EditorGUI.showMixedValue

Description

Makes the following controls give the appearance of editing multiple different values.

This is sometimes useful when creating custom editors and you want to represent a value in a non-standard way in the GUI while also supporting multi-object editing.

// This example shows a custom inspector for an object "MyVessel".
// MyVessel has a boolean variable isFast but we want to show it
// as a dropdown instead of as a toggle.

enum SpeedOption { Slow, Fast }

@CustomEditor (MyVessel)
@CanEditMultipleObjects
class MyVesselEditor extends Editor {
    var isFastProp : SerializedProperty;
    
    function OnEnable () {
        isFastProp = serializedObject.FindProperty ("isFast");
    }
    
    function OnInspectorGUI () {
        serializedObject.Update ();
        
        // Show the isFast boolean the standard way - as a toggle:
        EditorGUILayout.PropertyField (isFastProp);
        
        // Show the isFast boolean as a dropdown using the SpeedOption enum defined above:
        
        // Check if the value was changed inside this block
        EditorGUI.BeginChangeCheck ();
        
        // If the isFast property represent multiple different values, the dropdown should show that:
        EditorGUI.showMixedValue = isFastProp.hasMultipleDifferentValues;
        
        // Convert the isFast boolean to an enum value
        var speedOptionEnumValue : SpeedOption;
        if (isFastProp.boolValue == true)
            speedOptionEnumValue = SpeedOption.Fast;
        else
            speedOptionEnumValue = SpeedOption.Slow;
        
        // Present the enum value in a dropdown:
        speedOptionEnumValue = EditorGUILayout.EnumPopup ("Speed", speedOptionEnumValue);
        
        // Set showMixedValue to false so it doesn't affect the following controls, if any:
        EditorGUI.showMixedValue = false;
        
        // If the value was changed inside this block, apply the new value to all the objects:
        if (EditorGUI.EndChangeCheck ())
            isFastProp.boolValue = (speedOptionEnumValue == SpeedOption.Fast ? true : false);
        
        serializedObject.ApplyModifiedProperties ();
    }
}

// This is the MyVessel script used above

var isFast : boolean = false;

function Update () {
    // Update logic here...
}