remove wxTextAttr::CreateFont(); return wxNullFont from GetFont() if we have no font...

[wxWidgets.git] / interface / html / htmlcell.h

/////////////////////////////////////////////////////////////////////////////
// Name:        html/htmlcell.h
// Purpose:     documentation for wxHtmlColourCell class
// Author:      wxWidgets team
// RCS-ID:      $Id$
// Licence:     wxWindows license
/////////////////////////////////////////////////////////////////////////////

/**
    @class wxHtmlColourCell
    @headerfile htmlcell.h wx/html/htmlcell.h

    This cell changes the colour of either the background or the foreground.

    @library{wxhtml}
    @category{FIXME}
*/
class wxHtmlColourCell : public wxHtmlCell
{
public:
    /**
        Constructor.
        
        @param clr
            The color
        @param flags
            Can be one of following:
        
        
        
        
        
        
            wxHTML_CLR_FOREGROUND
        
        
        
        
            change color of text
        
        
        
        
        
            wxHTML_CLR_BACKGROUND
        
        
        
        
            change background color
    */
    wxHtmlColourCell(wxColour clr, int flags = wxHTML_CLR_FOREGROUND);
};


/**
    @class wxHtmlWidgetCell
    @headerfile htmlcell.h wx/html/htmlcell.h

    wxHtmlWidgetCell is a class that provides a connection between HTML cells and
    widgets (an object derived
    from wxWindow). You can use it to display things like forms, input boxes etc.
    in an HTML window.

    wxHtmlWidgetCell takes care of resizing and moving window.

    @library{wxhtml}
    @category{FIXME}
*/
class wxHtmlWidgetCell : public wxHtmlCell
{
public:
    /**
        Constructor.
        
        @param wnd
            Connected window. It is parent window must be the wxHtmlWindow object within
            which it is displayed!
        @param w
            Floating width. If non-zero width of wnd window is adjusted so that it is
            always w percents of parent container's width. (For example w = 100 means
        that the window
            will always have same width as parent container)
    */
    wxHtmlWidgetCell(wxWindow* wnd, int w = 0);
};


/**
    @class wxHtmlCell
    @headerfile htmlcell.h wx/html/htmlcell.h

    Internal data structure. It represents fragments of parsed HTML
    page, the so-called @b cell - a word, picture, table, horizontal line and so on.
    It is used by wxHtmlWindow and
    wxHtmlWinParser to represent HTML page in memory.

    You can divide cells into two groups : @e visible cells with non-zero width and
    height and @e helper cells (usually with zero width and height) that
    perform special actions such as color or font change.

    @library{wxhtml}
    @category{FIXME}

    @seealso
    @ref overview_cells "Cells Overview", wxHtmlContainerCell
*/
class wxHtmlCell : public wxObject
{
public:
    /**
        Constructor.
    */
    wxHtmlCell();

    /**
        This method is used to adjust pagebreak position. The parameter is
        variable that contains y-coordinate of page break (= horizontal line that
        should not be crossed by words, images etc.). If this cell cannot be divided
        into two pieces (each one on another page) then it moves the pagebreak
        few pixels up.
        Returns @true if pagebreak was modified, @false otherwise
        Usage:
    */
    virtual bool AdjustPagebreak(int* pagebreak);

    /**
        Renders the cell.
        
        @param dc
            Device context to which the cell is to be drawn
        @param x,y
            Coordinates of parent's upper left corner (origin). You must
            add this to m_PosX,m_PosY when passing coordinates to dc's methods
            Example : dc - DrawText("hello", x + m_PosX, y + m_PosY)
        @param view_y1
            y-coord of the first line visible in window. This is
            used to optimize rendering speed
        @param view_y2
            y-coord of the last line visible in window. This is
            used to optimize rendering speed
    */
    virtual void Draw(wxDC& dc, int x, int y, int view_y1,
                      int view_y2);

    /**
        This method is called instead of Draw() when the
        cell is certainly out of the screen (and thus invisible). This is not
        nonsense - some tags (like wxHtmlColourCell
        or font setter) must be drawn even if they are invisible!
        
