// WeatherApp.java // Andrew Davison, ad@coe.psu.ac.th, Jan 2023 /* libGDX applet demonstrating the use of HTTP to get weather data from https://www.weatherapi.com/ in JSON format, and the use of JsonBeans (https://github.com/EsotericSoftware/jsonbeans/) to use it as Java objects. Usage ----- Test as a desktop app by calling: > gradlew desktop:run Can be compiled into an GDX 'applet' using: > gradlew html:superdev -- takes around 27 secs -- access in a browser at http://localhost:8080 and > gradlew html:dist -- takes around 40 secs -- results are stored in test\html\build\dist -- then copied to a server, with index.html renamed to app.html -- my new index.html uses an iframe of size (800,600) when calling app.html, which creates a window of size (300, 200). The window size is specified in the GDX launcher code (in DesktopLauncher.java and HtmlLauncher.java). */ package com.mygdx.game; import java.io.*; import java.util.*; import com.badlogic.gdx.*; import com.badlogic.gdx.utils.*; import com.badlogic.gdx.graphics.*; import com.badlogic.gdx.scenes.scene2d.*; import com.badlogic.gdx.scenes.scene2d.ui.*; import com.badlogic.gdx.scenes.scene2d.ui.TextField.*; import com.badlogic.gdx.scenes.scene2d.utils.*; import com.badlogic.gdx.net.*; import com.badlogic.gdx.Net.*; public class WeatherApp extends ApplicationAdapter implements InputProcessor { private static final float MIN_DELAY = 1/30f; private static final String API_KEY = "xxxx"; /* This is NOT a real API key. You will need to register at https://www.weatherapi.com/ to get a key. */ private boolean isDebugging = true; private Skin skin; private Stage stage; // widgets private TextField cityTF; private TextArea weatherTA; // globals used by the input textfield private String tfInput; private boolean tfHasData = false; private boolean tfHasFocus = false; private Weather weather = null; private String errMsg = null; public void create() { Gdx.app.setLogLevel(Application.LOG_INFO); // for browser debugging Gdx.input.setCatchKey(Input.Keys.SPACE, true); // to stop scrolling on a webpage, but need to // catch spaces in code for the textfield // skin = new Skin(Gdx.files.internal("data/uiskin.json")); skin = new Skin(Gdx.files.internal("glassy/glassy-ui.json")); // https://github.com/czyzby/gdx-skins/ stage = new Stage(); stage.addActor(buildGUI()); InputMultiplexer imp = new InputMultiplexer(this, stage); Gdx.input.setInputProcessor(imp); // Gdx.input.setInputProcessor(stage); // stage.setDebugAll(true); } // end of create() private Table buildGUI() // add widgets to a table { Table t = new Table(skin); t.setFillParent(true); // first row Label lbl = new Label(" Enter city: ", skin); lbl.setAlignment(Align.center); lbl.getStyle().background = colorBackground(0.30f, 0.65f, 1.00f); // light blue t.add(lbl).pad(10); cityTF = new TextField("", skin); cityTF.setTextFieldListener(new TextFieldListener() { public void keyTyped(TextField textField, char key) // keep updating tfInput until ENTER is typed { if (!tfHasData) { if ((key == '\r') || (key == '\n') || (key == Input.Keys.ENTER)) { lookupWeather(tfInput.trim()); } else tfInput = textField.getText(); } } }); cityTF.addListener(new FocusListener() { public void keyboardFocusChanged(FocusListener.FocusEvent event, Actor actor, boolean isFocused) { tfHasFocus = isFocused; } }); t.add(cityTF).fillX().align(Align.left).padBottom(5); t.row(); // second row weatherTA = new TextArea("", skin); weatherTA.setPrefRows(6); weatherTA.setDisabled(true); // not editable t.add(weatherTA).colspan(2).fillX(); t.row(); return t; } // end of buildGUI() private void lookupWeather(String cityStr) /* send a GET request to https://www.weatherapi.com/, and wait for the response that may be JSON data */ { dprint("Looking up: \"" + cityStr + "\""); // build GET parameters HashMap paramsMap = new HashMap(); paramsMap.put("key", API_KEY); paramsMap.put("q", cityStr); paramsMap.put("aqi", "no"); HttpRequestBuilder requestBuilder = new HttpRequestBuilder(); HttpRequest req = requestBuilder.newRequest(). method(HttpMethods.GET). url("http://api.weatherapi.com/v1/current.json"). // current weather content( HttpParametersUtils.convertHttpParameters(paramsMap)). timeout(5000). // ms build(); Gdx.net.sendHttpRequest(req, new Net.HttpResponseListener() { public void handleHttpResponse(Net.HttpResponse resp) { int status = resp.getStatus().getStatusCode(); if (status == 200) // data was retrieved buildWeather(resp); else buildError(status, resp); } public void failed(Throwable t) { errMsg = "Website access failed"; } public void cancelled() { dprint("Cancelled"); } }); // end of HttpResponseListener } // end of lookupWeather() private void buildWeather(Net.HttpResponse resp) // extract a Weather object from the JSON response { String jsonStr = resp.getResultAsString(); if (jsonStr == null) errMsg = "Website data is empty"; else { Json json = new Json(); dprint("\nResult: \n" + json.prettyPrint(jsonStr) + "\n"); Weather w = json.fromJson(Weather.class, jsonStr); // GWT requires class config for serialization // in \weather\core\src\WeatherApp.gwt.xml // https://libgdx.com/wiki/utils/reflection if (w != null) { weather = w; tfHasData = true; } else errMsg = "Could not parse JSON data"; } } // end of buildWeather() private void buildError(int status, Net.HttpResponse resp) // extract a WeatherError object from the JSON response { errMsg = "Website error: " + status; String jsonStr = resp.getResultAsString(); if (jsonStr != null) { Json json = new Json(); dprint("Error: \n" + json.prettyPrint(jsonStr) + "\n"); WeatherError wErr = json.fromJson(WeatherError.class, jsonStr); // GWT requires class config for serialization // in \weather\core\src\WeatherApp.gwt.xml // https://libgdx.com/wiki/utils/reflection if (wErr != null) { Error err = wErr.getError(); errMsg += "; " + err.getMessage(); } } } // end of buildError() public void render() { ScreenUtils.clear(Color.WHITE); showWeatherInfo(); stage.act( Math.min(Gdx.graphics.getDeltaTime(), MIN_DELAY)); stage.draw(); } // end of render() private void showWeatherInfo() // update text area, either with weather info or an error message { if (tfHasData) { // there is weather data dprint("Building report"); Location loc = weather.getLocation(); Current current = weather.getCurrent(); Condition cond = current.getCondition(); String report = loc.getName() + ", " + loc.getRegion() + ", " + loc.getCountry() + "\n" + current.getTemp_c() + "c, " + cond.getText() + "\n" + loc.getLocaltime(); dprint(report); weatherTA.setText(report); tfHasData = false; // data has been reported } // instead of weather data there might // be an error message to report if (errMsg != null) { weatherTA.setText(errMsg); errMsg = null; // error has been reported } } // end of showWeatherInfo() private TextureRegionDrawable colorBackground(float r, float g, float b) // a pixel used for coloring backgrounds { Pixmap pixmap = new Pixmap(1,1, Pixmap.Format.RGBA8888); pixmap.setColor(r, g, b, 1f); // (red,green,blue) pixmap.fill(); TextureRegionDrawable bg = new TextureRegionDrawable( new Texture(pixmap)); pixmap.dispose(); return bg; } // end of colorBackground() public void resize(int width, int height) // no resizing is possible, so this method isn't needed { stage.getViewport().update(width, height, true); } public void dispose() { stage.dispose(); skin.dispose(); } private void dprint(String s) // print debugging info to the desktop or to the browser console { if (isDebugging) { if (isWebGL()) Gdx.app.log("WeatherApp", s); // appears in browser web console // which is displayed in Firefox with ctrl-shift-i else System.out.println(s); } } // end of dprint() private boolean isWebGL() { return (Gdx.app.getType() == Application.ApplicationType.WebGL); } // InputProcessor methods ------------------------ public boolean touchUp(int x, int y, int pointer, int button) { return false; } public boolean touchDragged(int x, int y, int pointer) { return false; } public boolean touchDown(int x, int y, int pointer, int button) { return false; } public boolean scrolled(float amountX, float amountY) { return false; } public boolean mouseMoved(int x, int y) { return false; } public boolean keyUp(int code) { return false; } public boolean keyTyped(char ch) { return false; } public boolean keyDown(int code) { if ((code == Input.Keys.SPACE) && isWebGL() && tfHasFocus) { dprint("space pressed in textfield"); int pos = cityTF.getCursorPosition(); // String lets = Input.Keys.toString(code); // "SPACE" cityTF.setText( insertStr(cityTF.getText(), " ", pos)); cityTF.setCursorPosition(pos+1); tfInput = cityTF.getText(); } return false; } private String insertStr(String s, String lets, int pos) { return (s.substring(0, pos) + lets + s.substring(pos)); } } // end of WeatherApp class