Package org.eclipse.jface.text

Class AbstractInformationControlManager

java.lang.Object
org.eclipse.jface.text.AbstractInformationControlManager
Direct Known Subclasses:
AbstractHoverInformationControlManager, InformationPresenter
public abstract class AbstractInformationControlManager extends Object
Manages the life cycle, visibility, layout, and contents of an IInformationControl. This manager can be installed on and removed from a control, referred to as the subject control, i.e. the one from which the subject of the information to be shown is retrieved. Also a manager can be enabled or disabled. An installed and enabled manager can be forced to show information in its information control using showInformation. An information control manager uses an IInformationControlCloser to define the behavior when a presented information control must be closed. The disposal of the subject and the information control are internally handled by the information control manager and are not the responsibility of the information control closer.
Since:
2.0
See Also:

  • Field Details

    • ANCHOR_TOP

      public static final AbstractInformationControlManager.Anchor ANCHOR_TOP
      Anchor representing the top of the information area

    • ANCHOR_BOTTOM

      public static final AbstractInformationControlManager.Anchor ANCHOR_BOTTOM
      Anchor representing the bottom of the information area

    • ANCHOR_LEFT

      public static final AbstractInformationControlManager.Anchor ANCHOR_LEFT
      Anchor representing the left side of the information area

    • ANCHOR_RIGHT

      public static final AbstractInformationControlManager.Anchor ANCHOR_RIGHT
      Anchor representing the right side of the information area

    • ANCHOR_GLOBAL

      public static final AbstractInformationControlManager.Anchor ANCHOR_GLOBAL
      Anchor representing the middle of the subject control
      Since:
      2.1

    • STORE_LOCATION_X

      public static final String STORE_LOCATION_X
      Dialog store constant for the location's x-coordinate.
      Since:
      3.0
      See Also:

    • STORE_LOCATION_Y

      public static final String STORE_LOCATION_Y
      Dialog store constant for the location's y-coordinate.
      Since:
      3.0
      See Also:

    • STORE_SIZE_WIDTH

      public static final String STORE_SIZE_WIDTH
      Dialog store constant for the size's width.
      Since:
      3.0
      See Also:

    • STORE_SIZE_HEIGHT

      public static final String STORE_SIZE_HEIGHT
      Dialog store constant for the size's height.
      Since:
      3.0
      See Also:

    • DEBUG

      protected static final boolean DEBUG
      Tells whether this class and its subclasses are in debug mode.

      Subclasses may use this.

      Since:
      3.4

    • fInformationControl

      protected IInformationControl fInformationControl
      The information control.

      This field should not be referenced by subclasses. It is protected for API compatibility reasons.

    • fInformationControlCreator

      protected IInformationControlCreator fInformationControlCreator
      The information control creator.

      This field should not be referenced by subclasses. It is protected for API compatibility reasons.

    • fInformationControlCloser

      protected AbstractInformationControlManager.IInformationControlCloser fInformationControlCloser
      The information control closer.

      This field should not be referenced by subclasses. It is protected for API compatibility reasons.

    • fDisposed

      protected boolean fDisposed
      Indicates that the information control has been disposed.

      This field should not be referenced by subclasses. It is protected for API compatibility reasons.

  • Constructor Details

    • AbstractInformationControlManager

      protected AbstractInformationControlManager(IInformationControlCreator creator)
      Creates a new information control manager using the given information control creator. By default the following configuration is given:
      • enabled == false
      • horizontal margin == 5 points
      • vertical margin == 5 points
      • width constraint == 60 characters
      • height constraint == 6 characters
      • enforce constraints as minimal size == false
      • enforce constraints as maximal size == false
      • layout anchor == ANCHOR_BOTTOM
      • fall back anchors == { ANCHOR_TOP, ANCHOR_BOTTOM, ANCHOR_LEFT, ANCHOR_RIGHT, ANCHOR_GLOBAL }
      • takes focus when visible == false
      Parameters:
      creator - the information control creator

  • Method Details

    • computeInformation

      protected abstract void computeInformation()
      Computes the information to be displayed and the area in which the computed information is valid. Implementation of this method must finish their computation by setting the computation results using setInformation.

    • setInformation

      protected final void setInformation(String information, Rectangle subjectArea)
      Sets the parameters of the information to be displayed. These are the information itself and the area for which the given information is valid. This so called subject area is a graphical region of the information control's subject control. This method calls presentInformation() to trigger the presentation of the computed information.
      Parameters:
      information - the information, or null if none is available
      subjectArea - the subject area, or null if none is available

    • setInformation

      protected final void setInformation(Object information, Rectangle subjectArea)
      Sets the parameters of the information to be displayed. These are the information itself and the area for which the given information is valid. This so called subject area is a graphical region of the information control's subject control. This method calls presentInformation() to trigger the presentation of the computed information.
      Parameters:
      information - the information, or null if none is available
      subjectArea - the subject area, or null if none is available
      Since:
      2.1

