Question

如何在此方法中获取文本字段来调用textfieldshouldreturn？我猜它不起作用，因为UIView没有委托属性，但我不知道如何制作一个UIView，我在一个符合协议的方法中创建。我见过几篇关于代表团的帖子，但我尝试过的一切都没有用。我确信这很简单。提前谢谢。

- (void) launchCreateNewListActionSheet{
    self.listActionSheet= [[UIActionSheet alloc] initWithTitle:@"Create A New List"
                                                  delegate:self
                                         cancelButtonTitle:nil
                                    destructiveButtonTitle:nil
                                         otherButtonTitles:nil];

    UIView *addToNewList = [[UIView alloc] initWithFrame:CGRectMake(0, 44, 320, 464)];
    addToNewList.backgroundColor = [UIColor whiteColor];

    UILabel *addToNewListLabel = [[UILabel alloc] initWithFrame:CGRectMake(10, 23, 100, 20)];
    addToNewListLabel.text = @"List Name: ";

    UITextField *enterNewListName = [[UITextField alloc] initWithFrame:CGRectMake(100, 20, 180, 30)];
    enterNewListName.layer.borderWidth = 1;
    enterNewListName.layer.borderColor = [[UIColor blackColor] CGColor];
    enterNewListName.delegate = self;

    [addToNewList addSubview:addToNewListLabel];
    [addToNewList addSubview:enterNewListName];


    UIBarButtonItem *doneBtn = [[UIBarButtonItem alloc]     initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(addToExistingList)];

    UIBarButtonItem *cancelBtn = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemCancel target:self action:@selector(cancelListPicker)];

    UIBarButtonItem *fixedCenter = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemFixedSpace target:nil action:nil];
fixedCenter.width = 180.0f;

    UIToolbar* toolbar = [[UIToolbar alloc] initWithFrame:CGRectMake(0, 0, 320, 44)];
    toolbar.barStyle = UIBarStyleBlackOpaque;
    [toolbar sizeToFit];

    [toolbar setItems:@[cancelBtn, fixedCenter, doneBtn] animated:YES];

    [self.listActionSheet addSubview:toolbar];
    [self.listActionSheet addSubview:addToNewList];
    [self.listActionSheet showInView:self.view];
    [self.listActionSheet setBounds:CGRectMake(0,0,320, 464)];
}

这是我的.h文件。我已实现，因为它适用于其他方法中的文本字段。

#import <UIKit/UIKit.h>
#import <Foundation/Foundation.h>
#import "ZBarSDK.h"
#import "ProgressView.h"

@class ScannerViewController;

@protocol ScanViewDelegate <NSObject>;
@required
-(void)postURL:(NSURL*)url selectedAction:(NSString*)action;
@end

@interface ScannerViewController : UIViewController <ZBarReaderViewDelegate,        UITableViewDelegate, UITableViewDataSource, UITextFieldDelegate, UIWebViewDelegate,    UIPickerViewDelegate, UIActionSheetDelegate>

    id <ScanViewDelegate> delegate;
}
@property (weak, nonatomic) IBOutlet ZBarReaderView *readerView;
@property (weak, nonatomic) IBOutlet UITableView *scannerList;
@property (retain) id delegate;

@property (strong) NSMutableArray* barCodeArray;
@property (strong) NSMutableArray* quantityArray;
@property (strong) NSURL* url;
@property (strong) NSString* action;
@property NSString *listItems;
@property NSString *listItemNames;
@property NSArray *listItemNamesArray;
@property NSArray *hrefArray;
@property int pickerViewRow;
@property (strong) UIWebView *webView;
@property (strong) ProgressView* loading;
@property BOOL isLoading;
@property (strong) UITextField *enterNewListName;
@property (strong) UITextField *addToNewListDescription;
@property (strong) NSMutableArray *textFieldArray;

-(IBAction)sendToCart:(id)sender;
-(IBAction)sendToList:(id)sender;
-(void)startLoadingURL;
@end

