Support for code completion and function tips

Mar 28 posted in Tech (RSS), comments.

Support for code completion and function tips

From http://www.cppprog.com/2009/1111/176_4.html

VS code completion and function prompt function yes is worth commendable, they can greatly improve the programming Xiaoshuai we (the result that now write code O'clock often Zhi Ji Zhu first four letters, if the Duixiang behind Dianle without prompting after the decimal point will be agitated and confused to say -_-), although sometimes fail.

This function is used as IDE is indispensable D. Even if you only intend to be a editor that if this feature is also a bright spot ah ~ ~ (currently a lot of code editor said no this function).

Some tips on the function command to SCI_CALLTIP as prefix, we will use here only introduce a few commands (more commands see: http://scintilla.sourceforge.net/ScintillaDoc.html # CallTips )

SCI_CALLTIPSHOW (int posStart, const char * definition) display the prompt. posStart said display position, definition content is displayed
SCI_CALLTIPCANCEL cancel Tips
SCI_CALLTIPACTIVE If the current editor, has prompted information, returns 1, otherwise it returns 0
SCI_CALLTIPSETHLT (int highlightStart, int highlightEnd) set the prompt in the highlighted location, where we enter the function in VS when the function argument tips will highlight the current name of the input parameters.

In our program the best time to add tips is SCN_CHARADDED (see previous section) event. When the user enters the left parenthesis '(' time to obtain the function name in parentheses on the left, and then show the full definition of the function.

The following code implements two API CreateWindow function and MoveWindow Tips

/ / We have to highlight the two functions
const size_t FUNCSIZE = 2;
char * g_szFuncList [FUNCSIZE] = (/ / function name
"CreateWindow (",
"MoveWindow ("
);
char * g_szFuncDesc [FUNCSIZE] = (/ / Function Information
"HWND CreateWindow ("
"LPCTSTR lpClassName,"
"LPCTSTR lpWindowName,"
"DWORD dwStyle,"
"Int x,"
"Int y,"
"Int nWidth,"
"Int nHeight,"
"HWND hWndParent,"
"HMENU hMenu,"
"HANDLE hInstance,"
"PVOID lpParam"
")"
"BOOL MoveWindow ("
"HWND hWnd,"
"Int X,"
"Int Y,"
"Int nWidth,"
"Int nHeight,"
"BOOL bRepaint"
")"
);
void __fastcall TForm1:: WndProc (Messages:: TMessage & Message)
(
TForm:: WndProc (Message);
if (Message.Msg == WM_NOTIFY)
(
SCNotification * notify = (SCNotification *) Message.LParam;
...
if (notify-> nmhdr.code == SCN_CHARADDED)
(
...
/ / Function prompt function
static const char * pCallTipNextWord = NULL; / / highlight the location of the next
static const char * pCallTipCurDesc = NULL; / / current function information prompted
if (notify-> ch == '(') / / If you enter a left parenthesis, indicating the function prompt
(
char word [1000]; / / save the current word under the cursor (function name)
TextRange tr; / / command for SCI_GETTEXTRANGE
int pos = SendEditor (SCI_GETCURRENTPOS); / / get the current position (the position in parentheses)
int startpos = SendEditor (SCI_WORDSTARTPOSITION, pos-1); / / starting position of the current word
int endpos = SendEditor (SCI_WORDENDPOSITION, pos-1); / / terminate the current position of the word
tr.chrg.cpMin = startpos; / / set word interval, remove the word
tr.chrg.cpMax = endpos;
tr.lpstrText = word;
SendEditor (SCI_GETTEXTRANGE, 0, sptr_t (& tr));
for (size_t i = 0; i <FUNCSIZE; i + +) / / Zhao Zhao have not we realize the function?
(
if (memcmp (g_szFuncList [i], word, sizeof (g_szFuncList [i])) == 0)
(/ / Find the friends, then it prompts
pCallTipCurDesc = g_szFuncDesc [i]; / / current function information prompted
SendEditor (SCI_CALLTIPSHOW, pos, sptr_t (pCallTipCurDesc ));// Show this tip
const char * pStart = strchr (pCallTipCurDesc ,'(')+ 1; / / highlight the first parameter
const char * pEnd = strchr (pStart ,',');// comma-separated list of parameters
if (pEnd == NULL) pEnd = strchr (pStart ,')');// if the last parameter, followed by the right parenthesis
SendEditor (SCI_CALLTIPSETHLT,
pStart-pCallTipCurDesc, pEnd-pCallTipCurDesc);
pCallTipNextWord = pEnd +1; / / point to next parameter position
break;
)
)
)
else if (notify-> ch == ')') / / If you enter the right parentheses, prompts to close the function
(
SendEditor (SCI_CALLTIPCANCEL);
pCallTipCurDesc = NULL;
pCallTipNextWord = NULL;
)
else if (notify-> ch == ',' & & SendEditor (SCI_CALLTIPACTIVE) & & pCallTipCurDesc)
(
/ / Input is a comma, highlight the next parameter
const char * pStart = pCallTipNextWord;
const char * pEnd = strchr (pStart ,',');
if (pEnd == NULL) pEnd = strchr (pStart ,')');
if (pEnd == NULL) / / no next argument the matter, close the prompt
SendEditor (SCI_CALLTIPCANCEL);
else
(
SendEditor (SCI_CALLTIPSETHLT, pStart-pCallTipCurDesc, pEnd-pCallTipCurDesc);
pCallTipNextWord = pEnd +1;
)
)
) / / If (notify-> nmhdr.code == SCN_CHARADDED)
...
) / / If (Message.Msg == WM_NOTIFY)
)

