UIPickerView的简单封装

在iOS实际项目中，经常会出现界面中多个地方需要使用UIPickerView,如果在每个需要用到的地方都创建一个UIPickerView不仅更耗性能，而且还会让你的代码变得更加杂乱、冗余，因此我在这里向大家介绍一下我对UIPickerView的一些简单封装。

所需属性

/** pickerView*/
@property (nonatomic, strong) UIPickerView pickerView;
/* pickerView背景*/
@property (nonatomic, strong) UIView pickerBackGroundView;
/* 背景*/
@property (nonatomic, strong) UIView backGroundView;
/* 确认按钮*/
@property (nonatomic, strong) UIButton sureButton;
/* 取消按钮*/
@property (nonatomic, strong) UIButton cancelButton;
/* 单列pickerView*/
@property (nonatomic, strong) NSMutableArray slDataArray;
/* 双列pickerView*/
@property (nonatomic, strong) NSMutableArray *mulDataArray;

如果只需要一列的话，只需要传入一个数据数组:slDataArray,如果需要两行，则两个数组都需要赋值。

实现UIPickerView代理方法

-(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView{
     if (self.mulDataArray.count == 0) {
        return 1;
    }else {
        return 2;
        }
}
-(NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component{
    if (component == 0) {
        return self.slDataArray.count;
        }else {
        return self.mulDataArray.count;
    }
}
-(NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:
(NSInteger)component{
    if (component == 0) {
        return self.slDataArray[row];
    }else {
    return self.mulDataArray[row];
    }
}

这里根据两个数组来初始化pickerView的内容，即判断第二个数组(mulDataArray)是否有数据，有数据的话代表加载两列的pickerView，否则加载一列。

功能实现

-(void)pickerViewSelectRow:(NSInteger)row {
    self.selectRow = row;
    [self.pickerView selectRow:row inComponent:0 animated:NO];
}
-(void)pickerViewSelectRow:(NSInteger)row lastRow:(NSInteger)lastRow{
    [self.pickerView selectRow:row inComponent:0 animated:NO];
    [self.pickerView selectRow:lastRow inComponent:1 animated:NO];
}

第一个方法是只有一列的pickerView初始化是让其选中哪行，第二个则是两列的选择方法。

-(void)showOrHidePickerView:(BOOL)isShow{
    if (isShow) {
        if (self.isPickerShow == NO) {
            [self addSubview:self.backGroundView];
            [self addSubview:self.pickerBackGroundView];
            [UIView animateWithDuration:0.3 animations:^{
                 self.backGroundView.alpha = 0.5;
                 self.pickerBackGroundView.frame = CGRectMake(0, SCREEN_HEIGHT -220, SCREEN_WIDTH, 220);
            } completion:^(BOOL finished) {
          self.isPickerShow = YES;
            }];
        }
    }else {
        if (self.isPickerShow) {
            [UIView animateWithDuration:0.3 animations:^{
            self.backGroundView.alpha = 0.0;
            self.pickerBackGroundView.frame = CGRectMake(0, SCREEN_HEIGHT, SCREEN_WIDTH, 220);
        } completion:^(BOOL finished) {
            [self.backGroundView removeFromSuperview];
            [self.pickerBackGroundView removeFromSuperview];
            self.isPickerShow = NO;
        }];
        }
    }
}

这个方法是显示或者隐藏pickerView,通过动画的方式，背景慢慢变黑或者透明，pickerView从下往上出现或者从上往下消失。

-(void)pickerViewReloadData{
    [self.pickerView reloadAllComponents];
}

刷新pickerView数据，加载另一个pickerView时，调用该方法刷新。