Radial Indicator
A radial indicator is used to show values on a round meter. An example, created with the default values, is shown here:
As shown, the outer arc and vertical division line are visible only while in design mode. Their purpose is to help you scale and place the indicator and will vanish when the application is put into run mode. The needle will remain and can be any image you wish.
The following image shows the default Graphic Editor dialog for the radial indicator.
(Click title to expand text)
The source of the value being indicated. This can be any of:
Constant – useful only for testing.
Expression – create a meter that shows a value calculated from several I/O tags.
Tag – select an I/O tag whose value will be displayed by the meter.
Parameter – choose a parameter from the page where this meter is being drawn. When the parameter option is selected, the data source display will be replaced by a drop-down selector, showing all of the page parameters that are of type Tag.
The image used for the indicator. The meter parts group of the graphic library includes several images of radial indicators. The reference point will always be at the bottom center of the image. For those that include a pivot, part way along the image (example following) you can add an offset from center.
Some needle images are designed to look like they pivot on a mid-point. Since all needles actually pivot on the bottom, center of the bitmap, you may need to add a negative offset before the image pivots about a point that looks natural.
When checked, the needle will move in a counter-clockwise direction to indicate increasing values.
If set, the needle's motion will be animated to move smoothly to position rather than jumping directly to the new value.
Sets the starting angle of the needle display (left side). Measured in degrees, clockwise from vertical. Defaults to 225 degrees.
Sets the end angle of the needle display (right side). Measured in degrees, clockwise from vertical. Defaults to 135 degrees.
Adjusts the hue, etc. of the indicator image. Color control is described in the chapter: Color Options - Adjust Image Hue.
Whether to use the tag's scaling values or to set a range directly in the indicator using the minimum and the maximum value fields.