Creating Buttons

[kwelts]

I have the following code:

using UnityEngine;
using System.Collections;

public class ObjectArray : MonoBehaviour {
   
   object uiObject;
   
   public void main() {
   string[] array1 = new string[8] {"Do", "Re", "Mi", "Fa", "So", "La", "Ti", "Doe"};   
      int dx = 40;
      int dy = 40;
      uiObject = GameObject.Find("Button");
   }
      
   public void createButtons() {
         
      for (int i = 0; i < 8; i++) {
            NGUITools.AddChild(uiObject);
            // uiObject.titleLabel.Font = [UIFont systemFontOfSize:size];
            uiObject.TitleLabel.Text = array1;
            uiObject.Transform.Translate(Vector3.right * dx, Vector3.down * dy);
         } // end for()
   }
}

I am trying to make buttons for each index of an array. my code no longer has red underlines but the compiler says that there are invalid arguments for "NGUITools.AddChild(uiObject)". How do I fix this?

[PhilipC]

Your trying to pass a object of type 'object' the function is expecting 'GameObject' the compiler will not automatically cast this for you.

[Ferazel]

Phillip got here first, but the problem is that object != GameObject so the compiler is warning you about that.

Also if you want to create duplicate instances of a button that you setup in the editor you are still going to need to perform a GameObject.Instantiate(uiObject); before you do a NGUITools.AddChild().

1. ...
2. GameObject newButton = GameObject.Instantiate(uiObject);
3. NGUITools.AddChild(newButton);
4. UILabel newButtonLabel = newButton.GetComponentInChildren<UILabel>();
5. newButtonComp.text = array1[i];
6. ...
7.  

[kwelts]

Forgive me as i'm new to C#. I have put in your changes and changed the code a tiny bit more but it still gives an error "Cannot implicitly convert type object to GameObject. an explicit conversion exists (are you missing a cast?)". I cant see the error in what I did. thanks in advance:

using UnityEngine;
using System.Collections;

public class ObjectArray : MonoBehaviour {
   
   UIButton uiObject;
   
   public void main() {
   string[] array1 = new string[8] {"Do", "Re", "Mi", "Fa", "So", "La", "Ti", "Doe"};   
      int dx = 40;
      int dy = 40;
      uiObject = GameObject.Find("Button").GetComponent<UIButton>();
   }
      
   public void createButtons() {
         
      for (int i = 0; i < 8; i++) {
            GameObject newButton = GameObject.Instantiate(uiObject);
            NGUITools.AddChild(newButton);
            UILabel newButtonLabel = newButton.GetComponentInChildren<UILabel>();
            newButtonComp.text = array1;
            uiObject.Transform.Translate(Vector3.right * dx, Vector3.down * dy);
         } // end for()
   }
}

[ArenMook]

GameObject newButton = GameObject.Instantiate(uiObject) as GameObject;

However, I suggest doing this instead:

1. GameObject newButton = NGUITools.AddChild(gameObject, uiObject);

[kwelts]

"(gameObject, uiObject);"

this part doesnt work. it expects the uiObject but gets the gameObject instead.

Nevermind I got this part working. will post if another error arises.

[ArenMook]

It needs to be a prefab. Change "UIButton uiObject;" to "GameObject uiObject;"

I suggest you learn how to work with prefabs in Unity.

[kwelts]

I'm now getting a nullReferenceException:

using UnityEngine;
using System.Collections;

public class ObjectArray : MonoBehaviour {
   
   GameObject uiObject;
   string[] array1;
   Vector3 temp = new Vector3(0,50.0f,0);
   
   void Start() {
   array1 = new string[8] {"Do", "Re", "Mi", "Fa", "So", "La", "Ti", "Doe"};
      /*for(int i=0; i < array1.Length; i++) {
      Debug.Log(array1);
      } */
      createButtons();
      uiObject = GameObject.Find("Button");
   }
      
   public void createButtons() {
      //Debug.Log("Got here!");
      for (int i = 0; i < array1.Length; i++) {
         GameObject newButton = GameObject.Instantiate(uiObject) as GameObject;
            NGUITools.AddChild(newButton);
         UILabel newButtonLabel = newButton.GetComponentInChildren<UILabel>();
         newButtonLabel.text = array1;
         newButton.transform.position += temp;
         } // end for()
   
   } // end createButtons()
   
} // end class()

I've created a prefab of a button and I need to instantiate it in the scene but think the error might be because I do not know how to find the prefab since GameObject is only finding items in the hierarchy and not the project view itself.

