cConsolePanel class

A rectangle of the console with a border, a title and padding, that draws its border into a cConsoleBuffer and tells where its content area is.

A panel holds a position, a size and a few style fields, and draws nothing until Render is called with a buffer. It does not hold content: the program writes into the area that ContentRect returns. The panel takes the buffer to draw into as a parameter and holds no console. cConsoleLayout creates panels and keeps them by name.

Dim panel As cConsolePanel = New cConsolePanel("main", 2, 1, 20, 6)
Dim buf As cConsoleBuffer = New cConsoleBuffer(30, 10)
Dim ci As ConsoleCharInfo

panel.Title = "Log"
panel.BorderStyle = PanelBorderStyle.Double
panel.Render buf, ConsoleColor.Cyan, ConsoleColor.Black

ci = buf.GetChar(2, 1)                      ' the upper left corner
Debug.Print Hex$(AscW(ci.Char)) & " " & ci.ForeColor
ci = buf.GetChar(4, 1)                      ' the first character of the title
Debug.Print ci.Char & " " & ci.ForeColor
Debug.Print panel.ContentWidth() & " " & panel.ContentHeight()
' Output:
' 2554 11
' L 15
' 16 2

In the syntax lines of this page, object is a cConsolePanel. Columns and rows are counted from 0 in the buffer.

The rectangle and the content area

Rect is the rectangle of the panel with its edges inclusive: a panel at column 2, row 1, 20 columns wide and 6 rows high has Rect.Left 2, Rect.Top 1, Rect.Right 21 and Rect.Bottom 6. The border is drawn on the edge cells.

The content area is what is left inside. ContentRect takes one cell from each side for the border, unless BorderStyle is None, and then Padding cells from each side. The sample above has a content area of 16 columns by 2 rows, from column 4, row 3 to column 19, row 4. The content area can be empty or have a negative size when the panel is small.

Fields

The class has seven public fields, not properties. They are read and written as panel.Title, and a write takes effect at the next Render.

BorderColor

The colour of the two spaces that surround the title on the top border. A ConsoleColor. The starting value is Gray.

The border itself is drawn in the colours that are passed to Render, and not in this one.

BorderStyle

The border style. A PanelBorderStyle. The starting value is Single.

Name

The name of the panel. String. The constructor sets it. cConsoleLayout keeps its own list of names, so changing this field later does not change the name under which the layout finds the panel.

Padding

The number of cells between the border and the content area, on every side. Long. The starting value is 1.

Rect

The rectangle of the panel. A ConsoleRect, with inclusive edges. The constructor, Move and Resize set it. A program that references the published package TBMANLIB_ConsoleCore cannot read its fields: see The two packages. ContentWidth and ContentHeight give sizes as Long values.

Title

The text on the top border. String. The starting value is an empty string, which draws no title.

Render writes a space, the title and a space, from column Rect.Left + 1, in the row Rect.Top. A title longer than Rect.Right - Rect.Left - 3 characters is cut, without an ellipsis, and a panel that is too narrow for one character draws no title. The title is drawn on a black background.

TitleColor

The colour of the title text. A ConsoleColor. The starting value is White.

Enumeration

PanelBorderStyle

The border style of a panel. The enumeration is declared in the class, and its members are written without the class, as in PanelBorderStyle.Rounded; the type is cConsolePanel.PanelBorderStyle or PanelBorderStyle.

Member Value Border
None 0 No border, and no title. The content area starts at the edge plus the padding.
Single 1 Single lines: U+250C, U+2510, U+2514, U+2518, U+2500, U+2502. The default.
Double 2 Double lines: U+2554, U+2557, U+255A, U+255D, U+2550, U+2551.
Rounded 3 Single lines with rounded corners: U+256D, U+256E, U+2570, U+256F, with U+2500 and U+2502.
Bold 4 Heavy lines: U+250F, U+2513, U+2517, U+251B, U+2501, U+2503.

Single and Double are drawn by DrawBox of the buffer, and the other two by the panel itself.

Constructor

New

Creates a panel.

Syntax: New cConsolePanel [ ( [ name [ , left [ , top [ , width [ , height ] ] ] ] ] ) ]

name
optional A String. The default is an empty string.
left, top
optional Long values, the position of the upper left corner. The defaults are 0.
width, height
optional Long values, the size in columns and rows. The defaults are 10 and 5.

Sets Rect to left, top, left + width - 1 and top + height - 1, BorderStyle to Single, BorderColor to Gray, TitleColor to White and Padding to 1.

Methods

ClearContent

Fills the content area with spaces.

Syntax: object.ClearContent ( buffer [ , fore [ , back ] ] )

buffer
required A cConsoleBuffer.
fore
optional A ConsoleColor, the colour of the cells. The default is Gray.
back
optional A ConsoleColor, the background. The default is Black.

The padding and the border are left as they are. Nothing is done when the content area is less than 2 cells wide or 2 cells high.

ContentHeight

Returns the height of the content area.

Syntax: object.ContentHeight ( ) As Long

Returns ContentRect.Bottom - ContentRect.Top + 1. It is 0 or negative when the border and the padding take all the rows.

ContentRect

Returns the content area.

Syntax: object.ContentRect ( ) As ConsoleRect

Returns a ConsoleRect that is Rect less one cell on each side for the border (none when BorderStyle is None) and less Padding cells on each side.

ContentWidth

Returns the width of the content area.

Syntax: object.ContentWidth ( ) As Long

Returns ContentRect.Right - ContentRect.Left + 1.

Move

Moves the panel and keeps its size.

Syntax: object.Move ( left , top )

left, top
required Long values, the new position of the upper left corner.

Nothing is drawn, and the old cells are not cleared.

Render

Draws the border and the title.

Syntax: object.Render ( buffer [ , fore [ , back ] ] )

buffer
required A cConsoleBuffer.
fore
optional A ConsoleColor, the colour of the border. The default is Gray. BorderColor is not used for it.
back
optional A ConsoleColor, the background of the border. The default is Black.

Draws the border of the style in BorderStyle around Rect and then the Title. The inside of the panel is not changed: the text that was there stays, and ClearContent removes it. With the style None the method draws nothing, not even the title. Cells outside the buffer are dropped.

Resize

Gives the panel a new size and keeps its position.

Syntax: object.Resize ( width , height )

width, height
required Long values, the new size in columns and rows.

Sets Rect.Right to Rect.Left + width - 1 and Rect.Bottom to Rect.Top + height - 1. Nothing is drawn.

See Also