加载我的pickerview时得到一个“？”

问题描述

| 我在这里搜索，但没有看到类似此错误的信息。 我正在尝试在ViewDidLoad上填充我的pickerview，但是当我运行程序时，pickerView只是填充了\“？\”而不是我的字符串...这是怎么回事？提前致谢。

- (void)viewDidLoad {
    [super viewDidLoad];

    activities = [[NSArray alloc] initWithObjects:@\"sleeping\",@\"eating\",@\"working\",@\"thinking\",@\"crying\",@\"begging\",@\"leaving\",@\"shopping\",@\"hello worlding\",nil];

    feelings = [[NSArray alloc] initWithObjects:@\"awsome\",@\"sad\",@\"happy\",@\"ambivalent\",@\"nauseous\",@\"psyched\",@\"confused\",@\"hopeful\",@\"anxious\",nil];

}

    

解决方法

        您需要实现

UIPickerViewDelegate

和

UIPickerViewDataSource

协议：

- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView
{
    return 2;
}

- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component
{
    if (component == 0)
        return [activities count];
    else
        return [feelings count];
}

- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component
{
    if (component == 0)
        return [activities objectAtIndex:row];
    else
        return [feelings objectAtIndex:row];
}