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HTMEngine

HTMEngine Component

v. 2.0

API specification. Notification messages.

Table of content:
  1. Generic notification messages
    1. NM_CLICK
    2. NM_DBLCLK
    3. NM_SETFOCUS
    4. NM_KILLFOCUS
    5. NM_NCHITTEST
    6. NM_SETCURSOR
    7. NM_KEYDOWN
    8. NM_CHAR
    9. NM_RELEASEDCAPTURE
  2. HTMEngine specific notification messages
    1. HEN_CREATE_CONTROL
    2. HEN_CONTROL_CREATED
    3. HEN_LOAD_DATA
    4. HEN_HYPERLINK
    5. HEN_DOCUMENT_COMPLETE
    6. HEN_UPDATE_UI

1. Generic notification messages

1.1. NM_CLICK

Notifies a control's parent window that the user has clicked the left mouse button within the control. NM_CLICK is sent in the form of a WM_NOTIFY message.

NM_CLICK
 lpnm = (LPHEN_MOUSE) lParam;

Parameters

lpnm
Address of an HEN_MOUSE structure that contains additional information about this notification message.
typedef struct tagNMHE_MOUSE
{
  NMHDR   hdr;
  DWORD   hitCode;        // one of HEHitCodes
  DWORD   hitId;          // internal dom element id
  POINT   pt;             // cursor position
  LPARAM  lParam;         // lParam of original message
  WPARAM  wParam;         // wParam of original message
  LPCWSTR hyperlinkUri;   // uri of hyperlink or zero, zero terminated wide string
  LPCWSTR hyperlinkName;  // name of hyperlink or zero, zero terminated string
  RECT    hyperlinkPlace; // outline of hyperlink
  DWORD   reserved1;
  DWORD   reserved2;
} NMHE_MOUSE, FAR *LPNMHE_MOUSE;
 
// hitCode values.
enum HEHitCodes
{
   HEHC_NONE = 0,
   HEHC_TEXT = 1,
   HEHC_HYPERLINK = 2,
   HEHC_SELECTION = 3,
   HEHC_TEXT_DRAG = 0x10
};
 

Return Values

The return value is ignored by the control.

Notifies a control's parent window that the user has double-clicked the left mouse button within the control. NM_DBLCLK is sent in the form of a WM_NOTIFY message.

NM_DBLCLK
 lpnm = (LPHEN_MOUSE) lParam;

Parameters

lpnm
Address of an HEN_MOUSE structure that contains additional information about this notification message.
Return Values

The return value is ignored by the control.

Notifies a control's parent window that the control has received the input focus. NM_SETFOCUS is sent in the form of a WM_NOTIFY message.

NM_SETFOCUS
 lpnm = (LPNMHDR) lParam;

Parameters

lpnm
Address of an NMHDR structure that contains additional information about this notification message.
Return Values

The return value is ignored by the control.

Notifies a control's parent window that the control has lost the input focus. NM_KILLFOCUS is sent in the form of a WM_NOTIFY message.

NM_KILLFOCUS
 lpnm = (LPNMHDR) lParam;

Parameters

lpnm
Address of an NMHDR structure that contains additional information about this notification message.
Return Values

The return value is ignored by the control.

Sent by a control when the control receives a WM_NCHITTEST message. This notification is sent in the form of a WM_NOTIFY message.

NM_NCHITTEST
 lpnm = (LPHEN_MOUSE) lParam;

Parameters

lpnm
Address of an HEN_MOUSE structure that contains additional information about this notification message.
Return Values

The return value is ignored by the control.

Notifies a control's parent window that the control is setting the cursor in response to a WM_SETCURSOR message. This notification is sent in the form of a WM_NOTIFY message.

NM_SETCURSOR
 lpnm = (LPHEN_MOUSE) lParam;

Parameters

lpnm
Address of an HEN_MOUSE structure that contains additional information about this notification message.
Return Values

Returns nonzero to allow the control to set the cursor or zero to prevent the control from setting the cursor, unless otherwise specified.

Sent by a control when the control has the keyboard focus and the user presses a key. This notification is sent in the form of a WM_NOTIFY message.

NM_KEYDOWN
   lpnmk = (LPNMKEY) lParam;

Parameters

lpnmk
Address of an NMKEY structure that contains additional information about the key that caused the notification message.
Return Values

Return nonzero to prevent the control from processing the key, or zero otherwise.

1.8. NM_CHAR

The NM_CHAR notification message is sent by a control when a character key is processed. This notification is sent in the form of a WM_NOTIFY message.

NM_CHAR
   lpnmk = (LPNMKEY) lParam;

Parameters

lpnmk
Address of an NMKEY structure that contains additional information about the key that caused the notification message.
Return Values

Return nonzero to prevent the control from processing the key, or zero otherwise.

Notifies a control's parent window that the control is releasing mouse capture. This notification is sent in the form of a WM_NOTIFY message.

NM_RELEASEDCAPTURE
   lpnmh = (LPNMHDR) lParam;

Parameters

lpnmh
Address of an NMHDR structure that contains additional information about this notification message.
Return Values

The control ignores the return value from this notification.

2. HTMEngine specific notification messages

2.1. HEN_CREATE_CONTROL

Notifies HtmLayout control's parent window that HtmLayout is about to create a child control. The application can override the creation of "standard HTML controls" or implement the creation of other application specific controls.

This notification message is sent in the form of a WM_NOTIFY message.

HLN_CREATE_CONTROL
  phlcc = (LPNMHL_CREATE_CONTROL) lParam;

Return Values

No return value.

