Unity script error

I'm currently working on a project, But I've ran into an error. I have no clue how to fix it, these are my errors:

Assets/Standard Assets/CrossPlatformInput/Scripts/AxisTouchButton.cs(3,19): error CS0234: The type or namespace name `EventSystems' does not exist in the namespace `UnityEngine'. Are you missing an assembly reference?

Assets/Standard Assets/CrossPlatformInput/Scripts/AxisTouchButton.cs(7,55): error CS0246: The type or namespace name `IPointerDownHandler' could not be found. Are you missing a using directive or an assembly reference?

Assets/Standard Assets/CrossPlatformInput/Scripts/AxisTouchButton.cs(7,76): error CS0246: The type or namespace name `IPointerUpHandler' could not be found. Are you missing a using directive or an assembly reference?

Assets/Standard Assets/CrossPlatformInput/Scripts/Joystick.cs(3,19): error CS0234: The type or namespace name `EventSystems' does not exist in the namespace `UnityEngine'. Are you missing an assembly reference?


Assets/Standard Assets/CrossPlatformInput/Scripts/Joystick.cs(7,48): error CS0246: The type or namespace name `IPointerDownHandler' could not be found. Are you missing a using directive or an assembly reference?


Assets/Standard Assets/CrossPlatformInput/Scripts/Joystick.cs(7,69): error CS0246: The type or namespace name `IPointerUpHandler' could not be found. Are you missing a using directive or an assembly reference?


ssets/Standard Assets/CrossPlatformInput/Scripts/Joystick.cs(7,88): error CS0246: The type or namespace name `IDragHandler' could not be found. Are you missing a using directive or an assembly reference?

Assets/Standard Assets/CrossPlatformInput/Scripts/TouchPad.cs(3,19): error CS0234: The type or namespace name `EventSystems' does not exist in the namespace `UnityEngine'. Are you missing an assembly reference?

Assets/Standard Assets/CrossPlatformInput/Scripts/TouchPad.cs(4,19): error CS0234: The type or namespace name `UI' does not exist in the namespace `UnityEngine'. Are you missing an assembly reference?

Assets/Standard Assets/CrossPlatformInput/Scripts/TouchPad.cs(9,48): error CS0246: The type or namespace name `IPointerDownHandler' could not be found. Are you missing a using directive or an assembly reference?


Assets/Standard Assets/CrossPlatformInput/Scripts/TouchPad.cs(9,69): error CS0246: The type or namespace name `IPointerUpHandler' could not be found. Are you missing a using directive or an assembly reference?


Assets/Standard Assets/Utility/EventSystemChecker.cs(4,19): error CS0234: The type or namespace name `EventSystems' does not exist in the namespace `UnityEngine'. Are you missing an assembly reference?

Assets/Standard Assets/Utility/FPSCounter.cs(3,19): error CS0234: The type or namespace name `UI' does not exist in the namespace `UnityEngine'. Are you missing an assembly reference?

My Script is:

Code (CSharp):

1. using System;
2. using UnityEngine;
3. using UnityEngine.EventSystems;
4.  
5. namespace UnityStandardAssets.CrossPlatformInput
6. {
7.     public class AxisTouchButton : MonoBehaviour, IPointerDownHandler, IPointerUpHandler
8.     {
9.         // designed to work in a pair with another axis touch button
10.         // (typically with one having -1 and one having 1 axisValues)
11.         public string axisName = "Horizontal"; // The name of the axis
12.         public float axisValue = 1; // The axis that the value has
13.         public float responseSpeed = 3; // The speed at which the axis touch button responds
14.         public float returnToCentreSpeed = 3; // The speed at which the button will return to its centre
15.  
16.         AxisTouchButton m_PairedWith; // Which button this one is paired with
17.         CrossPlatformInputManager.VirtualAxis m_Axis; // A reference to the virtual axis as it is in the cross platform input
18.  
19.         void OnEnable()
20.         {
21.             if (!CrossPlatformInputManager.AxisExists(axisName))
22.             {
23.                 // if the axis doesnt exist create a new one in cross platform input
24.                 m_Axis = new CrossPlatformInputManager.VirtualAxis(axisName);
25.                 CrossPlatformInputManager.RegisterVirtualAxis(m_Axis);
26.             }
27.             else
28.             {
29.                 m_Axis = CrossPlatformInputManager.VirtualAxisReference(axisName);
30.             }
31.             FindPairedButton();
32.         }
33.  
34.         void FindPairedButton()
35.         {
36.             // find the other button witch which this button should be paired
37.             // (it should have the same axisName)
38.             var otherAxisButtons = FindObjectsOfType(typeof(AxisTouchButton)) as AxisTouchButton[];
39.  
40.             if (otherAxisButtons != null)
41.             {
42.                 for (int i = 0; i < otherAxisButtons.Length; i++)
43.                 {
44.                     if (otherAxisButtons[i].axisName == axisName && otherAxisButtons[i] != this)
45.                     {
46.                         m_PairedWith = otherAxisButtons[i];
47.                     }
48.                 }
49.             }
50.         }
51.  
52.         void OnDisable()
53.         {
54.             // The object is disabled so remove it from the cross platform input system
55.             m_Axis.Remove();
56.         }
57.  
58.  
59.         public void OnPointerDown(PointerEventDat data)
60.         {
61.             if (m_PairedWith == null)
62.             {
63.                 FindPairedButton();
64.             }
65.             // update the axis and record that the button has been pressed this frame
66.             m_Axis.Update(Mathf.MoveTowards(m_Axis.GetValue, axisValue, responseSpeed * Time.deltaTime));
67.         }
68.  
69.  
70.         public void OnPointerUp(PointerEventData data)
71.         {
72.             m_Axis.Update(Mathf.MoveTowards(m_Axis.GetValue, 0, responseSpeed * Time.deltaTime));
73.         }
74.     }
75. }

Can someone help me fix the errors, and explain what they are?

 

I would guess that your project doesn't reference UnityEngine.UI.dll.

 

This. What version of Unity are you using?

 

I am having the same issue and i am using Unity5.4.1
how did you fix it ??

 

Include

Code (csharp):

1. using UnityEngine.UI;

in your script, if I understand correctly

 

Closing unity and opening it again fixed for me hahaha. Thanks for the reply though, i'll try it next time i get them. It was only coming when i was building the project