ImageCanvas (ImageJ API)

java.lang.Object
- java.awt.Component
- - java.awt.Canvas
  - - ij.gui.ImageCanvas

All Implemented Interfaces:

MouseListener, MouseMotionListener, ImageObserver, MenuContainer, Serializable, Cloneable, EventListener, Accessible

Direct Known Subclasses:

PlotCanvas
```
public class ImageCanvas
extends Canvas
implements MouseListener, MouseMotionListener, Cloneable
```
This is a Canvas used to display images in a Window.

See Also:

Serialized Form

Nested Class Summary
- Nested classes/interfaces inherited from class java.awt.Canvas
  Canvas.AccessibleAWTCanvas
- Nested classes/interfaces inherited from class java.awt.Component
  Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy

Field Summary

Fields
Modifier and Type	Field	Description
`protected static Cursor`	`crosshairCursor`
`protected static Cursor`	`defaultCursor`
`protected int`	`dstHeight`
`protected int`	`dstWidth`
`protected int`	`flags`
`protected static Cursor`	`handCursor`
`protected ImageJ`	`ij`
`protected int`	`imageHeight`
`protected boolean`	`imageUpdated`
`protected int`	`imageWidth`
`protected ImagePlus`	`imp`
`protected int`	`lastZoomSX`	Screen coordinates where the last zoom operation was done (initialized to impossible value)
`protected int`	`lastZoomSY`
`protected double`	`magnification`
`protected static int`	`MAX_MOUSEMOVE_ZOOM`	If the mouse moves less than this in screen pixels, successive zoom operations are on the same image pixel
`protected static Cursor`	`moveCursor`
`protected Rectangle`	`srcRect`
`static boolean`	`usePointer`
`protected int`	`xMouse`
`protected int`	`xMouseStart`
`protected int`	`xSrcStart`
`protected int`	`yMouse`
`protected int`	`yMouseStart`
`protected int`	`ySrcStart`
`protected int`	`zoomTargetOX`	Image (=offscreen) coordinates where the cursor was moved to for zooming
`protected int`	`zoomTargetOY`

Fields inherited from class java.awt.Component
accessibleContext, BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Fields inherited from interface java.awt.image.ImageObserver
ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH

Constructor Summary

Constructors
Constructor Description

ImageCanvas(ImagePlus imp)

