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CyDAS General Controls: Class ImageMapControl

The class ImageMapControl provides a click sensitive map for windows desktop applications. For more information on its deployment, see overview of the image map.

Overview

Constructors
Interfaces
Enumerations
Properties
Methods
Events
Interaction with other classes
Internal Processing


ImageMapControl
New()

AutoNavigate: Boolean
AutoSize: Boolean
Bitmap: System.Drawing.Bitmap {readonly}
Data: ImageMapData

AreaSelected(ByRef sender As Object, ByRef e As ImageMapAreaSelectedEventArgs)

Programming Language

Microsoft Visual Basic .Net.

Availability

Copyrighted but free software under the GNU Public License.
Binaries and source code can be obtained from the Download section.

Constructors

Public Sub New()

Instantiates a new ImageMapControl object. There are no parameters for this function. The constructor call and
its coding will normally happen automatically within the windows form designer.

Interfaces

Inherits

System.Windows.Forms.UserControl

Enumerations

The class does not provide enumerations.

Properties

AutoNavigate As Boolean

Determines if the control will executed the command given in the Command property of a clicked ImageMapArea automatically or instead raise an AreaSelected event.

Property Value

true, if the control automatically executes the command linked to an area when it is clicked;
false, if the control raises an AreaSelected event instead.

Remarks

The commands are evaluated by "System.Diagnostics.Process.Start". Exceptions occuring when opening the application are suppressed.
The default value is true.
In the designer, the property is listed in the section "Behavior".

AutoSize As Boolean

Determines if the control is resized to fit the size of the image.

Property Value

true, if the control automatically adjusts to the image.
false, otherwise.

Remarks

If false, the image will be resized to fit the control.
Its height to width relation is not preserved but adjusted to the control.
There is no need to recalculate the coordinates of the area elements of the map, the coordinates will be internally re-transformed.
The default value is true.
In the designer, the property is listed in the section "Behavior".

ReadOnly Property Bitmap As System.Drawing.Bitmap

Gets the bitmap associated with the image map data.

Property Value

the bitmap associated with the image map data.

Remarks

This property is a short cut to Data.Batmap.
It is read-only because changing of the bitmap after setting the Data property could lead to unpredicatable behavior.

Data As ImageMapData

An ImageMapData object describing the image map including its image and its area elements.

Property Value

an ImageMapData object describing the image map

Remarks

Changing the property value causes the control to refresh.
Depending on the AutoSize property, it may also be resized.
It is advisable not to exchange the Bitmap of the ImageMapData object later because some internal values are calculated from the contained bitmap when the Data property is set. Unexpected behavior could be caused.
The property cannot be accessed in the designer.

Methods

The class does not provide public methods.

Events

AreaSelected(ByRef sender As Object, ByRef e As ImageMapAreaSelectedEventArgs)

Occurs when an area of the image map was clicked and the AutoNavigate property of the ImageMapControl is set to false.

Parameters

sender: this instance of Multi-Select-Combobox Control
e: the ImageMapAreaSelectedEventArgs contain a reference to the ImageMapArea object representing the clicked area.

Remarks

The event is not raised when the AutoNavigate property is set to true.
This is the default event of the ImageMapControl.

Interaction with other classes

Classes used by ImageMapControl

The ImageMapData class is the central data container of the ImageMapControl.

Internal Processing

ImageMapControl_Click(...) Handles MyBase.Click

If the image map is clicked, the control determines the mouse position and, if AutoSize is false, calculates the position in the original image map. Thereafter, the control inquires from the Data property the clicked ImageMapArea object (ImageMapData.getSelectedArea()).

If an area was found for this position, the next steps depend on the AutoNavigate property. If it is false, the control will raise an AreaSelected event. Otherwise, it will have windows evaluate the Command property of the area element and start the appropriate program; errors occuring during this windows processing are suppressed.

ImageMapControl_MouseMove(...) Handles MyBase.MouseMove

If the mouse is positioned over the image map, the control determines the mouse position and, if AutoSize is false, calculates the position in the original image map. Thereafter, the control inquires from the Data property the clicked ImageMapArea object (ImageMapData.getSelectedArea()).

If an area was found for this position, the tooltip text of the control is set to the Title property of the area. Otherwise, the tooltip is removed.