Image Bar Widget (ImageBar.class)

The Image Bar Widget uses two images (empty bar and full bar) to create a custom "bargraph". A byte (or word) returned from a function call is the widget input. Based upon the value of the byte (or word) returned, a percentage of the empty bar and a percentage of the full bar are displayed. For further customization, the wipe between empty and full can be from left-to-right, right-to-left, bottom-to-top, or top-to-bottom. When the minimum value is returned, the entire "empty" image is displayed. When the maximum value is returned, the entire "full" image is displayed.

Image Bar Parameter Attributes:

Parameter="invisible" value="CHECKED" or "UNCHECKED" — Specifies if the Image Bar is to start out invisible or not. If the attribute is UNCHECKED, then by default the Image Bar is visible. If the Image Bar starts out invisible, the only way to make it visible again is via the IWC method reappear().

Parameter="empty" value="image" — Image used when minimum value is returned from the href function. Image file must be of type .GIF, .JPG, or .PNG.

Parameter="full" value="image" — Image used when maximum value is returned from the href function. Image file must be of type .GIF, .JPG, or .PNG. Parameter="href" value="function" — The function called to retrieve the widget input. See Appendix B for all available functions for the Image Bar widget. The function is called at an update rate specified by the updateRate attribute.

Parameter="max" value="number" — Maximum value returned from the href function; must be greater than min. If the function returns a byte, the range is 1 - 255 (0x01 - 0xFF). If the function returns a word, the range is 1 - 65535 (0x01 - 0xFFFF).

Parameter="min" value="number" — Minimum value returned from the href function; must be less than max. If the function returns a byte, the range is 0 - 254 (0x00 - 0xFE). If the function returns a word, the range is 0 - 65534 (0x00 - 0xFFFE).

Parameter="sweepFrom" value="LEFT" or "RIGHT" or "TOP" or "BOTTOM" — Determines where (within the image bar cell) to begin the image transition. The options are:

• LEFT — The "full" and "empty" images transition from left-to-right.
• RIGHT — The "full" and "empty" images transition from right-to-left.
• TOP — The "full" and "empty" images transition from top-to-bottom.
• BOTTOM — The "full" and "empty" images transition from bottom-to-top.

Parameter="updateFreq" value ="number" — Specifies the href function call frequency (specified in seconds, with a single floating-point number). The range is 0.00 - 655.35. A value of 0.00 means update never.

Parameter="updateDelay" value ="number" — Specifies the delay time from when the page is loaded until the first href function call (specified in seconds, with a single floating-point number). The range is 0.00 - 655.35. If this number is not specified, then the delay time defaults to the updateFreq number.

Optional Image Bar Parameter Attributes:

Parameter="waitForInit" value="CHECKED" or "UNCHECKED" — Only valid if href is used. Specifies if the Image Bar will wait for valid data before displaying an image on the channel. If CHECKED, the Image Bar will not display until the data from the href function is received. If UNCHECKED, or the attribute is not present, the Image Bar momentarily starts at the min location until the href function receives its data. If waitForInit not specified, the default is UNCHECKED.