libgdx android app crashes when loading uiskin | no logs - libgdx

Question

For some reason after adding buttons to my application it has stopped functioning on android. It works as expected on desktop, but when attempting to run on android the app builds successfully, launches, then immediately crashes before it ever loads the scene. I attempted to view the logs via aLogcat, however I see nothing in these logs indicating an issue has occurred.
I have come to the conclusion that this issue has something to do with the uiskin/buttons being added to the stage, as I can add the stage without any actors and the app will still function in android. The files outlined in the uiskin.json file are all located in /android/assets directory as they should be. Is there something I have done incorrectly? Something I have missed?
uiskin.json
{
"com.badlogic.gdx.graphics.g2d.BitmapFont":{
"default_font": {
"file": "book_antiqua.fnt"
}
},
"com.badlogic.gdx.scenes.scene2d.ui.TextButton$TextButtonStyle":{
"default": {
"down": "default-round-down",
"up": "default-round",
"font": "default_font"
}
},
"com.badlogic.gdx.scenes.scene2d.ui.Window$WindowStyle":{
"default": {
"titleFont": "default_font"
}
}
}
Main class
package com.freedom.thirty;
import com.badlogic.gdx.ApplicationListener;
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.InputMultiplexer;
import com.badlogic.gdx.assets.AssetManager;
import com.badlogic.gdx.graphics.Color;
import com.badlogic.gdx.graphics.GL20;
import com.badlogic.gdx.graphics.PerspectiveCamera;
import com.badlogic.gdx.graphics.OrthographicCamera;
import com.badlogic.gdx.graphics.VertexAttributes.Usage;
import com.badlogic.gdx.graphics.g3d.Environment;
import com.badlogic.gdx.graphics.g3d.Model;
import com.badlogic.gdx.graphics.g3d.ModelBatch;
import com.badlogic.gdx.graphics.g3d.ModelInstance;
import com.badlogic.gdx.graphics.g3d.attributes.ColorAttribute;
import com.badlogic.gdx.graphics.g3d.environment.DirectionalLight;
import com.badlogic.gdx.graphics.g3d.Material;
//import com.badlogic.gdx.graphics.g3d.utils.CameraInputController;
import com.badlogic.gdx.graphics.g3d.utils.ModelBuilder;
import com.badlogic.gdx.utils.Array;
import com.badlogic.gdx.graphics.FPSLogger;
import com.badlogic.gdx.scenes.scene2d.InputEvent;
import com.badlogic.gdx.scenes.scene2d.Stage;
import com.badlogic.gdx.scenes.scene2d.ui.Skin;
import com.badlogic.gdx.scenes.scene2d.ui.Table;
import com.badlogic.gdx.scenes.scene2d.ui.TextButton;
import com.badlogic.gdx.scenes.scene2d.utils.ClickListener;
import com.badlogic.gdx.utils.Align;
import com.badlogic.gdx.utils.viewport.FillViewport;
import com.badlogic.gdx.utils.viewport.ScreenViewport;
import com.badlogic.gdx.utils.viewport.Viewport;
import com.freedom.thirty.MyCameraInputController;
public class FreedomThirty implements ApplicationListener {
public ScreenViewport vp;
public ScreenViewport stageVp;
public OrthographicCamera cam;
public MyCameraInputController camController;
public ModelBatch modelBatch;
public AssetManager assets;
public Array<ModelInstance> allModelInstances = new Array<ModelInstance>();
public Environment environment;
public boolean loading;
// Model instances that make up the map
public ModelInstance bridge;
public ModelInstance container_001;
public ModelInstance crate_001;
public ModelInstance crate_002;
public ModelInstance crate_003;
public ModelInstance crate_004;
public ModelInstance crate_005;
public ModelInstance grass_area;
public ModelInstance gravel_area;
public ModelInstance rock_wall;
public ModelInstance water;
public ModelInstance player;
public ModelInstance skybox;
public Skin skin;
public Stage stage;
public Table table;
//public FPSLogger fpsLogger = new FPSLogger();
#Override
public void create() {
modelBatch = new ModelBatch();
assets = new AssetManager();
environment = new Environment();
environment.set(new ColorAttribute(ColorAttribute.AmbientLight, 0.8f, 0.8f, 0.8f, 1f));
//environment.add(new DirectionalLight().set(0.8f, 0.8f, 0.8f, -1f, -0.8f, -0.2f));
cam = new OrthographicCamera();
cam.position.set(-4f, 4f, 4f);
cam.lookAt(8f, 0f, -8f);
cam.near = 1f;
cam.far = 2000f;
cam.update();
// Create input controller for default scene camera. This is what allows the user to orbit around the scene
camController = new MyCameraInputController(cam);
// Set the position where the camera will look. This will need to come from json config file in the future
camController.target.set(8f, 0f, -8f);
vp = new ScreenViewport(cam);
vp.setUnitsPerPixel(0.017f);
vp.apply();
stageVp = new ScreenViewport();
stageVp.apply();
stage = new Stage(stageVp);
assets.load("uiskin.json", Skin.class);
assets.load("map_003.g3db", Model.class);
loading = true;
}
