Sliders.

Sliders, like scrollbars and spinbuttons, allow a cell value to be changed based on user interaction with a widget on the screen.

Figure 7-50 A slider widget.

The slider widget can be used in two ways: by dragging the 'thumb' or by clicking in the 'channel'. The 'thumb' is the small rectangular element between the two arrow buttons. The 'thumb' can be dragged by placing the mouse pointer over the thumb, clicking and holding with the primary mouse button and then dragging the mouse pointer up or down. The 'channel' is the area between the arrows that is not the 'thumb'. A mouse click with the primary mouse button when the mouse pointer is over the 'channel' will cause the scrollbar to move a 'page'. The motion of the 'thumb' will cause a numeric value to change based on the configuration of the widget, as is explained below.

7.4.6.1. Configuring the properties of the slider

The properties of the slider can be altered with the Properties menu item in the context menu which appears when the mouse cursor is placed over the slider and one of the secondary mouse buttons is pressed.

Sliders have five properties which can be configured: the worksheet cell whose value will be altered by movement of the scrollbar 'thumb', the minimum value when the thumb is at the top of its channel, the maximum value reached when the thumb is at the bottom of its channel, the smallest increment of change, and the page increment which is the change which occurs when the channel is clicked.

Figure 7-51 The configuration dialog for slider properties.

The "Link to:" field allows the user to select a cell that will be changed in response to changes in the state of the widget. A user can type the name of a cell in the text box or may click in the text box to activate it and then click on the worksheet to select the desired cell and Gnumeric will automatically add a reference to the cell.

The other properties can be changed either by typing a new number into the text box or by using the up and down arrows to increment or decrement the width number.