Windows Forms Programming with C# by Unknown

Author:Unknown
Language: eng
Format: epub

Figure 10.8

This figure shows the various measurements used to calculate a list item’s

width and height.

The following steps implement the code required for the MeasureItem event. Fig-

ure 10.8 illustrates the various measurements used to determine the width and height

of the item.

CALCULATE THE LIST ITEM SIZE DYNAMICALLY

Action

Result

1

In the MainForm.cs window, add

private static Rectangle _drawRect

a static Rectangle to the

= new Rectangle(0,0,45,45);

MainForm class to hold the

drawing rectangle for the image.

2

Add a MeasureItem event

private void lstPhotos_MeasureItem

handler for the lstPhotos list

(object sender,

Windows.Forms.MeasureItemEventArgs e)

box.

{

3

Calculate the size of the image

Photograph p = _album[e.Index];

when scaled into the drawing

Rectangle scaledRect

= p.ScaleToFit(_drawRect);

rectangle.

4

Calculate the item’s height.

e.ItemHeight = Math.Max(scaledRect.Height,

lstPhotos.Font.Height) + 2;

5

Calculate the item’s width.

e.ItemWidth = scaledRect.Width + 2

+ (int) e.Graphics.MeasureString(

p.Caption, lstPhotos.Font).Width;

}

For the item’s height, this code uses the larger of the scaled item’s height and the

ListBox control’s font height, plus 2 pixels as padding between subsequent items in

the list.

e.ItemHeight = Math.Max(scaledRect.Height, lstPhotos.Font.Height) + 2;

For the item’s width, the width of the scaled image plus the width of the drawn string

is used, plus 2 pixels as padding between the image and the text. To do this, the

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