三均线系统指标（EMA20/49/89）

#property copyright "XAUOF指标工坊"
#property version   "1.00"
#property indicator_chart_window
#property indicator_buffers 3
#property indicator_plots   3

// 第一条均线
#property indicator_type1   DRAW_LINE
#property indicator_color1  clrDodgerBlue
#property indicator_width1  2
#property indicator_label1  "EMA快线"

// 第二条均线
#property indicator_type2   DRAW_LINE
#property indicator_color2  clrOrange
#property indicator_width2  2
#property indicator_label2  "EMA中线"

// 第三条均线
#property indicator_type3   DRAW_LINE
#property indicator_color3  clrMagenta
#property indicator_width3  2
#property indicator_label3  "EMA慢线"

//--- 输入参数
input group "===== 快线设置 ====="
input int    FastPeriod  = 20;              // 快线周期（推荐20）
input color  FastColor   = clrDodgerBlue;   // 快线颜色
input int    FastWidth   = 2;               // 快线粗细（1-5）

input group "===== 中线设置 ====="
input int    MidPeriod   = 49;              // 中线周期（推荐49）
input color  MidColor    = clrOrange;       // 中线颜色
input int    MidWidth    = 2;               // 中线粗细（1-5）

input group "===== 慢线设置 ====="
input int    SlowPeriod  = 89;              // 慢线周期（推荐89）
input color  SlowColor   = clrMagenta;      // 慢线颜色
input int    SlowWidth   = 2;               // 慢线粗细（1-5）

//--- 指标缓冲区
double FastBuffer[];
double MidBuffer[];
double SlowBuffer[];

//--- 指标句柄
int FastHandle;
int MidHandle;
int SlowHandle;

//+------------------------------------------------------------------+
//| 自定义指标初始化函数                                                |
//+------------------------------------------------------------------+
int OnInit()
{
   // 参数合法性检查
   if(FastPeriod < 1 || MidPeriod < 1 || SlowPeriod < 1)
   {
      Print("均线周期必须大于0");
      return INIT_PARAMETERS_INCORRECT;
   }
   
   // 绑定指标缓冲区
   SetIndexBuffer(0, FastBuffer, INDICATOR_DATA);
   SetIndexBuffer(1, MidBuffer, INDICATOR_DATA);
   SetIndexBuffer(2, SlowBuffer, INDICATOR_DATA);
   
   // 创建EMA句柄
   FastHandle = iMA(_Symbol, PERIOD_CURRENT, FastPeriod, 0, MODE_EMA, PRICE_CLOSE);
   MidHandle  = iMA(_Symbol, PERIOD_CURRENT, MidPeriod, 0, MODE_EMA, PRICE_CLOSE);
   SlowHandle = iMA(_Symbol, PERIOD_CURRENT, SlowPeriod, 0, MODE_EMA, PRICE_CLOSE);
   
   if(FastHandle == INVALID_HANDLE || MidHandle == INVALID_HANDLE || SlowHandle == INVALID_HANDLE)
   {
      Print("创建均线句柄失败");
      return INIT_FAILED;
   }
   
   // 设置绘图属性
   PlotIndexSetInteger(0, PLOT_LINE_COLOR, FastColor);
   PlotIndexSetInteger(0, PLOT_LINE_WIDTH, FastWidth);
   
   PlotIndexSetInteger(1, PLOT_LINE_COLOR, MidColor);
   PlotIndexSetInteger(1, PLOT_LINE_WIDTH, MidWidth);
   
   PlotIndexSetInteger(2, PLOT_LINE_COLOR, SlowColor);
   PlotIndexSetInteger(2, PLOT_LINE_WIDTH, SlowWidth);
   
   // 设置指标标签
   PlotIndexSetString(0, PLOT_LABEL, "EMA(" + IntegerToString(FastPeriod) + ")");
   PlotIndexSetString(1, PLOT_LABEL, "EMA(" + IntegerToString(MidPeriod) + ")");
   PlotIndexSetString(2, PLOT_LABEL, "EMA(" + IntegerToString(SlowPeriod) + ")");
   
   // 设置指标名称
   IndicatorSetString(INDICATOR_SHORTNAME, 
      "三均线系统(" + IntegerToString(FastPeriod) + "," + 
      IntegerToString(MidPeriod) + "," + IntegerToString(SlowPeriod) + ")");
   
   // 设置指标精度
   IndicatorSetInteger(INDICATOR_DIGITS, _Digits);
   
   return INIT_SUCCEEDED;
}

//+------------------------------------------------------------------+
//| 自定义指标迭代函数                                                  |
//+------------------------------------------------------------------+
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[])
{
   // 检查K线数量是否足够
   if(rates_total < SlowPeriod)
      return 0;
   
   // 等待指标数据计算完成
   if(BarsCalculated(FastHandle) < rates_total) return 0;
   if(BarsCalculated(MidHandle) < rates_total) return 0;
   if(BarsCalculated(SlowHandle) < rates_total) return 0;
   
   // 确定计算起点
   int start = 0;
   if(prev_calculated > 0)
      start = prev_calculated - 1;
   
   // 计算需要复制的数据量
   int to_copy = rates_total - start;
   
   // 从指标句柄复制数据到缓冲区
   if(CopyBuffer(FastHandle, 0, start, to_copy, FastBuffer) <= 0)
   {
      Print("复制快线数据失败");
      return 0;
   }
   
   if(CopyBuffer(MidHandle, 0, start, to_copy, MidBuffer) <= 0)
   {
      Print("复制中线数据失败");
      return 0;
   }
   
   if(CopyBuffer(SlowHandle, 0, start, to_copy, SlowBuffer) <= 0)
   {
      Print("复制慢线数据失败");
      return 0;
   }
   
   return rates_total;
}

//+------------------------------------------------------------------+
//| 指标清理函数                                                       |
//+------------------------------------------------------------------+
void OnDeinit(const int reason)
{
   // 释放指标句柄
   if(FastHandle != INVALID_HANDLE)
      IndicatorRelease(FastHandle);
   if(MidHandle != INVALID_HANDLE)
      IndicatorRelease(MidHandle);
   if(SlowHandle != INVALID_HANDLE)
      IndicatorRelease(SlowHandle);
}
//+------------------------------------------------------------------+