Tag Archives: Events

Hyperlink controls

Following on from the previous post on Label controls another new item we’ve added to OpenInsight is the Hyperlink control, which is essentially a specialized Label control that allows you to implement clickable links on your forms.

Hyperlink Control

Hyperlink Control

Barring HTML rendering it supports all the other properties of a Label control as well as adding a few others:

  • AUTOUNDERLINE
  • LINK
  • LINKCURSOR
  • LINKRESULT
  • SHOWVISITED
  • VISITEDFORECOLOR

AUTOUNDERLINE property

If this property is TRUE then the control ensures the text is underlined when the mouse hovers over it.

LINK property

This property contains the command string to execute when the link is (single) clicked. it can be any valid Windows command string (internally it is passed to the Windows ShellExecute function).

Note that that the CLICK and DBLCLK events are still fired as normal even if the LINK property is blank, so you still have full control over the hyperlink target.

LINKCURSOR property

This specifies the cursor to use when the mouse is over the link text.  It defaults to the standard “hand” cursor but can be set in the same way as the normal OpenInsight CURSOR property.

LINKRESULT property

When the command string in the LINK property is executed the result of the operation (as returned from the ShellExecute function) is placed in the LINKRESULT property for further examination if you wish (ShellExecute normally returns a value < 32 if there is a problem executing a command).

SHOWVISITED property

If this property is TRUE the link will be displayed using the VISITEDFORECOLOR property when it has been clicked at least once.

VISITEDFORECOLOR property

This property specifies the color to use for visited links (i.e. those that have been clicked and have a SHOWVISITED property of TRUE).

The GO method

The Hyperlink control also supports a new GO method that executes the contents of the LINK property as though it had been clicked.  The return value from this method is the same as the value returned in the LINKRESULT property.

(Disclaimer: This article is based on preliminary information and may be subject to change in the final release version of OpenInsight 10).

Label controls

Over the past few posts we’ve taken a look at some of the new controls we’ve added to OpenInsight in version 10, but during the development process we’ve also taken the opportunity to upgrade some of the existing controls as well.  In this post we’ll take a look at the humble Label (or STATIC) control and examine some of the new features that have been implemented for it.

Background Images

The Label control now exposes the full Image API in the same way as the version 10 OpenInsight WINDOW object does.

Label control with background image

Label control with background image

Gradient background colors

The BACKCOLOR property now supports gradients in the same way that the current OpenInsight WINDOW object does, along with the associated GRADIENTSTYLE property.

Label control with gradient background

Label control with gradient background

Translucent background

The Label control may use a translucent background via the TRANSLUCENCY property.

Label control with translucent background

Label control with translucent background

Aero Glass support

As part of OpenInsight’s Aero Glass support, transparent labels drawn on glass in Vista and Windows 7 have the recommended “glow effect” enabled to improve readability:

Label controls on Aero Glass

Transparent Label controls on Aero Glass

Text Alignment

Vertical as well as horizontal text alignment is now supported via the TEXTALIGN property:

  • “0” Top-Left
  • “1″ Top-Center
  • “2″ Top-Right
  • “3″ Middle-Left
  • “4″ Centered
  • “5″ Middle-Right
  • “6″ Bottom-Left
  • “7″ Bottom-Center
  • “8″ Bottom-Right
Label control with bottom-center text alignment

Label control with bottom-center text alignment

A TEXTORIGIN property is also exposed that allows you to specify the exact XY position that you wish the text to be drawn at in a similar manner to the standard IMAGEORIGIN property.

Mouse-over support

Label controls can now respond to a mouse-over or “hot” state via the new HOTFORECOLOR, HOTFONT and HOTBACKCOLOR properties.  When set these properties are used in place of their standard counterparts (FORECOLOR, FONT and BACKCOLOR) when the mouse is over the control.

Mouse event support

The following standard events are now exposed for Label controls:

  • CLICK
  • DBLCLK

In addition to this we’ve also provided a new MOUSEOVER event along with a notification flag for when the mouse enters and exits a control (We intend to extend the MOUSEOVER event to cover all OpenInsight controls).

