I have this piece of code
if(personajeCreado == "0")
{
Debug.Log("hi");
UnityEngine.SceneManagement.SceneManager.LoadScene("CreandoPersonaje");
Debug.Log("bye");
}
In the debugger I only read hi, but my scene does not change, there are no errors, there is nothing to indicate a problem. please help.
Possibilities:
- You do not have the target scene included in the build
- The name of the scene is not correct (I would copy the name from the scene file itself)
- Your target scene is same as your starting scene and you did not notice the change of scene
- You have error message in your console but you have disabled the error message view and did not see the actual error
Related
I want to move my Player node (KinematicBody2D) from one scene to another. My code successfully moves Node2D node, but fails with KinematicBody2D node.
I have two Location scenes (inheriting from base Location scene) with the following structure:
FirstLocation (inherits Location)
- YSort
- Player
In the base Location scene I have two methods:
func add_player(player: Player):
get_node("YSort").add_child(player)
func remove_player() -> Player:
var player = get_node("YSort/Player")
get_node("YSort").remove_child(player)
return player
In GameWorld scene I store the possible locations inside a dictionary and the moving of the player happens inside change_location() function:
onready var _locations = {
Location.FOO: $CurrentLocation,
Location.BAR: load("res://locations/Bar.tscn").instance(),
}
onready var _current_location = $CurrentLocation
func change_location(location: int):
var player = _current_location.remove_player()
remove_child(_current_location)
_current_location = _locations[location]
add_child(_current_location)
_current_location.add_player(player)
The switching of the location works
The moving of the player also works in case the player is plain Node2D.
But when Player is KinematicBody2D then the game simply crashes, giving me no hint as to what's causing the problem.
The code works without crashing when I comment out the last line:
_current_location.add_player(player)
...but of course then the player simply doesn't get added to the other scene.
I verified that the player does get removed from the scene.
I tested with a dummy scene (which only contains KinematicBody2D as root node and a simple Sprite as a single child) instead of my actual more complex Player scene to make sure it's not related to any other code I might have in my Player scene. Node2D as root works, KinematicBody2D crashes. Must have been a fluke. Tested again and now both work, so there must be something different in my Player object.
I tried adding the Player node as a direct child of Location node (not having a YSort node in the middle) - nope, still crashes.
I tried setting the position/global_position of player before/after adding it to new scene - no difference.
I'm able to create new Player scene instance and add it to new location.
What might it be in KinematicBody2D that prevents me from moving it from scene to scene?
Found a solution, but I don't know why it works.
I was performing the location change as a response to Area2D.body_entered signal. I triggered my own signal "location_change" and then called the change_location() function in another part of the code in response to it.
Adding a tiny timeout (0.00000001 seconds) before doing the location change solved the issue. However I have no idea why, and I'm pretty sure adding timeouts is not a proper way to solve this problem.
I'm having trouble visualizing the situation. However, given that the problem happens when removing and adding a physics body, and that "body_entered" was involved, and that the solution you found was adding a time out…
Sounds like the issue was removing the physics body while Godot was still resolving physics response. And then the solution was to wait until the next frame.
You could wait until the next graphics frame with this:
yield(get_tree(), "idle_frame")
Or until the next physics frame with this:
yield(get_tree(), "physics_frame")
Which would be better than some arbitrary small timeout.
Alternatively, you could also make the signal connection deferred.
If you are connecting from the UI, there will be an "advanced" toggle in the "Connect a Signal to a Method" dialog. Enabling "advanced" toggle will reveal some extra including making the connection deferred.
If you are connecting form code, you can accomplish the same thing by passing the CONNECT_DEFERRED flag.
I am adding a main menu to my game. The thing I am doing is adding them in a scene and then changing the scene to the game scene. However, my game has errors which belong to other scenes that do not have an instance in the existing scene. I get errors such as:
Invalid get index 'HasEntered' (on base: 'null instance').
