I'm making an application that has a drawing board where you draw with your mouse, it draws ontop of an Label in a BUfferedImage. What I'm trying to implement right now is an eraser, the problem is I cannot find anywhere help to make an eraser to clearRect() to an alpha background. (I cannot have a defined color background since the user can change the background to any image he wants). To sum up:
How can you erase/overwrite Graphics2D pixels with alpha pixels? The way i found was with clearRect but you need to specify a background color.
The following is my DrawBoard class which constains everything to draw.
public class DrawBoard extends JPanel implements MouseListener, MouseMotionListener{
public JLabel status;
private JLabel imgLabel; // this is where the drawing happens
public Point pstart, pfinish;
private List<Point> points = new ArrayList<Point>();
private List<BufferedImage> lines = new ArrayList<BufferedImage>();
private static final int BI_WIDTH = 1024;
private static final int BI_HEIGHT = 800;
private static int STROKESIZE = 7;
private BufferedImage bImage = new BufferedImage(BI_WIDTH, BI_HEIGHT,
BufferedImage.TYPE_INT_ARGB);
public Color currentColor;
public static boolean eraser = false;
private int xX1, yY1;
public DrawBoard(){
Graphics2D g2d = bImage.createGraphics();
g2d.dispose();
Dimension size = getPreferredSize();
size.setSize(1024,800); //w, h
setPreferredSize(size);
//status = new JLabel("default");
//add(status, BorderLayout.SOUTH);
addMouseListener(this);
addMouseMotionListener(this);
imgLabel = new JLabel(new ImageIcon(bImage)) {
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
paintInLabel(g);
}
};
imgLabel.setOpaque(false);
setOpaque(false);
add(imgLabel, BorderLayout.CENTER);
}
private void paintInLabel(Graphics g) {
Graphics2D g2d = (Graphics2D) g;
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
g2d.setColor(getColor()); // this colour is when mouse is pressed
g2d.setStroke(new BasicStroke(STROKESIZE));
if (points.size() < 2) {
return;
}
for (int i = 1; i < points.size(); i++) {
int x1 = points.get(i - 1).x;
int y1 = points.get(i - 1).y;
int x2 = points.get(i).x;
int y2 = points.get(i).y;
g2d.drawLine(x1, y1, x2, y2);
}
}
#Override
public void mouseExited(MouseEvent e){
}
#Override
public void mouseEntered(MouseEvent e){
}
#Override
public void mouseMoved(MouseEvent e){
}
// Where the drawing happens
#Override
public void mousePressed(MouseEvent e) {
//status.setText("you pressed down the mouse");
xX1 = e.getX();
yY1 = e.getY();
points.add(e.getPoint());
}
#Override
public void mouseDragged(MouseEvent e) {
//status.setText("you draged the mouse");
points.add(e.getPoint());
imgLabel.repaint();
}
#Override
public void mouseReleased(MouseEvent e) {
//status.setText("you release the mouse click");
Graphics2D g2d = bImage.createGraphics();
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
g2d.setColor(getColor()); // this is the final colour
g2d.setStroke(new BasicStroke(STROKESIZE));
if (points.size() >= 2) {
for (int i = 1; i < points.size(); i++) {
int x1 = points.get(i - 1).x;
int y1 = points.get(i - 1).y;
int x2 = points.get(i).x;
int y2 = points.get(i).y;
g2d.drawLine(x1, y1, x2, y2);
}
}
g2d.dispose();
points.clear();
imgLabel.repaint();
}
// End of where the drawing happens
public void clearDrawBoard() {
}
private Color getColor() {
return ColourToolbar.selectedColor;
}
private void setColor(Color col){
this.currentColor = col;
}
#Override
public void mouseClicked(MouseEvent e) {
//throw new UnsupportedOperationException("Not supported yet.");
}
}
You should set a custom Composite for your Graphics2D, specifically AlphaComposite.Clear before drawing the rectangle. Don't forget to reset the composite to the default (SRC_OVER) when you are done, because the same Graphics object will be reused to paint other components.
Related
I'm trying to make it when you click the cameraButton, the graphics show, but when clicked again, it closes.
