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Is there a way to drag and drop UI buttons in unity 3d?

Is there a way to drag and drop UI buttons in unity 3d?
Can I add two functions to a button?
The first when it is normally clicked it does something.
The second when it is clicked and held, it can be dragged and dropped somewhere else on the screen?
This is the code I have so far but it's not working on the button.
void Update()
{
if (isDragged)
{
transform.position = Camera.main.ScreenToWorldPoint(Input.mousePosition);
}
}
public void OnMouseOver()
{
if (Input.GetMouseButtonDown(0))
{
isDragged = true;
}
}
public void OnMouseUp()
{
isDragged = false;
}

You can use unity built-in interfaces,
Use IPointerClickHandler to do something when it is clicked and implement another three interface for handling dragging which is IBeginDragHandler, IDragHandler, IEndDragHandler
public class Example : MonoBehaviour, IPointerClickHandler, IBeginDragHandler, IDragHandler, IEndDragHandler
{
//Detect if a click occurs
public void OnPointerClick(PointerEventData pointerEventData)
{
Debug.Log(name + " Game Object Clicked!");
}
public void OnBeginDrag(PointerEventData eventData)
{
}
public void OnDrag(PointerEventData data)
{
}
public void OnEndDrag(PointerEventData eventData)
{
}
}
References : https://docs.unity3d.com/2018.1/Documentation/ScriptReference/EventSystems.IDragHandler.html

Pressing UI buttons alongside processing Input.GetMouseDown() in Update

The game I'm making is meant for mobile devices.
I have a PlayerInput class in which I check for mouse events in Update():
void Update()
{
if (Input.GetMouseButtonDown(0))
{
//hide UI elements
}
}
I have a button which I hide when I detect mouse input in PlayerInput class but I don't want to hide it if the player presses the button.
I've managed to solve this issue by adding this component to my UI elements:
public class UiPointerHandler : MonoBehaviour, IPointerEnterHandler, IPointerExitHandler
{
public void OnPointerEnter(PointerEventData eventData)
{
//disable mouse checks
}
public void OnPointerExit(PointerEventData eventData)
{
//enable mouse checks
}
}
It allows me to disable processing mouse events in PlayerInput's Update() to interact with certain UI elements.
This does its job fairly well on PC when I'm testing/prototyping the game but when I build the game for mobile it doesn't work at all and I can't press the buttons.
I'm looking for a solution that would work on mobile as well.

You can solve this fairly easily by adding the following check
void Update()
{
if (Input.GetMouseButtonDown(0) && !EventSystem.current.IsPointerOverGameObject())
{
//hide UI elements
}
}
What this does is it checks if your pointer (mouse or finger) is over an UI element. By checking if it's not, you get your desired behaviour.

See "Input.GetTouch" on 'Input' class on Unity, GetMouseButtonDown doesn't work on mobile. Unity designed 'Touch' event on mobile instead of mouse event so try it. it has to work with your code.

Thanks to user Immorality I've managed to solve my problem.
I've added the EventSystem.current.IsPointerOverGameObject() check to the Update() inside of my PlayerInput class.
void Update()
{
if(EventSystem.current.IsPointerOverGameObject()) return;
if (Input.GetMouseButtonDown(0))
{
//hide UI elements
}
}
I've tested this solution on its own and it did not help in my case, I still wasn't able to press the buttons.
I've introduced a bool in PlayerInput which controls whether the mouse input is being processed and 2 static methods allowing to change this variable.
public class PlayerInput : MonoBehaviour
{
private static bool _transmitInput;
void Update()
{
if(!_transmitInput || EventSystem.current.IsPointerOverGameObject()) return;
if (Input.GetMouseButtonDown(0))
{
//hide UI elements
}
}
public static void DisableInput()
{
if (!_transmitInput) return;
_transmitInput = false;
}
public static void EnableInput()
{
if (_transmitInput) return;
_transmitInput = true;
}
}
These are called from the UiPointerHandler:
public class UiPointerHandler : MonoBehaviour, IPointerEnterHandler, IPointerExitHandler
{
public void OnPointerEnter(PointerEventData eventData)
{
PlayerInput.DisableInput();
}
public void OnPointerExit(PointerEventData eventData)
{
PlayerInput.EnableInput();
}
}
At this point I was still having problems on mobile. When pressing the button, the OnPointerEnter() would be called but OnPointerExit() would not.
I assume it is because of how my scene is set up. The 2 buttons I'm working with are in the same position and are the same size. I just disable one and enable the other.
I solved this issue by calling PlayerInput.EnableInput() in the onClick of the buttons.