Constructors
Constructor	Description
`ImageCanvas(ImagePlus imp)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method	Description
`protected Dimension`	`canEnlarge(int newWidth, int newHeight)`	Returns the size to which the window can be enlarged, or null if it can't be enlarged.
`boolean`	`cursorOverImage()`	Returns 'true' if the cursor is over this image.
`void`	`disablePopupMenu(boolean status)`	Disable/enable popup menu.
`void`	`fitToWindow()`
`Point`	`getCursorLoc()`	Returns the current cursor location in image coordinates.
`boolean`	`getCustomRoi()`
`Vector`	`getDisplayList()`	Deprecated. replaced by ImagePlus.getOverlay()
`static double`	`getHigherZoomLevel(double currentMag)`
`ImagePlus`	`getImage()`	Returns the ImagePlus object that is associated with this ImageCanvas.
`static double`	`getLowerZoomLevel(double currentMag)`
`double`	`getMagnification()`
`int`	`getModifiers()`	Returns the mouse event modifiers.
`Overlay`	`getOverlay()`	Use ImagePlus.getOverlay().
`boolean`	`getPaintPending()`
`Dimension`	`getPreferredSize()`
`boolean`	`getScaleToFit()`
`static Color`	`getShowAllColor()`	Obsolete
`Overlay`	`getShowAllList()`
`boolean`	`getShowAllROIs()`	Obsolete
`int`	`getSliceNumber(String label)`
`Rectangle`	`getSrcRect()`
`protected void`	`handlePopupMenu(MouseEvent e)`
`protected void`	`handleRoiMouseDown(MouseEvent e)`
`boolean`	`hideZoomIndicator(boolean hide)`
`void`	`mouseClicked(MouseEvent e)`
`void`	`mouseDragged(MouseEvent e)`
`void`	`mouseEntered(MouseEvent e)`
`void`	`mouseExited(MouseEvent e)`
`void`	`mouseMoved(MouseEvent e)`
`void`	`mousePressed(MouseEvent e)`
`void`	`mouseReleased(MouseEvent e)`
`int`	`offScreenX(int sx)`	Converts a screen x-coordinate to an offscreen x-coordinate.
`double`	`offScreenXD(int sx)`	Converts a screen x-coordinate to a floating-point offscreen x-coordinate.
`int`	`offScreenY(int sy)`	Converts a screen y-coordinate to an offscreen y-coordinate.
`double`	`offScreenYD(int sy)`	Converts a screen y-coordinate to a floating-point offscreen y-coordinate.
`void`	`paint(Graphics g)`
`void`	`resetDoubleBuffer()`
`boolean`	`roiManagerSelect(Roi roi, boolean delete)`
`int`	`screenX(int ox)`	Converts an offscreen x-coordinate to a screen x-coordinate.
`int`	`screenXD(double ox)`	Converts a floating-point offscreen x-coordinate to a screen x-coordinate.
`int`	`screenY(int oy)`	Converts an offscreen y-coordinate to a screen y-coordinate.
`int`	`screenYD(double oy)`	Converts a floating-point offscreen x-coordinate to a screen x-coordinate.
`protected void`	`scroll(int sx, int sy)`
`void`	`setCursor(int sx, int sy, int ox, int oy)`	Sets the cursor based on the current tool and cursor location.
`static void`	`setCursor(Cursor cursor, int type)`	Experimental
`void`	`setCustomRoi(boolean customRoi)`	Allows plugins (e.g., Orthogonal_Views) to create a custom ROI using a display list.
`void`	`setDisplayList(Roi roi, Color color)`	Deprecated. replaced by ImagePlus.setOverlay(Roi, Color, int, Color)
`void`	`setDisplayList(Shape shape, Color color, BasicStroke stroke)`	Deprecated. replaced by ImagePlus.setOverlay(Shape, Color, BasicStroke)
`void`	`setDisplayList(Vector list)`	Deprecated. replaced by ImagePlus.setOverlay(ij.gui.Overlay)
`void`	`setDrawingColor(int ox, int oy, boolean setBackground)`	Sets the foreground drawing color (or background color if 'setBackground' is true) to the color of the pixel at (ox,oy).
`void`	`setDrawingSize(int width, int height)`	Obsolete; replaced by setSize()
`void`	`setImageUpdated()`	ImagePlus.updateAndDraw calls this method to force the paint() method to update the image from the ImageProcessor.
`void`	`setMagnification(double magnification)`
`void`	`setOverlay(Overlay overlay)`	Use ImagePlus.setOverlay(ij.gui.Overlay).
`void`	`setPaintPending(boolean state)`
`void`	`setScaleToFit(boolean scaleToFit)`
`static void`	`setShowAllColor(Color c)`	Obsolete
`void`	`setShowAllList(Overlay showAllList)`
`void`	`setShowAllROIs(boolean showAllROIs)`	Obsolete
`void`	`setShowCursorStatus(boolean status)`	Called by IJ.showStatus() to prevent status bar text from being overwritten until the cursor moves at least 12 pixels.
`void`	`setSize(int width, int height)`
`void`	`setSourceRect(Rectangle r)`	Sets the region of the image (in pixels) to be displayed.
`protected void`	`setupScroll(int ox, int oy)`
`void`	`unzoom()`	Implements the Image/Zoom/Original Scale command.
`void`	`update(Graphics g)`
`void`	`zoom100Percent()`	Implements the Image/Zoom/View 100% command.
`void`	`zoomIn(int sx, int sy)`	Zooms in by making the window bigger.
`void`	`zoomOut(int sx, int sy)`	Zooms out by making the source rectangle (srcRect) larger and centering it on (x,y).

Methods inherited from class java.awt.Canvas
addNotify, createBufferStrategy, createBufferStrategy, getAccessibleContext, getBufferStrategy

