New article Alert and Comment for External Indicators has been published:
In practical work a trader can face the following situation: it is necessary to get "alert" or a text message on a display (in a chart window) indicating about an appeared signal of an indicator. The article contains an example of displaying information about graphical objects created by an external indicator.
Possibilities of the MQL4 programming language do not include the
extended usage of indicator buffers, for example extending them by
adding comment or alert showing, which could be an advantage simplifying
the creation of a program code. On the other hand, MQL4 allows reading
the location of any objects and getting their full characteristics.
In this article I would like to show the method of getting data on a
signal of an indicator attached to a chart and show its comment, alert
or creating a global variable for further use for informational
purposes, for example for passing it to an Expert Advisor.
All marks drawn on a chart use Wingdings
and arrow codes. That is why it is not difficult to get information
about a mark drawn on a chart. By the way, if an indicator author
includes quite an informative description of the OBJ_ARROW object, a
user can easily identify a signal. An example is the description of
marks given by creators of classic Japanese candlesticks. In the
standard performance of his indicator a user needs only to put the mouse
cursor over the mark for getting a pop-up help with a corresponding