My entire project is here: https://github.com/Ripple-Studios/Godot-Wild-Jam-36-Game-Ripple-Studios
I would appreciate if someone would help me.
Thanks,
I had a look at the linked code.
What is happening is that the practice of getting nodes of the parent has come back to bite you. I'm talking code that looks like this:
get_parent().get_node(...)
You have an scene (HospitalScene.tscn) instanced in your main scene (MainMenu.tscn), which has code similar to the shown above.
The particular error you refer to comes from code that looks like this:
func _on_Area2D_body_entered(body):
var HospitalPosition = get_parent().get_node("Hospital")
if HospitalPosition.HasEntered == true:
HospitalPosition.isInHospital = false
This code is firing at the start because the Area2D is overlapping an StaticBody.
The code is trying to get a sibling "Hospital" which does not exist in the scene tree. And thus HospitalPosition is null. And trying to access HospitalPosition.HasEntered when HospitalPosition is null results in the error you mention:
Invalid get index 'HasEntered' (on base: 'null instance').
The scene is trying to reach a node outside of itself. And there is no guarantee that the scene will be instanced where such node is available. Thus, in each and every case of get_parent().get_node(...) this could happen.
In fact, when running the game, I get four error that look like this (but with different paths):
E 0:00:01.494 get_node: (Node not found: "Hospital" (relative to "/root/CanvasLayer/ParentSprite/Control").)
<C++ Error> Condition "!node" is true. Returned: nullptr
<C++ Source> scene/main/node.cpp:1325 # get_node()
<Stack Trace> HospitalScene.gd:28 # _on_Area2D_body_entered()
You could use get_node_or_null instead of get_node and check for null.
You could also export NodePath variables instead of hard-coding the paths.
Better decoupling strategies than checking if instances are valid include:
Connect to the signal from outside the scene. It is a common pattern in Godot to call down the scene tree, and signal up the scene tree. See Node communication (the right way).
Connect all the signals through an Autoload (singleton). Which is another common pattern in Godot called a Signal Bus or Event Bus. See Best practices: Godot GDScript - Event Bus.
I know, there is always a lot of questions about this error BUT I didn't succeed to fix it with the previous answers...
So, please, let me explain.
I'm working with the Hololens tech. Recently, I have updated from HoloToolKit to MRTK V2 (new SDK provided by Microsoft and the community). My app worked with HoloToolKit, Unity and 2017.4. I updated for MRTKv2 and 2019.2 (recommended).
I have some scripts that use the camera position. In my previous app, Camera was BiCamera (GameObject), child of Basic (GameObject). And my BiCamera was tagged as MainCamera. Right now, my camera was Main Camera (with a space between the 2 words), tagged MainCamera, child of MixedRealityPlayspace. This camera is provided by the MRTKv2. I can't change the settings.
So, when I'm in a Play mode I have this message in yellow :
The referenced script on this Behaviour (Game Object 'Main Camera') is missing!
And when I move my Main Camera in order to simulate a walk of the user (Hololens = augmented reality), I have this message in red :
NullReferenceException: Object reference not set to an instance of an object
TextSpeedUI.Update () (at Assets/Scripts/TextSpeedUI.cs:23)
I think the second message is linked to the first... My script TextSpeedUI needs the camera.transform to calculate walking speed (in fact not directly, he finds the public variable from another GameObject, but this GameObject requires Camera.transform).
An other option is linked with the GameObject Main Camera provided by MRTK because when I select this GameObject I have a missing script. A message says that I have to fix compile errors... But perhaps it's a consequence not the origin... I'm lost.