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
int camButtonWidth = 500;
int camButtonHeight = 33;
int camButtonX = (width - camButtonWidth) / 2;
int camButtonY = (height - camButtonHeight) - 5;
int camWidth = width - 50;
int camHeight = (height - (camButtonHeight * 2)) - 10;
int camX = (width - camWidth) / 2;
int camY = ((height - camHeight) - camButtonHeight) / 2;
Graphics2D g1 = (Graphics2D) g;
Graphics2D g2 = (Graphics2D) g;
Graphics2D g3 = (Graphics2D) g;
RoundRectangle2D camButton = new RoundRectangle2D.Double(camButtonX, camButtonY, camButtonWidth, camButtonHeight, 25, 25);
RoundRectangle2D cameras = new RoundRectangle2D.Double(camX, camY, camWidth, camHeight, 25, 25);
// Background
g1.setColor(Color.BLACK);
g1.fillRect(0, 0, width, height);
addMouseListener(new MouseListener() {
#Override
public void mouseClicked(MouseEvent e) {
if (camButton.contains(e.getPoint())) {
camUp = !camUp;
repaint();
}
}
#Override
public void mousePressed(MouseEvent e) {
}
#Override
public void mouseReleased(MouseEvent e) {
}
#Override
public void mouseEntered(MouseEvent e) {
}
#Override
public void mouseExited(MouseEvent e) {
}
});
// Camera Button
g2.setColor(camColor);
g2.fill(camButton);
paintCameras = camUp;
// Cameras
g3.setColor(camColor);
if (paintCameras) {
g3.fill(cameras);
}
repaint();
}
Try to change make it when you click the camera button, a graphics object shows, but when clicked again, it closes.
To get this sort of program to work you should:
Create your MouseListener in code that is only called once, such as within a constructor
Create an instance field in the class to represent the camera button, such as a Rectangle or RoundRectangle2D and give it a viable object reference
In the mouse listener, toggle the state of a boolean variable if a click occurs within the shape that represents the camera button, e.g., camUp = !camUp; as you're doing
And then call repaint().
In the paintComponent method, check the state of the boolearn variable with an if statement, and if true, draw the image inside the if statement.
Keep the mouse listener and the painting code separate and in separate methods (or constructor).
Never call repaint() within a painting method as that will cause an uncontrolled animation. If you need a Swing animation, then use a Swing Timer so that you can fully control it. I don't see the need for it here.
For example:
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.awt.image.BufferedImage;
import javax.swing.*;
#SuppressWarnings("serial")
public class GraphicsExample extends JPanel {
private static final int IMG_WIDTH = 400;
private static final int PREF_W = (3 * IMG_WIDTH) / 2;
private static final int PREF_H = PREF_W;
private static final Color BTN_COLOR = Color.RED;
private static final Color HOVER_COLOR = new Color(255, 100, 100);
private static final Color BTN_CLK_COLOR = new Color(180, 0, 0);
private static final int IMG_X = IMG_WIDTH / 2;
private static final int IMG_Y = IMG_X;
private double camX = 10;
private double camY = camX;
private double camWidth = 200;
private double camHeight = 80;
private Color buttonColor = Color.RED;
private RoundRectangle2D cameraButton = new RoundRectangle2D.Double(camX, camY, camWidth, camHeight, 25, 25);
private Image img;
private boolean showImage = false;
private JCheckBox toggleModeChkBox = new JCheckBox("Toggle Mode");
// private boolean toggleMode = true;
public GraphicsExample() {
add(toggleModeChkBox);
setPreferredSize(new Dimension(PREF_W, PREF_H));
img = createMyImage();
MouseAdapt mouseAdapt = new MouseAdapt();
addMouseListener(mouseAdapt);
addMouseMotionListener(mouseAdapt);
}
private Image createMyImage() {
BufferedImage img = new BufferedImage(IMG_WIDTH, IMG_WIDTH, BufferedImage.TYPE_INT_ARGB);
Graphics2D g2 = img.createGraphics();
g2.setPaint(new GradientPaint(0, 0, Color.RED, 100, 100, Color.BLUE, true));
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
int gap = 10;
g2.fillOval(gap, gap, IMG_WIDTH - 2 * gap, IMG_WIDTH - 2 * gap);
g2.dispose();
return img;
}
private class MouseAdapt extends MouseAdapter {
#Override
public void mousePressed(MouseEvent e) {
if (cameraButton.contains(e.getPoint())) {
buttonColor = BTN_CLK_COLOR;
if (toggleModeChkBox.isSelected()) {
showImage = !showImage;
} else {
showImage = true;
}
} else {
buttonColor = BTN_COLOR;
}
repaint();
}
#Override
public void mouseReleased(MouseEvent e) {
if (cameraButton.contains(e.getPoint())) {
buttonColor = HOVER_COLOR;
} else {
buttonColor = Color.RED;
}
if (!toggleModeChkBox.isSelected()) {
showImage = false;
}
repaint();
}
#Override
public void mouseMoved(MouseEvent e) {
if (cameraButton.contains(e.getPoint())) {
buttonColor = HOVER_COLOR;
} else {
buttonColor = Color.RED;
}
if (!toggleModeChkBox.isSelected()) {
showImage = false;
}
repaint();
}
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2.setColor(buttonColor);
g2.fill(cameraButton);
if (showImage) {
int x = (getWidth() - IMG_WIDTH) / 2;
int y = (getHeight() - IMG_WIDTH) / 2;
g2.drawImage(img, x, y, this);
}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(() -> {
GraphicsExample mainPanel = new GraphicsExample();
JFrame frame = new JFrame("GUI");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.add(mainPanel);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
});
}
}
I have added 2 JComponent to JPanel.Both these JComponent have custom painted objects on them i.e multiple Circles and multiple Line2Ds.The dimensions of both these jcomponent's are set to the size of the screen which is required.When I add them to JPanel,the mouselisteners are not working.However if I comment one of them then that listener starts working.