private void doneLoading(){ // Assets are now loaded into memory and can be accessed without error
// Load UI skin
skin = assets.get("uiskin.json", Skin.class);
// Define the buttons that will be in the ui table
final TextButton zoomOut = new TextButton("Zoom Out",skin,"default");
final TextButton zoomIn = new TextButton("Zoom In",skin,"default");
// Create UI table actor
table = new Table();
table.setWidth(stage.getWidth());
table.align(Align.center | Align.top);
// In the future determine what the current viewport height/width is, and set these
// to different sizes based on where the viewport falls between. Just like bootstrap's xs,sm,md,lg classes
table.setSize(250f, 250f);
table.setPosition(800f,400f);
zoomOut.setWidth(200);
zoomOut.setHeight(50);
zoomIn.setWidth(200);
zoomIn.setHeight(50);
// Event listeners for ui buttons
zoomOut.addListener(new ClickListener(){
#Override
public void clicked(InputEvent event, float x, float y){
//Gdx.app.log("Zoom Out", "Press successful");
vp.setUnitsPerPixel(vp.getUnitsPerPixel() + 0.001f);
vp.update(Gdx.graphics.getWidth(), Gdx.graphics.getHeight());
stageVp.update(Gdx.graphics.getWidth(), Gdx.graphics.getHeight());
event.stop();
}
});
zoomIn.addListener(new ClickListener(){
#Override
public void clicked(InputEvent event, float x, float y){
//Gdx.app.log("Zoom In", "Press successful");
vp.setUnitsPerPixel(vp.getUnitsPerPixel() - 0.001f);
vp.update(Gdx.graphics.getWidth(), Gdx.graphics.getHeight());
stageVp.update(Gdx.graphics.getWidth(), Gdx.graphics.getHeight());
event.stop();
}
});
// Add buttons to table
table.row().padBottom(30).padTop(30);
table.add(zoomOut);
table.add(zoomIn);
// Add table to stage
stage.addActor(table);
// Create an input multiplexer and add our stage and camController to it, set input processor to our new multiplexer
InputMultiplexer im = new InputMultiplexer(stage, camController);
Gdx.input.setInputProcessor(im);
// Load the 3d map, and character as character happens to be in the map file as of right now
// In the future each map and it's elements will be contained within it's own class, extended from
// map class
Model model = assets.get("map_003.g3db", Model.class);
bridge = new ModelInstance(model, "bridge");
allModelInstances.add(bridge);
container_001 = new ModelInstance(model, "container_001");
allModelInstances.add(container_001);
crate_001 = new ModelInstance(model, "crate_001");
allModelInstances.add(crate_001);
crate_002 = new ModelInstance(model, "crate_002");
allModelInstances.add(crate_002);
crate_003 = new ModelInstance(model, "crate_003");
allModelInstances.add(crate_003);
crate_004 = new ModelInstance(model, "crate_004");
allModelInstances.add(crate_004);
crate_005 = new ModelInstance(model, "crate_005");
allModelInstances.add(crate_005);
grass_area = new ModelInstance(model, "grass_area");
allModelInstances.add(grass_area);
gravel_area = new ModelInstance(model, "gravel_area");
allModelInstances.add(gravel_area);
rock_wall = new ModelInstance(model, "rock_wall");
allModelInstances.add(rock_wall);
water = new ModelInstance(model, "water");
allModelInstances.add(water);
player = new ModelInstance(model, "character");
allModelInstances.add(player);
player.transform.setTranslation(8f,0f,-6f); // Test character movement on the map
loading = false;
}
#Override
public void render() {
if(loading && assets.update()){
doneLoading();
}
Gdx.gl.glViewport(0, 0, Gdx.graphics.getWidth(), Gdx.graphics.getHeight());
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT | GL20.GL_DEPTH_BUFFER_BIT);
camController.update();
//Gdx.app.log("Camera Position: ", cam.position.toString());
modelBatch.begin(cam);
modelBatch.render(allModelInstances, environment);
modelBatch.end();
stage.act(Gdx.graphics.getDeltaTime());
stage.draw();
//fpsLogger.log();
}
#Override
public void dispose() {
modelBatch.dispose();
allModelInstances.clear();
assets.dispose();
}
#Override
public void resize(int width, int height) {
vp.update(width, height);
stageVp.update(width, height);
}
#Override
public void pause() {
}
#Override
public void resume() {
}
}

Answer 1

What finally corrected this issue was downloading the default uiskin files from the libgdx repository on github. Apparently I missed something when I built them from scratch? The files I used from the repo are:
uiskin.json
uiskin.atlas
default.png
uiskin.png

Answer 2

I think it takes to long to load the uiskin file. Try instead of skin = new Skin(Gdx.files.internal("uiskin.json")); something like that:
AssetManager manager = new AssetManager();
manager.load("uiskin.json", Skin.class);
manager.finishLoading();
skin = manager.get("uiskin.json", Skin.class);
Don't forget to dispose the AssetManager, when before you finish your game.