![[image of a LineScale]](LineScale.png)
Here is an example of a grade bar with range from 0.0 to 10.0 with one decimal and labelled ticks:
The line scale component has the same base component as the GradeBar many of the parameters are the same.
First, the following parameters are special to the line scale component only:
| Parameter | Value | Description | R/O |
|---|---|---|---|
| class | LineScale | Class alias for a line scale component. | Req. |
| ticks | choice format string | Set ticks and optionally labels to line positions corresponding to a grade. | Opt. |
| labelfont | font name | The font used for tick labels. | Opt. |
| sliderOffset | pixels | The offset from the component's left and right edge to the start of the grading line. | Opt. |
| knobSize | pixels | The size of the slider knob. Default is 10. Larger values can be used if knob is too small for screen. Changing knob size also changes the thickness of the slider's line. | Opt. |
| answerWhen | moved or released | Whether to send an answer events when subjects is dragging the knob (moved) or just when the mouse button is released (released). Default is moved (to behave the same as the GradeBar). | Opt. |
| lineLength | pixels | The minimum length of the slider line. If not set, it is calculated automatically based on other components on the answering panel. (The total width of the component is at least lineLength + 2 * sliderOffset). | Opt. |
The rest of the parameters are the same as in GradeBar. However, some parameters have different default values for the LineScale than to the GradeBar.
| Parameter | Value | Description | R/O |
|---|---|---|---|
| question | text | The question shown to subject. | Req. |
| minimum | number | The minimum of the scale. Default is 0.0. | Opt. |
| maximum | number | The maximum of the scale. Default is 5.0. | Opt. |
| decimals | number of decimals | Number of decimals in the grade. Default is 1. | Opt. |
| questionfont | font name | The font used for question text. | Opt. |
| showValue | true or false | Whether to show the current value numerically to the subject. In line scale, the default is false. | Opt. |
| showLabels | true or false | Whether to show the adjectives to the subject. In line scale, the default is false. | Opt. |
| choiceformat | choice format string | Give adjectives to certain ranges of values. Default is no adjectives. This is different from the ticks and tick labels. | Opt. |
| defaultAnswer | number | Set the initial value (and the position) of the grade when
the question is initialized or reset. A special value
'random' can be used to initialize the value with a
new random number every time the component is reset. If this
option is left out, the default answer is the midpoint of the
minimum and maximum of the scale.
| Opt. |
The following example should help you to make your own ticks. It produces the ticks shown in the LineScale picture above.
# Set ticks and labels qA.ticks=0.0#Very Lo-Fi|2.5/1#Rather Lo-Fi|5.0#Midway|7.5/1#Rather Hi-Fi|10.0#Very Hi-Fi
The first tick is placed at the position on the line that corresponds to the grade 0.0. Label 'Very Lo-Fi' is also assigned to that tick.
The second tick is placed to the position that corresponds to the grade 2.5 with a label 'Rather Lo-Fi'. The label is also placed one line below the first label. Larger numbers (1, 2, 3, 4, etc.) can also be used to place the label more lower. This is helpful if there are many labels and they would overlap.
If a tick without a label is wanted, just leave out the '#label' off (for example, '1.0|2.0|3.0' would place three ticks without labels).
Any number of labels and ticks can be added at any place of the line (except outside the range of the line).