Refresh ScrollView In Unity3D

does someone know how to detect if the UI Component "ScrollView" has been pulled up?.
This is planned to be like, when you refresh the feed in youtube or facebook, with the swipe up gesture.
It should detect the gesture and then, called a method that I have : refresh();
Thanks.

ScrollRect:
You can subscribe to ScrollRect's onValueChanged event and it will be called when there are changes on the ScrollRect.
public ScrollRect scrollRect;
void OnEnable()
{
scrollRect.onValueChanged.AddListener(ScrollChanged);
}
void OnDisable()
{
scrollRect.onValueChanged.RemoveAllListeners();
}
void ScrollChanged(Vector2 pos)
{
Debug.Log("Scroll changed pos to: " + pos);
}
or you can implement the IScrollHandler interface and use the OnScroll function. The script will have to be attached to the GameObject that has the ScrollRect component for it to work.
public class ScrollDetector : MonoBehaviour, IScrollHandler
{
public void OnScroll(PointerEventData eventData)
{
}
}
Scrollbar:
If using Scrollbar, then the callback function you register with the onValueChanged event should use float instead vector2 as param.
void ScrollChanged(float val)
{
}
or implement the IMoveHandler interface and use the OnMove function
public class ScrollDetector : MonoBehaviour, IMoveHandler
{
public void OnMove(AxisEventData eventData)
{
}
}

Client doesnt get spawned gameObjects from server, and the other way around

So, I'm struggling with the whole Unet system. right now, all I want to do is to spawn object from one end to the other. but even that doesn't work. It spawns the object on each the server and the client. but doesn't sync. I've searched so many places and watched so many videos - none helped. here are the code and the inspector details
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Networking;
public class NetworkController : NetworkBehaviour
{
public GameObject[] Spawns;
GameObject Canvas;
GameObject spawn;
[SyncVar]
public NetworkInstanceId ParentId;
// Use this for initialization
void Start()
{
}
// Update is called once per frame
void Update()
{
}
[Command]
public void CmdspawnPrefab()
{
Transform trns = GameObject.Find("Canvas").transform;
trns.position = trns.position + new Vector3(100, 200, 0);
GameObject go = Instantiate(Spawns[0], trns);
NetworkServer.Spawn(go);
}
}
What am I missing?

As it seems, my whole workflow was not correct. the solution is firstly to attach a listener to the button, instead of using the onclick function on the inspector -
Button b = BoardController.Buttons[0].GetComponent<Button>();
b.onClick.AddListener(delegate () { Cmd_ButtonPressed(1); });
the second is to create gameobjects, containing a script "GameManager" who controls your board, and one "RpcManager" which contains the Rpc functions. then in the playerobject script, use the commands.
Here are the classes i have used, to update an image instead of spawning an object, the idea is basically the same - to undersand the fundamentals of Unet and passing commands.
public class PlayerObject : NetworkBehaviour {
public BoardManager BoardController;
public ClientRPCmanager ClientRPCManager;
// Use this for initialization
void Start () {
ClientRPCManager = GameObject.FindGameObjectWithTag("ClientRPCmanager").GetComponent<ClientRPCmanager>();
BoardController = ClientRPCManager.BoardController;
Button b = BoardController.Buttons[0].GetComponent<Button>();
b.onClick.AddListener(delegate () { Cmd_ButtonPressed(1); });
}
// Update is called once per frame
void Update () {
}
public void SetButton(int i)
{
BoardController.SetButton(i);
}
[Command]
public void Cmd_ButtonPressed(int i)
{
ClientRPCManager.Rpc_ButtonPressed(i);
}
boardmanager
public class BoardManager : NetworkBehaviour
{
// Use this for initialization
void Start()
{
}
// Update is called once per frame
void Update()
{
}
public GameObject[] Buttons;
public Sprite[] Sprites;
public void SetButton(int index)
{
GameObject img = GameObject.Find("X");
img.GetComponent<Image>().sprite = Sprites[0];
}
RpcManager
public class ClientRPCmanager : NetworkBehaviour {
public BoardManager BoardController;
public NetworkManager Manager;
// Use this for initialization
void Start () {
}
// Update is called once per frame
void Update () {
}
[ClientRpc]
public void Rpc_ButtonPressed(int index)
{
BoardController.SetButton(index);
}
hopefully, this will somewhat help people with understanding Unet.
I learned this by carefully looking at this project https://www.youtube.com/watch?v=8Kd2RAfgzW0

