Javafx - relógio digital

Apresento aqui um excelente relógio digital
criado com os poderosos recursos da biblioteca javaFx.
Os acertos das horas, minutos e segundos são feitos
manualmente através de textfield bem organizados,
com limites de caracteres de colunas e de números
superiores aos que condizem com os horários normais.
O clock das contagens por segundos, é o que faz
todo o processo se tornar real, e as atualizações da tela
são feitas pelo método Apaga(); que contem um método
interno que limpa todos os pixels de um determinado
espaço na tela.

Veja abaixo um vídeo do programa em execução:

Veja abaixo imagens do programa em execução:

                              

Veja abaixo o código do programa:

import javafx.application.Application;

import javafx.event.ActionEvent;

import javafx.scene.Scene;

import javafx.scene.canvas.Canvas;

import javafx.scene.canvas.GraphicsContext;

import javafx.stage.Stage;

import javafx.animation.KeyFrame;

import javafx.animation.Timeline;

import javafx.event.EventHandler;

import javafx.scene.paint.Color;

import javafx.util.Duration;

import javafx.scene.layout.BorderPane;

import javafx.scene.layout.Pane;

import javafx.scene.text.Font;

import javafx.scene.text.FontWeight;

import javafx.scene.text.Text;

import javafx.animation.*;

import javafx.concurrent.Task;

import javafx.scene.control.Menu;

import javafx.scene.control.MenuBar;

import javafx.scene.control.MenuItem;

import javafx.scene.control.TextField;

import javafx.scene.control.Button;

import javafx.scene.Node;

import javafx.geometry.Insets;

import javafx.scene.layout.HBox;

import javafx.scene.input.KeyCode;

import javafx.scene.input.KeyEvent;

import java.util.function.UnaryOperator;

import javafx.scene.control.TextFormatter;

import javafx.scene.control.TextFormatter.Change;

////////////////////////////////////////////////////////////////////////////////

public class PROJETO extends Application {

     private static Timeline videoTick_1;

     static int a = 0, b = 0, c = 0, d = 0, e = 0,

              f = 0, g = 0, h = 0, k = 0, w = 0;       

     static int hora, min, seg;

     static String str_0 = "";

     static String str_1 = "";

     static String str_2 = "";

     static Canvas canvas = new Canvas ( 490, 310 );

     static GraphicsContext ctx = canvas.getGraphicsContext2D ( );

     static BorderPane borderPane = new BorderPane ( );

     static Text text1 = new Text ( );

     static Button btn_2 = new Button ( "cls" );

     static TextField textField_1 = new TextField ( );

     static HBox hbox_1 = new HBox ( textField_1 );

     static TextField textField_2 = new TextField ( );

     static HBox hbox_2 = new HBox ( textField_2 );

     static TextField textField_3 = new TextField ( );

     static HBox hbox_3 = new HBox ( textField_3 );

     static Pane root = new Pane ( );

     static Scene scene = new Scene ( root, 490, 310, Color.WHITE );

     static MenuBar menuBar = new MenuBar ( );

     // //////////////////////////////////////////////////////////////////////////

     public static int Apaga ( int tam_lin_ini, int tam_lin_fim,

              int tam_ini_col, int tam_fim_col, int cp, int at ) {

         int i, c;

         for ( i = tam_lin_ini; i < tam_lin_fim; i++ ) {

              for ( c = tam_ini_col; c < tam_fim_col; c++ ) {

                   // Coluna, linha, comprimento, altura

                   ctx.clearRect ( c, i, cp, at );

              }

         }

         return 0;

     }

     // //////////////////////////////////////////////////////////////////////////

     // Abaixo a função usada como clock criada por mim

     public static int Sleep_1 ( int x ) {

         ctx.setFont ( Font.font ( "Tahoma", FontWeight.NORMAL, 40 ) );

         Duration duration = Duration.millis ( x );

         do {

              videoTick_1 = new Timeline ( new KeyFrame ( duration,

                        new EventHandler < ActionEvent > ( ) {

                   public void handle ( ActionEvent actionEvent ) {

                        e++;

                        w += str_0.length ( );

                        k = min;

                        str_0 += k;

                        Apaga ( 220, 260, 0, 230 - w, 150, 60 );

                        ctx.setFill ( Color.RED );

                        ctx.fillText ( "0", 218, 250 );

                        if ( k > 9 ) {

                            // Apaga está apagando o "0" acima imprimido

                            // quando o contador chega no 10

                            Apaga ( 220, 260, 190, 300 - w, 150, 60 );

                            a = 25;

                        }

                        if ( k == 60 ) {

                            ctx.setFill ( Color.RED );