[PhilipC]

As suggested by Mike earlier.

1. GameObject newButton = NGUITools.AddChild(gameObject, uiObject);

Should be used instead of

1. GameObject newButton = GameObject.Instantiate(uiObject) as GameObject;
2. NGUITools.AddChild(newButton);
3.  

You should create the prefab but also make GameObject uiObject public so you can assign the prefab to the variable from the inspector.

The reason you are getting a Null Referenceexception because you currently have

1. createButtons();
2. uiObject = GameObject.Find("Button");
3.  

but you are trying to use uiObject inside of createButtons() (aka you have not assigned uiObject yet).

[kwelts]

thank you very much for the response. Ive made the changes but now have noticed that when i hit play, it clears my uiObject which is why im getting a nullReferenceException. pics included of before pressing play, and while scene is running:

[PhilipC]

Do you still have the uiObject = GameObject.Find("Button"); in your code? if so remove it as its not longer needed

[kwelts]

thank you very much! I'll look into why it works that way.

[kwelts]

Hello again. So i've gotten the create buttons to work properly when its an isolated class, but now I am trying to call it from a static method:

1. //Method
2.  
3. public static void AddCheckInButtons(){
4.  
5. for(int i = 0; i < checkInArray.Count; i++){
6.  
7. Debug.Log("--->Start For Loop");
8.  
9. GameObject g = GameObject.Find("CheckIn_Panel");
10.  
11. Debug.Log("--->GameObject");
12.  
13. CheckInButton checkButton = g.AddComponent<CheckInButton>();
14.  
15. Debug.Log("--->CheckIn Button");
16.  
17. checkButton.SetPosition(i);
18.  
19. checkButton.SetCheckInObject(checkInArray[i]);
20.  
21. checkButton.CreateButton();
22.  
23. }
24.  
25. }
26.  
27.  
28.  
29. //Class
30.  
31. using UnityEngine;
32.  
33. using System.Collections;
34.  
35.  
36.  
37. public class CheckInButton : MonoBehaviour {
38.  
39. //Properties
40.  
41. string ButtonName {get;set;}
42.  
43. int Position{get;set;}
44.  
45. CheckIn CheckInObject {get;set;}
46.  
47.  
48. //Variables
49.  
50. public GameObject uiObject;
51.  
52. float buttonVariance = -45.0f;
53.  
54.  
55. void Start(){}
56.  
57.  
58. //Creates a button to use with Check In UI
59.  
60. public void CreateButton(){
61.  
62. Debug.Log("--->CreateButton");
63.  
64. GameObject newButton = NGUITools.AddChild(gameObject, uiObject);
65.  
66. Debug.Log("--->GameObject newButton");
67.  
68. UILabel newButtonLabel = newButton.GetComponentInChildren<UILabel>();
69.  
70. Debug.Log("--->UILabel newButtonLabel");
71.  
72. newButtonLabel.text = ButtonName;
73.  
74. newButton.transform.localPosition = new Vector3(0.0f, ((buttonVariance*Position)+140.0f), 0.0f);
75.  
76. }
77.  
78.  
79. //Setter for Position
80.  
81. public void SetPosition(int position){
82.  
83. Position = position;
84.  
85. }
86.  
87.  
88. //Setter for CheckInObject and ButtonName
89.  
90. public void SetCheckInObject(CheckIn checkIn){
91.  
92. CheckInObject = checkIn;
93.  
94. ButtonName = checkIn.name;
95.  
96.  
97. }
98.  
99. }

from running traces it seems to not be working at:
"GameObject newButton = NGUITools.AddChild(gameObject, uiObject);"
it is giving me a null exception.

Is there a way to determine which part of the line is null? As far as I can tell all the material is in the proper places in prefabs/hierarchy.

[PhilipC]

Not being able to view you scene i can only take a guess at whats wrong by the code.

Your doing a "CheckInButton checkButton = g.AddComponent<CheckInButton>();" which suggests to me that your are adding the script dynamically to the "CheckIn_Panel". If so "public GameObject uiObject;" will not be set as you don't set it anywhere. This would cause the null reference exception.

Also as a side note why are you adding the CheckInButton component to the same GameObject (which you are also finding each iteration) multiple times (talk about a performance hit!)?