IOS客户端Coding项目记录(四)

1:打开Xcode，然后闪退，报加载某库出现异常

如/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/libclang.dylib
这个是Xcode的bug，我的情况是打开某个项目会出现这个问题
解决办法：这还是缓存问题，详见第五点（5、XCode5由于缓存问题引起了很多奇怪的问题，所以清除缓存有时会起到大作用：），清除缓存再运行，一切正常。
进入步骤，按option键进入资源库，Developer—xcode—DerivedData把里面的文件清除就可以

2:加快CocoaPod安装插件的速度

（这样也解决一些插件下载时失败的问题，因为一些源代码的内容是不必要，而提供的地址却连接不到，导致报错，而无法更新）
$ pod install --no-repo-update 

3:userInteractionEnabled属性

当视图对象的userInteractionEnabled设置为NO的时候，用户触发的事件，如触摸，键盘等，将会被该视图忽略（其他视图照常响应），并且该视图对象也会从事件响应队列中被移除。 当userInteractionEnabled设为YES时，则事件可以正常的传递给该视图对象。 userInteractionEnabled的属性默认值就是YES。
EaseUserHeaderView *headerView = [[EaseUserHeaderView alloc] init];
headerView.userInteractionEnabled = YES;

4:字符串显示问题，同一行不同的效果

调用：
[_fansCountBtn setAttributedTitle:[self getStringWithTitle:@"粉丝" andValue:_curUser.fans_count.stringValue] forState:UIControlStateNormal];

方法：
- (NSMutableAttributedString*)getStringWithTitle:(NSString *)title andValue:(NSString *)value{
    NSMutableAttributedString *attriString = [[NSMutableAttributedString alloc] initWithString:[NSString stringWithFormat:@"%@ %@", value, title]];
    [attriString addAttributes:@{NSFontAttributeName : [UIFont boldSystemFontOfSize:17],
                                 NSForegroundColorAttributeName : [UIColor whiteColor]}
                         range:NSMakeRange(0, value.length)];
    
    [attriString addAttributes:@{NSFontAttributeName : [UIFont systemFontOfSize:14],
                                 NSForegroundColorAttributeName : [UIColor whiteColor]}
                         range:NSMakeRange(value.length+1, title.length)];
    return  attriString;
}

另：label可以调用sizeToFit来调整内容适应

_userLabel.text = _curUser.name;
[_userLabel sizeToFit];

5:NSArray中使用firstObject和lastObject

NSArray有lastObject方法用来获取数组最后一个对象,firstObject来获取数组第一个对象,NSArray中使用firstObject和lastObject的好处在于，当数组为空时，返回nil，而不会报错。当数组为空，使用myArray[0]时，会报错。

NSNumber *firstLevel = nil, *secondLevel = nil;
NSArray *locationArray = [_curUser.location componentsSeparatedByString:@" "];
                        if (locationArray.count == 2) {
                            firstLevel = [AddressManager indexOfFirst:[locationArray firstObject]];
                            secondLevel = [AddressManager indexOfSecond:[locationArray lastObject] inFirst:[locationArray firstObject]];
                        }

6:日期控件ActionSheetDatePicker  多级控件ActionSheetStringPicker

小实例：
                    NSDate *curDate = [NSDate dateFromString:_curUser.birthday withFormat:@"yyyy-MM-dd"];
                    if (!curDate) {
                        curDate = [NSDate dateFromString:@"1990-01-01" withFormat:@"yyyy-MM-dd"];
                    }
                    ActionSheetDatePicker *picker = [[ActionSheetDatePicker alloc] initWithTitle:nil datePickerMode:UIDatePickerModeDate selectedDate:curDate doneBlock:^(ActionSheetDatePicker *picker, NSDate *selectedDate, id origin) {
                        NSString *preValue = weakSelf.curUser.birthday;
                        weakSelf.curUser.birthday = [selectedDate string_yyyy_MM_dd];
                        [weakSelf.myTableView reloadData];
                        [[Coding_NetAPIManager sharedManager] request_UpdateUserInfo_WithObj:weakSelf.curUser andBlock:^(id data, NSError *error) {
                            if (data) {
                                weakSelf.curUser = data;
                            }else{
                                weakSelf.curUser.birthday = preValue;
                            }
                            [weakSelf.myTableView reloadData];
                        }];
                    } cancelBlock:^(ActionSheetDatePicker *picker) {
                        NSLog(@"%@", picker.description);
                    } origin:self.view];
                    picker.minimumDate = [[NSDate date] offsetYear:-120];
                    picker.maximumDate = [NSDate date];
                    [picker showActionSheetPicker];