Methods inherited from class java.awt.Component
action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, bounds, checkImage, checkImage, coalesceEvents, contains, contains, createImage, createImage, createVolatileImage, createVolatileImage, deliverEvent, disable, disableEvents, dispatchEvent, doLayout, enable, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getAlignmentX, getAlignmentY, getBackground, getBaseline, getBaselineResizeBehavior, getBounds, getBounds, getColorModel, getComponentAt, getComponentAt, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeys, getFocusTraversalKeysEnabled, getFont, getFontMetrics, getForeground, getGraphics, getGraphicsConfiguration, getHeight, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getListeners, getLocale, getLocation, getLocation, getLocationOnScreen, getMaximumSize, getMinimumSize, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getSize, getToolkit, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, hide, imageUpdate, inside, invalidate, isBackgroundSet, isCursorSet, isDisplayable, isDoubleBuffered, isEnabled, isFocusable, isFocusCycleRoot, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isOpaque, isPreferredSizeSet, isShowing, isValid, isVisible, keyDown, keyUp, layout, list, list, list, list, list, locate, location, lostFocus, minimumSize, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, paramString, postEvent, preferredSize, prepareImage, prepareImage, print, printAll, processComponentEvent, processEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processKeyEvent, processMouseEvent, processMouseMotionEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removeNotify, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, requestFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, requestFocusInWindow, reshape, resize, resize, revalidate, setBackground, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setEnabled, setFocusable, setFocusTraversalKeys, setFocusTraversalKeysEnabled, setFont, setForeground, setIgnoreRepaint, setLocale, setLocation, setLocation, setMaximumSize, setMinimumSize, setMixingCutoutShape, setName, setPreferredSize, setSize, setVisible, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle, validate

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - defaultCursor
```
protected static Cursor defaultCursor
```
  - handCursor
```
protected static Cursor handCursor
```
  - moveCursor
```
protected static Cursor moveCursor
```
  - crosshairCursor
```
protected static Cursor crosshairCursor
```
  - usePointer
```
public static boolean usePointer
```
  - imp
```
protected ImagePlus imp
```
  - imageUpdated
```
protected boolean imageUpdated
```
  - srcRect
```
protected Rectangle srcRect
```
  - imageWidth
```
protected int imageWidth
```
  - imageHeight
```
protected int imageHeight
```
  - xMouse
```
protected int xMouse
```
  - yMouse
```
protected int yMouse
```
  - MAX_MOUSEMOVE_ZOOM
```
protected static final int MAX_MOUSEMOVE_ZOOM
```
    If the mouse moves less than this in screen pixels, successive zoom operations are on the same image pixel
    
    See Also:
    
    Constant Field Values
  - lastZoomSX
```
protected int lastZoomSX
```
    Screen coordinates where the last zoom operation was done (initialized to impossible value)
  - lastZoomSY
```
protected int lastZoomSY
```
  - zoomTargetOX
```
protected int zoomTargetOX
```
    Image (=offscreen) coordinates where the cursor was moved to for zooming
  - zoomTargetOY
```
protected int zoomTargetOY
```
  - ij
```
protected ImageJ ij
```
  - magnification
```
protected double magnification
```
  - dstWidth
```
protected int dstWidth
```
  - dstHeight
```
protected int dstHeight
```
  - xMouseStart
```
protected int xMouseStart
```
  - yMouseStart
```
protected int yMouseStart
```
  - xSrcStart
```
protected int xSrcStart
```
  - ySrcStart
```
protected int ySrcStart
```
  - flags
```
protected int flags
```
- Constructor Detail
  - ImageCanvas
```
public ImageCanvas(ImagePlus imp)
```
- Method Detail
  - setSourceRect
```
public void setSourceRect(Rectangle r)
```
    Sets the region of the image (in pixels) to be displayed.
  - getSrcRect
```
public Rectangle getSrcRect()
```
  - setDrawingSize
```
public void setDrawingSize(int width,
                           int height)
```
    Obsolete; replaced by setSize()
  - setSize
```
public void setSize(int width,
                    int height)
```
    Overrides:
    
    setSize in class Component
  - setImageUpdated
```
public void setImageUpdated()
```
    ImagePlus.updateAndDraw calls this method to force the paint() method to update the image from the ImageProcessor.
  - setPaintPending
```
public void setPaintPending(boolean state)
```
  - getPaintPending
```
public boolean getPaintPending()
```
  - update
```
public void update(Graphics g)
```
    Overrides:
    
    update in class Canvas
  - paint
```
public void paint(Graphics g)
```
    Overrides:
    
    paint in class Canvas
  - getSliceNumber
```
public int getSliceNumber(String label)
```
  - resetDoubleBuffer
```
public void resetDoubleBuffer()
```
  - getPreferredSize
```
public Dimension getPreferredSize()
```
    Overrides:
    
