IOS开发基础知识--碎片22

1:设置有间距的表格行（UITableViewStyleGrouped）

.设置section的数目，即是你有多少个cell
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {    return ; // in your case, there are 3 cells}
.对于每个section返回一个cell
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{    return ;}
.设置cell之间headerview的高度
- (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section{    return .; // you can have your own choice, of course}
.设置headerview的颜色
- (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section{    UIView *headerView = [[UIView alloc] init];    headerView.backgroundColor = [UIColor clearColor];    return headerView;}
注意：需要使用 indexpath.section 来获得index，而不是用 indexpath.row
cell.textLabel.text=[NSString stringWithFormat:@"%@",[array objectAtIndex:indexPath.section]];

实例：

创建表格代码：

 if (!_myTableView) {
        _myTableView = [[UITableView alloc] initWithFrame:CGRectMake(, CGRectGetMaxY(self.customheadView.frame), Main_Screen_Width, Main_Screen_Height-) style:UITableViewStyleGrouped];
        _myTableView.backgroundColor = [UIColor clearColor];
        _myTableView.showsVerticalScrollIndicator = NO;
        _myTableView.showsHorizontalScrollIndicator=NO;
        _myTableView.dataSource = self;
        _myTableView.delegate = self;
        _myTableView.separatorStyle = UITableViewCellSeparatorStyleNone;
        [_myTableView registerClass:[BLSReplenishmentCell class] forCellReuseIdentifier:BLSReplenishmentViewController_CellIdentifier];
        [self.view addSubview:_myTableView];
    }

其它方法：

#pragma mark UITableViewDataSource和UITableViewDelegate

- (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section
{
    return ;
}

//若设置为0 效果会达不到想要的
- (CGFloat)tableView:(UITableView *)tableView heightForFooterInSection:(NSInteger)section
{
    return ;
}

-(NSInteger)numberOfSectionsInTableView:(nonnull UITableView *)tableView
{
    return self.recordDatalist.count;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section{
    return ;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
    BLSReplenishmentCell *cell = [tableView dequeueReusableCellWithIdentifier:BLSReplenishmentViewController_CellIdentifier forIndexPath:indexPath];
    cell.cur_Replenishment = [self.recordDatalist objectAtIndex:indexPath.section];
    return cell;
}

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{
    return [BLSReplenishmentCell cellHeight];
}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{
    [tableView deselectRowAtIndexPath:indexPath animated:YES];
}

2:Xcode7 使用NSURLSession发送HTTP请求报错

报错内容：控制台打印：Application Transport Security has blocked a cleartext HTTP (http://) resource load since it is insecure. Temporary exceptions can be configured via your app's Info.plist file.

解决办法：修改info.plist文件

3:对UITextField内容实时监听长度和内容

//第一步,对组件增加监听器
[textField addTarget:self action:@selector(textFieldDidChange:) forControlEvents:UIControlEventEditingChanged];
...
//第二步,实现回调函数
- (void) textFieldDidChange:(id) sender {
UITextField *_field = (UITextField *)sender;
NSLog(@"%@,%d",[_field text],_field.text.length);
}

 4:真机调试报Please verify that your device's clock is properly set, and that your signing certificate is not expired

注意：在Tagers-build Settings--Code signing--Code Signing Identity 中的Any IOS SDK记得选对证书

5:给UIAlertView增加UITextView,并获得它的值

MjyAlterView.h

#import <UIKit/UIKit.h>
#import "UIPlaceHolderTextView.h"

typedef void(^AlertViewBlock)(NSInteger index,NSString *textValue);

@interface MjyAlterView : UIAlertView

@property (nonatomic,copy)AlertViewBlock block;

- (instancetype)initWithTitle:(NSString *)title message:(NSString *)message cancelButtonTitle:(NSString *)cancelButtonTitle otherButtonTitles:(NSString *)otherButtonTitles clickButton:(AlertViewBlock)block;

@end

MjyAlterView.m

#import "MjyAlterView.h"

@interface MjyAlterView()<UIAlertViewDelegate,UITextViewDelegate>
@property(copy,nonatomic)NSString *content;
@end

@implementation MjyAlterView

- (instancetype)initWithTitle:(NSString *)title message:(NSString *)message  cancelButtonTitle:(NSString *)cancelButtonTitle otherButtonTitles:(NSString *)otherButtonTitles clickButton:(AlertViewBlock)block{

    self = [super initWithTitle:title message:message delegate:self cancelButtonTitle:cancelButtonTitle otherButtonTitles:otherButtonTitles, nil];
    self.backgroundColor = [UIColor whiteColor];
    UIPlaceHolderTextView *textView = [[UIPlaceHolderTextView alloc]init];
    textView.delegate=self;
    textView.font=[UIFont systemFontOfSize:];
    textView.placeholder=@"输入内容";
    textView.layer.borderColor=[UIColor grayColor].CGColor;
    textView.layer.borderWidth=0.5;
    //    if (SYSTEM_VERSION_LESS_THAN(@"7.0"))//当系统为IOS7时
    //    {
    //    [testAlert addSubview: textView];
    //    }
    //    else//当系统为IOS8
    //    {
    [self setValue: textView forKey:@"accessoryView"];
    //    }
    if (self) {
        _block = block;
    }

    return self;

}

#pragma mark UIAlertViewDelegate

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex{
    if (_block != nil) {
        _block(buttonIndex,self.content);
    }
}

#pragma mark UITextViewDelegate

- (void)textViewDidChange:(UITextView *)textView{
    self.content=textView.text;
}

@end

调用：
__weak ViewController *weakThis = self;
   AlertViewBlock block  = ^(NSInteger index,NSString *content) {
          __strong ViewController *strongThis = weakThis;
        if (index == ) {
            NSLog(@"确定,--%@",content);
        }else if (index == ){

            strongThis.showLabel.text = @"取消";
        }
    };

    MjyAlterView *alterView = [[MjyAlterView alloc] initWithTitle:@""message:@""cancelButtonTitle:nil otherButtonTitles:@"确定" clickButton:block];

    [alterView show];

 6:iOS UILabel显示HTML文本(IOS7以上)

NSString * htmlString = @"<html><body> Some html string \n <font size=\"\" color=\"red\">This is some text!</font> </body></html>";
NSAttributedString * attrStr = [[NSAttributedString alloc] initWithData:[htmlString dataUsingEncoding:NSUnicodeStringEncoding] options:@{ NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType } documentAttributes:nil error:nil];
UILabel * myLabel = [[UILabel alloc] initWithFrame:self.view.bounds];
myLabel.attributedText = attrStr;
[self.view addSubview:myLabel]; 

运用实例（自动高度）

        if (self.contentLabel==nil) {
            self.contentLabel=[[UILabel alloc]init];
            self.contentLabel.textColor=COLOR_WORD_GRAY_1;
            self.contentLabel.font=[UIFont systemFontOfSize:];
            self.contentLabel.numberOfLines=;
            [self.contentLabel sizeToFit];
            [self.contentView addSubview:self.contentLabel];
            [self.contentLabel mas_makeConstraints:^(MASConstraintMaker *make) {
                make.left.mas_equalTo(self.contentView.left).with.offset(leftSpace);
                make.right.mas_equalTo(self.contentView.right).with.offset(-leftSpace);
                make.top.mas_equalTo(self.lineView.bottom).with.offset(topSpace);
            }];
        }

赋值：
        NSAttributedString * attrStr = [[NSAttributedString alloc] initWithData:[model.content dataUsingEncoding:NSUnicodeStringEncoding] options:@{ NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType } documentAttributes:nil error:nil];
        self.contentLabel.attributedText = attrStr;