小实例：

[ActionSheetStringPicker showPickerWithTitle:nil rows:@[[AddressManager firstLevelArray], [AddressManager secondLevelMap]] initialSelection:@[firstLevel, secondLevel] doneBlock:^(ActionSheetStringPicker *picker, NSArray * selectedIndex, NSArray *selectedValue) {
                        NSString *preValue = weakSelf.curUser.location;
                        NSString *location = [selectedValue componentsJoinedByString:@" "];
                        weakSelf.curUser.location = location;
                        [weakSelf.myTableView reloadData];
                        [[Coding_NetAPIManager sharedManager] request_UpdateUserInfo_WithObj:weakSelf.curUser andBlock:^(id data, NSError *error) {
                            if (data) {
                                weakSelf.curUser = data;
                            }else{
                                weakSelf.curUser.location = preValue;
                            }
                            [weakSelf.myTableView reloadData];
                        }];
                    } cancelBlock:nil origin:self.view];

小实例：

[ActionSheetStringPicker showPickerWithTitle:nil rows:@[@[@"男", @"女", @"未知"]] initialSelection:@[_curUser.sex] doneBlock:^(ActionSheetStringPicker *picker, NSArray * selectedIndex, NSArray *selectedValue) {
                        NSNumber *preValue = weakSelf.curUser.sex;
                        weakSelf.curUser.sex = [selectedIndex firstObject];
                        [weakSelf.myTableView reloadData];
                        [[Coding_NetAPIManager sharedManager] request_UpdateUserInfo_WithObj:weakSelf.curUser andBlock:^(id data, NSError *error) {
                            if (data) {
                                weakSelf.curUser = data;
                            }else{
                                weakSelf.curUser.sex = preValue;
                            }
                            [weakSelf.myTableView reloadData];
                        }];
                    } cancelBlock:nil origin:self.view];

7:代码自动布局Masonry插件

Masonry支持哪一些属性@property (nonatomic, strong, readonly) MASConstraint *left;
@property (nonatomic, strong, readonly) MASConstraint *top;
@property (nonatomic, strong, readonly) MASConstraint *right;
@property (nonatomic, strong, readonly) MASConstraint *bottom;
@property (nonatomic, strong, readonly) MASConstraint *leading;
@property (nonatomic, strong, readonly) MASConstraint *trailing;
@property (nonatomic, strong, readonly) MASConstraint *width;
@property (nonatomic, strong, readonly) MASConstraint *height;
@property (nonatomic, strong, readonly) MASConstraint *centerX;
@property (nonatomic, strong, readonly) MASConstraint *centerY;
@property (nonatomic, strong, readonly) MASConstraint *baseline;

小实例：

        if (!_titleL) {
            _titleL = [[UILabel alloc] init];
            [self.contentView addSubview:_titleL];
            _titleL.font = [UIFont systemFontOfSize:16];
            _titleL.textColor = [UIColor blackColor];
        }
        if (!_valueL) {
            _valueL = [[UILabel alloc] init];
            _valueL.numberOfLines = 0;
            [self.contentView addSubview:_valueL];
            _valueL.font = [UIFont systemFontOfSize:15];
            _valueL.textColor = [UIColor colorWithHexString:@"0x999999"];
        }
        
        [_titleL mas_makeConstraints:^(MASConstraintMaker *make) {
            make.left.equalTo(self.contentView).offset(kPaddingLeftWidth);
            make.height.mas_equalTo(20);
            make.top.equalTo(self.contentView).offset(12);
            make.width.mas_equalTo(kScreen_Width - 2*kPaddingLeftWidth);
        }];
        [_valueL mas_makeConstraints:^(MASConstraintMaker *make) {
            make.top.equalTo(_titleL.mas_bottom).offset(12);
            make.left.right.equalTo(_titleL);
        }];
实例（注意右边跟下边要用负数）：

    UIView *sv=[UIView new];

    sv.backgroundColor=[UIColor redColor]；

    [self.view addSubview:sv];

    //定义一个剧中大小

    [sv mas_makeConstraints:^(MASConstraintMaker *make) {

        make.center.equalTo(self.view);

        make.size.mas_equalTo(CGSizeMake(300, 300));

    }];

    

    UIView *childView=[UIView new];

    childView.backgroundColor=[UIColor greenColor];

    [sv addSubview:childView];

        //相对父视图

    [childView mas_makeConstraints:^(MASConstraintMaker *make) {

       make.left.equalTo(sv.mas_left).with.offset(20);

        make.top.equalTo(sv.mas_top).with.offset(10);

        make.right.equalTo(sv.mas_right).with.offset(-20);

        make.height.equalTo(@200);

    }];

    UIView *otherChildView=[UIView new];

    otherChildView.backgroundColor=[UIColor yellowColor];

    [sv addSubview:otherChildView];

   

    //相对父视图跟兄弟视图

    [otherChildView mas_makeConstraints:^(MASConstraintMaker *make) {

        make.top.equalTo(childView.mas_bottom).with.offset(10);

        make.bottom.equalTo(sv.mas_bottom).with.offset(-10);

        make.left.equalTo(sv.mas_left).with.offset(10);

        make.width.mas_equalTo(@240);

    }];

另一实例：

    // 先给redBtn添加约束

    [redBtn mas_makeConstraints:^(MASConstraintMaker *make) {

        // 添加左、上边距约束

        // 添加上边距约束

        make.top.mas_equalTo(100);