Buttons in Unity, without using UI?

Is there a way in Unity to create a simple 2D button without using the UI layer. I have a game with a lot of buttons and I don't want to make the whole app in the UI. Some more controls are welcome too: switches, sliders etc.
PS. I saw NGUI and I don't like it so far. Anything else?

Is there a way in Unity to create a simple 2D button without using the
UI layer
You can use Sprite/Sprite Render as a Button.First Create a GameObject and attach EventSystem and StandaloneInputModule to it. Attach Physics2DRaycaster to the Camera, implement IPointerClickHandler and override OnPointerClick function. Create a 2D Sprite by going to GameObject->2D Object->Sprite then attach your script to the Sprite. Here is a complete code to do that:
using UnityEngine;
using UnityEngine.EventSystems;
using System.Collections;
public class SPRITEBUTTON: MonoBehaviour, IPointerClickHandler,
IPointerDownHandler, IPointerEnterHandler,
IPointerUpHandler, IPointerExitHandler
{
void Start()
{
//Attach Physics2DRaycaster to the Camera
Camera.main.gameObject.AddComponent<Physics2DRaycaster>();
addEventSystem();
}
public void OnPointerClick(PointerEventData eventData)
{
Debug.Log("Mouse Clicked!");
}
public void OnPointerDown(PointerEventData eventData)
{
Debug.Log("Mouse Down!");
}
public void OnPointerEnter(PointerEventData eventData)
{
Debug.Log("Mouse Enter!");
}
public void OnPointerUp(PointerEventData eventData)
{
Debug.Log("Mouse Up!");
}
public void OnPointerExit(PointerEventData eventData)
{
Debug.Log("Mouse Exit!");
}
//Add Event System to the Camera
void addEventSystem()
{
GameObject eventSystem = null;
GameObject tempObj = GameObject.Find("EventSystem");
if (tempObj == null)
{
eventSystem = new GameObject("EventSystem");
eventSystem.AddComponent<EventSystem>();
eventSystem.AddComponent<StandaloneInputModule>();
}
else
{
if ((tempObj.GetComponent<EventSystem>()) == null)
{
tempObj.AddComponent<EventSystem>();
}
if ((tempObj.GetComponent<StandaloneInputModule>()) == null)
{
tempObj.AddComponent<StandaloneInputModule>();
}
}
}
}
EDIT:
If this is a 3D GameObject/Mesh, then you need to add a simple collider to it. If it is just Sprite then you must add a 2D collider to the sprite.

Another approach that is even simpler, is to just add a BoxCollider2D component, then add the following methods to the a new componenent, say UIButton, where you will to perform the button actions :
void OnMouseOver()
void OnMouseDown()
void OnMouseUp()
This avoids the use of an EventSystem, StandaloneInputModule and Physics2DRaycaster.
Example :
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using TMPro;
public class UIButton : MonoBehaviour {
public Sprite regular;
public Sprite mouseOver;
public Sprite mouseClicked;
public TextMeshPro buttonText;
// Use this for initialization
void Start () {
}
// Update is called once per frame
void Update () {
}
private void OnMouseDown()
{
}
private void OnMouseEnter()
{
}
private void OnMouseExit()
{
}
private void OnMouseUpAsButton()
{
}
}
Tested in unity 2018.1. One difference I initially noticed to this and the above approach is that the right mouse button click is not detected in this model, but is detected in the EventSystemModel.