我目前有一个有效的代码，但是全部都在一个文件中，而且很长。 我不确定如何将代码分解成较小的部分并使用它们创建类。 我尝试研究JavaFX类，但没有提出任何全面的内容。 我是否要制作一个新的Java类文件？ 如何在主类文件中调用它？ 我的菜单按钮尝试上一堂课，但是滑钮出现错误。
任何帮助，我们将不胜感激！
package paint;
import java.awt.image.RenderedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import javafx.application.Application;
import javafx.embed.swing.SwingFXUtils;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.canvas.Canvas;
import javafx.scene.canvas.GraphicsContext;
import javafx.scene.control.Button;
import javafx.scene.control.ColorPicker;
import javafx.scene.control.Label;
import javafx.scene.control.ToggleButton;
import javafx.scene.control.ToggleGroup;
import javafx.scene.image.Image;
import javafx.scene.image.WritableImage;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.scene.shape.Line;
import javafx.scene.shape.Rectangle;
import javafx.stage.FileChooser;
import javafx.stage.Stage;
import javax.imageio.ImageIO;
import javafx.scene.shape.Circle;
import javafx.scene.control.Slider;
public class Paint extends Application {
@Override
public void start(Stage primaryStage) {
//Create menu buttons
ToggleButton drawbtn = new ToggleButton("Draw");
ToggleButton linebtn = new ToggleButton("Line");
ToggleButton erasebtn = new ToggleButton("Eraser");
ToggleButton recbtn = new ToggleButton("Rectangle");
ToggleButton circbtn = new ToggleButton("Circle");
ToggleButton[] toolsArr = {drawbtn, linebtn, erasebtn, recbtn, circbtn};
ToggleGroup tools = new ToggleGroup();
for (ToggleButton tool : toolsArr) {
tool.setMinWidth(90);
tool.setToggleGroup(tools);
}
//Initializing Color Picker and Color fills selections
ColorPicker cpLine = new ColorPicker(Color.BLACK);
ColorPicker cpFill = new ColorPicker(Color.TRANSPARENT);
//Creating label names
Label line_color = new Label("Line Color");
Label fill_color = new Label("Fill Color");
//Creating line width selector
Slider slider = new Slider(1, 25, 3);
slider.setShowTickLabels(true);
slider.setShowTickMarks(true);
Button saveas = new Button("Save As");
Button open = new Button("Open");
//Menu with buttons
VBox btns = new VBox(10);
btns.getChildren().addAll(drawbtn, linebtn, line_color, cpLine, fill_color, cpFill, open, saveas, erasebtn, recbtn, circbtn, slider);
btns.setPadding(new Insets(5));
btns.setPrefWidth(100);
//Setting up the blank canvas
Canvas canvas = new Canvas(1080, 790);
GraphicsContext gc;
gc = canvas.getGraphicsContext2D();
gc.setLineWidth(1);
Line line = new Line();
Rectangle rec = new Rectangle();
Circle circ = new Circle();
//Was the mouse button pressed on the canvas..
canvas.setOnMousePressed(e->{
if(drawbtn.isSelected()) { //While the draw button is selected
gc.setStroke(cpLine.getValue());
gc.beginPath();
gc.lineTo(e.getX(), e.getY());
}
else if(linebtn.isSelected()) { //While the line button is selected
gc.setStroke(cpLine.getValue());
line.setStartX(e.getX()); //Start line at this x value
line.setStartY(e.getY()); //Start line at this y value
}
else if(erasebtn.isSelected()) { //While the eraser button is selected
double lineWidth = gc.getLineWidth();
gc.clearRect(e.getX() - lineWidth / 2, e.getY() - lineWidth / 2, lineWidth, lineWidth);
}
else if(recbtn.isSelected()) { //While the rectangle button is selected
gc.setStroke(cpLine.getValue());
gc.setFill(cpFill.getValue()); //Fill the rectangle with fill color
rec.setX(e.getX()); //Start rectangle at this x
rec.setY(e.getY()); //Start rectangle at this y
}
else if(circbtn.isSelected()) {
gc.setStroke(cpLine.getValue());
gc.setFill(cpFill.getValue());
circ.setCenterX(e.getX());
circ.setCenterY(e.getY());
}
});
//Draws and creates line based on mouse clicks
canvas.setOnMouseDragged(e->{
if(drawbtn.isSelected()) {
gc.lineTo(e.getX(), e.getY());
gc.stroke();
}
//Erases areas where the mouse is clicked and dragged over
else if(erasebtn.isSelected()){
double lineWidth = gc.getLineWidth();
gc.clearRect(e.getX() - lineWidth / 2, e.getY() - lineWidth / 2, lineWidth, lineWidth);
}
});
//Was the mouse button released...
