:这两个数组分别是要用来存放UIPickerView的左右两边选择器的内容.
3.实例化UIPickerView
#pragma mark - 添加UIPikerView - (void)myPikerView { // 1.实例化UIPickerView _pickerView = [[UIPickerView alloc] initWithFrame:CGRectMake(0, self.view.frame.size.height - 250, self.view.frame.size.width, 250)]; [_pickerView setBackgroundColor:[UIColor grayColor]]; // 2.设置UIPickerView的代理方法和数据源方法. [_pickerView setDelegate:self]; [_pickerView setDataSource:self]; // 3.设置是否显示内容 [_pickerView setShowsSelectionIndicator:YES]; // 4.把UIPickerView添加到self.view [self.view addSubview:_pickerView]; }
4.添加UIPickerView的数据源方法
// 返回UIPickerView有多少列 - (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView { return 2; } // 返回UIPickerView有多少行 - (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component { if (component == 0) { return _arrayOne.count; } else { return _arrayTwo.count; } }
5.添加UIPickerView的代理方法
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component { if (component == 0) { return _arrayOne[row]; } else { return _arrayTwo[row]; } } - (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component { NSLog(@"第一列选中的行数是 %ld,第二列选中的行数是 %ld", [pickerView selectedRowInComponent:0], [pickerView selectedRowInComponent:1]); NSInteger leftCol = [pickerView selectedRowInComponent:0]; NSInteger rightCol = [pickerView selectedRowInComponent:1]; NSLog(@"%@ ~~~ %@", _arrayOne[leftCol], _arrayTwo[rightCol]); }
6.定义数组的内容
- (void)myArray { _arrayOne = @[@"辰东", @"唐家三少"]; _arrayTwo = @[@"完美世界", @"天火大道", @"神墓"]; }
最终效果:
附件: UIPickerView的代理方法拓展
- (CGFloat)pickerView:(UIPickerView *)pickerView rowHeightForComponent:(NSInteger)component { return 100; } - (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view { UIView *views = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 20, 20)]; [views setBackgroundColor:[UIColor redColor]]; return views; }
效果:
好了, 这次我们就讲到这里, 下次我们继续~~