1.在AppDelegate.h里面设置两个方法：

• (CGFloat)autoScaleW:(CGFloat)w;

• (CGFloat)autoScaleH:(CGFloat)h;

2.在AppDelegate.m里面设置两个属性：
//当前屏幕与设计尺寸(iPhone6)宽度比例
@property (nonatomic, assign)CGFloat autoSizeScaleW;

//当前屏幕与设计尺寸(iPhone6)高度比例
@property (nonatomic, assign)CGFloat autoSizeScaleH;

实现自定义方法 - (void)initAutoScaleSize;
在 - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions;中调用此方法

pragma mark - ScaleSize

• (void)initAutoScaleSize{

  if (kScreenHeight == 480) {
  //********* 4s
  _autoSizeScaleW = kScreenWith / 375;
  _autoSizeScaleH = kScreenHeight / 667;
  }else if (kScreenHeight == 568) {
  //**********5
  _autoSizeScaleW = kScreenWith / 375;
  _autoSizeScaleH = kScreenHeight / 667;
  }else if (kScreenHeight ==667){
  //******** 6
  _autoSizeScaleW = kScreenWith / 375;
  _autoSizeScaleH = kScreenHeight / 667;
  }else if(kScreenHeight == 736){
  //********** 6p
  _autoSizeScaleW = kScreenWith / 375;
  _autoSizeScaleH = kScreenHeight / 667;
  }else{
  _autoSizeScaleW = 1;
  _autoSizeScaleH = 1;
  }

}

• (CGFloat)autoScaleW:(CGFloat)w{

  return w * self.autoSizeScaleW;

}

• (CGFloat)autoScaleH:(CGFloat)h{

  return h * self.autoSizeScaleH;

}

3.在pch文件中设置宏定义

define autoScaleW(width) [(AppDelegate *)[UIApplication sharedApplication].delegate autoScaleW:width]

define autoScaleH(height) [(AppDelegate *)[UIApplication sharedApplication].delegate autoScaleH:height]

4.写控件时设置字体大小：
[UIFont systemFontOfSize:autoScaleW(14)]

设置frame：
CGRectMake(CGRectGetMaxX(self.productNameLabel.frame) + 10 , self.productNameLabel.top + 3, autoScaleW(32),autoScaleW(17));