In this short tutorial we are going to see how to monitor a very basic GUI event in Java Desktop Applications, which is mouse clicks. What we want to see is what button mouse the user pressed (left, middle or right click) and then we want to know the exact location, in coordinates, in our Frame that this event occurred.
In short, to handle mouse clicks in a Java AWT application :
- Create a
JFrame - Create a
MouseAdapterand add it to theJFrameusingaddMouseListenermethod. - Use
MouseEvent.getModifiers()andInputEventorMouseEventmasks to see what button of the mouse the user clicked. Alternatively you can useMouseEvent.getButton()method - Use
MouseEvent.getX()andMouseEvent.getY()to get the coordinates of the point that the user clicked into. - Alternatively you can use
MouseEvent.getPoint().xandMouseEvent.getPoint().yto get the coordinates. - Use
MouseEvent.getClickCountto get the amount of clicks that the user performed.
So, let’s see the code snippet bellow:
package com.javacodegeeks.snippets.desktop;
import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.Frame;
import java.awt.TextArea;
import java.awt.event.InputEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
public class MouseListener {
public static void main(String[] args) {
// Create frame with specific title
Frame frame = new Frame("Example Frame");
// Create a component to add to the frame; in this case a text area with sample text
Component textArea = new TextArea("Click here to see mouse click info...");
// Add a mouse listener to capture click events
textArea.addMouseListener(new MouseAdapter() {
public void mouseClicked(MouseEvent evt) {
TextArea source = (TextArea) evt.getSource();
if ((evt.getModifiers() & InputEvent.BUTTON1_MASK) != 0) {
source.setText(source.getText() + "nLeft mouse button clicked on point [" + evt.getPoint().x + "," + evt.getPoint().y + "]");
}
if ((evt.getModifiers() & InputEvent.BUTTON2_MASK) != 0) {
source.setText(source.getText() + "nCenter mouse button clicked on point [" + evt.getPoint().x + "," + evt.getPoint().y + "]");
}
if ((evt.getModifiers() & InputEvent.BUTTON3_MASK) != 0) {
source.setText(source.getText() + "nRight mouse button clicked on point [" + evt.getPoint().x + "," + evt.getPoint().y + "]");
}
}
});
// Add the components to the frame; by default, the frame has a border layout
frame.add(textArea, BorderLayout.NORTH);
// Show the frame
int width = 300;
int height = 300;
frame.setSize(width, height);
frame.setVisible(true);
}
}
This was an example on how to handle mouse clicks in Java.