                            ctx.fillText ( "00", 218, 250 );

                        }            

                        if ( k <= 59 ) {

                            text1.setStyle ( "-fx-font: normal bold 20px 'serif' " );

                            ctx.setFill ( Color.RED );

                            ctx.fillText ( str_0, 240 - a, 250 );                            

                        }            

                        str_0 = str_0.substring ( 0, w );

                        if ( min == 60 ) {

                            // As variáveis são resetadas para

                            // o retorno do contador

                            min = 0;

                            k = 0;

                            hora++;

                            a = 0;

                        }

                        // //////////////////////////////////////////////////////////

                        f += str_2.length ( );

                        g = hora;

                        str_2 += g;

                        if ( g < 10 ) {

                            ctx.setFill ( Color.RED );

                            ctx.fillText ( "0", 158, 250 );

                        }

                        if ( g > 9 ) {

                            // Apaga está apagando o "0" acima imprimido

                            // quando o contador chega no 10

                            Apaga ( 220, 260, 260, 300 - f, 150, 60 );

                            h = 25;

                        }

                        if ( g == 24 ) {

                            ctx.setFill ( Color.RED );

                            ctx.fillText ( "00", 158, 250 );

                        }

                        ctx.setFill ( Color.RED );

                        ctx.fillText ( ":", 200, 250 );

                        if ( g <= 23 ) {

                            text1.setStyle ( "-fx-font: normal bold 20px 'serif' " );

                            ctx.setFill ( Color.RED );

                            ctx.fillText ( str_2, 180 - h, 250 );

                        }

                        str_2 = str_2.substring ( 0, f );

                        if ( hora == 24 ) {

                            // As variáveis são resetadas para

                            // o retorno do contador

                            hora = 0;

                            g = 0;

                            h = 0;

                        }

                        // //////////////////////////////////////////////////////////

                        b += str_1.length ( );

                        c = seg;

                        str_1 += c;

                        ctx.setFill ( Color.RED );

                        ctx.fillText ( "0", 278, 250 );

                        if ( c > 9 ) {

                            // Apaga está apagando o "0" acima imprimido

                            // quando o contador chega no 10

                            Apaga ( 220, 260, 270, 300 - b, 150, 60 );

                            d = 25;

                        }

                        if ( c <= 59 ) {

                            text1.setStyle ( "-fx-font: normal bold 20px 'serif' " );

                            ctx.setFill ( Color.RED );

                            ctx.fillText ( str_1, 300 - d, 250 );

                        }

                        ctx.setFill ( Color.RED );

                        ctx.fillText ( ":", 260, 250 );

                        str_1 = str_1.substring ( 0, b );

                        seg++;

                        if ( seg == 60 ) {

                            // As variáveis são resetadas para

                            // o retorno do contador

                            seg = 0;

                            c = 0;

                            d = 0;

                            min++;

                        }

                   }

              } ) );

              videoTick_1.setCycleCount ( Animation.INDEFINITE );

              videoTick_1.playFromStart ( );

              return k;

         } while ( true );

     }

     // /////////////////////////////////////////////////////////////////////////

     // Chamando uma função depois de um certo tempo

     public static void Tempo_3 ( ) {

         ctx.setFill ( Color.RED );

         ctx.fillText ( "Criado por: ", 280, 230 );

     }

     public static void Tempo_2 ( ) {

         ctx.setFill ( Color.BLUE );

          ctx.fillText ( "Samuel Lima", 280, 260 );

     }

     public static void Tempo_1 ( ) {

         // Coluna, linha, comprimento, altura

         // Apagando uma linha ou partes

         ctx.clearRect ( 150, 210, 280, 60 );

     }

     // /////////////////////////////////////////////////////////////////////////

     public static int Sleep ( int x, int k ) {

         Task < Integer > close = new Task < Integer > ( ) {

              @Override

              protected Integer call ( ) throws Exception {

                   Thread.sleep ( x );

                   return null;

              }

         };

         close.setOnSucceeded ( c -> {

              if ( k == 1 )

                   Tempo_1 ( );

              if ( k == 2 )

                   Tempo_2 ( );

              if ( k == 3 )

                   Tempo_3 ( );

         } );

         new Thread ( close ).start ( );

         return 0;