public class MapXMLBuilder extends JFrame {
public void initialize() {
panel = new Jpanel();
addLine();//ading lines
addCircle();//adding cirlces
add(panel)
}
private void addLine() {
mDrawLine = new DrawLine(panel);
mDrawCircle.setDimensions(screenWidth, screenWidth);
panel.add(mDrawLine); //adding JComponent1 to panel
for (int i = 0; i < 10; i++) { //adding 10 circles
mDrawLine.addLine(new Point2D.Double(x, y));
}
}
private void addCircle() {
mDrawCircle = new DrawCircle(panel);
mDrawCircle.setDimensions(screenWidth, screenWidth);
panel.add(mDrawCircle); //adding JComponent1 to panel
for (int i = 0; i < 10; i++) { //adding 10 circles
mDrawCircle.addCircle(new Point2D.Double(x, y));
}
}
}
public class DrawLine extends JComponent {
public DrawLine(JPanel jpanel) {
lineList = new ArrayList();
addMouseListener(mouseAdapter);
addMouseMotionListener(mouseAdapter);
setBackground(Color.white);
}
public void addLine(int x1, int y1, int x2, int y2, Color color) {
Shape currentShape = new Line2D.Float(x1, y1, x2, y2);
lineList.add(currentShape);
repaint();
}
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g;
g2d.setPaint(Color.BLACK);
for (Shape shape: lineList) {
if (shapes != null && shapes.size() > 0) {
g2d.setColor(Color.YELLOW);
g2d.draw(shape);
}
}
}
public void setDimensions(int width, int height) {
setSize(new Dimension(width, height));
}
}
public class DrawCircle extends JComponent {
public DrawCircle(JPanel jpanel) {
circleList = new ArrayList();
addMouseListener(mouseAdapter);
addMouseMotionListener(mouseAdapter);
setBackground(Color.white);
}
public void addCircle(Point2D p) {
Ellipse2D e = new Ellipse2D.Double(p.getX(), p.getY(), 5, 5);
circleList.add(e);
selectedPoint = null;
repaint();
}
public void setDimensions(int width, int height) {
setSize(new Dimension(width, height));
}
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
int diameter = 75;
Ellipse2D e;
Color color;
for (int j = 0; j < circleList.size(); j++) {
e = (Ellipse2D) circleList.get(j);
float alpha = 0.75f;
color = new Color(1, 0, 0, alpha); //Red
g2.setPaint(color);
Ellipse2D.Double circle = new Ellipse2D.Double(e.getX(), e.getY(), diameter, diameter);
g2.fill(circle);
}
}
}
You can forward the event from one to the other. Try something like this:
firstComponent.addMouseListener(new MouseAdapter(){
public void mouseClicked(MouseEvent event){
// forward the event
secondComponent.dispatchEvent(event);
// handle the code here
}
});
secondComponent.addMouseListener(// etc.
I have some issues with my paint program in Java.
I have a JComboBox where I can choose to draw either a rectangle or by freehand. The objects are added to an ArrayList. I want to be able to switch between drawing a rectangle and by free hand, and then back to drawing a rectangle, and then by free hand... and so on.
If I do that as the code looks like now, it first draws rectangles fine and then when I switch to free hand it draws lines fine, but then when I switch back to rectangles it still draws lines (or sometimes lines together with weird looking rectangles). The more I switch the weirder it gets.
