MQ4 Expert Advisor (EA) for the gold trading system described requires coding the rules in MetaEditor (MQL4). Below is a step-by-step breakdown of how to build the EA, including key logic, entry/exit conditions, and risk management.
Step 1: Define EA Parameters (Input Variables)
These are adjustable in the MT4 settings:
// Input parameters
input double LotSize = 0.1; // Fixed lot size
input int StopLoss = 30; // SL in pips
input int TakeProfit = 60; // TP in pips (1:2 risk ratio)
input int EMA_Fast_Period = 9; // Fast EMA
input int EMA_Medium_Period = 21; // Medium EMA
input int EMA_Slow_Period = 50; // Slow EMA (trend filter)
input int MinCandleSize = 10; // Min candle size (pips) to avoid noise
input bool UseCandlePatterns = true;// Enable candlestick patterns
input string TradeSession = "08:00-17:00"; // London/NY sessionStep 2: Trend Filter (EMA Alignment)
Check if EMAs are aligned for uptrend (buy) or downtrend (sell):
bool IsUptrend() {
double emaFast = iMA(NULL, 0, EMA_Fast_Period, 0, MODE_EMA, PRICE_CLOSE, 1);
double emaMedium = iMA(NULL, 0, EMA_Medium_Period, 0, MODE_EMA, PRICE_CLOSE, 1);
double emaSlow = iMA(NULL, 0, EMA_Slow_Period, 0, MODE_EMA, PRICE_CLOSE, 1);
return (emaFast > emaMedium && emaMedium > emaSlow && Close[1] > emaSlow);
}
bool IsDowntrend() {
double emaFast = iMA(NULL, 0, EMA_Fast_Period, 0, MODE_EMA, PRICE_CLOSE, 1);
double emaMedium = iMA(NULL, 0, EMA_Medium_Period, 0, MODE_EMA, PRICE_CLOSE, 1);
double emaSlow = iMA(NULL, 0, EMA_Slow_Period, 0, MODE_EMA, PRICE_CLOSE, 1);
return (emaFast < emaMedium && emaMedium < emaSlow && Close[1] < emaSlow);
}Step 3: Candlestick Pattern Detection
Detect bullish/bearish reversal patterns (e.g., engulfing, pin bars):
bool IsBullishEngulfing() {
if (Close[1] > Open[1] && Open[2] > Close[2] && Close[1] > Open[2] && Open[1] < Close[2])
return true;
return false;
}
bool IsBearishEngulfing() {
if (Close[1] < Open[1] && Open[2] < Close[2] && Close[1] < Open[2] && Open[1] > Close[2])
return true;
return false;
}Step 4: Entry Logic
Combine trend + pullback + candlestick signal:
void CheckEntries() {
// Check if in trading session (optional)
if (!IsTradingSession()) return;
// Long entry (Buy)
if (IsUptrend() && IsPullbackToEMA21() && (IsBullishEngulfing() || !UseCandlePatterns)) {
double sl = Bid - StopLoss * Point;
double tp = Bid + TakeProfit * Point;
OrderSend(Symbol(), OP_BUY, LotSize, Ask, 3, sl, tp, "Gold EA Buy", 0, 0, Green);
}
// Short entry (Sell)
if (IsDowntrend() && IsPullbackToEMA21() && (IsBearishEngulfing() || !UseCandlePatterns)) {
double sl = Ask + StopLoss * Point;
double tp = Ask - TakeProfit * Point;
OrderSend(Symbol(), OP_SELL, LotSize, Bid, 3, sl, tp, "Gold EA Sell", 0, 0, Red);
}
}Step 5: Exit Logic
Close trades when TP/SL is hit or trend reverses:
void CheckExits() {
for (int i = OrdersTotal() - 1; i >= 0; i--) {
if (OrderSelect(i, SELECT_BY_POS, MODE_TRADES)) {
// Close if trend reverses
if ((OrderType() == OP_BUY && IsDowntrend()) || (OrderType() == OP_SELL && IsUptrend())) {
OrderClose(OrderTicket(), OrderLots(), OrderType() == OP_BUY ? Bid : Ask, 3, Red);
}
}
}
}Step 6: Full EA Structure
int OnInit() { return INIT_SUCCEEDED; }
void OnTick() {
CheckExits(); // Close trades if needed
CheckEntries(); // Open new trades
}How to Use the EA
- Copy the code into MetaEditor (File → New → Expert Advisor).
- Compile (F7) and attach to an MT4 chart (XAU/USD M15/H1).
- Adjust parameters (e.g., lot size, SL/TP, EMAs).
- Backtest in Strategy Tester (Ctrl+R) to verify the 70%+ win rate.
Optimization Tips
- Test different EMA periods (e.g., 5-9-21 vs. 9-21-50).
- Adjust TP/SL ratios (e.g., 1:1.5 vs. 1:2).
- Add trailing stops to maximize profits.
Would you like me to add additional features (e.g., news filter, trailing stop)? Let me know! 🚀