062在文本输入框中设置一个清空按钮

效果如下：

ViewController.h

1 #import <UIKit/UIKit.h>
2
3 @interface ViewController : UIViewController<UITextFieldDelegate>
4 @property (strong, nonatomic) NSMutableArray *mArrTextField;
5
6 @end

ViewController.m

 1 #import "ViewController.h"
 2
 3 @interface ViewController ()
 4 - (void)layoutUI;
 5 - (UITextField *)newTextField:(UITextFieldViewMode)clearButtonMode frame:(CGRect)rect;
 6 - (void)hideKeyboard:(id)sender;
 7 @end
 8
 9 @implementation ViewController
10 - (void)viewDidLoad {
11     [super viewDidLoad];
12
13     [self layoutUI];
14
15     UITapGestureRecognizer *tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(hideKeyboard:)];
16     [self.view addGestureRecognizer:tapGestureRecognizer];
17 }
18
19 - (void)didReceiveMemoryWarning {
20     [super didReceiveMemoryWarning];
21     // Dispose of any resources that can be recreated.
22 }
23
24 #pragma mark - Private Methods
25 /**
26  *  隐藏键盘
27  *
28  *  @param sender 事件触发者
29  */
30 - (void)hideKeyboard:(id)sender {
31     NSLog(@"Tap Gesture Recognizer，去掉某些控件作为第一响应器");
32     for (UITextField *txtF in _mArrTextField) {
33         [txtF resignFirstResponder];
34     }
35 }
36
37 - (void)layoutUI {
38     _mArrTextField = [[NSMutableArray alloc] initWithCapacity:4];
39
40     CGRect rectTemp = CGRectMake(20, 40, 320, 40);
41     UITextField *txtFTemp = [self newTextField:UITextFieldViewModeNever frame:rectTemp];
42     [self.view addSubview:txtFTemp];
43     [_mArrTextField addObject:txtFTemp];
44
45     rectTemp.origin.y += 50;
46     txtFTemp = [self newTextField:UITextFieldViewModeWhileEditing frame:rectTemp];
47     [self.view addSubview:txtFTemp];
48     [_mArrTextField addObject:txtFTemp];
49
50     rectTemp.origin.y += 50;
51     txtFTemp = [self newTextField:UITextFieldViewModeUnlessEditing frame:rectTemp];
52     [self.view addSubview:txtFTemp];
53     [_mArrTextField addObject:txtFTemp];
54
55     rectTemp.origin.y += 50;
56     txtFTemp = [self newTextField:UITextFieldViewModeAlways frame:rectTemp];
57     [self.view addSubview:txtFTemp];
58     [_mArrTextField addObject:txtFTemp];
59 }
60
61 - (UITextField *)newTextField:(UITextFieldViewMode)clearButtonMode frame:(CGRect)rect {
62     UITextField *txtFMessage = [[UITextField alloc] initWithFrame:rect];
63     txtFMessage.textAlignment = NSTextAlignmentLeft;
64     txtFMessage.textColor = [UIColor colorWithRed:0.433 green:0.829 blue:1.000 alpha:1.000];
65     txtFMessage.borderStyle = UITextBorderStyleRoundedRect;
66
67     txtFMessage.delegate = self;
68     txtFMessage.clearButtonMode = clearButtonMode;
69     switch (clearButtonMode) {
70         case UITextFieldViewModeNever:
71             txtFMessage.text = @"UITextFieldViewModeNever"; //不显示清空按钮；默认值
72             break;
73         case UITextFieldViewModeWhileEditing:
74             txtFMessage.text = @"UITextFieldViewModeWhileEditing";  //文本内容不为空时，且在编辑状态（即获得焦点）时显示清空按钮
75             break;
76         case UITextFieldViewModeUnlessEditing:
77             txtFMessage.text = @"UITextFieldViewModeUnlessEditing";  //文本内容不为空时，且不在编辑状态（即失去焦点）时显示清空按钮
78             break;
79         case UITextFieldViewModeAlways:
80             txtFMessage.text = @"UITextFieldViewModeAlways"; //文本内容不为空时，获得焦点与失去焦点都显示清空按钮
81             break;
82     }
83     return txtFMessage;
84 }
85
86 #pragma mark - TextField
87 - (BOOL)textFieldShouldClear:(UITextField *)textField {
88     NSLog(@"textFieldShouldClear: %@", textField.text); //记录清空按钮触发清空的文本内容；例如：UITextFieldViewModeWhileEditing
89     return YES;
90 }
91
92 @end