这是textfieldshouldreturn方法：

-(BOOL)textFieldShouldReturn:(UITextField *)textField
{
    if([self.textFieldArray containsObject:textField])
    {
        NSUInteger index = [self.textFieldArray indexOfObject:textField];
        NSNumber *newQuantity = [NSNumber numberWithInteger:[textField.text integerValue]];
        [self.quantityArray replaceObjectAtIndex:index withObject:newQuantity];
        NSLog(@"Your new quantity is: %@", newQuantity);
    }
    [textField resignFirstResponder];
    return YES;
}

Answer 1

这里的关键点是Andres想在UIActionSheet上使用UiTextField。 UIActionSheet在点击时有一些不同的行为，实际上它阻止了UiTextField的健康使用被添加到动作表中。

请参阅此SO答案，其中发现使用自定义解决方案更好： keyboard in UIActionSheet does not type anything

基本上最好使用 ~~UIAlertView作为模态文本输入视图表单（please see this link）~~模仿UIActionSheet的自定义视图，以及更多自定义空间（例如github as a starting point ）但UIActionSheet也有一个解决方案。

为了将UITextField放置在视图层次结构中，UIActionSheet在显示UIActionSheet后显示UIActionSheet这个代码片段

    [self.listActionSheet addSubview:toolbar];
    // [self.listActionSheet addSubview:addToNewList];  // please comment-delete this line
    [self.listActionSheet showInView:self.view];
    [self.listActionSheet setBounds:CGRectMake(0,0,320, 464)];
    // this is the 2 new lines below
    UIWindow *appWindow = [UIApplication sharedApplication].keyWindow;
    [appWindow insertSubview:addToNewList aboveSubview:listActionSheet];  // you add custom view here

Answer 2

您是否已启用相应的课程与UITextFieldDelegate兼容？

请转到当前类的.h文件，并使其与UITextFieldDelegate兼容。

例如：如果您的ClassName是HomeController

我假设您收到类似的警告：

Assigning to id<UITextFieldDelegate> from incompatible type "HomeController"

<强>解决方案：

@interface HomeController : UIViewController <UITextFieldDelegate>
    // YOur Class Variable.
@end

Answer 3

首先，如果您的类不符合具有所需方法的协议，则会在将委托设置为类的行中生成警告。

Nwo，如果你想让自定义类成为UITextField的委托，你必须声明并实现所需的方法。在您的情况下，您必须执行以下操作：

在 YourCustomView.h

中

@interface YourCustomView : UIView (or other class) <UITextFieldDelegate> // this will show that this class conforms to UITextFieldDelegate protocol
//other methods or properties here
@end

在 YourCustomView.m

中

@implementation YourCustomView 

-(void)launchCreateNewListActionSheet {
   //some code here 
    UITextField *textField = //alloc init methd
    textField.delegate = self;
}

#pragma mark - UITextFieldDelegate //this is optional only if you want to structure the code
- (BOOL)textFieldShouldReturn:(UITextField *)textField { 
     //method called when the text field resign first responder
}

//您可以根据需要添加更多委托方法。 @end

Answer 4

您的UIView不需要委托属性。它只需要实现UITextField delegate methods。它们都是可选的，因此如果你不实现它们，编译器就不会抱怨。

您的代码看起来不错。但是要查看是否正确连接，请在UIView子类中实现textFieldDidBeginEditing:以生成日志，并在选择文本字段时查看日志是否出现。

- (void)textFieldDidBeginEditing:(UITextField *)textField
{
   NSLog(@"textFieldDidBeginEditing: %@ (delegate: %@)", textField, [textField delegate]);
}

如果工作正常，那么登录textFieldShouldReturn：等等。如果这不起作用，那么其他地方就出现了问题。您发布的代码在快速浏览时看起来不错。

TextFieldShoudReturn没有被调用

4 个答案: