Moving image with mouse Java

Question

Okay I am fairly new to Java and am having problems on a project that was assigned to me. I am having trouble moving my CTetrimino object across the JFrame Here is my CTetrimino class.

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Image;

public class CTetriMino {

public CTetriMino(int type, int x, int y, int w, int h, Color c) 
{
    CMino m = new CMino();
    d = m.getDiameter();
    Type=type;
    X=x;
    Y=y;
    Width=w;
    Height=h;
    FillColor=c;
}

public CTetriMino(CTetriMino src) { // copy constructor
    Type=src.Type;
    X=src.X;
    Y=src.Y;
    Width=src.Width;
    Height=src.Height;
    FillColor=src.FillColor;
}

public int getX() { return X; }
public void setX(int x) { X=x; }
public int getY() { return Y; }
public void setY(int y) { Y=y; }

public void draw(Graphics g) {
    g.setColor(FillColor);
    switch (Type) {
    case 0:
        //g.fillOval(X, Y, Width, Height);
        //break;
        g.fillOval(X, Y, d, d);
        g.fillOval(X+d,Y, d, d);
        g.fillOval(X+d,Y-d, d, d);
        g.fillOval(X+d+d,Y-d, d, d);
        break;
    case 1:
        g.fillRect(X, Y, Width, Height);
        //g.fillOval(X, Y, d, d);
        //g.fillOval(X+d,Y, d, d);
        //g.fillOval(X+d,Y+d, d, d);
        //g.fillOval(X+d+d,Y+d, d, d);
        break;
    case 2:
        g.fillOval(X, Y, d, d);
        g.fillOval(X+d,Y, d, d);
        g.fillOval(X,Y-d, d, d);
        g.fillOval(X+d,Y-d, d, d);
        break;
    case 3:
        g.fillOval(X, Y, d, d);
        g.fillOval(X,Y+d, d, d);
        g.fillOval(X,Y+d+d, d, d);
        g.fillOval(X,Y-d, d, d);
        break;
    case 4:
        g.fillOval(X, Y, d, d);
        g.fillOval(X,Y+d, d, d);
        g.fillOval(X,Y-d, d, d);
        g.fillOval(X+d,Y-d, d, d);
        break;
    case 5:
        g.fillOval(X, Y, d, d);
        g.fillOval(X,Y+d, d, d);
        g.fillOval(X,Y-d, d, d);
        g.fillOval(X-d,Y-d, d, d);
        break;
    case 6:
        g.fillOval(X, Y, d, d);
        g.fillOval(X+d,Y, d, d);
        g.fillOval(X,Y-d, d, d);
        g.fillOval(X-d,Y, d, d);
        break;
        }
    }

public boolean containPoint(int x, int y) {
        switch (Type) {
        case 0:
            {
                double a=Width/2.0;
                double b=Height/2.0;
                double xc=X+a;
                double yc=Y+b;
                System.out.println(a);
                System.out.println(b);
                System.out.println(xc);
                System.out.println(yc);
                System.out.println(((x-xc)*(x-xc)/(a*a)+(y-yc)*(y-yc)/(b*b)<=1.0));
                return ((x-xc)*(x-xc)/(a*a)+(y-yc)*(y-yc)/(b*b)<=1.0);

            }
        case 1:
            return (x>=X && y>=Y && x<X+Width && y<Y+Height);

        }

        return false;
    }





private int Type;   
private int X;
private int Y;
private int Width;
private int Height;
private Color FillColor;
private int d;
}

Here is my Panel class which I add to the Jframe in a TestNewTetris class.

import java.awt.Color;
import java.awt.Image;
import java.awt.Graphics;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;

import javax.swing.*;

import java.util.*;



public class Panel extends JPanel 
implements MouseListener, MouseMotionListener
{


private ArrayList<CTetriMino> originals;  
private ArrayList<CTetriMino> duplicates;

private CTetriMino BlockToBeMoved;
private int m_nOffsetX; // difference between cursor and top-left corner
private int m_nOffsetY;

// double buffering
private Image backBuffer;
private Graphics gBackBuffer;

boolean isInitialized;

// init and register mouse event handler
public Panel()
{
    isInitialized=false;
    // handle mouse and mouse motion events
    this.addMouseListener(this);
    this.addMouseMotionListener(this);
}

// Set up the initial state after the panel is created
void init()
{
    // Initial state
    duplicates = new ArrayList<CTetriMino>();
    originals = new ArrayList<CTetriMino>();
    Color[] colors = {Color.red, Color.green, Color.blue, Color.magenta, Color.cyan, Color.yellow, Color.orange};
    int count=colors.length;
    int dx=10;
    int dy=30;
    int gap=20;
    int length=(getSize().height-2*dy-(count-1)*gap)/count;
    for (int i=0; i<count; i++) { 
        //originals.add(new CTetriMino((i<count/2)?0:1, dx, dy+i*(length+gap), length, length, colors[i]));
        System.out.println(length);
        originals.add(new CTetriMino(i, dx, dy, length, length, colors[i])); 
        dx = dx+110;