Edge styling

By default normal Windows Label controls actually support a “edge-style” that allows them to have a sunken or etched border, or even display themselves as a single vertical or horizontal etched line.  Although this capability can be used in earlier versions of OpenInsight via raw style-bit manipulation we’ve exposed it fully in Version 10 via the EDGESTYLE property.  This can be one of the following values:

  • “0” – No border
  • “1” – Sunken border
  • “2” – Etched Horizontal line along the top edge
  • “3” – Etched Vertical line along the left edge
  • “4” – Etched Frame
Label control with a sunken border

Label control with a sunken border

Label control with an etched frame

Label control with an etched frame

Text handling

We’ve exposed a couple of new text handling properties: AUTOELLIPSES and WORDWRAP.  The former allows truncated text to be suffixed with the ellipses string  “…”, while the latter allows text to wrap in an effort to avoid truncation where possible.

Label control with AUTOELLIPSES enabled

Label control with AUTOELLIPSES enabled

HTML Text rendering

The Label control now supports simple inline HTML rendering via the boolean DRAWHTML property.  The following tags are currently supported:

  • <b>Bold</b>
  • <i>Italic</i>
  • <u>Underline</u>
  • <strike>Strikeout</strike>
  • <sub>Subscript</sub>
  • <sup>SuperScript</sup>
  • <font>Font</font>
  • <br>

The font tag supports the following attributes:

  • color
  • bgcolor
  • face
  • size
Label control with HTML text rendering

Label control with HTML text rendering

 (As with the aforementioned MOUSEOVER support we’re intending to extend HTML text rendering to other controls where appropriate)

(Disclaimer: This article is based on preliminary information and may be subject to change in the final release version of OpenInsight 10).

The Reflection API

From a tool-developers point of view one of the weaker areas in the Presentation Server has always been the lack of a “reflection API”, i.e. a way to discover what properties, methods and events an object actually supports at runtime.  This in turn has led to creating manual lists and records of object attributes, bringing with it with the inherent difficulty of keeping this information up-to-date as new features are added.

Primarily designed with the new PS-based Form Designer in mind, this shortcoming has been addressed in version 10 with the addition of the following new methods to the SYSTEM object:

  • REFLECT_PROPERTIES
  • REFLECT_METHODS
  • REFLECT_EVENTS

Each of these methods takes a single argument which is the type of object to query:

e.g.

buttonProperties = exec_Method( "SYSTEM", "REFLECT_PROPERTIES", "PUSHBUTTON" )
buttonMethods    = exec_Method( "SYSTEM", "REFLECT_METHODS", "PUSHBUTTON")
buttonEvents     = exec_Method( "SYSTEM", "REFLECT_EVENTS", "PUSHBUTTON" )

Each method in turn returns a dynamic array of information describing the requested attribute type:

  • REFLECT_PROPERTIES returns the name of each property and the type of the data it represents.  It also identifies the context that the property is valid for (Devtime/Runtime/Get/Set).
  • REFLECT_METHODS returns the name of each method, along with a list of arguments the method accepts and the type of data each argument should contain.
  • REFLECT_EVENTS returns the name of each event the object type can raise along with the names and data types of arguments passed to an event handler.

Note that when these methods return the type of data for a property or argument there are some cases where only a broad hint is given – Basic+ is an untyped language so it is not really feasible to accurately describe some types using a simple set of flags – e.g. in the case where an argument is a complex dynamic array containing a variety of other core data types such a strings and numbers.

Whilst aimed mainly at developers who write development tools for OpenInsight, this API may still be of interest for those of you who like to write your own diagnostic and debugging tools – when a new property, method or event is added to the Presentation Server it is clearly exposed thereby reducing the likelihood of it remaining hidden and undocumented.

[Edit: 24 Apr 13 – Call_Method renamed to Exec_Method]

(Disclaimer: This article is based on preliminary information and may be subject to change in the final release version of OpenInsight 10).