Can anyone see what is wrong with the code, because I can't?
public abstract class Draw {
public int startX, startY, endX, endY, width, height, w, h;
public String color = "Black";
public Draw(int startX, int startY, int width, int height) {
this.startX = startX;
this.startY = startY;
this.width = width;
this.height = height;
}
public abstract void draw(Graphics2D g);
public int getX() {
return startX;
}
public void setX(int startX) {
this.startX = startX;
}
public int getY() {
return startY;
}
public void setY(int startY) {
this.startY = startY;
}
public int getWidth() {
return width;
}
public void setWidth(int width) {
this.width = width;
}
public int getHeight() {
return height;
}
public void setHeight(int height) {
this.height = height;
}
public void setColor(String color) {
this.color = color;
}
}
public class Rectangle extends Draw {
public Rectangle(int x, int y, int width, int height) {
super(x, y, width, height);
}
#Override
public void draw(Graphics2D g2) {
g2.drawRect(getX(), getY(), getWidth(), getHeight());
}
}
public class FreeHand extends Draw {
public FreeHand(int x, int y, int width, int height) {
super(x, y, width, height);
}
#Override
public void draw(Graphics2D g2) {
g2.drawLine(getX(), getY(), getWidth(), getHeight());
}
}
public class PaintProgram extends JFrame implements ActionListener {
public ArrayList<Draw> shapeList = new ArrayList<>();
int startX, startY, endX, endY, w, h;
private JPanel topPanel;
private JPanel bottomPanel;
private JPanel leftPanel;
private JPanel rightPanel;
private JComboBox comboBox;
private final String[] boxOptions = new String[] {"Rectangle", "Freehand"};
Container cp = getContentPane();
private int count = 0;
public JavaApplication30(String title) {
super(title);
this.setLayout(new BorderLayout());
this.setDefaultCloseOperation(DO_NOTHING_ON_CLOSE);
this.setLocationRelativeTo(null);
this.setSize(840, 500);
this.initComponents();
this.setVisible(true);
}
private void initComponents() {
cp.setBackground(Color.WHITE);
comboBox = new JComboBox(boxOptions);
topPanel = new JPanel();
bottomPanel = new JPanel(new GridLayout(1,2));
rightPanel = new JPanel(new FlowLayout(FlowLayout.RIGHT));
leftPanel = new JPanel(new FlowLayout(FlowLayout.LEFT));
comboBox.setSelectedIndex(0);
comboBox.addActionListener(this);
topPanel.setPreferredSize(new Dimension(0,40));
bottomPanel.setPreferredSize(new Dimension(0,30));
bottomPanel.setBackground(Color.LIGHT_GRAY);
topPanel.add(comboBox);
bottomPanel.add(leftPanel);
bottomPanel.add(rightPanel);
this.add(topPanel, BorderLayout.PAGE_START);
this.add(bottomPanel, BorderLayout.PAGE_END);
}
#Override
public void paint(Graphics g) {
if(count == 0) {
cp.repaint();
}
Graphics2D g2 = (Graphics2D) g;
for (Draw d : shapeList) {
d.draw(g2);
}
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2.setStroke(new BasicStroke(1));
if (startX != 0 && startY != 0 && endX != 0 && endY != 0) {
int width = Math.abs(startX - endX);
int height = Math.abs(startY - endY);
int minX = Math.min(startX, endX);
int minY = Math.min(startY, endY);
Rectangle r = new Rectangle(minX, minY, width, height);
g2.setPaint(Color.WHITE);
g2.fillRect(r.getX(), r.getY(), r.getWidth(), r.getHeight());
r.setColor(pickedColor);
r.draw(g2);
}
}
#Override
public void actionPerformed(ActionEvent e) {
count++;
if (e.getSource().equals(comboBox)) {
JComboBox cb = (JComboBox)e.getSource();
if (cb.getSelectedItem().equals("Rectangle")) {
this.addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent e) {
startX = e.getX();
startY = e.getY();
endX = startX;
endY = startY;
repaint();
}
#Override
public void mouseReleased(MouseEvent e) {
endX = e.getX();
endY = e.getY();
int width = Math.abs(startX - endX);
int height = Math.abs(startY - endY);
int minX = Math.min(startX, endX);
int minY = Math.min(startY, endY);
Rectangle r = new Rectangle(minX, minY, width, height);
shapeList.add(r);
r.setColor(pickedColor);
startX = 0;
startY = 0;
endX = 0;
endY = 0;
repaint();
}
});
this.addMouseMotionListener(new MouseMotionAdapter() {
#Override
public void mouseDragged(MouseEvent e) {
endX = e.getX();
endY = e.getY();
repaint();
}
});
}
else if (cb.getSelectedItem().equals("Freehand")) {
this.addMouseListener(new MouseAdapter() {
#Override
public void mousePressed(MouseEvent e) {
startX = e.getX();
startY = e.getY();
addCoordinate(startX, startY);
}
});
this.addMouseMotionListener(new MouseMotionAdapter() {
#Override
public void mouseDragged(MouseEvent e) {
Graphics g = getGraphics();
Graphics2D g2 = (Graphics2D) g;
FreeHand fh = new FreeHand(startX, startY, e.getX(), e.getY());
shapeList.add(fh);
fh.setColor(pickedColor);
fh.draw(g2);
startX = e.getX();
startY = e.getY();
}
});
}
}
}
public static void main(String args[]) {
new PaintProgram("Paint");
}
}
You add MouseListeners but you do not remove them. Every time you choose something in the combobox, a new listener is added. So when you draw something every listener is applied and weird stuff will happen.
