You can control the appearance of objects by assigning the colors from the Colors palette. To display the palette use the correspondent Colors option from the Object Information panel. You can control the colors of the object border, object fill, gradient, shadow, text, barcode, and image tint color.
 

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To change the color of the text in a rectangular object, or a color of a BARCODE object, switch to the Text Info tab of the Object Information panel, click on the color control to display the Color palette, and, and select the desirable color.

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