        @param dc
            Device context to which the cell is to be drawn
        @param x,y
            Coordinates of parent's upper left corner. You must
            add this to m_PosX,m_PosY when passing coordinates to dc's methods
            Example : dc - DrawText("hello", x + m_PosX, y + m_PosY)
    */
    virtual void DrawInvisible(wxDC& dc, int x, int y);

    /**
        Returns pointer to itself if this cell matches condition (or if any of the cells
        following in the list matches), @NULL otherwise.
        (In other words if you call top-level container's Find it will
        return pointer to the first cell that matches the condition)
        It is recommended way how to obtain pointer to particular cell or
        to cell of some type (e.g. wxHtmlAnchorCell reacts on
        wxHTML_COND_ISANCHOR condition)
        
        @param condition
            Unique integer identifier of condition
        @param param
            Optional parameters
    */
    virtual const wxHtmlCell* Find(int condition, const void* param);

    /**
        Returns descent value of the cell (m_Descent member).
        See explanation:
    */
    int GetDescent();

    /**
        Returns pointer to the first cell in the list.
        You can then use child's GetNext()
        method to obtain pointer to the next cell in list.
        @b Note: This shouldn't be used by the end user. If you need some way of
        finding particular cell in the list, try Find() method
        instead.
    */
    wxHtmlCell* GetFirstChild();

    /**
        Returns height of the cell (m_Height member).
    */
    int GetHeight();

    /**
        Returns unique cell identifier if there is any, empty string otherwise.
    */
    virtual wxString GetId();

    /**
        Returns hypertext link if associated with this cell or @NULL otherwise.
        See wxHtmlLinkInfo.
        (Note: this makes sense only for visible tags).
        
        @param x,y
            Coordinates of position where the user pressed mouse button.
            These coordinates are used e.g. by COLORMAP. Values are relative to the
            upper left corner of THIS cell (i.e. from 0 to m_Width or m_Height)
    */
    virtual wxHtmlLinkInfo* GetLink(int x = 0, int y = 0);

    /**
        Returns cursor to show when mouse pointer is over the cell.
        
        @param window
            interface to the parent HTML window
    */
    virtual wxCursor GetMouseCursor(wxHtmlWindowInterface* window);

    /**
        Returns pointer to the next cell in list (see htmlcell.h if you're
        interested in details).
    */
    wxHtmlCell* GetNext();

    /**
        Returns pointer to parent container.
    */
    wxHtmlContainerCell* GetParent();

    /**
        Returns X position within parent (the value is relative to parent's
        upper left corner). The returned value is meaningful only if
        parent's Layout() was called before!
    */
    int GetPosX();

    /**
        Returns Y position within parent (the value is relative to parent's
        upper left corner). The returned value is meaningful only if
        parent's Layout() was called before!
    */
    int GetPosY();

    /**
        Returns width of the cell (m_Width member).
    */
    int GetWidth();

    /**
        This method performs two actions:
         adjusts the cell's width according to the fact that maximal possible width is
        @e w.
        (this has sense when working with horizontal lines, tables etc.)
         prepares layout (=fill-in m_PosX, m_PosY (and sometimes m_Height) members)
        based on actual width @e w
        It must be called before displaying cells structure because
        m_PosX and m_PosY are undefined (or invalid)
        before calling Layout.
    */
    virtual void Layout(int w);

    /**
        This function is simple event handler. Each time the user clicks mouse button
        over a cell within wxHtmlWindow this method of that
        cell is called. Default behavior is to call
        wxHtmlWindow::LoadPage.
        
        @param window
            interface to the parent HTML window
        @param pos
            coordinates of mouse click (this is relative to cell's origin
        @param event
            mouse event that triggered the call
        
        @returns @true if a link was clicked, @false otherwise.
    */
    virtual bool ProcessMouseClick(wxHtmlWindowInterface* window,
                                   const wxPoint& pos,
                                   const wxMouseEvent& event);

    /**
        Sets unique cell identifier. Default value is no identifier, i.e. empty string.
    */
    void SetId(const wxString& id);

    /**
        Sets the hypertext link associated with this cell. (Default value
        is wxHtmlLinkInfo("", "") (no link))
    */
    void SetLink(const wxHtmlLinkInfo& link);

