File System UI
Specification
Blayd File System UI is a component and control library for Windows Forms. The component
targets the .Net Framework version 2.0 but is supported on versions 3.0 and 3.5.
The Blayd File System UI library is run time royalty free so developers using one
or more of the components or controls in the library can ship the library with their
application without charge. A developer license is required to use the Blayd File
System UI library at design time but the library can be evaluated free of charge
for a period of 14 days. Whilst in evaluation mode the Blayd File System UI library
is fully functional, however, the library will only operate from within the development
environment.
Product Features
The Blayd File System UI library contains components and controls that provide a
user interface representation of file system devices, folders and files. Developers
can use the components and controls in their Windows Forms applications to easily
display file system information to the user. The data source components, when data
bound to the user interface controls, provide the developer with a significant level
of functionality within the designer and a lot can be achieved without writing any
code.
The library is designed to make it easy for developers to display file system information
when creating user interfaces for applications such as file backup and archive,
file explorers and custom file open or save as dialogs. The library does not provide
any underlying file processing functionality, such as file copy, move, delete, etc.
but it does make it relatively easy to create a user interface that initiates file
processing by, for example, fully supporting folder and file copy and paste and
folder and file drag and drop. The events implemented in the components and controls
allow the developer to write code to react to user initiated actions to, for example,
provide any necessary underlying file processing.
Controls
FolderTreeView Control
The
FolderTreeView control is a specialised extension of
the familiar
TreeView control that fully integrates, through data binding, with
the
FolderList (see below) data source component. The
FolderTreeView control
provides a
DataSource property to enable developers to data bind the control
to any component that implements the
IHierarchicalDataSource interface, which
is also contained in the Blayd File System UI library.
Because the FolderTreeView control extends the existing
TreeView control, all of the features familiar to users of
the TreeView control are inherited by and are therefore
available in the FolderTreeView control. You can, for
example, still display a check box next to each node, as shown in the
figure above on the right.
When using the data binding capability of the FolderTreeView control developers
can create a functional, read only, display of file system data from within the
designer without writing any code.
Developers can specify their own "stock" images for the "virtual" Computer (My Computer
on Windows XP) folder, the various drive types and folders by populating and assigning
an image list to the ImageList property. Choose to use Windows XP, Windows Vista
or your own style of image.
By default, the FolderTreeView control automatically generates a context menu that
is displayed whenever the user right clicks a node in the control. The FolderTreeView
control automatically handles some of the context menu commands such as the Expand |
Collapse, Rename and Refresh commands and
surfaces the other commands such as Cut, Copy, Delete
and Paste as events that can be handled by developers in their own code.
The FolderTreeView control provides an ideal solution for displaying the hierarchical
file system object data provided by the FolderList data source component. However,
because the FolderTreeView control uses the IHierarchicalDataSource interface and
the other hierarchical data interfaces contained in the Blayd File System UI library,
the control can data bind to and display the data of any classes that implement
these interfaces.
FolderDropDownList Control
The
FolderDropDownList control lists and displays a
hierarchical node structure in a way that is similar to the familiar combo box control. The
purpose of the
FolderDropDownList control is to allow the user to specify the path
of a selected node and to facilitate such a selection the control is typically used in conjunction
with another control, such as the
FileListView (see below) control, to provide a
user interface similar to the familiar file open and save as dialogs.
The FolderDropDownList control fully integrates, through data binding, with the
FolderList (see below) data source component. The FolderDropDownList
control provides a DataSource property to enable developers to data bind the
control to any component that implements the IHierarchicalDataSource interface,
which is also contained in the Blayd File System UI library.
When closed the FolderDropDownList control
displays a compact view of the currently selected node, however,
when open, the FolderDropDownList control displays the full path
of the currently selected node and the user can navigate up the
hierarchical path of the selected node, select a level one node or
navigate back to the root node.
When using the data binding capability of the FolderDropDownList control developers
can create a functional display of file system data from within the designer without
writing any code.
Developers can specify their own "stock" images for the "virtual" Computer (My Computer
on Windows XP) folder, the various drive types and folders by populating and assigning
an image list to the Images property. Choose to use Windows XP, Windows Vista or
your own style of image.
The FolderDropDownList control provides an ideal solution for displaying a compact
view of the current, selected, path of the hierarchical file system object data
provided by the FolderList data source component. However, because the
FolderDropDownList control uses the IHierarchicalDataSource
interface and the other hierarchical data interfaces contained in the Blayd File System UI
library, the control can data bind to and display the data of any classes that implement
these interfaces.
FileListView Control
The
FileListView control is a specialised extension of the
familiar
ListView control that fully integrates, through data binding, with
the
FileList (see below) data source component. The
FileListView
control provides a
DataSource property to enable developers to data bind the
control to the
FileList component.
The FileListView control lists and displays the file system objects contained in
a single file system folder. The list may contain the file system objects of the
"virtual" Computer (My Computer on Windows XP) folder, in which case the list will
contain disk drives or the list may contain the file system objects of a conventional
folder, in which case the list will contain sub-folders and/or files.
The FileListView control supports all of views it inherits from the
ListView control but extends the view concept to provide a "drive item"
view for displaying the devices contained in the "virtual" Computer folder and
a "file/folder item" view for displaying the sub-folders and files
contained in a conventional file system folder.
When using the data binding capability of the FileListView control developers can
create a functional, read only, display of file system data from within the designer
without writing any code.
