Adding an Application Bar to your Windows Phone 7 application
http://www.nickharris.net/2010/04/adding-an-application-bar-to-your-windows-phone-7-application/
Icon Buttons UI Best Practices
- Icon images should use a white foreground on a transparent background using an alpha channel. The Application Bar will colorize the icon according to the current style settings and colored icons can cause this effect to display unpredictably.
- The circle displayed on each Icon Button is drawn by the Application Bar and should not be included in the source image.
- Icon images should be 48 x 48 pixels in size. The white foreground graphic for the button should fit in a 26 x 26 area square in the center of the image so that it does not overlap the circle.
- Do not use an Icon Button for a back button that navigates backwards in the page stack. Windows Phones are required to have a dedicated hardware back button that should always be used for backward navigation.
- Use Icon Buttons for the primary, most-used actions in your menu. Some actions are difficult to convey with an icon. If this is the case, you should using a Menu Item instead.
- Choose icons that have clear meanings when the Application Bar is rotated. The Application Bar automatically handles changes in screen orientation. When the device is in a landscape orientation, the menu is displayed vertically on the side of the screen. The icon buttons are rotated so that they appear upright to the user, but the order of the icons in the list is not changed. It is possible for icon meanings to be confused when this occurs, particularly if two of the icons are mirror images of each other along the Y axis.
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