    getPreferredSize in class Component
  - getCursorLoc
```
public Point getCursorLoc()
```
    Returns the current cursor location in image coordinates.
  - cursorOverImage
```
public boolean cursorOverImage()
```
    Returns 'true' if the cursor is over this image.
  - getModifiers
```
public int getModifiers()
```
    Returns the mouse event modifiers.
  - getImage
```
public ImagePlus getImage()
```
    Returns the ImagePlus object that is associated with this ImageCanvas.
  - setCursor
```
public void setCursor(int sx,
                      int sy,
                      int ox,
                      int oy)
```
    Sets the cursor based on the current tool and cursor location.
  - offScreenX
```
public int offScreenX(int sx)
```
    Converts a screen x-coordinate to an offscreen x-coordinate.
  - offScreenY
```
public int offScreenY(int sy)
```
    Converts a screen y-coordinate to an offscreen y-coordinate.
  - offScreenXD
```
public double offScreenXD(int sx)
```
    Converts a screen x-coordinate to a floating-point offscreen x-coordinate.
  - offScreenYD
```
public double offScreenYD(int sy)
```
    Converts a screen y-coordinate to a floating-point offscreen y-coordinate.
  - screenX
```
public int screenX(int ox)
```
    Converts an offscreen x-coordinate to a screen x-coordinate.
  - screenY
```
public int screenY(int oy)
```
    Converts an offscreen y-coordinate to a screen y-coordinate.
  - screenXD
```
public int screenXD(double ox)
```
    Converts a floating-point offscreen x-coordinate to a screen x-coordinate.
  - screenYD
```
public int screenYD(double oy)
```
    Converts a floating-point offscreen x-coordinate to a screen x-coordinate.
  - getMagnification
```
public double getMagnification()
```
  - setMagnification
```
public void setMagnification(double magnification)
```
  - fitToWindow
```
public void fitToWindow()
```
  - getLowerZoomLevel
```
public static double getLowerZoomLevel(double currentMag)
```
  - getHigherZoomLevel
```
public static double getHigherZoomLevel(double currentMag)
```
  - zoomIn
```
public void zoomIn(int sx,
                   int sy)
```
    Zooms in by making the window bigger. If it can't be made bigger, then makes the source rectangle (srcRect) smaller and centers it on the position in the image where the cursor was when zooming has started. Note that sx and sy are screen coordinates.
  - canEnlarge
```
protected Dimension canEnlarge(int newWidth,
                               int newHeight)
```
    Returns the size to which the window can be enlarged, or null if it can't be enlarged. newWidth, newHeight is the size needed for showing the full image at the magnification needed
  - zoomOut
```
public void zoomOut(int sx,
                    int sy)
```
    Zooms out by making the source rectangle (srcRect) larger and centering it on (x,y). If we can't make it larger, then make the window smaller. Note that sx and sy are screen coordinates.
  - unzoom
```
public void unzoom()
```
    Implements the Image/Zoom/Original Scale command.
  - zoom100Percent
```
public void zoom100Percent()
```
    Implements the Image/Zoom/View 100% command.
  - scroll
```
protected void scroll(int sx,
                      int sy)
```
  - setDrawingColor
```
public void setDrawingColor(int ox,
                            int oy,
                            boolean setBackground)
```
    Sets the foreground drawing color (or background color if 'setBackground' is true) to the color of the pixel at (ox,oy).
  - mousePressed
```
public void mousePressed(MouseEvent e)
```
    Specified by:
    
    mousePressed in interface MouseListener
  - setupScroll
```
protected void setupScroll(int ox,
                           int oy)
```
  - handlePopupMenu
```
protected void handlePopupMenu(MouseEvent e)
```
  - mouseExited
```
public void mouseExited(MouseEvent e)
```
    Specified by:
    
    mouseExited in interface MouseListener
  - mouseDragged
```
public void mouseDragged(MouseEvent e)
```
    Specified by:
    
