我想插入一个UITextField的文本。

这可能吗?


当前回答

我子类化UITextField来处理这个,它支持左,上,右和底部的插入,以及清除按钮的定位。

MRDInsetTextField.h

#import <UIKit/UIKit.h>

@interface MRDInsetTextField : UITextField

@property (nonatomic, assign) CGRect inset;

@end

MRDInsetTextField.m

#import "MRDInsetTextField.h"

@implementation MRDInsetTextField

- (id)init
{
    self = [super init];
    if (self) {
        _inset = CGRectZero;
    }
    return self;
}

- (id)initWithCoder:(NSCoder *)aDecoder
{
    self = [super initWithCoder:aDecoder];
    if (self) {
        _inset = CGRectZero;
    }
    return self;
}

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self) {
        _inset = CGRectZero;
    }
    return self;
}

- (void)setInset:(CGRect)inset {
    _inset = inset;

    [self setNeedsLayout];
}

- (CGRect)getRectForBounds:(CGRect)bounds withInset:(CGRect)inset {

    CGRect newRect = CGRectMake(
                         bounds.origin.x + inset.origin.x,
                         bounds.origin.y + inset.origin.y,
                         bounds.origin.x + bounds.size.width - inset.origin.x - inset.size.width,
                         bounds.origin.y + bounds.size.height - inset.origin.y - inset.size.height
                         );

    return newRect;
}

- (CGRect)textRectForBounds:(CGRect)bounds {
    return [self getRectForBounds:[super textRectForBounds:bounds] withInset:_inset];
}

- (CGRect)placeholderRectForBounds:(CGRect)bounds {
    return [self getRectForBounds:bounds withInset:_inset];
}

- (CGRect)editingRectForBounds:(CGRect)bounds {
    return [self getRectForBounds:[super editingRectForBounds:bounds] withInset:_inset];
}

- (CGRect)clearButtonRectForBounds:(CGRect)bounds {
    return CGRectOffset([super clearButtonRectForBounds:bounds], -_inset.size.width, _inset.origin.y/2 - _inset.size.height/2);
}

@end

*_someTextField*来自nib/storyboard视图,带有MRDInsetTextField自定义类的用法示例

[(MRDInsetTextField*)_someTextField setInset:CGRectMake(5, 0, 5, 0)]; // left, top, right, bottom inset

其他回答

解决方案:实际有效且适用于所有情况的解决方案:

应该使用offsetBy而不是insetBy。 也应该调用超函数来获取原始的Rect。 Bounds故障。你需要抵消原来的X, Y,边界有X, Y为零。 原始的x, y可以是非零,例如当设置UITextField的leftView时。

示例:

override func textRect(forBounds bounds: CGRect) -> CGRect {
    return super.textRect(forBounds: bounds).offsetBy(dx: 0.0, dy: 4)
}


override func editingRect(forBounds bounds: CGRect) -> CGRect {
    return super.editingRect(forBounds: bounds).offsetBy(dx: 0.0, dy: 4)
}

我做到了:

myTextField.layer.sublayerTransform = CATransform3DMakeTranslation(5, 0, 0);

当然记得导入QuartzCore并将框架添加到您的项目中。

为UITextField添加填充的一个好方法是子类化UITextField并添加一个edgeInsets属性。然后设置edgeInsets和UITextField将相应地绘制。对于自定义的leftView或rightView集,这也能正确地发挥作用。

OSTextField.h

#import <UIKit/UIKit.h>

@interface OSTextField : UITextField

@property (nonatomic, assign) UIEdgeInsets edgeInsets;

@end

OSTextField.m

#import "OSTextField.h"

@implementation OSTextField

- (id)initWithFrame:(CGRect)frame{
    self = [super initWithFrame:frame];
    if (self) {
        self.edgeInsets = UIEdgeInsetsMake(0, 0, 0, 0);
    }
    return self;
}

-(id)initWithCoder:(NSCoder *)aDecoder{
    self = [super initWithCoder:aDecoder];
    if(self){
        self.edgeInsets = UIEdgeInsetsMake(0, 0, 0, 0);
    }
    return self;
}

- (CGRect)textRectForBounds:(CGRect)bounds {
    return [super textRectForBounds:UIEdgeInsetsInsetRect(bounds, self.edgeInsets)];
}

- (CGRect)editingRectForBounds:(CGRect)bounds {
    return [super editingRectForBounds:UIEdgeInsetsInsetRect(bounds, self.edgeInsets)];
}

@end

如果你只需要左边空白,你可以试试这个:

UItextField *textField = [[UITextField alloc] initWithFrame:...];
UIView *leftView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 10, textField.frame.size.height)];
leftView.backgroundColor = textField.backgroundColor;
textField.leftView = leftView;
textField.leftViewMode = UITextFieldViewModeAlways;

这对我很管用。我希望这能有所帮助。

抛出另一个不需要子类化的解决方案:

UITextField *txtField = [UITextField new];
txtField.borderStyle = UITextBorderStyleRoundedRect;

// grab BG layer
CALayer *bgLayer = txtField.layer.sublayers.lastObject;
bgLayer.opacity = 0.f;

// add new bg view
UIView *bgView = [UIView new];
bgView.backgroundColor = [UIColor whiteColor];
bgView.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
bgView.userInteractionEnabled = NO;

[txtField addSubview: bgView];
[txtField sendSubviewToBack: bgView];

在iOS 7和iOS 8上测试。这两个工作。苹果仍然有可能修改UITextField的层层次结构,把事情搞砸了。