     }

     // /////////////////////////////////////////////////////////////////////////

     public static Node But_ton_1 ( ) {

         Button btn_1 = new Button ( "cls" );

         btn_1.setPrefWidth ( 50 );// Largura do botão

         btn_1.setLayoutX ( 22 );// Posição do botão

         btn_1.setPrefHeight ( 20 );// altura do botão

         btn_1.setLayoutY ( 272 );// //Posição do botão

         btn_1.setOnAction ( new EventHandler < ActionEvent > ( ) {

              @Override

              public void handle ( ActionEvent event ) {

                   // Coluna, linha, comprimento, altura

                   // Apagando uma linha ou partes

                   //ctx.clearRect ( 150, 210, 280, 60 );

                   ctx.clearRect ( 50, 60, 380, 260 );

                   //Esconde o textfield

                   textField_1 .setVisible ( false );

              }

         } );

         root.getChildren ( ).add ( btn_1 );

         return btn_1;

     }

     // /////////////////////////////////////////////////////////////////////////

     public static int Menu_Bar ( ) {

         EventHandler < ActionEvent > action = changeTabPlacement ( );

         Menu menu = new Menu ( "Arq" );

         MenuItem top = new MenuItem ( "Exit" );

         top.setOnAction ( action );

         menu.getItems ( ).add ( top );

         MenuItem bottom = new MenuItem ( "Inf" );

         bottom.setOnAction ( action );

         menu.getItems ( ).add ( bottom );

         menuBar.getMenus ( ).add ( menu );

         root.prefHeightProperty ( ).bind ( scene.heightProperty ( ) );

         root.prefWidthProperty ( ).bind ( scene.widthProperty ( ) );

         borderPane.setTop ( menuBar );

         return 0;

     }

     // /////////////////////////////////////////////////////////////////////////

     private static EventHandler < ActionEvent > changeTabPlacement ( ) {

         return new EventHandler < ActionEvent > ( ) {

              public void handle ( ActionEvent event ) {

                   MenuItem mItem = ( MenuItem ) event.getSource ( );

                   String side = mItem.getText ( );

                   int b = 0;

                   if ( "Exit".equalsIgnoreCase ( side ) ) {

                        System.exit ( 0 );

                   } else if ( "Inf".equalsIgnoreCase ( side ) ) {

                        textField_1 .setVisible ( false );

                        textField_2 .setVisible ( false );

                        textField_3 .setVisible ( false );

                        ctx.clearRect ( 50, 60, 380, 260 );

                        But_ton_1 ( );

                        b = 2;

                        Sleep ( 2800, 2 );

                        b = 3;

                        Sleep ( 1800, 3 );

                        b = 4;

                        Sleep ( 1800, b );

                   }

              }

         };

     }

    // ////////////////////////////////////////////////////////////////////////

   public static void limitTextField ( TextField textField, int limit ) {

       UnaryOperator < Change > textLimitFilter = change -> {

            if ( change.isContentChange ( ) ) {

                 int newLength = change.getControlNewText ( ).length ( );

                 if ( newLength > limit ) {

                      String trimmedText = change.getControlNewText ( )

                               .substring ( 0, limit );

                      change.setText ( trimmedText );

                      int oldLength = change.getControlText ( ).length ( );

                      change.setRange ( 0, oldLength );

                 }

            }

            return change;

       };

       textField.setTextFormatter ( new TextFormatter < Object > (

                 textLimitFilter ) );

   }

     // /////////////////////////////////////////////////////////////////////////

     public static int horas ( ) {

         // Textfield      

         hbox_1.setPadding ( new Insets ( 130, 0, 10, 100 ) );

         // Abaixo ajustamos o total de colunas do TextField

         textField_1.setPrefColumnCount ( 2 );

         textField_1.setPromptText("hrs");

         ctx.setFont ( Font.font ( "Tahoma", FontWeight.NORMAL, 12 ) );

         ctx.setFill ( Color.RED );

         ctx.fillText ( "Horas", 100, 120 );

         textField_1.setOnKeyPressed ( new EventHandler < KeyEvent > ( ) {

              @Override         

              public void handle ( KeyEvent event ) {

                   limitTextField ( textField_1, 2 );

                   if ( event.getCode ( ) == KeyCode.ENTER ) {            

                        ctx.setFont ( Font.font ( "Arial", FontWeight.NORMAL, 13 ) );

                        ctx.setFill ( Color.BLUE );

                        // convertendo string para inteiro

                        hora = Integer.parseInt ( textField_1.getText ( ) );

                        if ( Integer.parseInt ( textField_1.getText ( ) ) > -1

                                 && Integer.parseInt ( textField_1.getText ( ) ) < 24 ) {

                            System.out.println ( hora );

                            minutos ( );

                        }

                   }

              }

         } );

         root.getChildren ( ).addAll ( hbox_1 );

         return 0;