    • setCloser

      protected void setCloser(AbstractInformationControlManager.IInformationControlCloser closer)
      Sets the information control closer for this manager.
      Parameters:
      closer - the information control closer for this manager

    • setMargins

      public void setMargins(int xMargin, int yMargin)
      Sets the horizontal and vertical margin to be used when laying out the information control relative to the subject control.
      Parameters:
      xMargin - the x-margin
      yMargin - the y-Margin

    • setSizeConstraints

      public void setSizeConstraints(int widthInChar, int heightInChar, boolean enforceAsMinimalSize, boolean enforceAsMaximalSize)
      Sets the width- and height constraints of the information control.
      Parameters:
      widthInChar - the width constraint in number of characters
      heightInChar - the height constrain in number of characters
      enforceAsMinimalSize - indicates whether the constraints describe the minimal allowed size of the control
      enforceAsMaximalSize - indicates whether the constraints describe the maximal allowed size of the control

    • setRestoreInformationControlBounds

      public void setRestoreInformationControlBounds(IDialogSettings dialogSettings, boolean restoreLocation, boolean restoreSize)
      Tells this information control manager to open the information control with the values contained in the given dialog settings and to store the control's last valid size in the given dialog settings.

      Note: This API is only valid if the information control implements IInformationControlExtension3. Not following this restriction will later result in an UnsupportedOperationException.

      The constants used to store the values are:

      Parameters:
      dialogSettings - the dialog settings
      restoreLocation - true iff the location is must be (re-)stored
      restoreSize - trueiff the size is (re-)stored
      Since:
      3.0

    • setAnchor

      public void setAnchor(AbstractInformationControlManager.Anchor anchor)
      Sets the anchor used for laying out the information control relative to the subject control. E.g, using ANCHOR_TOP indicates that the information control is position above the area for which the information to be displayed is valid.
      Parameters:
      anchor - the layout anchor

    • setFallbackAnchors

      public void setFallbackAnchors(AbstractInformationControlManager.Anchor[] fallbackAnchors)
      Sets the anchors fallback sequence used to layout the information control if the original anchor can not be used because the information control would not fit in the display client area.

      The fallback anchor for a given anchor is the one that comes directly after the given anchor or is the first one in the sequence if the given anchor is the last one in the sequence.

      Note: This sequence is ignored if the original anchor is not contained in this list.

      Parameters:
      fallbackAnchors - the array with the anchor fallback sequence
      See Also:

    • setCustomInformationControlCreator

      protected void setCustomInformationControlCreator(IInformationControlCreator informationControlCreator)
      Sets the temporary custom control creator, overriding this manager's default information control creator.
      Parameters:
      informationControlCreator - the creator, possibly null
      Since:
      3.0

    • takesFocusWhenVisible

      public void takesFocusWhenVisible(boolean takesFocus)
      Tells the manager whether it should set the focus to the information control when made visible.
      Parameters:
      takesFocus - true if information control should take focus when made visible

    • isTakingFocusWhenVisible

      protected boolean isTakingFocusWhenVisible()
      Tells whether the control takes focus when visible.
      Returns:
      true if the control takes focus when visible, false otherwise
      Since:
      3.7

    • handleSubjectControlDisposed

      protected void handleSubjectControlDisposed()
      Handles the disposal of the subject control. By default, the information control is disposed by calling disposeInformationControl. Subclasses may extend this method.

    • install

      public void install(Control subjectControl)
      Installs this manager on the given control. The control is now taking the role of the subject control. This implementation sets the control also as the information control closer's subject control and automatically enables this manager.
      Parameters:
      subjectControl - the subject control

    • getSubjectControl

      protected Control getSubjectControl()
      Returns the subject control of this manager/information control.
      Returns:
      the subject control

    • getSubjectArea

      protected Rectangle getSubjectArea()
      Returns the actual subject area.
      Returns:
      the actual subject area

    • setEnabled

      @Deprecated public void setEnabled(boolean enabled)
      Deprecated.
      visibility will be changed to protected
      Sets the enable state of this manager.
      Parameters:
      enabled - the enable state

    • isEnabled

      protected boolean isEnabled()
      Returns whether this manager is enabled or not.
      Returns:
      true if this manager is enabled otherwise false

    • computeSizeConstraints

      protected Point computeSizeConstraints(Control subjectControl, IInformationControl informationControl)
      Computes the size constraints of the information control in points based on the default font of the given subject control as well as the size constraints in character width.
      Parameters:
      subjectControl - the subject control
      informationControl - the information control whose size constraints are computed
      Returns:
      the computed size constraints in points

    • computeSizeConstraints

      protected Point computeSizeConstraints(Control subjectControl, Rectangle subjectArea, IInformationControl informationControl)
      Computes the size constraints of the information control in points.
      Parameters:
      subjectControl - the subject control
      subjectArea - the subject area
      informationControl - the information control whose size constraints are computed
      Returns:
      the computed size constraints in points
      Since:
      3.0

    • handleInformationControlDisposed

      protected void handleInformationControlDisposed()
      Handles the disposal of the information control. By default, the information control closer is stopped.