You should remove the previous MouseListener before adding a new one. You might have to remember it in an instance variable.
Alternatively, you can add all listeners at the start, but check the value of the combobox inside the listener. If the value does not correspond to what the listener is for, it should do nothing.
EDIT: Here is how you can remove all listeners
for (MouseListener listener : this.getMouseListeners()) {
this.removeMouseListener(listener);
}
for (MouseMotionListener listener : this.getMouseMotionListeners()) {
this.removeMouseMotionListener(listener);
}
Put this code in before you add the new listeners in the actionPerformed() method
As was stated here and here previously, do not add MouseListeners within your ActionListener, instead, create a single MosueListener and determine what you want to do based on the currently selected item.
Basically, you keep adding a new MouseListener each time actionPerformed is called...they are accumulating...
A solution would be to use a single MouseListener and a factory of some kind...
Start by defining the factory interface...
public interface DrawFactory {
public Draw createDrawing(int x, int y, int width, int height, Color color);
public void addPoint(Draw draw, int x, int y);
}
Create a implementation of the factory for each type of shape you want to draw...
public class RectangleFactory implements DrawFactory {
#Override
public Draw createDrawing(int x, int y, int width, int height, Color color) {
return new Rectangle(x, y, width, height);
}
#Override
public void addPoint(Draw draw, int x, int y) {
// Does nothing...
}
#Override
public boolean isMutable() {
return false;
}
#Override
public String getName() {
return "Rectangle";
}
#Override
public String toString() {
return getName();
}
}
public class FreeHandFactory implements DrawFactory {
#Override
public Draw createDrawing(int x, int y, int width, int height, Color color) {
return new FreeHand(x, y, width, height);
}
#Override
public void addPoint(Draw draw, int x, int y) {
if (draw instanceof FreeHand) {
FreeHand fh = (FreeHand)draw;
//fh.addPoint(x, y);
}
}
#Override
public boolean isMutable() {
return true;
}
#Override
public String getName() {
return "Free Hand";
}
#Override
public String toString() {
return getName();
}
}
Next, create a custom component that extends from JPanel which will act as the primary drawing surface, this will be repsonsible for monitoring the MouseLstener and painting the Draw instances, as was mentioned here
public class DrawSurface extends JPanel {
private DrawFactory factory;
private Draw currentDraw;
private List<Draw> shapeList = new ArrayList<>();
private Color drawColor;
public DrawSurface() {
shapeList = new ArrayList<>(25);
MouseAdapter ma = new MouseAdapter() {
private Point pressPoint;
#Override
public void mousePressed(MouseEvent e) {
pressPoint = e.getPoint();
}
#Override
public void mouseReleased(MouseEvent e) {
DrawFactory factory = getDrawFactory();
if (factory != null) {
Point p = e.getPoint();
if (factory.isMutable() && currentDraw != null) {
factory.addPoint(currentDraw, p.x, p.y);
} else {
int x = Math.min(p.x, pressPoint.x);
int y = Math.min(p.y, pressPoint.y);
int width = Math.abs(p.x - pressPoint.x);
int height = Math.abs(p.y - pressPoint.y);
Draw draw = factory.createDrawing(x, y, width, height, getDrawColor());
shapeList.add(draw);
if (factory.isMutable()) {
currentDraw = draw;
}
}
}
}
};
}
public DrawFactory getDrawFactory() {
return factory;
}
public void setDrawFactory(DrawFactory factory) {
this.factory = factory;
currentDraw = null;
}
public Color getDrawColor() {
return drawColor;
}
public void setDrawColor(Color drawColor) {
this.drawColor = drawColor;
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
for (Draw draw : shapeList) {
draw.draw(g2d);
}
g2d.dispose();
}
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}
}
Next, change your boxOptions from String to DrawFactory, this will make it easier to determine which factory you should use. Don't forget to add a reference to the DrawSurface
private final DrawFactory[] boxOptions = new DrawFactory[]{new RectangleFactory(), new FreeHandFactory()};
private DrawSurface drawSurface;
In your initComponents create a new instance of DrawSurface and add it to your frame...
private void initComponents() {
//...
drawSurface = new DrawSurface();
this.add(drawSurface);
}
Change your actionPerformed method to look more like...
