Slider

GnosisUIElementSlider is a control element (elementId = "Slider") for numeric range input.

It inherits GnosisUIElementControl, so it also uses control identity fields (viewId, controlIdMode, controlId) configured on the component.

Runtime parameters

In addition to built-in element parameters, GnosisUIElementSlider supports:

direction (string) - one of: LeftToRight, RightToLeft, BottomToTop, TopToBottom
minValue (float)
maxValue (float)
wholeNumbers (bool)
value (float)
onValueChangedInvokes (list) - list of service invokes to execute on slider value changes.
- each item shape: { service, function, parameters? }
- runtime adds/updates value on the invoke payload before calling the function

Example - create a slider under a view

GameUI.CreateSlider.Example.cs


private GnosisFunctionResult CreateMasterVolumeSlider()
{
    if (Context?.Store == null || Context.CallService == null)
        return GnosisFunctionResult.Fail("No context");
 
    var payload = GnosisNode.CreateObject(Context.Store);
    payload.Set("elementId", "Slider");
    payload.Set("parentId", "ui.SettingsView");
 
    var parameters = GnosisNode.CreateObject(Context.Store);
    parameters.Set("name", "MasterVolumeSlider");
    parameters.Set("direction", "LeftToRight");
    parameters.Set("minValue", 0f);
    parameters.Set("maxValue", 1f);
    parameters.Set("wholeNumbers", false);
    parameters.Set("value", 0.75f);
 
    var invokes = GnosisNode.CreateList(Context.Store);
    var setVolume = GnosisNode.CreateObject(Context.Store);
    setVolume.Set("service", "Audio");
    setVolume.Set("function", "SetMasterVolume");
    var setVolumeArgs = GnosisNode.CreateObject(Context.Store);
    setVolumeArgs.Set("channel", "master");
    setVolumeArgs.Set("value", 0f); // Placeholder; runtime overwrites this with live slider value.
    setVolume.Set("parameters", setVolumeArgs);
    invokes.Add(setVolume);
    parameters.Set("onValueChangedInvokes", invokes);
 
    payload.Set("parameters", parameters);
    return CallService("GameUI", "CreateElement", payload);
}

Example - JSON payload shape


{
  "service": "GameUI",
  "function": "CreateElement",
  "parameters": {
    "elementId": "Slider",
    "parentId": "ui.SettingsView",
    "parameters": {
      "name": "MasterVolumeSlider",
      "direction": "LeftToRight",
      "minValue": 0.0,
      "maxValue": 1.0,
      "wholeNumbers": false,
      "value": 0.75,
      "onValueChangedInvokes": [
        {
          "service": "Audio",
          "function": "SetMasterVolume",
          "parameters": {
            "channel": "master",
            "value": 0.0
          }
        }
      ]
    }
  }
}

Example - inspect schema via DescribeUIElement

GameUI.DescribeSlider.Example.cs


private GnosisFunctionResult DescribeSliderElement()
{
    if (Context?.Store == null || Context.CallService == null)
        return GnosisFunctionResult.Fail("No context");
 
    var payload = GnosisNode.CreateObject(Context.Store);
    payload.Set("elementId", "Slider");
    return CallService("GameUI", "DescribeUIElement", payload);
}