Parameters

phlcc
Address of a NMHL_CREATE_CONTROL structure:
 
struct NMHL_CREATE_CONTROL
{
NMHDR hdr;  
// some frequently used attributes:
LPCWSTR type; //zero terminated string, type attribute value, e.g. "text","textarea","checkbox"
LPCWSTR name; //zero terminated string, name attribute value
LPCWSTR id; //zero terminated string, id attribute value
int tagType; // 0-input, 1-textarea, 2-select, 3-widget
// full set of attributes:
LPCSTR*    attributeNames; // vector of pointers to attribute names (zero terminated char strings)
LPCWSTR* attributeValues; // vector of pointers to attribute values (zero terminated wchar_t strings)
int attributeCount; // size of attribute names and values vectors
//<SELECT> and <WIDGET> collection of <OPTION>'s or <PARAM>'s:
LPCWSTR* optionNames; // vector of pointers to param names (wchar_t strings)
LPCWSTR* optionValues; // vector of pointers to param values (wchar_t strings)
int optionCount; // size of option names and values vectors
//output parameter
HWND outControlHwnd; // HWND of created control or HWND_TRY_DEFAULT or HWND_DISCARD_CREATION
}

Notifies HtmLayout control's parent window that control has been created either by HtmLayout or by host application.

This notification message is sent in the form of a WM_NOTIFY message.

HEN_CONTROL_CREATED
  phlcc = (LPNMHL_CREATE_CONTROL) lParam;
 


Return Values




No return value.



Parameters




phlcc




Address of a NMHL_CREATE_CONTROL structure:


 



NMHL_CREATE_CONTROL.outControlHwnd field contains valid window handler.  







Notifies HtmLayout control's parent window that HtmLayout is about to download a referred resource. Currently, only images are classified as such, but in later versions other referred resources will be supported. The application can override this built-in loader and implement loading of resources in its own way (e.g. images may be loaded from database or other resource).


This notification message is sent in the form of a WM_NOTIFY message.





  

    
HEN_LOAD_DATA
    phlld = (LPNMHL_LOAD_DATA) lParam;


  






Return Values




No return value.



Parameters


phlld




Address of a NMHL_LOAD_DATA structure:


 


struct NMHL_LOAD_DATA


{





  

    NMHDR
    hdr;
     
  

  

    //input parameter:
  

  

    LPCWSTR
    uri;
    //zero terminated string, fully qualified uri, e.g. "http://server/folder/file.ext"
  

  

    //output parameters:
  

  

    LPVOID   
    outData;
    // out, pointer to loaded data. HtmLayout will not store outData pointer internally
  

  

    DWORD
    outDataSize;
    // out, loaded data size
  







}







Notifies HtmLayout control's parent window about "hyperlink events" : mouse enter, leave or click on the hyperlink.


This notification message is sent in the form of a WM_NOTIFY message.





  

    
HEN_HYPERLINK
    phlh = (LPNMHL_HYPERLINK) lParam;


  






Return Values




No return value.



Parameters


phlld




Address of a NMHL_HYPERLINK structure:


 


struct NMHL_HYPERLNK


{





  

    NMHDR
    hdr;
     
  

  

    //input parameters:
  

  

    LPCWSTR
    name;
    //value of name attribute of <A> tag. Zero terminated wchar_t string
  

  

    LPCWSTR
    href;
    //value of href attribute of <A> tag, URI. Zero terminated wchar_t string
  

  

    LPCWSTR
    target;
    //value of target attribute of <A> tag. Zero terminated wchar_t string
  

  

    DWORD
    status;
    //subtype of event, one of HL_HYPERLINK_LEAVE, HL_HYPERLINK_ENTER, HL_HYPERLINK_CLICK values
  







}






Notifies HtmLayout control's parent window that HtmLayout finished loading all resources associated with the loaded document. There are four methods which will trigger this notification:


    

  1. WM_HE_LOAD_FILE,
    2. 

  2. WM_HE_LOAD_HTML,
    3. 

  3. WM_HE_INSERT_HTML,
    4. 

  4. WM_HE_PASTE



If document or document fragment to be loaded has no external (with URIs start with http: https: ftp:) resources HTMEngine will send this notification "inside" a call of these methods. If document contains at least one external resource HTMEngine will send this notification asynchronously after loading of all such resources.


This notification message is sent in the form of a WM_NOTIFY message.





  

    

HEN_DOCUMENT_COMPLETE


  lpnm = (LPNMHDR) lParam;

  






Parameters


lpnm




Address of an NMHDR structure that contains additional information about this notification message.



Return Values


The return value is ignored by the control.





Notifies HtmLayout control's parent window that caret position, selection or status of formatting registers has been changed. This notification message is sent in the form of a WM_NOTIFY message.





  

    

HEN_UPDATE_UI


  lpnm = (LPNMHE_UPDATE_UI) lParam;

  






Parameters


lpnm




Address of an NMHE_UPDATE_UI structure that contains additional information about this notification message:





  

    

struct NMHE_UPDATE_UI


{


    NMHDR     hdr;


    RECT      coorAnchor; // coordinates of anchor rectangle


    RECT      coorCaret;  // coordinates of caret rectangle


    DWORD     reserved1;


    DWORD     reserved2;


    DWORD     reserved3;


    DWORD     reserved4;


    DWORD     reserved5;


};

  








 



Return Values


The return value is ignored by the control.


 


							
				

				

					
			
	
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