#Override
public void actionPerformed(ActionEvent e) {
count++;
drawSurface.setDrawFactory((DrawFactory)comboBox.getSelectedItem());
}
Not sure how you are determining the current color as you example code is incomplete, but basically, you want to set the drawColor of the DrawSurface similarly.
Get rid of the paint method in the PaintProgram as you shouldn't be overriding the paint method of top level containers, which you've been advised against at least once, if not twice.
The point of all this is simple, when you want to add a new "drawing shape", you create a Draw and DrawFactory for it and add the factory to the combo box ... work done...
I'm making a music/drawing application which you free draw lines with your mouse and a TrackBar passes horizontally through it and reads the lines and uses the x and y coordinate to modify music.
The problem I'm having is that TrackBar class is a JPanel and DrawBoard class is a JPanel which I add inside a Frame. But which ever is on-top is the one that will show, what I want is for them to both show, and the TrackBar to pass on top of the lines drawn.
Below Is the source code of this 3 classes and took out some unncesesary code:
The MainFrame class where I add them (with the current setup the TrackBar doesnt appear but the Drawing board appears since it overlaps it):
public class MainFrame extends JFrame {
public static ColourToolbar colourBar;
public static TrackBar tb;
public MainFrame(){
super("VIPE by Prestige WorldWide");
// Top colour toolbar for tones
colourBar = new ColourToolbar();
this.getContentPane().add(colourBar, BorderLayout.NORTH);
// This class ImagePanel is a JPanel which I overite the paintCOmponent to have background
ImagePanel bg = new ImagePanel();
bg.setLayout(new BorderLayout());
Dimension size = getPreferredSize();
size.setSize(1024,800); //w, h
bg.setPreferredSize(size);
this.getContentPane().add(bg, BorderLayout.CENTER);
// I add the TrackBar to the ImagePanel since its the Background
tb = new TrackBar();
bg.add(tb, BorderLayout.CENTER);
// I add the drawing board but It will overlap the Trackbar
DrawBoard dboard = new DrawBoard();
bg.add(dboard, BorderLayout.CENTER);
// The control toolbar where the settings and control buttons are.
Toolbar toolBar = new Toolbar();
this.getContentPane().add(toolBar, BorderLayout.SOUTH);
}
public static void main(String[] args){
MainFrame frame = new MainFrame();
frame.setBackground(Color.WHITE);
frame.setSize(1024,768);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setResizable(false);
//frame.pack();
frame.setVisible(true);
}
}
Now the TrackBar class:
public class TrackBar extends JPanel{
private TrackBarAction tba = new TrackBarAction(this);
public static int TIME = 9;
public Timer t = new Timer(TIME, tba);
public static double x = 0, y = 0, velX = 1.0, velY = 0;
private int SKIP = 120;
public TrackBar(){
this.setOpaque(false);
}
#Override
public void paintComponent(Graphics g){
super.paintComponent(g);
Graphics2D g2d = (Graphics2D)g;
//g2d.drawRect((int)x, (int)y, 10, 800);
Rectangle2D r2d = new Rectangle2D.Double(x, y, 8.0, 800.0); // x,x, w, h
g2d.setPaint(Color.DARK_GRAY);
g2d.fill(r2d);
g2d.draw(r2d);
}
public void reset(){
t.stop();
x = 0;
y = 0;
velX = 0.5;
velY = 0;
this.repaint();
}
public void skipForward(){
if(x+SKIP <= 1024){
x += SKIP;
} else {
x = 1024 - x;
}
this.repaint();
}
public void skipBackwards(){
if(x-SKIP >= 0){
x -= SKIP;
} else {
x = 0;
}
this.repaint();
}
}
And now the DrawBoard class:
public class DrawBoard extends JPanel implements MouseListener, MouseMotionListener{
(..)