    }
    BlockToBeMoved=null; // no shape selected

    // create the back buffer
    backBuffer = createImage(getSize().width, getSize().height);
    gBackBuffer = backBuffer.getGraphics();
}

// State Presentation
public void paintComponent( Graphics g )
{
    // super.paintComponent( g ); // clears drawing area

    if (!isInitialized) {
        isInitialized=true;
        init();
    }
    // State Presentation, using double buffers
    // First, clear the back buffer
    gBackBuffer.setColor(Color.white);
    gBackBuffer.clearRect(0, 0, getSize().width, getSize().height);
    // draw the originals to back buffer
    for (int i=0; i<originals.size(); i++) {
        originals.get(i).draw(gBackBuffer);
    }
    // draw the duplicates to back buffer
    for (int i=0; i<duplicates.size(); i++) {
        duplicates.get(i).draw(gBackBuffer);
    }
    // copy from back buffer to front
    g.drawImage(backBuffer, 0, 0, null);
    g.fillRect(0, 100, 800, 4);
    g.fillRect(0, 400, 800, 4);
} // end method paintComponent

// MouseListener event handlers
public void mouseClicked( MouseEvent e )
{
    if (e.isMetaDown()) {   // right button
        for (int i=duplicates.size()-1; i>=0; i--) {
            if (duplicates.get(i).containPoint(e.getX(), e.getY())) {
                duplicates.remove(i);
                repaint();
                break;
            }
        }
    }
}

public void mousePressed( MouseEvent e )
{
    if (e.isMetaDown()) return; // ignore right button

    // First, check the originals, from top down (i.e. back to front)
    for (int i=duplicates.size()-1; i>=0; i--) {
        CTetriMino p=duplicates.get(i);
        if (p.containPoint(e.getX(), e.getY())) {
            duplicates.remove(i);
            duplicates.add(p);  // move to the end, i.e. the top
            BlockToBeMoved=p;
            m_nOffsetX=e.getX()-BlockToBeMoved.getX();
            m_nOffsetY=e.getY()-BlockToBeMoved.getY();
            repaint();
            return;
        }
    }
    // Second, check the orginals 
    for (int i=originals.size()-1; i>=0; i--) {
        CTetriMino p=originals.get(i);
        System.out.println(p.containPoint(e.getX(), e.getY()));
        if (p.containPoint(e.getX(), e.getY())) {
            CTetriMino p2=new CTetriMino(p); // make a copy of p
            duplicates.add(p2); // add to the end
            BlockToBeMoved=p2;  // p2 is selected, to be moved
            m_nOffsetX=e.getX()-BlockToBeMoved.getX();
            m_nOffsetY=e.getY()-BlockToBeMoved.getY();
            repaint();
            return;
        }
    }
}

public void mouseReleased( MouseEvent e )
{
    BlockToBeMoved=null; // no shape selected
}

public void mouseEntered( MouseEvent e )
{
}

public void mouseExited( MouseEvent e )
{
}

public void mouseMoved( MouseEvent e )
{
}

public void mouseDragged( MouseEvent e )
{
    if (e.isMetaDown()) return; // ignore right button
    System.out.println(BlockToBeMoved);
    if (BlockToBeMoved!=null) {
        BlockToBeMoved.setX(e.getX()-m_nOffsetX);
        BlockToBeMoved.setY(e.getY()-m_nOffsetY);
        repaint();
    }

} // end method mouseDragged






}

I would show what my program does when I run it but I do not have a high enough reputation yet.

The bottom Jframe is what is compiled if I change this code:

case 0:
g.fillOval(X, Y, d, d);
g.fillOval(X+d,Y, d, d);
g.fillOval(X+d,Y-d, d, d);
g.fillOval(X+d+d,Y-d, d, d);
break;

to this:

case 0:
g.fillOval(X, Y, Width, Height);
break;

In both variants I am able to drag the green square. In the second variant I am able to drag the red circle. I CAN'T however move my red tetrimino. I am simply wondering why I cannot move my red tetrimino. Eventually I want to be able to move all of the tetriminos and drag them under the second black line to delete them. I also want to be able to rotate the tetriminos by pressing righr click. Any code or advice is appreciated. If you need more information I will provide it asap. Thanks.

Answer 1

If I understood you correctly the solution should be like this below. Please create image package like below.You need to two events for label mouse dragged , label mouse pressed to do that. Add icon to label it should be image your image.

critical imports

    import java.awt.Point;

events

   private void jLabel1MousePressed(java.awt.event.MouseEvent evt) {                                     
          initialClick = evt.getPoint();
    }  





     private void jLabel1MouseDragged(java.awt.event.MouseEvent evt) {                                     

        int thisX = jLabel1.getLocation().x;
        int thisY = jLabel1.getLocation().y;

        // Determine how much the mouse moved since the initial click
        int xMoved = (thisX + evt.getX()) - (thisX + initialClick.x);
        int yMoved = (thisY + evt.getY()) - (thisY + initialClick.y);

        // Move picture to this position
        int X = thisX + xMoved;
        int Y = thisY + yMoved;

        jLabel1.setLocation(X, Y);
        jLabel1.repaint();


    }