EMA双均线金叉箭头指标

#property copyright "XAUOF指标工坊"
#property version   "1.00"
#property strict
#property indicator_chart_window
#property indicator_buffers 4
#property indicator_plots   4

// 画线1：快速EMA

#property indicator_label1  "EMA快线"
#property indicator_type1   DRAW_LINE
#property indicator_color1  clrDodgerBlue
#property indicator_width1  2

// 画线2：慢速EMA

#property indicator_label2  "EMA慢线"
#property indicator_type2   DRAW_LINE
#property indicator_color2  clrOrange
#property indicator_width2  2

// 画线3：上穿箭头

#property indicator_label3  "金叉"
#property indicator_type3   DRAW_ARROW
#property indicator_color3  clrLime
#property indicator_width3  3

// 画线4：下穿箭头

#property indicator_label4  "死叉"
#property indicator_type4   DRAW_ARROW
#property indicator_color4  clrRed
#property indicator_width4  3

//--- 可调参数

input int FastPeriod = 20;  // 快线周期（推荐 20）

input int SlowPeriod = 60;  // 慢线周期（推荐 60）


//--- 指标缓冲区

double FastBuffer[];   // 快线值

double SlowBuffer[];   // 慢线值

double UpArrow[];      // 上穿箭头

double DnArrow[];      // 下穿箭头


int fast_handle;       // 快线句柄

int slow_handle;       // 慢线句柄


//+------------------------------------------------------------------+

int OnInit()
{
   // 参数合法性检查

   if(FastPeriod <= 0 || SlowPeriod <= 0 || FastPeriod >= SlowPeriod)
   {
      Print("参数错误：快线周期必须小于慢线周期且均大于0");
      return(INIT_PARAMETERS_INCORRECT);
   }
   
   // 创建 EMA 句柄

   fast_handle = iMA(_Symbol, _Period, FastPeriod, 0, MODE_EMA, PRICE_CLOSE);
   slow_handle = iMA(_Symbol, _Period, SlowPeriod, 0, MODE_EMA, PRICE_CLOSE);
   
   if(fast_handle == INVALID_HANDLE || slow_handle == INVALID_HANDLE)
   {
      Print("创建均线句柄失败");
      return(INIT_FAILED);
   }
   
   // 绑定缓冲区

   SetIndexBuffer(0, FastBuffer, INDICATOR_DATA);
   SetIndexBuffer(1, SlowBuffer, INDICATOR_DATA);
   SetIndexBuffer(2, UpArrow, INDICATOR_DATA);
   SetIndexBuffer(3, DnArrow, INDICATOR_DATA);
   
   // 设置数组为时间序列（索引0为最新）

   ArraySetAsSeries(FastBuffer, true);
   ArraySetAsSeries(SlowBuffer, true);
   ArraySetAsSeries(UpArrow, true);
   ArraySetAsSeries(DnArrow, true);
   
   // 设置箭头符号（233=向上箭头，234=向下箭头）

   PlotIndexSetInteger(2, PLOT_ARROW, 233);
   PlotIndexSetInteger(3, PLOT_ARROW, 234);
   
   // 设置空值

   PlotIndexSetDouble(2, PLOT_EMPTY_VALUE, 0);
   PlotIndexSetDouble(3, PLOT_EMPTY_VALUE, 0);
   
   return(INIT_SUCCEEDED);
}

//+------------------------------------------------------------------+

void OnDeinit(const int reason)
{
   // 释放句柄

   if(fast_handle != INVALID_HANDLE) IndicatorRelease(fast_handle);
   if(slow_handle != INVALID_HANDLE) IndicatorRelease(slow_handle);
}

//+------------------------------------------------------------------+

int OnCalculate(const int rates_total,
                const int prev_calculated,
                const datetime &time[],
                const double &open[],
                const double &high[],
                const double &low[],
                const double &close[],
                const long &tick_volume[],
                const long &volume[],
                const int &spread[])
{
   // 数据不足，不计算

   if(rates_total < SlowPeriod) return(0);
   
   // 设置价格数组为时间序列

   ArraySetAsSeries(high, true);
   ArraySetAsSeries(low, true);
   
   // 从指标句柄复制数据

   if(CopyBuffer(fast_handle, 0, 0, rates_total, FastBuffer) <= 0) return(0);
   if(CopyBuffer(slow_handle, 0, 0, rates_total, SlowBuffer) <= 0) return(0);
   
   // 确定计算起点

   int start = prev_calculated > 0 ? prev_calculated - 1 : SlowPeriod;
   if(start < 1) start = 1; // 至少从第1根开始（因为要判断前一根）

   
   // 逐根K线计算交叉信号

   for(int i = start; i < rates_total; i++)
   {
      // 清空箭头

      UpArrow[i] = 0;
      DnArrow[i] = 0;
      
      // 判断交叉：当前快线在慢线上方 且 前一根快线在慢线下方 = 上穿

      if(FastBuffer[i] > SlowBuffer[i] && FastBuffer[i-1] <= SlowBuffer[i-1])
      {
         UpArrow[i] = low[i] - 10 * _Point; // 画在K线下方

      }
      
      // 判断交叉：当前快线在慢线下方 且 前一根快线在慢线上方 = 下穿

      if(FastBuffer[i] < SlowBuffer[i] && FastBuffer[i-1] >= SlowBuffer[i-1])
      {
         DnArrow[i] = high[i] + 10 * _Point; // 画在K线上方

      }
   }
   
   return(rates_total);
}