ios 常用基础控件属性

                     目录

        一、UIImageView常用属性

        二、UIButton常用属性

        三、UITextField常用属性

             1、常用属性

             2、计算UILabel高度

             3、设置代理：添加键盘完成按钮，取消第一响应者

 

       一、UIImageView常用属性

         1、图片背景拉伸：类似点9图片

    UIImage *image=[UIImage imageNamed:@"icon"];
    [image stretchableImageWithLeftCapWidth:image.size.width*0.5 topCapHeight:image.size.height*0.5];

       

     2、让imageView的大小和图片的大小保持一致

 //让imageView的大小和图片的大小保持一致
    [self.imageView sizeToFit];

 

     

 

       二、UIButton常用属性

#pragma  mark 设置UIButton属性
- (UIButton *) setUIButtonAttribute:(UIButton *)textButton andPText:(NSString *)text {
          //设置圆角的半径
          [textButton.layer setCornerRadius:15];
          //切割超出圆角范围的子视图
          textButton.layer.masksToBounds = YES;
          //设置边框的颜色
          [textButton.layer setBorderColor:[UIColor whiteColor].CGColor];
          //设置边框的粗细
          [textButton.layer setBorderWidth:0.5];
          //设置字体文字
          [textButton setTitle:text forState:UIControlStateNormal];
          //设置字体颜色
          [textButton  setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal];
    return textButton;
}

 

       三、UITextField常用属性

            1、常用属性

#pragma  mark 设置UITextField属性
- (UITextField *) setUITextFieldAttribute:(UITextField *)textField andPlaceHolderText:(NSString *)placeHolderText andLeftImageName:(UIImage *)leftImage{
           //设置文本提示
           textField.placeholder =placeHolderText;
           //设置光标颜色
           textField.tintColor= [UIColor lightGrayColor];
           //创建左边图标父控件
           UIView *leftViewSup=  [[UIView alloc] initWithFrame:CGRectMake(-20, 0, 30, 20)];
           UIImageView *imageViewPwd=[[UIImageView alloc]initWithFrame:CGRectMake(8, 0, 18, 20)];
           [leftViewSup addSubview:imageViewPwd];
           //设置左边图标
           imageViewPwd.image=leftImage;
           //设置图标
           textField.leftView=leftViewSup;
           //只要输入框有内容就出现清空按钮
           textField.leftViewMode=UITextFieldViewModeAlways;
            /**
             UIControlContentHorizontalAlignmentCenter = 0,//水平居中
             UIControlContentHorizontalAlignmentLeft = 1,//水平居左
             UIControlContentHorizontalAlignmentRight = 2,//水平居右
             UIControlContentHorizontalAlignmentFill = 3, };//水平适应
             */
            //设置文本垂直居中
            textField.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;
            //添加键盘完成按钮注意：这个方法是类方法
            [textField setKeyType];
    
    //设置圆角的半径
    [textField.layer setCornerRadius:15];
     //切割超出圆角范围的子视图
     textField.layer.masksToBounds = YES;
    //设置边框的颜色
     [textField.layer setBorderColor:[UIColor lightGrayColor].CGColor];
     //设置边框的粗细
     [textField.layer setBorderWidth:0.5];
    
    return textField;
}

         

           2、计算UILabel高度

       

/**
 计算UILabel 高度
 */
- (CGSize)getLabelCGSize:(UIFont *)fontSize setTitle:(NSString *)title labelWidth:(CGFloat)labelWidth {
    NSDictionary *attrDict = @{ NSFontAttributeName: fontSize };
    NSAttributedString *attrString = [[NSAttributedString alloc] initWithString:title attributes:attrDict];
    return [attrString boundingRectWithSize:CGSizeMake(labelWidth, MAXFLOAT) options:(NSStringDrawingUsesLineFragmentOrigin) context:nil].size;
}

 

             3、 设置代理：添加键盘完成按钮，取消第一响应者

/**
改变为完成键，如果在项目中导入了YYText框架那么原生的就被替换掉了，
变为returnKeyType = UIKeyboardTypeTwitter;
*/
- (void) setKeyType{
    self.delegate = self;
    self.returnKeyType = UIReturnKeyDone;
}
//实现UITextField代理方法
- (BOOL)textFieldShouldReturn:(UITextField *)textField {
    [self resignFirstResponder];//取消第一响应者
    return YES;
}

   

      4、iOS 改变UITextField placeholder颜色和大小

           iOS11之后，使用UITextField时，它的私有属性_placeholderLabel被禁止访问了。所以我们无法像以前一样使用如下方法改变placeholderLabel的属性了

[textField setValue:[UIColor greenColor] forKeyPath:@"_placeholderLabel.textColor"];

    OC：

    .h

#import <UIKit/UIKit.h>

NS_ASSUME_NONNULL_BEGIN

@interface HanPlaceholderTextField : UITextField
@property(nonatomic, strong) UIColor *placeholderColor;
@property(nonatomic, strong) UIFont  *placeholderFont;
@end

 

  .m

#import "HanPlaceholderTextField.h"
#import <objc/runtime.h>

@interface HanPlaceholderTextField ()
@end

@implementation HanPlaceholderTextField
-(void)changePlaceholder{
    Ivar ivar = class_getInstanceVariable([UITextField class], "_placeholderLabel");
    UILabel *placeholderLabel = object_getIvar(self, ivar);
    placeholderLabel.textColor = _placeholderColor;
    placeholderLabel.font = _placeholderFont;
}
-(void)setPlaceholderColor:(UIColor *)placeholderColor{
    _placeholderColor = placeholderColor;
    [self changePlaceholder];
}
-(void)setPlaceholder:(NSString *)placeholder{
    [super setPlaceholder:placeholder];
    [self changePlaceholder];
}
-(void)setPlaceholderFont:(UIFont *)placeholderFont{
    _placeholderFont = placeholderFont;
    [self changePlaceholder];
}
@end

 

  用法

...
#import "HanPlaceholderTextField.h"
...

....
HanPlaceholderTextField *textField = [[HanPlaceholderTextField alloc] initWithFrame:CGRectMake(0, 100, [UIScreen mainScreen].bounds.size.width, 40)];
textField.placeholderColor = [UIColor redColor];
textField.placeholderFont = [UIFont systemFontOfSize:10];
textField.textColor = [UIColor blueColor];
textField.placeholder = @"你好";
[self.view addSubview:textField];
....