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POCursor disappears while calling repaint in mouseMoved?
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copied!<p>I have a problem with drawing horizontal and vertical lines from the cursor position while the cursor is moving. The cursor seem to disappear.</p> <p>I've attached a MouseInputAdapter to my swing component, which has a mouseMoved method which call repaint();</p> <p>Calling repaint will cause a paintComponent(Graphics g) to be called. In paintComponent i paint the horizontal and vertical line:</p> <pre><code>Dimension dim = getSize(); g2.setColor(Color.white); g2.fillRect(0, 0, dim.width, dim.height); g2.setColor(Color.black); Point pos = this.getMousePosition(); g2.draw(new Line2D.Double(0, pos.y, dim.getWidth(), pos.y)); g2.draw(new Line2D.Double(pos.x, 0, pos.x, dim.getHeight())); </code></pre> <p>Here is a screenshot:</p> <p><img src="https://i.stack.imgur.com/VCbSj.jpg" alt="enter image description here"></p> <p>The cursor should be in the white area that exists between the big horizontal line and the vertical one and should be at the left of the big number 1.2434307...</p> <p>When i move the cursor with my mouse i can see the cursor (crosshair) flickering which makes me believe my paint method is painting over the cursor.</p> <p>Anyone know where the problem may lie?</p> <p>As requested i've added a little test code.</p> <pre><code>public class TestApp extends JFrame { public TestApp() { super("TestApp"); this.getContentPane().setLayout(new BorderLayout()); this.getContentPane().add(new CustomComponent(), BorderLayout.CENTER); this.setSize(300, 300); this.setVisible(true); } class CustomComponent extends JComponent { public CustomComponent() { setCursor(Cursor.getPredefinedCursor(Cursor.CROSSHAIR_CURSOR)); MouseInputAdapter mia = new MouseInputAdapter() { @Override public void mouseMoved(MouseEvent e) { repaint(); } }; addMouseMotionListener(mia); addMouseListener(mia); } @Override public void paintComponent(Graphics g) { Dimension dim = getSize(); super.paintComponent(g); Graphics2D g2 = (Graphics2D) g; g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); g2.setColor(Color.white); g2.fillRect(0, 0, dim.width, dim.height); g2.setColor(Color.black); Point pos = this.getMousePosition(); if (pos != null) { g2.draw(new Line2D.Double(0, pos.y, dim.getWidth(), pos.y)); g2.draw(new Line2D.Double(pos.x, 0, pos.x, dim.getHeight())); g2.drawString("where is my cursor?", pos.x, pos.y); } } } public static void main(String[] args) { new TestApp(); } } </code></pre>

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