UIPicker作为Subview

Question

我正在尝试添加UIPicker作为子视图，但无法弄明白。我已经向我的nib（NewWorkoutViewController.xib）添加了第二个带有UIPickerview的UIView控件。我的代码如下：

-(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)thePickerView
{
    return 1;
}


-(NSInteger)pickerView:(UIPickerView *)thePickerView numberOfRowsInComponent:(NSInteger)component
{
    return [list count];
}


-(NSString *)pickerView:(UIPickerView *)thePickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component
{
    return [list objectAtIndex:row];
}


-(void)pickerView:(UIPickerView *)thePickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component
{
    NSLog(@"Selected item: %@ index of selected item: %i", [list objectAtIndex:row], row);
}

-(void)viewDidLoad 
{
    [super viewDidLoad];
    counterInt = 0;

    list = [[NSMutableArray alloc] init];
    [list addObject:@"red"];
    [list addObject:@"blue"];
    [list addObject:@"yellow"];
    [list addObject:@"pink"];
}   

-(IBAction)routePicker
{   
    UIView *myView = [[UIView alloc] initWithFrame:CGRectMake(0, 480, 320, 216)];
    UIPickerView *thePickerView = [[UIPickerView alloc] initWithFrame:CGRectMake(0,0,320,216)];
    [myView addSubview:thePickerView];
    [self.view.superview addSubview:myView];  
}

我的子视图没有按预期弹出。

Answer 1

目前尚不清楚为什么你在代码中添加了选择器如果你已经在IB中添加了...关于你发布的代码，尝试将选择器添加到控制器的视图，而不是超级视图（并且不要忘记设置其代表）：

-(IBAction)routePicker
{   
    UIView *myView = [[UIView alloc] initWithFrame:CGRectMake(0, 480, 320, 216)];
    UIPickerView *thePickerView = [[UIPickerView alloc] initWithFrame:CGRectMake(0,0,320,216)];
    thePickerView.delegate = self;
    [myView addSubview:thePickerView];
    [self.view addSubview:myView];  
}

修改：使用可能位于可见区域之外的帧（框架的原点y坐标为480）初始化myView实例，尝试将其设置为0：

// Bad
UIView *myView = [[UIView alloc] initWithFrame:CGRectMake(0, 480, 320, 216)];
// Good?
UIView *myView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 216)]; 

Answer 2

从Apple

查看此示例

Date Cell Picker