    /**
        Sets the next cell in the list. This shouldn't be called by user - it is
        to be used only by wxHtmlContainerCell::InsertCell.
    */
    void SetNext(wxHtmlCell cell);

    /**
        Sets parent container of this cell. This is called from
        wxHtmlContainerCell::InsertCell.
    */
    void SetParent(wxHtmlContainerCell p);

    /**
        Sets the cell's position within parent container.
    */
    void SetPos(int x, int y);
};


/**
    @class wxHtmlContainerCell
    @headerfile htmlcell.h wx/html/htmlcell.h

    The wxHtmlContainerCell class is an implementation of a cell that may
    contain more cells in it. It is heavily used in the wxHTML layout algorithm.

    @library{wxhtml}
    @category{FIXME}

    @seealso
    @ref overview_cells "Cells Overview"
*/
class wxHtmlContainerCell : public wxHtmlCell
{
public:
    /**
        Constructor. @a parent is pointer to parent container or @NULL.
    */
    wxHtmlContainerCell(wxHtmlContainerCell parent);

    /**
        Returns container's horizontal alignment.
    */
    int GetAlignHor();

    /**
        Returns container's vertical alignment.
    */
    int GetAlignVer();

    /**
        Returns the background colour of the container or @c wxNullColour if no
        background
        colour is set.
    */
    wxColour GetBackgroundColour();

    /**
        Returns the indentation. @a ind is one of the @b wxHTML_INDENT_* constants.
        @b Note: You must call GetIndentUnits()
        with same @a ind parameter in order to correctly interpret the returned integer
        value.
        It is NOT always in pixels!
    */
    int GetIndent(int ind);

    /**
        Returns the units of indentation for @a ind where @a ind is one
        of the @b wxHTML_INDENT_* constants.
    */
    int GetIndentUnits(int ind);

    /**
        Inserts new cell into the container.
    */
    void InsertCell(wxHtmlCell cell);

    /**
        Sets the container's alignment (both horizontal and vertical) according to
        the values stored in @e tag. (Tags @c ALIGN parameter is extracted.) In fact
        it is only a front-end to SetAlignHor()
        and SetAlignVer().
    */
    void SetAlign(const wxHtmlTag& tag);

    /**
        Sets the container's @e horizontal alignment. During wxHtmlCell::Layout
        each line is aligned according to @a al value.
        
        @param al
            new horizontal alignment. May be one of these values:
        
        
        
        
        
        
            wxHTML_ALIGN_LEFT
        
        
        
        
            lines are left-aligned (default)
        
        
        
        
        
            wxHTML_ALIGN_JUSTIFY
        
        
        
        
            lines are justified
        
        
        
        
        
            wxHTML_ALIGN_CENTER
        
        
        
        
            lines are centered
        
        
        
        
        
            wxHTML_ALIGN_RIGHT
        
        
        
        
            lines are right-aligned
    */
    void SetAlignHor(int al);

    /**
        Sets the container's @e vertical alignment. This is per-line alignment!
        
        @param al
            new vertical alignment. May be one of these values:
        
        
        
        
        
        
            wxHTML_ALIGN_BOTTOM
        
        
        
        
            cells are over the line (default)
        
        
        
        
        
            wxHTML_ALIGN_CENTER
        
        
        
        
            cells are centered on line
        
        
        
        
        
            wxHTML_ALIGN_TOP
        
        
        
        
            cells are under the line
    */
    void SetAlignVer(int al);

    /**
        Sets the background colour for this container.
    */
    void SetBackgroundColour(const wxColour& clr);

    /**
        Sets the border (frame) colours. A border is a rectangle around the container.
        
        @param clr1
            Colour of top and left lines
        @param clr2
            Colour of bottom and right lines
    */
    void SetBorder(const wxColour& clr1, const wxColour& clr2);

    /**
        Sets the indentation (free space between borders of container and subcells).
        
