ios - 无法在选择器 View 中设置组件宽度

Question

我试图在选择器 View 中设置两个组件的宽度。它们的宽度相等，我想加宽一点。为此，我使用了

• (CGFloat)pickerView:(UIPickerView *)pickerView widthForComponent:(NSInteger)组件

方法。

我的问题是，设置方法后，我只得到一个组件而不是两个。我检查了一下是不是我的方法写错了，但是没发现有什么问题。

知道出了什么问题吗？

这是代码:

#import "BIDDependentComponentPickerViewController.h"

@implementation BIDDependentComponentPickerViewController

@synthesize picker;
@synthesize stateZips;
@synthesize states;
@synthesize zips;


- (IBAction)buttonPressed:(id)sender
{
    NSInteger stateRow = [picker selectedRowInComponent:kStateComponent];
    NSInteger zipRow = [picker selectedRowInComponent:kZipComponent];

    NSString *state = [self.states objectAtIndex:stateRow];
    NSString *zip = [self.zips objectAtIndex:zipRow];

    NSString *title= [[NSString alloc] initWithFormat:@"You selected zip code %@.", zip];
    NSString *message = [[NSString alloc] initWithFormat:@"@% is in @%", zip, state];

    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:title 
                                                    message:message 
                                                   delegate:nil 
                                          cancelButtonTitle:@"OK" 
                                          otherButtonTitles:nil];
    [alert show];
}
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)didReceiveMemoryWarning
{
    // Releases the view if it doesn't have a superview.
    [super didReceiveMemoryWarning];

    // Release any cached data, images, etc that aren't in use.
}

#pragma mark - View lifecycle

- (void)viewDidLoad
{
    [super viewDidLoad];
    // Do any additional setup after loading the view from its nib.
    NSBundle *bundle = [NSBundle mainBundle];
    NSURL *plistURL = [bundle URLForResource:@"statedictionary" withExtension:@"plist"];

    NSDictionary *dictionary = [NSDictionary dictionaryWithContentsOfURL:plistURL];
    self.stateZips = dictionary;

    NSArray *components = [self.stateZips allKeys];
    NSArray *sorted = [components sortedArrayUsingSelector:@selector(compare:)];
    self.states = sorted;

    NSString *selectedState = [self.states objectAtIndex:0];
    NSArray *array = [stateZips objectForKey:selectedState];
}

- (void)viewDidUnload
{
    [super viewDidUnload];
    // Release any retained subviews of the main view.
    // e.g. self.myOutlet = nil;
    self.picker = nil;
    self.stateZips = nil;
    self.states = nil;
    self.zips = nil;
}

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
    // Return YES for supported orientations
    return (interfaceOrientation == UIInterfaceOrientationPortrait);
}

#pragma mark
#pragma mark Picker Data Source Methods

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

- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component
{
    if (component == kStateComponent) {
        return [self.states count];
        return [self.zips count];
    }
}

#pragma mark Picker Delegate Methods
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component
{
    if(component == kStateComponent)
        return [self.states objectAtIndex:row];
    return [self.zips objectAtIndex:row];
}

- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {
if (component == kStateComponent)
    {
    NSString *selectedState = [self.states objectAtIndex:row];
    NSArray *array = [stateZips objectForKey:selectedState];

    self.zips = array;
    [picker selectRow:0 inComponent:kZipComponent animated:YES];
    [picker reloadComponent:kZipComponent];
    }
}

- (CGFloat)pickerView:(UIPickerView *)pickerView widthForComponent:(NSInteger)component
{
    if (component == kZipComponent) {
        return 90;
        return 200;
    }
}


@end

Answer 1

行:

return 200;

从未达到。它应该位于 IF 语句之外，如下所示:

if (component == kZipComponent) {
    return 90.0;
}
return 200.0;

否则，您的方法不会为除 kZipComponent 之外的任何组件返回值(因此其他组件的宽度为 0)。