Slider
The Slider () is a form object for choosing a numerical input using a slider control. Enter the name of the slider object in the Name field.
From the Value type list, choose Integer or Real (the default), depending on the type of data in the data source for the slider.
In the Minimum value (default: 0) and Maximum value (default: 1) fields, enter the minimum and maximum values that define the range of the data covered by the slider.
Enter the number of steps (resolution) for the slider in the Number of steps field (default: 5).
From the Orientation list, choose Horizontal (the default) or Vertical to change the slider orientation from horizontal to vertical or vice versa.
In the Tooltip field, enter text that will appear as a tooltip when the user hovers the pointer over the slider.
You can append a unit to the number for the slider’s value by selecting the Append unit to number check box and typing a unit in the associated text field. Units are only applicable to sources that are string declarations and parameters.
In addition, the Settings window contains the following sections.
Source
In this section, you define the variable to use as the data source for the slider. The section contains a tree with a filtered view of the trees in the Application Builder and Model Builder windows. The nodes either represent some sort of data or have children that do. For a slider, you can use a scalar value from a variable in the model or a variable defined under Declarations. To extend the list of available data nodes, click the Switch to Model Builder and Activate Data Access button () in the Source section header, which takes you to the Model Builder, and then select a node in the Model Builder branch whose data you want to access. With this button active, the Settings window of the selected node displays a Select Data Source check box (a green square) next to the settings that you can include. Click to select the check box to include that data as an available source node for sliders.
When you select a node that represents data, the Use as Source toolbar button () below the tree is enabled. You can click it or, alternatively, press Enter, double-click, or right-click the node and choose Use as Source to add it as the selected source. You can also click the Create New Declaration and Use It as Source button () or the Create New Form Declaration and Use It as Source button () in the Source section header to create a new global or local (in the form) variable declaration for the slider and use it as the source. A Create and Use Declaration dialog box opens so that you can select the data type of the source (if applicable), its name, and its initial value (if applicable). The name cannot be in conflict with any existing variable declaration. Click the Edit Node toolbar button () below the tree to move to the corresponding node. If necessary, the program switches to the Model Builder.
After selecting a node as the source, the node appears as the selected source under Selected source.
If you try to use the same data source in several form objects, you may encounter some strange side effects. The initial value for the source may not be what you expect. You may also experience serious errors if the initial value of one form object is invalid for one of the other form objects.
From the Initial value list, select From data source to use the value specified by the selected data source, or select Custom value to enter the initial value (starting value) for the slider (default: 0) in the Value field below. Typically, the initial value and the minimum value are the same.
Unit
From the Method list, select one of the following methods to specify the unit for the slider:
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No unit, the default option.
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Append unit to number: The unit that you type in the Unit expression field is appended to the number corresponding to the slider’s position.
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Append unit from unit set: The slider appends a unit from a Unit Set node added under Declarations (see The Unit Set Node). You specify the unit set to use from the Unit set list and the unit to use from Unit list, which lists all defined properties and their units from the select unit tests. There is also a No unit option.
Appearance
Under Appearance, you can control the initial state of the slider when users run the application. By default, the slider is visible and enabled. Clear the Visible or Enabled check box if you want to make the initial state so that the slider is hidden or unavailable. You can then make it visible or enable it using a method. In the Form Editor, the state of the form object is indicated by a change in its appearance. Objects that are hidden become visible when selected in the Form Editor.
Position and Size
This section contains all of the layout settings for a slider in the grid of the parent form.
In the grid mode, you can control the horizontal and vertical alignment of the slider using the following lists:
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From the Horizontal alignment list, choose Left, Center, Right, or Fill, which automatically expands the form object to fill the cell in the horizontal or vertical direction (where applicable).
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From the Vertical alignment list, choose Middle, Top, Bottom, or Fill, which automatically expands the form object to fill the cell in the horizontal or vertical direction (where applicable).
The need to specify the alignment is most obvious when working in the grid mode, as it controls how the form object is aligned in its grid cell. Aligning the form object can be useful in the sketch mode too, and you can then use the alignment tools on the Arrange menu in the Form toolbar’s Sketch section. When running the application in any client other than the Windows client, the form objects may not be positioned exactly as seen in the form windows. This is because the form objects may have a different size in other clients, giving them a slightly different positioning. Specifying the alignment ensures that the form objects are aligned as you want them to be in all clients.
You can also specify the width of the slider. Enter a width (in points) in the Width field. If you have chosen Fill from the Horizontal alignment list, you can instead specify a Minimum width. Choose Automatic to compute the minimum width automatically (typically, this means a minimum size of 0) or choose Manual to specify a minimum width in the text field underneath. The Height field is unavailable because the height of the slider is determined by the software.
Additionally, in the sketch mode, you can specify the absolute position of the slider using the Position x and Position y fields. In the grid mode, you can position the object in the grid and see the grid position as the Row, Column, Row span, and Column span values.
The form windows update these size and positioning settings through the draw operations performed there, such as resizing and moving the object.
Cell Margin
Under Cell margin (in grid mode only), you can control the margins around the slider. By default, the margins are taken from the parent form. From the Cell margin list, choose:
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None, for no margin around the slider.
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From parent form (the default), to use the margins set for the parent form.
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Custom, to specify the margins for the slider in the Horizontal and Vertical text fields.
Events
You can specify a method or command sequence that the application runs when the slider has been moved. The On data change list contains None (the default) and any available methods or command sequence. You can add the following types of events by choosing from the Create Global Method menu () to the right of the On data change list:
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Choose Create Global Method () to create a global method. Type the name of the global method in the Name field of the Create Global Method dialog box that opens and then click OK. The global method is then added under Methods, and its Method Editor window opens.
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Choose Create Form Method () to create a form method. Type the name of the form method in the Name field of the Create Form Method dialog box that opens and then click OK. The form method is then added under the Methods node under the Form node, and its Method Editor window opens.
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Choose Create Local Method () to create a local method. Its Method Editor window opens.
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Choose Create Command Sequence () to create a command sequence using the Create Command Sequence dialog box that opens. There you can choose commands from the available Forms, GUI Commands, Declarations, Form Declarations, Methods, Form Methods, Libraries, and Model folders. To add a command, right-click the desired command node and choose the command to use (Run, for example). The command then appears in the list of commands below. You can edit that command sequence using the toolbar buttons for moving and deleting commands below the table. Click the Convert to Method button () and choose Convert to Method or Convert to Form Method to convert the command sequence to a method. Click the Go to Method button () below the table to select the method in the Application Builder tree and open the method in a Method Editor window. For commands that include arguments, click the Edit Argument button () to choose an argument in the Edit Argument dialog box that opens.
There can only be one local method and one command sequence so if you add one or both of them, the menu will instead contain Remove Local Method () and Remove Command Sequence (), respectively. Click one of them to delete the local method or command sequence.
The selected method in the On data change list then changes to the created method or command sequence. You can also Ctrl+Alt-click the slider object or right-click it to create a local method or (by choosing Edit Method or Edit Local Method) to open the method associated with the command. To open the selected method or command sequence, click the Go to Source button (). The focus then moves to the method’s editor window or the Command Sequence dialog box, respectively.
For events triggered by data change, the event is triggered after the new data value is stored in the data source.
By default, the Trigger while dragging check box is selected. The event is then triggered while dragging the slider. If the method that is connected to the event takes some time to run, the slider can appear to be sluggish. If you clear the Trigger while dragging check box, the event is instead only triggered when you stop dragging and release the slider.
If you select more than one form object and they all support the On data change event, you can specify a method to, for example, make them inform users that plots and outputs are invalid.