Developers can specify their own "stock" images for the various drive types and
folders by assigning image lists to SmallImages and LargeImages
properties. Choose to use Windows XP, Windows Vista or your own style of image. Developers
can use the same image lists with the FileList component when data binding
and initialize the FileList component to assign the key of the relevant
"stock" image to drive and sub-folder items as they are loaded. The
FileList data source component will populate the image lists with the icons
associated with the file types that it loads, therefore, when data bound to an initialized
FileList component, the FileListView control will automatically
display the image associated with each of the files it displays.
By default, the FileListView control automatically generates the column headers
required for the Details view of both of its own file system specific views i.e.
drive item view and folder/file item view. Developers can customize the automatically
generated column headers or the automatic generation feature can be turned off and
developers can create their own column headers.
By default, the FileListView control automatically generates display groups for
its own drive item view if the operating system supports grouping in ListView controls.
Developers can customize the automatically generated groups or the automatic generation
can be turned off.
By default, the FileListView control automatically generates a context menu that
is displayed when the user right clicks a display item or right clicks in the client
area of the control, different context menu items are displayed for each of the
two right click actions. The FilsListView control automatically handles some of
the context menu commands such as the View and Arrange Icons By
commands and surfaces the other commands such as Cut, Copy,
Delete and Paste as events that can be handled
by developers in their own code.
The FileListView control provides sorting, in all views and both item views, view
switching and the placing of display items in to edit mode from its automatically
generated context menu.
The FileListView control can link to and synchronize with another control, such
as the FolderDropDownList control or the FolderTreeView control
by linking the data source components that the controls are data bound to.
Components
FolderList Component
The
FolderList data source component loads and manages a
hierarchical list of file system folders and provides data binding functionality to user
interface components and controls through its
IHierarchicalDataSource interface
implementation.
The hierarchical list created by the FolderList component descends from a single,
level zero, root node. The root node can be specified as the "virtual" Computer
(My Computer on Windows XP) folder in which case the level one nodes will all be
drives. The root node can also be specified as a specific drive, "C", "D", etc.
in which case the level one nodes will all be folders. The value "System" can also
be specified to instruct the FolderList component to load the drive containing the
operating system as the root node, regardless of its drive letter. The root node
can also be specified as a specific folder, in which case the level one nodes will
all be folders i.e. sub-folders of the root node folder.
The FolderList component supports "on demand" loading of sub-folders.
When sepecified, the component will only load one level of sub-folders, rather than the
entire hierarchy, during the initial load. This technique improves performance and reduces
resource usage when loading the folder hierarchy of large disks with lots of folders.
The FolderList component can be initialized to assign the unselected and selected
image index or image key of the images associated with the user interface control
to which it is data bound. When initialized in this way, the FolderList component
will assign the relevant image value, e.g. local drive, remote drive, CD-DVD drive,
folder, etc. to each of the nodes that it loads and data bound controls such as
the FolderDropDownList and FolderTreeView control will
automatically display the correct image for each type of node.
The FolderList data source component only reads from the file system, it does not
write to or update the file system. However, nodes may be added to or removed from
the hierarchical list managed by the FolderList component and nodes in the list
may be renamed. The FolderList component surfaces list changed events that may be
handled by data bound controls or developer code to perform the required file system
updates.
Although the FolderList data source component is primarily intended to provide file
system data, through data binding, to user interface controls it can be used entirely
from code.
FileList Component
The
FileList data source component loads and manages a list of
the sub-folders and files contained in a file system folder.
The FileItemBindingList provided by the FileList data source
component can be data bound, for example, to the BindingSource component,
the FileListView control and the DataGridView control and
to any other component or control that supports the IListSource interface
and the IBindingList interface.
The FileList data source component can be linked, as a child data source, to any
component that implements the IHierarchicalDataSource interface, such as, for example,
the FolderList data source. When linked to another data source component,
the FileList component notifies the linked data source when its list changes
and it handles the events raised by the linked data source so that it can react when the
linked data source's list changes.
The AssociatedImages and AssociatedLargeImages properties can
be used to specify image lists which the FileList component will populate with the
small and large image associated with each file type that it loads. Controls, such as
the FileListView, that are data bound to the FileList component
can use the same image lists and the images they contain when displaying the list items.
The FileList component can be initialized to assign the image key of the drive type
and folder images contained in the image lists reference by the AssociatedImages
and AssociatedLargeImages properties. When initialized in this way,
the FileList component will assign the relevant image value, e.g. local drive,
remote drive, CD-DVD drive, folder, etc. to each of the file items that it loads and data bound
controls such as the FileListView control will automatically display the correct
image for each type of file item.
ChooseDetailsDialog Component
The
ChooseDetailsDialog component provides a dialog
box in which the user can select, reorder and resize the column headers for an associated
instance of the
FileListView control. The
FileListView control
displays column headers when its
View property is set to
Details. Developers can use the
ChooseDetailsDialog component to
display a dialog that allows the user to edit the column header settings.
When the FileListView control's AutoGenerateContextMenu property
is set to true, the control uses the ChooseDetailsDialog to automatically display
the "Choose Details" dialog from the relevant option on its context menu. However,
developers that are not using the automatic context menu generation feature can use
the ChooseDetailsDialog directly from their own code to display the
"Choose Details" dialog.
When the ChooseDetailsDialog component is associated with an instance of the
FileListView control, the settings made by the user in the dialog will
automatically be used to update the FileListView control when the user
clicks the OK button.
The ChooseDetailsDialog component can be associated with an instance of the
FileListView control by setting the ViewControl property
or by passing an instance of the control to the relevant ShowDialog method overload.