TextSpeedUI.cs 23
if (sd.isActiveAndEnabled && sd.Steps.Count > 4)
{
xzSpeed = (sd.Steps[sd.Steps.Count - 1].localMinPosition - sd.Steps[sd.Steps.Count - 4].localMinPosition) / ((sd.Steps[sd.Steps.Count - 1].t - sd.Steps[sd.Steps.Count - 4].t));
txt.text = (xzSpeed.magnitude * 3.6).ToString("0.##"); // speed in km/h
}
sd comes from public StepDetector sd; which is at the beginning of my script TextSpeedUI.cs
And my script StepDetector.cs calls public DataManager dm;
In my DataManager.cs script, I call at the beginning :
public Camera Cam { get; private set; }
And in void Start :
Cam = Camera.main;
Thanks a lot
I've solved by myself (just remove the component). It seems that it doesn't have consequence on my scene...
I have this weird problem.
I create my scene inside a QGraphicsView extended class like so:
scene = new QGraphicsScene(this);
this->setScene(scene);
this->setAlignment(Qt::AlignTop|Qt::AlignLeft);
showRect.setCoords(0,0,sceneWidth,sceneHeight);
However. This same class has reimplemented the resizeEvent Method according to documentation:
void ConversationView::resizeEvent(QResizeEvent *e){
//Q_UNUSED(e);
this->fitInView(showRect,Qt::KeepAspectRatioByExpanding);
qWarning() << e->size();
}
Now I add a box the scene and nothing happens. But when I start resizing the window, there comes a point where I stop and the program hangs and I keep seing the sizing message, forever and ever with very very small variations on its size:
QSize(1342, 190)
QSize(1356, 190)
QSize(1342, 190)
QSize(1356, 190)
Any ideas?
I figured out what the problem was. Instead of redefining the ConversationView's resize event (which extends from QGraphicsView), I redefined the containing Widget's resizeEvent (in this case a class based of a QDialog).
With the exact same parameters this made the problem go away.
I have 2 fxml files mainFxml.fxml and second.fxml. Main fxml has a button with fx:id="change". I want change scene when change button is clicked.
Code of mainFxml controller
public void onChangeButtonAction(event e){
Node node=(Node) event.getSource();
Stage stage=(Stage) node.getScene().getWindow();
Parent root = FXMLLoader.load(getClass().getResource("second.fxml"));/* Exception */
Scene scene = new Scene(root);
stage.setScene(scene);
stage.show();
}
but when i press button change it throws exception as no resource specified. Help me..
Stack trace
No resources specified.
file:/E:/Projects/javaFx/demo/dist/demo.jar!/demo/sucess.fxml:14
at javafx.fxml.FXMLLoader$Element.processPropertyAttribute(FXMLLoader.java:305)
at javafx.fxml.FXMLLoader$Element.processInstancePropertyAttributes(FXMLLoader.java:197)
at javafx.fxml.FXMLLoader$ValueElement.processEndElement(FXMLLoader.java:588)
at javafx.fxml.FXMLLoader.processEndElement(FXMLLoader.java:2430)
at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2136)
at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2028)
at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2742)
at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2721)
at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2707)
at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2694)
at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2683)
at demo.myFirstFxmlController.onSuccess(myFirstFxmlController.java:130)
at demo.myFirstFxmlController.OnSubmitAction(myFirstFxmlController.java:53)
It's on the classpath so it should be the resource should be precedded with a forward slash i.e.
/second.fxml
That is assuming it is not in a package. Make sure your build system is also copying it to the output directory along with your class files.
"Ah, then you need /demo/second.fxml as the resource path. Saying that, I am confused why the error message says sucess.fxml and not second.fxml. If the above suggestion doesn't work can you post the fxml? – Andy Till"
This comment from Andy Till is the answer to the question.
Thanks Andy. You solved my problem :)
Thumbs up !!!
Include the package name.
For ex:
/package_name/fxml_file_name.fxml
Most probably your file second.fxml is not located in the same folder with mainFxml.fxml's controler java file.
import java.io.IOException;
I got it to work by either surrounding the load(getClass... with a try/catch block, or by just importing java.io.IOException.
Enjoy :)