New article Graphical Interfaces IV: the Multi-Window Mode and System of Priorities (Chapter 2) has been published:
this chapter, we will extend the library implementation to the
possibility of creating multi-window interfaces for the MQL
applications. We will also develop a system of priorities for left mouse
clicking on graphical objects. This is required to avoid problems when
elements do not respond to the user's actions.
Let us consider the multi-window mode of the graphical interface of the library under development. Up to now, the ENUM_WINDOW_TYPE enumeration provided two identifiers for the main (W_MAIN) and dialog (W_DIALOG)
windows. The single-window mode was the only mode in use. After we
introduce some additions, enabling the multi-window mode will simply
involve the creation and addition of the required number of control
forms to the base.
In the main class for event handling CWndEvents create a field for storing the index of the currently active window.
class CWndEvents : public CWndContainer
//--- Index of the active window
Let us see how the index of the active window is going to be
identified. For instance, the user assigns the opening of a dialog
window (W_DIALOG) to some button. When the button is pressed, the ON_CLICK_BUTTON custom event is generated. This event can be tracked in the CProgram::OnEvent() event handler of the custom class. We will also use the CWindow::Show()
method of the form which is to be shown. It is not sufficient in the
current implementation of the library and we will introduce necessary
Author: Anatoli Kazharski
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