objective-c - UIPickerView 自定义 View 不可视化

Question

我有自定义 View :

#import <UIKit/UIKit.h>
@interface materialView : UIView {
    IBOutlet UIImageView * _img;
    IBOutlet UILabel * _title;
}
- (id)initWithTitle:(NSString*)pTitle image:(UIImage *)pImage;
@end

和

#import "materialView.h"
@implementation materialView
- (id)initWithTitle:(NSString*)pTitle image:(UIImage *)pImage {
    CGRect frame = CGRectMake(0, 0, 295, 38);
    self = [super initWithFrame:frame];
    if (self) {
        [_img setImage:pImage];
        [_title setText:pTitle];
    }
return self;
}
@end

然后我将此 View 添加到我的 UIPickerView 中:

- (id)init {
    self=[super init];
    if (self) {
        materialView * pl = [[materialView alloc] initWithTitle:@"Plastic" image:[UIImage imageNamed:@"aaa.jpeg"]];
        materialView * gl = [[materialView alloc] initWithTitle:@"Glass" image:[UIImage     imageNamed:@"bbb.jpeg"]];
        _loadedItems = [[NSArray arrayWithObjects:pl, gl, nil] retain];
    } 
return self;
}
...

pickerView.dataSource = self;
pickerView.delegate = self;
...

- (UIView *)pickerView:(UIPickerView *)pickerView viewForRow:(NSInteger)row forComponent:(NSInteger)component reusingView:(UIView *)view {
    return [_loadedItems objectAtIndex:row];
}

问题是，我的行为很奇怪。我的 View 未显示在选取器 View 中。有谁可以帮助我吗？

Answer 1

首先，在您的:

- (UIView *)pickerView:(UIPickerView *)pickerView
            viewForRow:(NSInteger)row
          forComponent:(NSInteger)component
           reusingView:(UIView *)view

测试 _loadedItews 和通过 objectAtIndex: 返回的对象不是 nil？如果没有更多上下文，您的代码看起来很合理。

还将自定义 View 的 userInteractionEnabled 属性设置为 NO。似乎如果将其设置为 YES，则自定义 View 会拦截触摸，并且选择器无法滚动到点击的行。