Using Tables to Control the Layout of Elements

When using tables (nUITableElement objects) for element layout, you need to consider the table’s inner padding and the cell spacing within a table. Additionally, table cells (nUITablecellElement objects) also have inner padding. You control inner padding and spacing using the following attributes.

NativeUI Object	Attribute	Description
Table (nUITableElement object)	InnerX	Defines the distance from the table’s left edge to where table cells are drawn.
	InnerY	Defines the distance from the table’s top edge to where table cells are drawn.
	InnerWidth	Defines the table’s usable width in which you can add content.
	InnerHeight	Defines the table’s usable height in which you can add content.
	cellSpacingWidth	Defines the distance between the table columns.
	cellSpacingHeight	Defines the distance between table rows.
Table cell (nUITablecellElement object)	InnerX	Defines the distance from a cell’s left edge to where child elements are drawn.
Table cell (nUITablecellElement object)	InnerY	Defines the distance from a cell’s left edge to where child elements are drawn.
	InnerWidth	Defines a cell’s usable width in which you can add content.
	InnerHeight	Defines a cell’s usable height in which you can add content.

The use of InnerX, InnerY, InnerWidth, and InnerHeight attributes in tables and table cells is the same as for any parent object. For more information, see Controlling the Inner Padding of Parent Objects.

You can set the background color and Image of tables (nUITableElement objects), table rows, (nUITablerowElement objects), and table cells (nUITablecellElement objects). Additionally, you can add borders around the cells in a table. You control background colors, Images and borders using the following attributes.

NativeUI Object	Attribute	Description
Table (nUITableElement object)	Bgcolor	Defines the background color for the entire table.
	BackgroundDrawable	Defines the background color or Image for the entire table.
	CellBorderColor	Defines the color for the borders drawn around the cells in the table.
	CellBorderThickness	Defines the width of the borders drawn around the cells in the table. Specify a pixel value for the width. If you do not want the cells to have a border, specify 0 (zero).
Table row (nUITablerowElement object)	Bgcolor	Defines the background color for an entire row.
	BackgroundDrawable	Defines the background color or Image for an entire row.
Table cell (nUITablecellElement object)	Bgcolor	Defines the background color for a cell.
	BackgroundDrawable	Defines the background color or Image for a cell.

For row 2, the background color for the row is not set. As a result, the table background color displays for the row. Cells 1 and 3 in row 2 have a background color set to blue. The background color is not set for the cell 2 in row 2, so it takes on the background color of the table.

When you add a table (nUITableElement object) to a parent object, the table uses the full width available in the parent object. The following describes how columns, rows, cells, and elements are sized.

For columns, you specify the relative column width sizes when using the constructor to create a nUITableElement object. For example, if you specify 1, 2, 1, the constructor creates a table with 3 columns where column 1 and 3 are half the size of column 2. In other words, column 1 uses 25% of the table width, column 2 uses 50% of the table width, and column 3 uses the remaining 25%.

For table rows (nUITablerowElement objects), by default, the height of a row is determined by the height of the cells that the row contains. If you want, you can set the Height attribute of a nUITablerowElement object to specify a pixel value to use for the row height. However, if the cells in the table are larger than the pixel value you specify, the content is clipped.

Cell width is determined by the size of the column in which the cell resides, and also taking into consideration the column spacing, which is the gap between columns in the table. The column spacing is set using the CellSpacingWidth attribute of the nUITableElement object.

Cell height, by default, is determined by the height of the cell’s contents and inner padding. If you want, you can set the Height attribute of a nUITablecellElement object to specify a pixel value to use for the cell height. However, if the contents of a cell is larger than the pixel value you specify, the content is clipped.

You can span table cells both horizontally or vertically. To span cells horizontally, use the Hspan attribute of the nUITablecellElement object. To span cells vertically, use the Vspan attribute of the nUITablecellElement object.

For elements that you place in table cells, the element width and height is determined the same as placing the elements in any parent object. For more information, see Sizing Child Elements.

When an application adds elements into a table cell, the elements are positioned vertically, one below the other, starting at the top of the table cell. The elements are indented based on the table cell’s inner padding. You can control the spacing between elements in a table cell the same as you control vertical spacing for any parent object. For more information, see Controlling the Vertical Spacing Between Child Elements.

You can leave cells empty. For example, an application might use a single row table with column widths set to 25%, 50%, 25% of the table width. To have a button that is 50% the size of the table width display in the center of the screen, the application can place the button in the center cell, leaving the outer cells empty.

You can use the VAlign attribute of the nUITablecellElement object to vertically align the contents of a cell. This is useful when tables contain cells that are vertically spanned, and also when the elements in table cells can potentially be of different heights (images, text, buttons, etc.). The VAlign attribute allows applications to vertically align elements in a manner that looks good on the device.