    mouseDragged in interface MouseMotionListener
  - handleRoiMouseDown
```
protected void handleRoiMouseDown(MouseEvent e)
```
  - disablePopupMenu
```
public void disablePopupMenu(boolean status)
```
    Disable/enable popup menu.
  - setShowAllList
```
public void setShowAllList(Overlay showAllList)
```
  - getShowAllList
```
public Overlay getShowAllList()
```
  - setShowAllROIs
```
public void setShowAllROIs(boolean showAllROIs)
```
    Obsolete
  - getShowAllROIs
```
public boolean getShowAllROIs()
```
    Obsolete
  - getShowAllColor
```
public static Color getShowAllColor()
```
    Obsolete
  - setShowAllColor
```
public static void setShowAllColor(Color c)
```
    Obsolete
  - setCursor
```
public static void setCursor(Cursor cursor,
                             int type)
```
    Experimental
  - setOverlay
```
public void setOverlay(Overlay overlay)
```
    Use ImagePlus.setOverlay(ij.gui.Overlay).
  - getOverlay
```
public Overlay getOverlay()
```
    Use ImagePlus.getOverlay().
  - setDisplayList
```
public void setDisplayList(Vector list)
```
    Deprecated.
    replaced by ImagePlus.setOverlay(ij.gui.Overlay)
  - setDisplayList
```
public void setDisplayList(Shape shape,
                           Color color,
                           BasicStroke stroke)
```
    Deprecated.
    replaced by ImagePlus.setOverlay(Shape, Color, BasicStroke)
  - setDisplayList
```
public void setDisplayList(Roi roi,
                           Color color)
```
    Deprecated.
    replaced by ImagePlus.setOverlay(Roi, Color, int, Color)
  - getDisplayList
```
public Vector getDisplayList()
```
    Deprecated.
    replaced by ImagePlus.getOverlay()
  - setCustomRoi
```
public void setCustomRoi(boolean customRoi)
```
    Allows plugins (e.g., Orthogonal_Views) to create a custom ROI using a display list.
  - getCustomRoi
```
public boolean getCustomRoi()
```
  - setShowCursorStatus
```
public void setShowCursorStatus(boolean status)
```
    Called by IJ.showStatus() to prevent status bar text from being overwritten until the cursor moves at least 12 pixels.
  - mouseReleased
```
public void mouseReleased(MouseEvent e)
```
    Specified by:
    
    mouseReleased in interface MouseListener
  - roiManagerSelect
```
public boolean roiManagerSelect(Roi roi,
                                boolean delete)
```
  - mouseMoved
```
public void mouseMoved(MouseEvent e)
```
    Specified by:
    
    mouseMoved in interface MouseMotionListener
  - mouseEntered
```
public void mouseEntered(MouseEvent e)
```
    Specified by:
    
    mouseEntered in interface MouseListener
  - mouseClicked
```
public void mouseClicked(MouseEvent e)
```
    Specified by:
    
    mouseClicked in interface MouseListener
  - setScaleToFit
```
public void setScaleToFit(boolean scaleToFit)
```
  - getScaleToFit
```
public boolean getScaleToFit()
```
  - hideZoomIndicator
```
public boolean hideZoomIndicator(boolean hide)
```

Class ImageCanvas

Nested Class Summary

Nested classes/interfaces inherited from class java.awt.Canvas

Nested classes/interfaces inherited from class java.awt.Component

Field Summary

Fields inherited from class java.awt.Component

Fields inherited from interface java.awt.image.ImageObserver

Constructor Summary

Method Summary

Methods inherited from class java.awt.Canvas

Methods inherited from class java.awt.Component

Methods inherited from class java.lang.Object

Field Detail

defaultCursor

handCursor

moveCursor

crosshairCursor

usePointer

imp

imageUpdated

srcRect

imageWidth

imageHeight

xMouse

yMouse

MAX_MOUSEMOVE_ZOOM

lastZoomSX

lastZoomSY

zoomTargetOX

zoomTargetOY

ij

magnification

dstWidth

dstHeight

xMouseStart

yMouseStart

xSrcStart

ySrcStart

flags

Constructor Detail

ImageCanvas

Method Detail

setSourceRect

getSrcRect

setDrawingSize

setSize

setImageUpdated

setPaintPending

getPaintPending

update

paint

getSliceNumber

resetDoubleBuffer

getPreferredSize

getCursorLoc

cursorOverImage

getModifiers

getImage

setCursor

offScreenX

offScreenY

offScreenXD

offScreenYD

screenX

screenY

screenXD

screenYD

getMagnification

setMagnification

fitToWindow

getLowerZoomLevel

getHigherZoomLevel

zoomIn

canEnlarge

zoomOut

unzoom

zoom100Percent

scroll

setDrawingColor

mousePressed