    • getInformationControl

      protected IInformationControl getInformationControl()
      Returns the information control. If the information control has not been created yet, it is automatically created.
      Returns:
      the information control

    • computeLocation

      protected Point computeLocation(Rectangle subjectArea, Point controlSize, AbstractInformationControlManager.Anchor anchor)
      Computes the display location of the information control. The location is computed considering the given subject area, the anchor at the subject area, and the size of the information control. This method does not care about whether the information control would be completely visible when placed at the result location.
      Parameters:
      subjectArea - the subject area
      controlSize - the size of the information control
      anchor - the anchor at the subject area
      Returns:
      the display location of the information control

    • computeAvailableArea

      protected Rectangle computeAvailableArea(Rectangle subjectArea, Rectangle bounds, AbstractInformationControlManager.Anchor anchor)
      Computes the area available for an information control given an anchor and the subject area within bounds.
      Parameters:
      subjectArea - the subject area
      bounds - the bounds
      anchor - the anchor at the subject area
      Returns:
      the area available at the given anchor relative to the subject area, confined to the monitor's client area
      Since:
      3.3

    • updateLocation

      protected boolean updateLocation(Point location, Point size, Rectangle displayArea, AbstractInformationControlManager.Anchor anchor)
      Checks whether a control of the given size at the given location would be completely visible in the given display area when laid out by using the given anchor. If not, this method tries to shift the control orthogonal to the direction given by the anchor to make it visible. If possible it updates the location.

      This method returns true if the potentially updated position results in a completely visible control, or false otherwise.

      Parameters:
      location - the location of the control
      size - the size of the control
      displayArea - the display area in which the control should be visible
      anchor - anchor for lying out the control
      Returns:
      trueif the updated location is useful

    • getNextFallbackAnchor

      protected AbstractInformationControlManager.Anchor getNextFallbackAnchor(AbstractInformationControlManager.Anchor anchor)
      Returns the next fallback anchor as specified by this manager's fallback anchor sequence.

      The fallback anchor for the given anchor is the one that comes directly after the given anchor or is the first one in the sequence if the given anchor is the last one in the sequence.

      Note: It is the callers responsibility to prevent an endless loop i.e. to test whether a given anchor has already been used once. then

      Parameters:
      anchor - the current anchor
      Returns:
      the next fallback anchor or null if no fallback anchor is available

    • computeInformationControlLocation

      protected Point computeInformationControlLocation(Rectangle subjectArea, Point controlSize)
      Computes the location of the information control depending on the subject area and the size of the information control. This method attempts to find a location at which the information control lies completely in the display's client area while honoring the manager's default anchor. If this isn't possible using the default anchor, the fallback anchors are tried out.
      Parameters:
      subjectArea - the information area
      controlSize - the size of the information control
      Returns:
      the computed location of the information control

    • showInformation

      public void showInformation()
      Computes information to be displayed as well as the subject area and initiates that this information is presented in the information control. This happens only if this controller is enabled.

    • doShowInformation

      protected void doShowInformation()
      Computes information to be displayed as well as the subject area and initiates that this information is presented in the information control.

    • presentInformation

      protected void presentInformation()
      Presents the information in the information control or hides the information control if no information should be presented. The information has previously been set using setInformation.

      This method should only be called from overriding methods or from setInformation.

    • hideInformationControl

      protected void hideInformationControl()
      Hides the information control and stops the information control closer.

    • canClearDataOnHide

      protected boolean canClearDataOnHide()
      Tells whether internal data can be cleared on hide.
      Returns:
      true if data can be cleared on hide
      Since:
      3.6
      See Also:

    • showInformationControl

      protected void showInformationControl(Rectangle subjectArea)
      Shows the information control and starts the information control closer. This method may not be called by clients.
      Parameters:
      subjectArea - the information area

    • disposeInformationControl

      public void disposeInformationControl()
      Disposes this manager's information control.

    • dispose

      public void dispose()
      Disposes this manager and if necessary all dependent parts such as the information control. For symmetry it first disables this manager.

    • storeInformationControlBounds

      protected void storeInformationControlBounds()
      Stores the information control's bounds.
      Since:
      3.0

    • restoreInformationControlBounds

      protected Rectangle restoreInformationControlBounds()
      Restores the information control's bounds.
      Returns:
      the stored bounds
      Since:
      3.0

    • getInternalAccessor

      public org.eclipse.jface.internal.text.InternalAccessor getInternalAccessor()
      Returns an adapter that gives access to internal methods.

      Note: This method is not intended to be referenced or overridden by clients.

      Returns:
      the replaceable information control accessor
      Since:
      3.4
      Restriction:
      This method is not intended to be referenced by clients.
      Restriction:
      This method is not intended to be re-implemented or extended by clients.