        @param i
            Indentation value.
        @param what
            Determines which of the four borders we're setting. It is OR
            combination of following constants:
        
        
        
        
        
        
            wxHTML_INDENT_TOP
        
        
        
        
            top border
        
        
        
        
        
            wxHTML_INDENT_BOTTOM
        
        
        
        
            bottom
        
        
        
        
        
            wxHTML_INDENT_LEFT
        
        
        
        
            left
        
        
        
        
        
            wxHTML_INDENT_RIGHT
        
        
        
        
            right
        
        
        
        
        
            wxHTML_INDENT_HORIZONTAL
        
        
        
        
            left and right
        
        
        
        
        
            wxHTML_INDENT_VERTICAL
        
        
        
        
            top and bottom
        
        
        
        
        
            wxHTML_INDENT_ALL
        
        
        
        
            all 4 borders
        @param units
            Units of i. This parameter affects interpretation of  value.
        
        
        
        
        
        
            wxHTML_UNITS_PIXELS
        
        
        
        
            i is number of pixels
        
        
        
        
        
            wxHTML_UNITS_PERCENT
        
        
        
        
            i is interpreted as percents of width
            of parent container
    */
    void SetIndent(int i, int what, int units = wxHTML_UNITS_PIXELS);

    /**
        Sets minimal height of the container.
        When container's wxHtmlCell::Layout is called, m_Height
        is set depending on layout of subcells to the height of area covered
        by layed-out subcells. Calling this method guarantees you that the height
        of container is never smaller than @a h - even if the subcells cover
        much smaller area.
        
        @param h
            The minimal height.
        @param align
            If height of the container is lower than the minimum height, empty space
        must be inserted
            somewhere in order to ensure minimal height. This parameter is one of
        wxHTML_ALIGN_TOP,
            wxHTML_ALIGN_BOTTOM, wxHTML_ALIGN_CENTER. It refers to the contents, not to
        the
            empty place.
    */
    void SetMinHeight(int h, int align = wxHTML_ALIGN_TOP);

    //@{
    /**
        Sets floating width adjustment.
        The normal behaviour of container is that its width is the same as the width of
        parent container (and thus you can have only one sub-container per line).
        You can change this by setting FWA.
        @a pixel_scale is number of real pixels that equals to 1 HTML pixel.
        
        @param w
            Width of the container. If the value is negative it means
            complement to full width of parent container (e.g.
            SetWidthFloat(-50, wxHTML_UNITS_PIXELS) sets the width
            of container to parent's width minus 50 pixels. This is useful when
            creating tables - you can call SetWidthFloat(50) and SetWidthFloat(-50))
        @param units
            Units of w This parameter affects the interpretation of  value.
        
        
        
        
        
        
            wxHTML_UNITS_PIXELS
        
        
        
        
            w is number of pixels
        
        
        
        
        
            wxHTML_UNITS_PERCENT
        
        
        
        
            w is interpreted as percents of width
            of parent container
        @param tag
            In the second version of method, w and units
            info is extracted from tag's WIDTH parameter.
    */
    void SetWidthFloat(int w, int units);
    void SetWidthFloat(const wxHtmlTag& tag,
                       double pixel_scale = 1.0);
    //@}
};


/**
    @class wxHtmlLinkInfo
    @headerfile htmlcell.h wx/html/htmlcell.h

    This class stores all necessary information about hypertext
    links (as represented by @c A tag in HTML documents). In
    current implementation it stores URL and target frame name.
    @e Note that frames are not currently supported by wxHTML!

    @library{wxhtml}
    @category{FIXME}
*/
class wxHtmlLinkInfo : public wxObject
{
public:
    //@{
    /**
        Construct hypertext link from HREF (aka URL) and TARGET (name of target
        frame).
    */
    wxHtmlLinkInfo();
    wxHtmlLinkInfo(const wxString& href,
                   const wxString& target = wxEmptyString);
    //@}

    /**
        Return pointer to event that generated OnLinkClicked event. Valid
        only within wxHtmlWindow::OnLinkClicked,
        @NULL otherwise.
    */
    const wxMouseEvent* GetEvent();

    /**
        Return @e HREF value of the @c A tag.
    */
    wxString GetHref();

    /**
        Return pointer to the cell that was clicked. Valid
        only within wxHtmlWindow::OnLinkClicked,
        @NULL otherwise.
    */
    const wxHtmlCell* GetHtmlCell();

    /**
        Return @e TARGET value of the @c A tag (this value
        is used to specify in which frame should be the page pointed
        by @ref gethref() Href opened).
    */
    wxString GetTarget();
};