     }

     // //////////////////////////////////////////////////////////////////////////

     public static int minutos ( ) {

         // Textfield

         hbox_2.setPadding ( new Insets ( 130, 0, 10, 180 ) );

         // Abaixo ajustamos o total de colunas do TextField

         textField_2.setPrefColumnCount ( 2 );

         textField_2.setPromptText("mts");

         ctx.setFont ( Font.font ( "Tahoma", FontWeight.NORMAL, 12 ) );

         ctx.setFill ( Color.RED );

         ctx.fillText ( "Minutos", 180, 120 );

         textField_2.setOnKeyPressed ( new EventHandler < KeyEvent > ( ) {

              @Override

              public void handle ( KeyEvent event ) {

                   limitTextField ( textField_2, 2 );

                   if ( event.getCode ( ) == KeyCode.ENTER ) {

                        ctx.setFont ( Font.font ( "Arial", FontWeight.NORMAL, 13 ) );

                        ctx.setFill ( Color.BLUE );

                        // convertendo string para inteiro

                        min = Integer.parseInt ( textField_2.getText ( ) );

                        if ( Integer.parseInt ( textField_2.getText ( ) ) > 0

                                 && Integer.parseInt ( textField_2.getText ( ) ) < 60 ) {

                            System.out.println ( min );

                            segundos ( );

                        }

                   }

              }

         } );

         root.getChildren ( ).add ( hbox_2 );

         return 0;

     }

     // //////////////////////////////////////////////////////////////////////////

     public static int segundos ( ) {

         // Textfield

         hbox_3.setPadding ( new Insets ( 130, 0, 10, 260 ) );

         // Abaixo ajustamos o total de colunas do TextField

         textField_3.setPrefColumnCount ( 2 );

         textField_3.setPromptText("sgs");

         ctx.setFont ( Font.font ( "Tahoma", FontWeight.NORMAL, 12 ) );

         ctx.setFill ( Color.RED );

         ctx.fillText ( "Segundos", 260, 120 );

         textField_3.setOnKeyPressed ( new EventHandler < KeyEvent > ( ) {

              @Override

              public void handle ( KeyEvent event ) {

                   limitTextField ( textField_3, 2 );

                   if ( event.getCode ( ) == KeyCode.ENTER ) {

                        ctx.setFont ( Font.font ( "Arial", FontWeight.NORMAL, 13 ) );

                        ctx.setFill ( Color.BLUE );

                        // convertendo string para inteiro

                        seg = Integer.parseInt ( textField_3.getText ( ) );

                        if ( Integer.parseInt ( textField_3.getText ( ) ) > 0

                                 && Integer.parseInt ( textField_3.getText ( ) ) < 60 ) {

                            System.out.println ( seg );

                            System.out.println ( "RELÓGIO DIGITAL EM JAVA" );

                            Sleep_1 ( 1000 );

                            textField_1 .setVisible ( false );

                            textField_2 .setVisible ( false );

                            textField_3 .setVisible ( false );

                            ctx.clearRect ( 50, 60, 380, 260 );

                        }

                   }

              }

         } );

         root.getChildren ( ).add ( hbox_3 );

         return 0;

     }

     // /////////////////////////////////////////////////////////////////////////

     public void start ( Stage stage ) {

         stage.setTitle ( "RELÓGIO DIGITAL EM JAVAFX" );   

         // Dando uns efeitos na moldura

         root.setStyle ( "-fx-padding: 5;" + "-fx-border-style: solid inside;"

                   + "-fx-border-width: 18;" + "-fx-border-insets: 5;"

                   + "-fx-border-radius: 5;" + "-fx-border-color: blue;" );

         //Com este comando a tela não se espande

         stage.setResizable ( false );

         Menu_Bar ( );

         ctx.setFill ( Color.RED );

         ctx.setFont ( Font.font ( "Serif", FontWeight.BOLD, 20 ) );

         ctx.fillText ( "RELÓGIO DIGITAL EM JAVAFX", 100, 50 );

         ctx.setFont ( Font.font ( "Arial", FontWeight.NORMAL, 15 ) );

         ctx.setFill ( Color.BLACK );

         ctx.fillText ( "Vamos acertar nosso relógio", 120, 100 );

         root.getChildren ( ).add ( canvas );

         horas ( );

         // Configurando o local exato do menu

         borderPane.setPadding ( new Insets ( 23, 0, 5, 23 ) );

         root.getChildren ( ).addAll ( borderPane );

         stage.setScene ( scene );

         stage.show ( );

     }

     // /////////////////////////////////////////////////////////////////////////

     public static void main ( String [ ] args ) {

         Application.launch ( args );

     }

}