UI_自定义视图_code-优快云博客

本文介绍如何使用 Objective-C 自定义 UITextField 控件，并将其应用于 iOS 应用中。通过继承 UIView 创建 LTView 类，实现了带有标题和占位符的文本输入框，并支持密码输入。

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Day 03 of UI

LTView（自定义视图）

AppDelegate.m

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    // Override point for customization after application launch.
    // 设置window
    self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
    self.window.backgroundColor = [UIColor whiteColor];
    [self.window makeKeyAndVisible];
    [self.window release];
    
    // 创建一个LTView对象，添加到Window上
    LTView *useNameLTView = [[LTView alloc] initWithFrame:CGRectMake(50, 50, CGRectGetWidth([UIScreen mainScreen].bounds) - 100, 35)];
    useNameLTView.backgroundColor = [UIColor cyanColor];
    [self.window addSubview:useNameLTView];
    useNameLTView.title = @"用户名";
    useNameLTView.placeHolder = @"请输入用户名";
    [useNameLTView release];
    
    LTView *passwordLTView = [[LTView alloc] initWithFrame:CGRectMake(50, 150, CGRectGetWidth([UIScreen mainScreen].bounds) - 100, 35) title:@"密码" placeHolder:@"请输入密码"];
    passwordLTView.backgroundColor = [UIColor cyanColor];
    passwordLTView.isSecureText = 1;
    passwordLTView.delegate = self;
    [self.window addSubview:passwordLTView];
    [passwordLTView release];
    
    return YES;
}

- (BOOL)textFieldShouldReturn:(UITextField *)textField
{
    NSLog(@"22");
    [textField resignFirstResponder];
    return YES;
}

LTView.h

@interface LTView : UIView
#pragma mark - 声明属性

@property (nonatomic, copy) NSString *title;
@property (nonatomic, copy) NSString *placeHolder;

@property (nonatomic, copy) NSString *text;
@property (nonatomic, assign) id <UITextFieldDelegate>delegate;
@property (nonatomic, assign) BOOL isSecureText;

#pragma mark - 声明自定义初始化方法
- (instancetype)initWithFrame:(CGRect)frame
                        title:(NSString *)title
                  placeHolder:(NSString *)placeHolder;
@end

LTView.m

@interface LTView()
@property (nonatomic, retain) UILabel *label;
@property (nonatomic, retain) UITextField *textfield;

@end

@implementation LTView


@synthesize text = _text;
#pragma mark - 重写dealloc方法
- (void)dealloc
{
    [_label release];
    [_textfield release];
    
    [super dealloc];
}

#pragma mark - 重写初始化方法
- (instancetype)initWithFrame:(CGRect)frame
{
    if (self = [super initWithFrame:frame]) {
        // 1. 创建左侧的Label
        self.label = [[[UILabel alloc] initWithFrame:CGRectMake(0, 0, CGRectGetWidth(frame) / 3, CGRectGetHeight(frame))] autorelease];
  
        self.label.backgroundColor = [UIColor redColor];
        [self addSubview:_label];
        
        // 2. 创建右侧的TextField
        self.textfield = [[[UITextField alloc] initWithFrame:CGRectMake(CGRectGetWidth(frame) / 3, 0, CGRectGetWidth(frame) * 2 / 3, CGRectGetHeight(frame))] autorelease];
  
        [self addSubview:_textfield];
        
    }
    return self;
}

#pragma mark - 重写title的set方法，把外界的值传过来
- (void)setTitle:(NSString *)title
{
    if (_title != title) {
        [_title release];
        _title = [title copy];
        
        _label.text = title;
    }
}


- (void)setPlaceHolder:(NSString *)placeHolder
{
    if (_placeHolder != placeHolder) {
        [_placeHolder release];
        _placeHolder = [placeHolder copy];
        
        _textfield.placeholder = _placeHolder;
    }
}

#pragma mark - 实现自定义初始化方法
- (instancetype)initWithFrame:(CGRect)frame
                        title:(NSString *)title
                  placeHolder:(NSString *)placeHolder
{
    self = [self initWithFrame:frame];
    if (self) {
        _label.text = title;
        _textfield.placeholder = placeHolder;
    }
    return self;
}

-(void)setDelegate:(id<UITextFieldDelegate>)delegate
{
    _textfield.delegate = delegate;
}

- (void)setText:(NSString *)text
{
    if (_text != text) {
        [_text release];
        _text = [text copy];
        _textfield.text = text;
    }
}

- (NSString *)text
{
    return _textfield.text;
}

- (void)setIsSecureText:(BOOL)isSecureText
{
    _textfield.secureTextEntry = isSecureText;
}

@end