public Color currentColor;
public static boolean eraser = false;
private int xX1, yY1;
public DrawBoard(){
Graphics2D g2d = bImage.createGraphics();
g2d.dispose();
Dimension size = getPreferredSize();
size.setSize(1024,800); //w, h
setPreferredSize(size);
//status = new JLabel("default");
//add(status, BorderLayout.SOUTH);
addMouseListener(this);
addMouseMotionListener(this);
imgLabel = new JLabel(new ImageIcon(bImage)) {
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
paintInLabel(g);
}
};
imgLabel.setOpaque(false);
setOpaque(false);
add(imgLabel, BorderLayout.CENTER);
}
private void paintInLabel(Graphics g) {
if(!eraser){
Graphics2D g2d = (Graphics2D) g;
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2d.setColor(getColor()); // this colour is when mouse is pressed
g2d.setStroke(new BasicStroke(STROKESIZE));
if (points.size() < 1) {
return;
}
for (int i = 1; i < points.size(); i++) {
int x1 = points.get(i - 1).x;
int y1 = points.get(i - 1).y;
int x2 = points.get(i).x;
int y2 = points.get(i).y;
g2d.drawLine(x1, y1, x2, y2);
}
}
}
// Where the drawing happens
#Override
public void mousePressed(MouseEvent e) {
//status.setText("you pressed down the mouse");
if(!eraser){
xX1 = e.getX();
yY1 = e.getY();
points.add(e.getPoint());
}
}
#Override
public void mouseDragged(MouseEvent e) {
//status.setText("you draged the mouse");
Graphics2D g2d = bImage.createGraphics();
// this is the eraser code
if(eraser){
//Graphics2D g2d = bImage.createGraphics();
System.out.println("eraser = true");
System.out.println("Stroke = " + STROKESIZE);
g2d.setComposite(AlphaComposite.Clear);
g2d.setColor(new Color(0, 0, 0, 0));
g2d.drawRect(e.getX(), e.getY(), STROKESIZE, STROKESIZE);
g2d.fillRect(e.getX(), e.getY(), STROKESIZE, STROKESIZE);
// g2d.setColor(c);
imgLabel.repaint();
}else {
//g2d.setComposite();
points.add(e.getPoint());
System.out.println("point = " + e.getPoint());
imgLabel.repaint();
}
}
#Override
public void mouseReleased(MouseEvent e) {
//status.setText("you release the mouse click");
if(!eraser){
Graphics2D g2d = bImage.createGraphics();
g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2d.setColor(getColor()); // this is the final colour
g2d.setStroke(new BasicStroke(STROKESIZE));
if (points.size() >= 2) {
for (int i = 1; i < points.size(); i++) {
int x1 = points.get(i - 1).x;
int y1 = points.get(i - 1).y;
int x2 = points.get(i).x;
int y2 = points.get(i).y;
g2d.drawLine(x1, y1, x2, y2);
}
}
g2d.dispose();
points.clear();
imgLabel.repaint();
}
//imgLabel.repaint();
}
// End of where the drawing happens
public void clearDrawBoard() {
}
private Color getColor() {
return ColourToolbar.selectedColor;
}
private void setColor(Color col){
this.currentColor = col;
}
#Override
public void mouseClicked(MouseEvent e) {
//throw new UnsupportedOperationException("Not supported yet.");
}
}
BorderLayout can only have one component add to each of it a 5 positions. By adding the DrawPanel to the center position, you are effectively removing the TrackPanel.
Instead, set the layout manager of the TrackBar to BorderLayout and add the DrawPanel to it.
You could also use a JLayeredPane, but the management becomes more involved
I'm building an app that recognises lines drawn with mouse and creates music. I'm new to java2d so heres the problem i'm having:
When you draw, and then make another drawing, the last point of the previous drawing connects to the first of the new one. I havent been able to figure out how to fix this. Below is the code.
Another question is: I would like to store each stroke of drawing (from mousePressed to mouseReleased) into a ArrayList of type Shape, how can I go into that?
I'd like to be pointed in the right direction as I havent been able to find helpful info online. Thanks!
