Hexagons

guiInit

int guiInit(int hwnd, string short_name, int autostate_enabled = 1);
Parameter Description
hwnd Chart window handle (e.g., WindowHandle(_Symbol, _Period)).
short_name Program name for cache partitioning (e.g., MQL_PROGRAM_NAME). Empty shares one bucket per chart (legacy/tests).
autostate_enabled Non-zero (default): save/restore on OnDeinit → OnInit. 0: disable both.

Wrapper (recommended for most indicators):

int guiInit(int autostate_enabled = 1);
// Uses WindowHandle(_Symbol, _Period), MQL_PROGRAM_NAME, autostate on.

guiDeinit

void guiDeinit(int gui_id);

Destroys that session's chart objects and menu rows. No-op when gui_id <= 0 or unknown. When autostate is enabled, snapshots restorable objects before teardown.

guiHasRestoredState

bool guiHasRestoredState(int gui_id, int handle);

Returns true if a cached snapshot was applied when this object was created (re-attach after OnDeinit). Used internally by guiAddCheckbox / guiAddRadio to skip initial_checked / initial_selected presets when the user's last state was restored.

#include <guipro.mqh>

int gui_id;

//
int OnInit()
{
   gui_id = guiInit();
   if(gui_id <= 0)
      return(INIT_FAILED);

   // guiAdd*, guiAddMenu, ...
   return(INIT_SUCCEEDED);
}  // OnInit

//
void OnDeinit(const int reason)
{
   guiDeinit(gui_id);
}  // OnDeinit

Always call guiDeinit from OnDeinit. Do not rely on DLL unload for cleanup.

Minimal Indicator Example

One button, lifecycle, and click polling.

#property strict
#property indicator_chart_window
#include <guipro.mqh>

int gui_id;
int btn_handle;

//
int OnInit()
{
   gui_id = guiInit();
   btn_handle = guiAddButton(gui_id, 20, 20, 120, 28, "Click me");
   return(INIT_SUCCEEDED);
}  // OnInit

//
void OnDeinit(const int reason)
{
   guiDeinit(gui_id);
}  // OnDeinit

//
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[])
{
   if(guiIsClicked(gui_id, btn_handle))
      Print("Button clicked");

   return(rates_total);
}  // OnCalculate

Threading

Drive each gui_id from a single thread of control in normal indicator use (typically OnCalculate). Do not call the same session from multiple MQL threads or timers without your own ordering.