        // 添加左边距约束

        make.left.mas_equalTo(20);

        // 添加右边距约束

        make.right.mas_equalTo(-20);

    }];

        // 还是老规矩 先初始化一个btn

    UIButton * blueBtn = [UIButton new];

    blueBtn.backgroundColor = [UIColor blueColor];

    [self.view addSubview:blueBtn];

       // 给蓝色btn添加约束

    [blueBtn mas_makeConstraints:^(MASConstraintMaker *make) {

             // 添加右、下边距约束

        // make.bottom.and.right.mas_equalTo(-20);

           // 添加下边距约束

        make.bottom.mas_equalTo(-20);

        // 添加右边距约束

        make.right.mas_equalTo(-20);

        // 添加高度约束，让高度等于红色Btn

        make.height.equalTo(redBtn);

       // 添加上边距约束（上边距 = 红色btn的下边框 + 偏移量20）

        make.top.equalTo(redBtn.mas_bottom).offset(20);

        // 添加左边距（左边距 = 父容器纵轴中心 + 偏移量0）

        make.left.equalTo(weakSelf.view.mas_centerX).offset(0);

    }];

好文章：http://www.cocoachina.com/ios/20141219/10702.html

关于更新布局mas_updateConstraints的运用

实例一：

#import "Masonry.h"

@interface ViewController5()

@property(strong,nonatomic)UILabel *myLabel;

@end

@implementation ViewController5

-(void)viewDidLoad
{
    [super viewDidLoad];
    self.myLabel=[UILabel new];
    self.myLabel.text=@"GOOD";
    self.myLabel.backgroundColor=[UIColor blueColor];
    [self.view addSubview:self.myLabel];
    
    [self.myLabel mas_makeConstraints:^(MASConstraintMaker *make) {
        make.left.mas_equalTo(self.view.mas_left).with.offset(20);
        make.bottom.mas_equalTo(self.view.mas_bottom).with.offset(-20);
        make.size.mas_equalTo(CGSizeMake(100, 50));
    }];
}
- (IBAction)actionBtn:(id)sender {
    CGFloat newBottom=-50;
    //修改布局
    [_myLabel mas_updateConstraints:^(MASConstraintMaker *make) {
        make.bottom.mas_equalTo(newBottom);
    }];
    
    //要进行layoutIfNeeded 才有效果
    [self.myLabel layoutIfNeeded];
}
@end



实例二：
（修改键盘跟输入框的隐藏问题）
#import "Masonry.h"

@interface ViewController4 ()

@property (strong, nonatomic) UITextField *textField;

@end

@implementation ViewController4

- (void)dealloc {
    
    [[NSNotificationCenter defaultCenter] removeObserver:self];
}

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    
    __weak typeof(self) weakSelf = self;
    
    _textField = [UITextField new];
    _textField.backgroundColor = [UIColor redColor];
    [self.view addSubview:_textField];
    
    [_textField mas_makeConstraints:^(MASConstraintMaker *make) {
        
        make.left.mas_equalTo(10);
        make.centerX.equalTo(weakSelf.view);
        make.bottom.mas_equalTo(0);
        make.height.mas_equalTo(40);
    }];
    
    // 注册键盘通知
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillChangeFrameNotification:) name:UIKeyboardWillChangeFrameNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHideNotification:) name:UIKeyboardWillHideNotification object:nil];
}

- (void)keyboardWillChangeFrameNotification:(NSNotification *)notification {
    
    // 获取键盘基本信息（动画时长与键盘高度）
    NSDictionary *userInfo = [notification userInfo];
    CGRect rect = [userInfo[UIKeyboardFrameBeginUserInfoKey] CGRectValue];
    CGFloat keyboardHeight = CGRectGetHeight(rect);
    CGFloat keyboardDuration = [userInfo[UIKeyboardAnimationDurationUserInfoKey] doubleValue];
    
    // 修改下边距约束
    [_textField mas_updateConstraints:^(MASConstraintMaker *make) {
        
        make.bottom.mas_equalTo(-keyboardHeight);
    }];
    
    // 更新约束
    [UIView animateWithDuration:keyboardDuration animations:^{
        
        [self.view layoutIfNeeded];
    }];
}

- (void)keyboardWillHideNotification:(NSNotification *)notification {
    
    // 获得键盘动画时长
    NSDictionary *userInfo = [notification userInfo];
    CGFloat keyboardDuration = [userInfo[UIKeyboardAnimationDurationUserInfoKey] doubleValue];
    
    // 修改为以前的约束（距下边距0）
    [_textField mas_updateConstraints:^(MASConstraintMaker *make) {
        
        make.bottom.mas_equalTo(0);
    }];
    
    // 更新约束
    [UIView animateWithDuration:keyboardDuration animations:^{
        
        [self.view layoutIfNeeded];
    }];
}

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
    
    [super touchesBegan:touches withEvent:event];
    [self.view endEditing:YES];
}

@end