Add a loading screen (#629)

* Add a loading screen
* Preloader in its own jar
* ProgressBar displays progress

Author: AustinShalit

build.gradle

@@ -300,6 +300,19 @@ project(":core") {
     }
 }
 
+project (":ui:preloader") {
+    apply plugin: 'java'
+    apply plugin: 'idea'
+    apply plugin: 'jacoco'
+    apply plugin: 'application'
+
+    task run(overwrite: true, type: JavaExec) {
+        classpath = sourceSets.main.runtimeClasspath
+        main = 'edu.wpi.grip.preloader.GripPreloader'
+        args 'windowed'
+    }
+}
+
 project(":ui") {
     apply plugin: 'java'
     apply plugin: 'idea'
@@ -313,6 +326,7 @@ project(":ui") {
 
     dependencies {
         compile project(path: ':core', configuration: 'shadow')
+        compile project(path: ':ui:preloader')
         ideProvider project(path: ':core', configuration: 'compile')
         compile group: 'org.controlsfx', name: 'controlsfx', version: '8.40.11'
         compile group: 'com.hierynomus', name: 'sshj', version: '0.16.0'
@@ -324,6 +338,7 @@ project(":ui") {
     }
 
     evaluationDependsOn(':core')
+    evaluationDependsOnChildren()
     compileTestJava.dependsOn tasks.getByPath(':core:testClasses')
 
     idea.module {
@@ -362,6 +377,8 @@ project(":ui") {
         // and as such, would be useless.
         // See: https://plumbr.eu/blog/java/on-a-quest-for-missing-stacktraces
         jvmArgs = ["-XX:-OmitStackTraceInFastThrow"]
+
+        systemProperties = ['javafx.preloader':'edu.wpi.grip.preloader.GripPreloader']
     }
     mainClassName = javafx.mainClass
 

settings.gradle

@@ -1,3 +1,2 @@
-include 'core', 'ui'
+include 'core', 'ui', 'ui:preloader'
 rootProject.name = 'GRIP'
-

ui/preloader/src/main/java/edu/wpi/grip/preloader/GripPreloader.java

@@ -0,0 +1,53 @@
+package edu.wpi.grip.preloader;
+
+import java.io.IOException;
+import javafx.application.Preloader;
+import javafx.fxml.FXMLLoader;
+import javafx.scene.Parent;
+import javafx.scene.Scene;
+import javafx.scene.control.ProgressBar;
+import javafx.stage.Stage;
+import javafx.stage.StageStyle;
+
+public final class GripPreloader extends Preloader {
+
+  private ProgressBar progressBar;
+  private Stage preloaderStage;
+
+  public static void main(String[] args) {
+    launch(args);
+  }
+
+  @Override
+  public void start(Stage preloaderStage) throws IOException {
+    Parent root = FXMLLoader.load(GripPreloader.class.getResource("Preloader.fxml"));
+    Scene scene = new Scene(root);
+
+    progressBar = (ProgressBar) root.getChildrenUnmodifiable().filtered(
+        p -> p instanceof ProgressBar).get(0);
+
+    System.setProperty("prism.lcdtext", "false");
+
+    if (getParameters().getRaw().contains("windowed")) {
+      preloaderStage.initStyle(StageStyle.UTILITY);
+    } else {
+      preloaderStage.initStyle(StageStyle.TRANSPARENT);
+    }
+    preloaderStage.setScene(scene);
+    preloaderStage.setAlwaysOnTop(true);
+    preloaderStage.setResizable(false);
+    preloaderStage.show();
+
+    this.preloaderStage = preloaderStage;
+  }
+
+  @Override
+  public void handleApplicationNotification(PreloaderNotification pn) {
+    if (pn instanceof ProgressNotification) {
+      progressBar.setProgress(((ProgressNotification) pn).getProgress());
+    } else if (pn instanceof StateChangeNotification
+        && ((StateChangeNotification) pn).getType() == StateChangeNotification.Type.BEFORE_START) {
+      preloaderStage.hide();
+    }
+  }
+}

ui/preloader/src/main/resources/edu/wpi/grip/preloader/Preloader.css

@@ -0,0 +1,8 @@
+.root {
+    -fx-padding: 25;
+}
+
+.progress-bar {
+    -fx-padding: 25 0 0 0;
+    -fx-accent: #6C8058;
+}

ui/preloader/src/main/resources/edu/wpi/grip/preloader/Preloader.fxml

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<?import java.net.URL?>
+<?import javafx.scene.control.ProgressBar?>
+<?import javafx.scene.image.Image?>
+<?import javafx.scene.image.ImageView?>
+<?import javafx.scene.layout.VBox?>
+<?import javafx.stage.Screen?>
+<VBox id="root" xmlns="http://javafx.com/javafx/8.0.65" xmlns:fx="http://javafx.com/fxml/1">
+   <children>
+      <ImageView fitWidth="${screen.visualBounds.width / 4}" pickOnBounds="true" preserveRatio="true">
+         <image>
+            <Image url="@grip.png" />
+         </image>
+         <fx:define>
+            <Screen fx:factory="getPrimary" fx:id="screen"/>
+         </fx:define>
+      </ImageView>
+      <ProgressBar id="progress-bar" maxWidth="1.7976931348623157E308" />
+   </children>
+   <stylesheets>
+      <URL value="@Preloader.css" />
+   </stylesheets>
+</VBox>

