DBCaret.java

package com.drawbridge.text;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.Rectangle;

public class DBCaret
{

	private final DBDocument	mTextComponent;
	private boolean				mVisible;
	private Rectangle			mBounds;

	// Dot is the last drop position
	private Point				mDotPixelPosition;
	public Point				mDotCharPosition;

	// Mark is the initial click position
	public Point				mMarkPixelPosition;
	public Point				mMarkCharPosition;

	private Blinker				mBlinker;
	private Thread				mBlinkerThread;
	private int					mBlinkDelay		= 500;	// default is 600
	private final int			mCaretThickness	= 2;

	public DBCaret(DBDocument textComponent, Rectangle bounds) {
		mTextComponent = textComponent;
		mBounds = bounds;
		mVisible = false;
	}

	public void setDotPositionFromClick(int panelX, int panelY)
	{
		panelX = panelX - mTextComponent.getInsets().left;
		// get nearest valid line
		int closestYLine = mTextComponent.getLinePosition(panelY);
		Point closestCharPos = mTextComponent.getDocumentModel().getCharPosFromMouseClick(panelX, closestYLine);
		Point closestPixelPos = mTextComponent.charPosToPixelPos(closestCharPos.x, closestCharPos.y);
		setDotPosition(closestPixelPos, closestCharPos);
		restartDotAnimation();
	}

	public void setMarkPositionFromClick(int panelX, int panelY)
	{
		panelX = panelX - mTextComponent.getInsets().left;
		// get nearest valid line
		int closestYLine = mTextComponent.getLinePosition(panelY);
		Point closestCharPos = mTextComponent.getDocumentModel().getCharPosFromMouseClick(panelX, closestYLine);
		Point closestPixelPos = mTextComponent.charPosToPixelPos(closestCharPos.x, closestCharPos.y);
		setMarkPosition(closestPixelPos, closestCharPos);
		restartDotAnimation();
	}

	public Blinker getBlinker()
	{
		return mBlinker;
	}

	public void Paint(Graphics g)
	{
		if (mBlinker == null || mBlinkerThread == null) {
			mVisible = false;
			mBlinker = new Blinker();
			mBlinkerThread = new Thread(mBlinker);
			restartDotAnimation();
			DBCaret.this.setDotPosition(new Point(0, 0), new Point(0, 0));
		}

		// Draw Caret
		if (mVisible && mBounds != null && mDotPixelPosition != null)
		{

			int xPos = mBounds.x + mDotPixelPosition.x;
			int yPosTop = mBounds.y + mDotPixelPosition.y;
			int yPosBottom = yPosTop + mTextComponent.getLineHeight() + mTextComponent.getLineSpacing();

			Graphics2D g2 = (Graphics2D) g;
			g2.setColor(Color.black);
			g2.setStroke(new BasicStroke(mCaretThickness));

			g2.drawLine(xPos, yPosTop, xPos, yPosBottom);
		}
	}

	/**
	 * Controls the caret animation
	 */
	class Blinker implements Runnable
	{

		boolean	cancelled	= false;

		@Override
		public void run()
		{
			DBCaret.this.mVisible = false;
			do
			{
				try
				{
					DBCaret.this.mVisible = !DBCaret.this.mVisible;
					mTextComponent.repaint();
					Thread.sleep(DBCaret.this.mBlinkDelay);
				} catch (InterruptedException e)
				{
					e.printStackTrace();
				}
			} while (!cancelled && mTextComponent.hasFocus());
		}
	}

	public void restartDotAnimation()
	{
		if (mBlinkerThread != null && mBlinker != null && mBlinkerThread.isAlive())
		{
			mBlinker.cancelled = true;
		}
		mVisible = true;
		mBlinker = new Blinker();
		mBlinkerThread = new Thread(mBlinker);
		mBlinkerThread.start();
	}

	public void setBlinkRate(int blinkRateMilliseconds)
	{
		mBlinkDelay = blinkRateMilliseconds;
	}

	public void setVisible(boolean b)
	{
		mVisible = b;
	}

	public Point getDotPixelPosition()
	{
		return mDotPixelPosition;
	}

	public Point getDotCharPosition()
	{
		return mDotCharPosition;
	}

	public void setDotPosition(Point newPixelPosition, Point newCharPosition)
	{
		this.mDotPixelPosition = newPixelPosition;
		this.mDotCharPosition = newCharPosition;
	}

	public void setMarkPosition(Point newPixelPosition, Point newCharPosition)
	{
		this.mMarkPixelPosition = newPixelPosition;
		this.mMarkCharPosition = newCharPosition;
	}

	@Override
	public String toString()
	{
		return "DBCaret Position: (" + mDotPixelPosition.x + ", " + mDotPixelPosition.y + ")";
	}

	public void setDotCharPosition(Point charPos)
	{
		mDotCharPosition = charPos;
		mDotPixelPosition = mTextComponent.charPosToPixelPos(charPos.x, charPos.y);
		this.restartDotAnimation();
	}

	public void setMarkCharPosition(Point charPos)
	{
		mMarkCharPosition = charPos;
		mMarkPixelPosition = mTextComponent.charPosToPixelPos(charPos.x, charPos.y);
		this.restartDotAnimation();
	}

	public Point getMarkCharPosition()
	{
		return mMarkCharPosition;
	}

	public Point getMarkPixelPosition()
	{
		return mMarkPixelPosition;
	}

	public String toStringMarkChar()
	{
		return "(" + this.mMarkCharPosition.x + ", " + this.mMarkCharPosition.y + ")";
	}

	public String toStringDotChar()
	{
		return "(" + this.mDotCharPosition.x + ", " + this.mDotCharPosition.y + ")";
	}

}