From 2abb9d2f1716177aa6c0ce0fd6a2519580dc12af Mon Sep 17 00:00:00 2001
From: Vadim Zeitlin <vadim@wxwidgets.org>
Date: Sat, 25 Jan 2003 23:47:33 +0000
Subject: [PATCH] added wxArray::SetCount()
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@18930 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
---
docs/latex/wx/array.tex | 14 ++++++++++++
include/wx/dynarray.h | 12 +++++-----
src/common/dynarray.cpp | 50 +++++++++++++++++++++++++++++++++--------
3 files changed, 62 insertions(+), 14 deletions(-)
diff --git a/docs/latex/wx/array.tex b/docs/latex/wx/array.tex
index c493cd1fb7..aa07dce168 100644
--- a/docs/latex/wx/array.tex
+++ b/docs/latex/wx/array.tex
@@ -201,6 +201,7 @@ does exactly the same as \helpref{Item()}{wxarrayitem} method.
\helpref{Add}{wxarrayadd}\\
\helpref{Insert}{wxarrayinsert}\\
+\helpref{SetCount}{wxarraysetcount}\\
\helpref{WX\_APPEND\_ARRAY}{wxappendarray}
\membersection{Removing items}
@@ -590,6 +591,19 @@ array.RemoveAt(n)
See also \helpref{WX\_CLEAR\_ARRAY}{wxcleararray} macro which deletes all
elements of a wxArray (supposed to contain pointers).
+\membersection{wxArray::SetCount}\label{wxarraysetcount}
+
+\func{void}{SetCount}{\param{size\_t }{count}, \param{T }{defval = T($0$)}}
+
+This function ensures that the number of array elements is at least
+{\it count}. If the array has already {\it count} or mroe items, nothing is
+done. Otherwise, {\tt count - GetCount()} elements are added and initialized to
+the value {\it defval}.
+
+\wxheading{See also}
+
+\helpref{GetCount}{wxarraygetcount}
+
\membersection{wxArray::Shrink}\label{wxarrayshrink}
\func{void}{Shrink}{\void}
diff --git a/include/wx/dynarray.h b/include/wx/dynarray.h
index f3dfbd09d3..6ff3d60383 100644
--- a/include/wx/dynarray.h
+++ b/include/wx/dynarray.h
@@ -90,11 +90,13 @@ public: \
void Alloc(size_t uiSize); \
void Shrink(); \
\
- size_t GetCount() const { return m_nCount; } \
- bool IsEmpty() const { return m_nCount == 0; } \
- size_t Count() const { return m_nCount; } \
+ size_t GetCount() const { return m_nCount; } \
+ void SetCount(size_t n, T defval = T(0)); \
+ bool IsEmpty() const { return m_nCount == 0; } \
+ size_t Count() const { return m_nCount; } \
\
typedef T base_type; \
+ \
protected: \
T& Item(size_t uiIndex) const \
{ wxASSERT( uiIndex < m_nCount ); return m_pItems[uiIndex]; } \
@@ -112,8 +114,8 @@ protected: \
void Sort(CMPFUNC fnCompare); \
\
private: \
- \
- void Grow(size_t nIncrement = 0); \
+ void Grow(size_t nIncrement = 0); \
+ bool Realloc(size_t nSize); \
\
size_t m_nSize, \
m_nCount; \
diff --git a/src/common/dynarray.cpp b/src/common/dynarray.cpp
index 4d0ee51d28..72284fcb73 100644
--- a/src/common/dynarray.cpp
+++ b/src/common/dynarray.cpp
@@ -106,6 +106,23 @@ name& name::operator=(const name& src) \
return *this; \
} \
\
+/* allocate new buffer of the given size and move our data to it */ \
+bool name::Realloc(size_t nSize) \
+{ \
+ T *pNew = new T[nSize]; \
+ /* only grow if allocation succeeded */ \
+ if ( !pNew ) \
+ return false; \
+ \
+ m_nSize = nSize; \
+ /* copy data to new location */ \
+ memcpy(pNew, m_pItems, m_nCount*sizeof(T)); \
+ delete [] m_pItems; \
+ m_pItems = pNew; \
+ \
+ return true; \
+} \
+ \
/* grow the array */ \
void name::Grow(size_t nIncrement) \
{ \
@@ -131,19 +148,34 @@ void name::Grow(size_t nIncrement) \
ndefIncrement = ARRAY_MAXSIZE_INCREMENT; \
if ( nIncrement < ndefIncrement ) \
nIncrement = ndefIncrement; \
- T *pNew = new T[m_nSize + nIncrement]; \
- /* only grow if allocation succeeded */ \
- if ( pNew ) { \
- m_nSize += nIncrement; \
- /* copy data to new location */ \
- memcpy(pNew, m_pItems, m_nCount*sizeof(T)); \
- delete [] m_pItems; \
- m_pItems = pNew; \
- } \
+ Realloc(m_nSize + nIncrement); \
} \
} \
} \
\
+/* make sure that the array has at least count elements */ \
+void name::SetCount(size_t count, T defval) \
+{ \
+ if ( m_nSize < count ) \
+ { \
+ /* need to realloc memory: don't overallocate it here as if */ \
+ /* SetCount() is called, it probably means that the caller */ \
+ /* knows in advance how many elements there will be in the */ \
+ /* array and so it won't be necessary to realloc it later */ \
+ if ( !Realloc(count) ) \
+ { \
+ /* out of memory -- what can we do? */ \
+ return; \
+ } \
+ } \
+ \
+ /* add new elements if we extend the array */ \
+ while ( m_nCount < count ) \
+ { \
+ m_pItems[m_nCount++] = defval; \
+ } \
+} \
+ \
/* dtor */ \
name::~name() \
{ \
--
2.47.2