ui/preloader/src/main/resources/edu/wpi/grip/preloader/grip.png

@@ -30,6 +30,7 @@
 import java.util.logging.Logger;
 import javafx.application.Application;
 import javafx.application.Platform;
+import javafx.application.Preloader;
 import javafx.fxml.FXMLLoader;
 import javafx.scene.Parent;
 import javafx.scene.Scene;
@@ -58,14 +59,14 @@ public class Main extends Application {
   @Inject private GripServer server;
   @Inject private HttpPipelineSwitcher pipelineSwitcher;
   private Parent root;
+  private boolean headless;
 
   public static void main(String[] args) {
     launch(args);
   }
 
   @Override
-  @SuppressWarnings("PMD.SignatureDeclareThrowsException")
-  public void start(Stage stage) throws Exception {
+  public void init() throws IOException {
     List<String> parameters = new ArrayList<>(getParameters().getRaw());
 
     if (parameters.contains("--headless")) {
@@ -76,35 +77,28 @@ public void start(Stage stage) throws Exception {
       injector.injectMembers(this);
 
       parameters.remove("--headless");
+      headless = true;
     } else {
       // Otherwise, run with both the core and UI modules, and show the JavaFX stage
       injector = Guice.createInjector(Modules.override(new GripCoreModule(), new GripFileModule(),
           new GripSourcesHardwareModule()).with(new GripNetworkModule(), new GripUiModule()));
-
       injector.injectMembers(this);
+      notifyPreloader(new Preloader.ProgressNotification(0.15));
 
       System.setProperty("prism.lcdtext", "false");
       Font.loadFont(this.getClass().getResource("roboto/Roboto-Regular.ttf").openStream(), -1);
       Font.loadFont(this.getClass().getResource("roboto/Roboto-Bold.ttf").openStream(), -1);
       Font.loadFont(this.getClass().getResource("roboto/Roboto-Italic.ttf").openStream(), -1);
       Font.loadFont(this.getClass().getResource("roboto/Roboto-BoldItalic.ttf").openStream(), -1);
-
-      root = FXMLLoader.load(Main.class.getResource("MainWindow.fxml"), null, null,
-          injector::getInstance);
-      root.setStyle("-fx-font-size: " + DPIUtility.FONT_SIZE + "px");
-
-      // If this isn't here this can cause a deadlock on windows. See issue #297
-      stage.setOnCloseRequest(event -> SafeShutdown.exit(0, Platform::exit));
-      stage.setTitle("GRIP Computer Vision Engine");
-      stage.getIcons().add(new Image("/edu/wpi/grip/ui/icons/grip.png"));
-      stage.setScene(new Scene(root));
-      stage.show();
+      notifyPreloader(new Preloader.ProgressNotification(0.3));
     }
 
     operations.addOperations();
     cvOperations.addOperations();
+    notifyPreloader(new Preloader.ProgressNotification(0.45));
     server.addHandler(pipelineSwitcher);
     server.start();
+    notifyPreloader(new Preloader.ProgressNotification(0.6));
 
     // If there was a file specified on the command line, open it immediately
     if (!parameters.isEmpty()) {
@@ -117,6 +111,27 @@ public void start(Stage stage) throws Exception {
     }
 
     pipelineRunner.startAsync();
+    notifyPreloader(new Preloader.ProgressNotification(0.75));
+  }
+
+  @Override
+  public void start(Stage stage) throws IOException {
+    if (!headless) {
+      root = FXMLLoader.load(Main.class.getResource("MainWindow.fxml"), null, null,
+          injector::getInstance);
+      root.setStyle("-fx-font-size: " + DPIUtility.FONT_SIZE + "px");
+      notifyPreloader(new Preloader.ProgressNotification(0.9));
+
+      // If this isn't here this can cause a deadlock on windows. See issue #297
+      stage.setOnCloseRequest(event -> SafeShutdown.exit(0, Platform::exit));
+      stage.setTitle("GRIP Computer Vision Engine");
+      stage.getIcons().add(new Image("/edu/wpi/grip/ui/icons/grip.png"));
+      stage.setScene(new Scene(root));
+      notifyPreloader(new Preloader.ProgressNotification(1.0));
+      notifyPreloader(new Preloader.StateChangeNotification(
+          Preloader.StateChangeNotification.Type.BEFORE_START));
+      stage.show();
+    }
   }
 
   public void stop() {