ios开发-inputView和inputAccessoryView

说明

在UITextField和UITextField中能查到这两个属性

@property (readwrite, retain) UIView *inputView;

@property (readwrite, retain) UIView *inputAccessoryView;

在UITextField或者UITextField成为默认响应的时候，会弹出系统键盘。如果对这两个控件的inputView属性设置了自定义的view，在其成为第一响应的时候系统键盘将不再弹出，取而代之的是赋值给inputView的那个view。inputAccessoryView是键盘的辅助视图，即键盘上面那部分。同样当对inputAccessoryView设置了自定义view时，键盘弹出的同时，该view会作为辅助视图出现在键盘的上面，和键盘一起弹出。通常会使用pickerView作为自定义的弹出视图，这里为了简单起见，用一个普通的view演示：

基础代码演示

#import "ViewController.h"
#define SCREEN_BOUNDS [UIScreen mainScreen].bounds

@interface ViewController ()

@property (nonatomic, strong) UITextField *textField;
@property (nonatomic, strong) UIView *customInputView;  
@property (nonatomic, strong) UIToolbar *customAccessoryView;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    [self loadBaseUI];
}

- (void)loadBaseUI{
    [self.view addSubview:self.textField];
}

- (UITextField *)textField{
    if (!_textField) {
        _textField = [[UITextField alloc]initWithFrame:CGRectMake(50, 100, SCREEN_BOUNDS.size.width - 100, 30)];
        _textField.layer.borderWidth = 1.0;
        _textField.layer.borderColor = [UIColor lightGrayColor].CGColor;
        _textField.layer.cornerRadius = 4.0;
        _textField.placeholder = @"测试";
        _textField.inputView = self.customInputView;
        _textField.inputAccessoryView = self.customAccessoryView;
    }
    return _textField;
}

- (UIView *)customInputView{
    if (!_customInputView) {
        _customInputView = [[UIView alloc]initWithFrame:CGRectMake(0, 0, SCREEN_BOUNDS.size.width, 220)];
        _customInputView.backgroundColor = [UIColor lightGrayColor];
        UILabel *label = [[UILabel alloc]initWithFrame:CGRectMake(0, 100, SCREEN_BOUNDS.size.width, 40)];
        label.textAlignment = NSTextAlignmentCenter;
        label.text = @"自定义inputView";
        [_customInputView addSubview:label];
    }
    return _customInputView;
}

- (UIToolbar *)customAccessoryView{
    if (!_customAccessoryView) {
        _customAccessoryView = [[UIToolbar alloc]initWithFrame:(CGRect){0,0,SCREEN_BOUNDS.size.width,40}];
        _customAccessoryView.barTintColor = [UIColor orangeColor];
        UIBarButtonItem *space = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil];
        UIBarButtonItem *finish = [[UIBarButtonItem alloc]initWithTitle:@"完成" style:UIBarButtonItemStyleDone target:self action:@selector(done)];
        [_customAccessoryView setItems:@[space,space,finish]];
    }
    return _customAccessoryView;
}

- (void)done{
    [self.textField resignFirstResponder];
}

@end

点击textField后的显示效果

对其他控件设置inputView和inputAccessoryView

除了UITextField和UITextField，有事我们可能想让别的控件实现类似效果，比如点击一个按钮、选中某个cell的时候弹出键盘，但是对于UITextField和UITextField以外的控件，inputView和inputAccessoryView是只读的

@property (nonatomic, readonly, retain) UIView *inputView

@property (nonatomic, readonly, retain) UIView *inputAccessoryView

因此如果要使用控件这两个属性，就要创建该控件的子视图，然后重新申明inputView和inputAccessoryView为readwrite的，并重写它们的get方法，这样在UITableViewCell成为第一响应的时候会自动弹出inputView和inputAccessoryView。以UITableView演示：

代码示例

//MyTableViewCell.h

#import <UIKit/UIKit.h>
#define SCREEN_BOUNDS [UIScreen mainScreen].bounds

@interface MyTableViewCell : UITableViewCell

//属性申明为可读写
@property (nonatomic, strong, readwrite) UIView *inputView;

@property (nonatomic, strong, readwrite) UIToolbar *inputAccessoryView;

@end

//  MyTableViewCell.m

#import "MyTableViewCell.h"

@implementation MyTableViewCell

//重写get方法
- (UIView *)inputView{
    if (!_inputView) {
        _inputView = [[UIView alloc]initWithFrame:CGRectMake(0, 0, SCREEN_BOUNDS.size.width, 220)];
        _inputView.backgroundColor = [UIColor lightGrayColor];
        UILabel *label = [[UILabel alloc]initWithFrame:CGRectMake(0, 100, SCREEN_BOUNDS.size.width, 40)];
        label.textAlignment = NSTextAlignmentCenter;
        label.text = @"自定义inputView";
        [_inputView addSubview:label];
    }
    return _inputView;
}

- (UIToolbar *)inputAccessoryView{
    if (!_inputAccessoryView) {
        _inputAccessoryView = [[UIToolbar alloc]initWithFrame:(CGRect){0,0,SCREEN_BOUNDS.size.width,40}];
        _inputAccessoryView.barTintColor = [UIColor orangeColor];
        UIBarButtonItem *space = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemFlexibleSpace target:nil action:nil];
        UIBarButtonItem *finish = [[UIBarButtonItem alloc]initWithTitle:@"完成" style:UIBarButtonItemStyleDone target:self action:@selector(done)];
        [_inputAccessoryView setItems:@[space,space,finish]];
    }
    return _inputAccessoryView;
}

- (void)done{
    [self resignFirstResponder];
}

@end

在主视图控制器中创建一个tableView发现这样之后点击cell发现不会弹出inputView，最后查阅官方文档发现需要在子类中重写canBecomeFirstResponder方法：

在子类.m文件中添加

- (BOOL)canBecomeFirstResponder{
    return YES;
}

发现还是不行，最后手动becomeFirstResponder，终于实现了。PS原来选中都还不算是成为第一响应，坑爹啊！

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{
    MyTableViewCell *cell = (MyTableViewCell *)[tableView cellForRowAtIndexPath:indexPath];
    [cell becomeFirstResponder];
}

效果图