Of course, this prompts a considerable cottage friends. Such as the function name and a space between the parentheses is not prompted to come out, the function will prompt the last nested call a function parameter. If the improvements on, we fancy takes it.

In addition, there is a mention of foreign words, in actual use, the information that we can not function the same as here, death is written, but based on user input dynamically generated list of function names and information. This involves a C + + code to resolve the problem (okay, as long as the analytic function declaration on the line), to this point, cattle X, students can write their own parsing code; times cattle X, consider using WAVE, Spirit, Regex, etc. Library to help resolve; Xiang Niu Di students even Zhezhong Bu, consider using CTAGS Gongju generated in a background thread tag Wen Jian, Women from the tag file can be a li Qu (Dangran, Xiaoshuai Well ~ ~ can refer to the Han Shu C + + Builder Tips efficiency -_-)。

Code completion and function similar to the usage of tips, the prefix is SCI_AUTOC, specific command, see: http://scintilla.sourceforge.net/ScintillaDoc.html # Autocompletion

Directly on the code:

void __fastcall TForm1:: WndProc (Messages:: TMessage & Message)
(
TForm:: WndProc (Message);
if (Message.Msg == WM_NOTIFY)
(
...
if (notify-> nmhdr.code == SCN_CHARADDED)
(
...
if (notify-> ch == '.')
(
char word [1000]; / / save the current word under the cursor
TextRange tr; / / command for SCI_GETTEXTRANGE
int pos = SendEditor (SCI_GETCURRENTPOS); / / get the current position
int startpos = SendEditor (SCI_WORDSTARTPOSITION, pos-1); / / starting position of the current word
int endpos = SendEditor (SCI_WORDENDPOSITION, pos-1); / / terminate the current position of the word
tr.chrg.cpMin = startpos; / / set word interval, remove the word
tr.chrg.cpMax = endpos;
tr.lpstrText = word;
SendEditor (SCI_GETTEXTRANGE, 0, sptr_t (& tr));
if (strcmp (word, "file.") == 0) / / input file. After the object file suggest several ways
(
SendEditor (SCI_AUTOCSHOW, 0,
sptr_t (
"Close"
"Eof"
"Good"
"Open"
"Rdbuf"
"Size"
));
)
)
...

SCI_AUTOCSHOW first argument of command that have entered the number of characters. This is useful for code completion, such that we can use it to help the user to enter long strings of words, such as: