[RedRain笔记] -iOS功能点收集

• 修改UITextField中Placeholder的文字颜色

[text setValue:[UIColor redColor] forKeyPath:@"_placeholderLabel.textColor"];

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• 修改Label中不同文字颜色

- (void)touchesEnded:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
{
    [self editStringColor:self.label.text editStr:@"好" color:[UIColor blueColor]];
}

- (void)editStringColor:(NSString *)string editStr:(NSString *)editStr color:(UIColor *)color {
    // string为整体字符串, editStr为需要修改的字符串
    NSRange range = [string rangeOfString:editStr];

    NSMutableAttributedString *attribute = [[NSMutableAttributedString alloc] initWithString:string];

    // 设置属性修改字体颜色UIColor与大小UIFont
    [attribute addAttributes:@{NSForegroundColorAttributeName:color} range:range];

    self.label.attributedText = attribute;
}

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• layoutSubviews调用的调用时机

* 当视图第一次显示的时候会被调用
* 当这个视图显示到屏幕上了,点击按钮
* 添加子视图也会调用这个方法
* 当本视图的大小发生改变的时候是会调用的
* 当子视图的frame发生改变的时候是会调用的
* 当删除子视图的时候是会调用的

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• 打印View所有子视图

po [[self view]recursiveDescription]

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• Setting Bundle(编辑设置页面)

http://blog.csdn.net/nogodoss/article/details/21938771

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• IOS 后台挂起程序 当程序到后台后，继续完成Long-Running Task 任务

http://sishuok.com/forum/blogPost/list/8393.html

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• 设置Label的行间距

-（void）test{
    NSMutableAttributedString *attributedString =    
   [[NSMutableAttributedString alloc] initWithString:self.contentLabel.text];
    NSMutableParagraphStyle *paragraphStyle =  [[NSMutableParagraphStyle alloc] init];  
   [paragraphStyle setLineSpacing:3];

    //调整行间距       
   [attributedString addAttribute:NSParagraphStyleAttributeName 
                         value:paragraphStyle 
                         range:NSMakeRange(0, [self.contentLabel.text length])];
     self.contentLabel.attributedText = attributedString;
}

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• iOS 开发中一些相关的路径

模拟器的位置:
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs 

文档安装位置:
/Applications/Xcode.app/Contents/Developer/Documentation/DocSets

插件保存路径:
~/Library/ApplicationSupport/Developer/Shared/Xcode/Plug-ins

自定义代码段的保存路径:
~/Library/Developer/Xcode/UserData/CodeSnippets/ 
如果找不到CodeSnippets文件夹，可以自己新建一个CodeSnippets文件夹。

证书路径
~/Library/MobileDevice/Provisioning Profiles