public class DrawBoard extends JPanel implements MouseListener,
MouseMotionListener {
public JLabel status;
public Point pstart, pfinish;
private Shape currentShape = null;
private ArrayList<Point> points = new ArrayList<Point>();
private ArrayList<Shape> lines = new ArrayList<Shape>();
public DrawBoard() {
Dimension size = getPreferredSize();
size.setSize(1024, 800); // w, h
setPreferredSize(size);
setOpaque(false);
status = new JLabel("default");
add(status, BorderLayout.SOUTH);
addMouseListener(this);
addMouseMotionListener(this);
}
#Override
public void mouseClicked(MouseEvent e) {
status.setText(String.format("Clicked at %d,%d", e.getX(), e.getY()));
}
// Where the drawing happens
#Override
public void mousePressed(MouseEvent e) {
status.setText("you pressed down the mouse");
this.pstart = e.getPoint();
}
#Override
public void mouseDragged(MouseEvent e) {
status.setText("you draged the mouse");
points.add(e.getPoint());
repaint();
}
#Override
public void mouseReleased(MouseEvent e) {
status.setText("you release the mouse click");
pfinish = e.getPoint();
}
// End of where the drawing happens
#Override
public void mouseEntered(MouseEvent e) {
status.setText("you entered the area");
}
#Override
public void mouseExited(MouseEvent e) {
status.setText("mouse exited the area");
}
#Override
public void mouseMoved(MouseEvent e) {
// throw new UnsupportedOperationException("Not supported yet.");
}
public void paint(Graphics g) {
super.paint(g);
Graphics2D g2 = (Graphics2D) g;
g2.setColor(Color.BLACK);
g2.setStroke(new BasicStroke(5));
for (int i = 0; i < points.size() - 2; i++) {
Point p1 = points.get(i);
Point p2 = points.get(i + 1);
g2.drawLine(p1.x, p1.y, p2.x, p2.y);
}
}
}
I have modified it using BufferedImage and it works for drawing normally, now the only thing does nto work is the clear method, i have tried different methods but none have worked. My new code is Below:
public class DrawBoard extends JPanel implements MouseListener, MouseMotionListener{
public JLabel status;
private JLabel imgLabel;
public Point pstart, pfinish;
private Shape currentShape = null;
private List<Point> points = new ArrayList<Point>();
private List<BufferedImage> lines = new ArrayList<BufferedImage>();
private static final int BI_WIDTH = 1024;
private static final int BI_HEIGHT = 800;
private BufferedImage bImage = new BufferedImage(BI_WIDTH, BI_HEIGHT,
BufferedImage.TYPE_INT_ARGB);
public DrawBoard(){
Graphics2D g2d = bImage.createGraphics();
g2d.dispose();
Dimension size = getPreferredSize();
size.setSize(1024,800); //w, h
setPreferredSize(size);
status = new JLabel("default");
add(status, BorderLayout.SOUTH);
addMouseListener(this);
addMouseMotionListener(this);
imgLabel = new JLabel(new ImageIcon(bImage)) {
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
paintInLabel(g);
}
};
imgLabel.setOpaque(false);
setOpaque(false);
add(imgLabel, BorderLayout.CENTER);
}
private void paintInLabel(Graphics g) {
Graphics2D g2d = (Graphics2D) g;
g2d.setColor(Color.BLUE); // this colour is when mouse is pressed
g2d.setStroke(new BasicStroke(5));
if (points.size() < 2) {
return;
}
for (int i = 1; i < points.size(); i++) {
int x1 = points.get(i - 1).x;
int y1 = points.get(i - 1).y;
int x2 = points.get(i).x;
int y2 = points.get(i).y;
g2d.drawLine(x1, y1, x2, y2);
}
}
#Override
public void mouseClicked(MouseEvent e) {
status.setText(String.format("Clicked at %d,%d", e.getX(), e.getY()));
}
// Where the drawing happens
#Override
public void mousePressed(MouseEvent e) {
status.setText("you pressed down the mouse");
this.pstart = e.getPoint();
points.add(e.getPoint());
}
#Override
public void mouseDragged(MouseEvent e) {
status.setText("you draged the mouse");
points.add(e.getPoint());
imgLabel.repaint();
}
#Override
public void mouseReleased(MouseEvent e) {
status.setText("you release the mouse click");
Graphics2D g2d = bImage.createGraphics();
g2d.setColor(Color.blue); // this is the final colour
g2d.setStroke(new BasicStroke(5));
if (points.size() >= 2) {
for (int i = 1; i < points.size(); i++) {
int x1 = points.get(i - 1).x;
int y1 = points.get(i - 1).y;
int x2 = points.get(i).x;
int y2 = points.get(i).y;
g2d.drawLine(x1, y1, x2, y2);
}
}
g2d.dispose();
points.clear();
imgLabel.repaint();
}
// End of where the drawing happens
#Override
public void mouseEntered(MouseEvent e) {
status.setText("you entered the area");
}
#Override
public void mouseExited(MouseEvent e) {
status.setText("mouse exited the area");
}
#Override
public void mouseMoved(MouseEvent e) {
//throw new UnsupportedOperationException("Not supported yet.");
}
public void clearDrawBoard() {
imgLabel.setIcon(null);
}
}
A few solutions and suggestions:
Don't draw from a single List<Point> as there's no way of knowing where one line ends and another begins.
Consider drawing each line to a BufferedImage once it is complete and display that BufferedImage in your JComponent in its paintComponent method. You would place it in the BufferedImage in the mouseReleased(...) method.
Or consider creating an List<List<Point>> so you can iterate through each line as needed. You would add the new List<Point> to the original List in the mouseReleased(...) method.
Consider using your List<Shape> and fill it with Line2D objects that can be drawn. The Line2D would be added to the List<Shape> in the mouseReleased(...) method.
Also: You should not override paint(...) but rather `paintComponent(...).
Also: Don't forget the #Override annotation for safer coding.
For example, please see my code and answer here.