By using the precise selection window, you can control exactly what rectangular or square area is selected. Click on the Floodfill tool to select it. In the Fill Style choose Pattern. Leave the rest of the values as is for the defaults. Click on the pattern tab in the floodfill tool control box to select the pattern.
Flood fill the selected button area with the texture.
Leave the button area selected. Call it Color. Click on the Floodfill tool to select it. In the Fill Style choose Solid Color. Leave the rest of the values as is for the defaults.