canvas.setOnMouseReleased(e->{
if(drawbtn.isSelected()) { //while the draw button was selcted
gc.lineTo(e.getX(), e.getY());
gc.stroke();
gc.closePath();
}
else if(linebtn.isSelected()) { //while the line button was selcted
line.setEndX(e.getX());
line.setEndY(e.getY());
gc.strokeLine(line.getStartX(), line.getStartY(), line.getEndX(), line.getEndY());
}
else if(erasebtn.isSelected()) { //while the erase button was selcted
double lineWidth = gc.getLineWidth();
gc.clearRect(e.getX() - lineWidth / 2, e.getY() - lineWidth / 2, lineWidth, lineWidth);
}
else if(recbtn.isSelected()) { //while the rectangle button was selcted
rec.setWidth(Math.abs((e.getX() - rec.getX())));
rec.setHeight(Math.abs((e.getY() - rec.getY())));
//If X value of rectangle is greater than the X value of e, make e = rectangle value
if(rec.getX() > e.getX()) {
rec.setX(e.getX());
}
//If Y value of rectangle is greater than the Y value of e, make e = rectangle value
if(rec.getY() > e.getY()) {
rec.setY(e.getY());
}
//Filling the rectangle with color
gc.fillRect(rec.getX(), rec.getY(), rec.getWidth(), rec.getHeight());
gc.strokeRect(rec.getX(), rec.getY(), rec.getWidth(), rec.getHeight());
}
else if(circbtn.isSelected()) {
circ.setRadius((Math.abs(e.getX() - circ.getCenterX()) + Math.abs(e.getY() - circ.getCenterY())) / 2);
if(circ.getCenterX() > e.getX()) {
circ.setCenterX(e.getX());
}
if(circ.getCenterY() > e.getY()) {
circ.setCenterY(e.getY());
}
gc.fillOval(circ.getCenterX(), circ.getCenterY(), circ.getRadius(), circ.getRadius());
gc.strokeOval(circ.getCenterX(), circ.getCenterY(), circ.getRadius(), circ.getRadius());
}
});
//Setting up the color picker for line/drawing
cpLine.setOnAction(e->{
gc.setStroke(cpLine.getValue());
});
//Setting up the color fill
cpFill.setOnAction(e->{
gc.setFill(cpFill.getValue());
});
//Setting up the width slider
slider.valueProperty().addListener(e->{
double width = slider.getValue();
gc.setLineWidth(width);
});
//Open a file from desktop
open.setOnAction((e)->{
FileChooser openFile = new FileChooser();
openFile.setTitle("Open File");
File file = openFile.showOpenDialog(primaryStage);
if (file != null) {
try {
InputStream io = new FileInputStream(file);
Image img = new Image(io);
gc.drawImage(img, 0, 0);
} catch (IOException ex) {
System.out.println("Error!");
}
}
});
//Save Canvas
saveas.setOnAction((e)->{
FileChooser savefile = new FileChooser();
savefile.setTitle("Save File");
File file = savefile.showSaveDialog(primaryStage);
if (file != null) {
try {
WritableImage writableImage = new WritableImage(1080, 790);
canvas.snapshot(null, writableImage);
RenderedImage renderedImage = SwingFXUtils.fromFXImage(writableImage, null);
ImageIO.write(renderedImage, "png", file);
} catch (IOException ex) {
System.out.println("Error!");
}
}
});
BorderPane pane = new BorderPane();
pane.setRight(btns);
pane.setCenter(canvas);
Scene scene = new Scene(pane, 1200, 800); //Sets size of window
primaryStage.setTitle("Paint");
primaryStage.setScene(scene);
primaryStage.show();
}
//Launch Program
public static void main(String[] args) {
launch(args);
}
}