c++ - 将指向字符矩阵的指针传递给 C++ 中的构造函数的问题
问题描述
我正在为使用 arduino 和按钮矩阵制作的键盘开发定制软件。我创建了一个 CustomKeyboard 类，其中包含与键盘相关的所有数据。它看起来像这样：
#define MAX_NROWS 10
#define MAX_NCOLS 30
#define MAX_NLAYERS 10
#define MAX_PRESSED_KEYS 7
#define KEY_ID_LENGTH 8
class CustomKeyboard{
public:
typedef void (*writeFunction) (CustomKeyboard *keyboard, char const *text);
int z = 0;
int cols[MAX_NCOLS];
int rows[MAX_NROWS];
int ncols, nrows, nlayers;
int stateMatrix[MAX_NROWS][MAX_NCOLS];
int maxPressedKeys = MAX_PRESSED_KEYS;
int pressKeysCoordinates[MAX_PRESSED_KEYS][2];
int holdKeysCoordinates[MAX_PRESSED_KEYS][2];
int releaseKeysCoordinates[MAX_PRESSED_KEYS][2];
char layout[MAX_NLAYERS][MAX_NROWS][MAX_NCOLS][KEY_ID_LENGTH];
writeFunction pressFunctions[MAX_NLAYERS][MAX_NROWS][MAX_NCOLS];
writeFunction releaseFunctions[MAX_NLAYERS][MAX_NROWS][MAX_NCOLS];
CustomKeyboard(
int const cols[], int const ncols, int const rows[], int const nrows, int const nlayers,
char const layout[2][5][15][8], writeFunction const pressFunctions[2][5][15], writeFunction const releaseFunctions[2][5][15]){
this->nlayers = nlayers;
// cols
this->ncols = ncols;
memset(this->cols, -1, MAX_NCOLS * sizeof(int));
memcpy(this->cols, cols, this->ncols * sizeof(int));
for(int i = 0; i< this->ncols; i++) { pinMode(this->cols[i], OUTPUT); digitalWrite(this->cols[0], LOW); }
// rows
this->nrows = nrows;
memset(this->rows, -1, MAX_NROWS * sizeof(int));
memcpy(this->rows, rows, this->nrows * sizeof(int));
for(int i = 0; i< this->nrows; i++) { pinMode(this->rows[i], INPUT_PULLDOWN); }
// stateMatrix
memset(stateMatrix, -1, sizeof(stateMatrix));
for(int i = 0; i < this->nrows; i++){
for(int j = 0; j < this->ncols; j++){
this->stateMatrix[i][j] = 0;
}
}
// layout and functions
for(int i = 0; i < this->nlayers; i++){
for(int j = 0; j < this->nrows; j++){
for(int k = 0; k < this->ncols; k++){
strcpy(this->layout[i][j][k],layout[i][j][k]);
this->pressFunctions[i][j][k] = pressFunctions[i][j][k];
this->releaseFunctions[i][j][k] = releaseFunctions[i][j][k];
}
}
}
}
void updateStateMatrix(){
// 0:idle 1:press 2:hold 3:release
int pressKeyCounter = 0;
memset(this->pressKeysCoordinates, -1, sizeof(pressKeysCoordinates));
int holdKeyCounter = 0;
memset(this->holdKeysCoordinates, -1, sizeof(holdKeysCoordinates));
int releaseKeyCounter = 0;
memset(this->releaseKeysCoordinates, -1, sizeof(releaseKeysCoordinates));
for (int icol = 0; icol< this->ncols; icol++){
digitalWrite(this->cols[icol], HIGH);
for (int irow = 0; irow< this->nrows; irow++){
if(digitalRead(this->rows[irow]) == 1){
if(this->stateMatrix[irow][icol] == 0){
// PRESS
this->pressKeysCoordinates[pressKeyCounter][0] = irow;
this->pressKeysCoordinates[pressKeyCounter][1] = icol;
pressKeyCounter++;
this->stateMatrix[irow][icol] = 1;
}else{
// HOLD
this->holdKeysCoordinates[holdKeyCounter][0] = irow;
this->holdKeysCoordinates[holdKeyCounter][1] = icol;
holdKeyCounter++;
this->stateMatrix[irow][icol] = 2;
}
}else{
if(this->stateMatrix[irow][icol] == 1 || this->stateMatrix[irow][icol] == 2 ){
// RELEASE
this->releaseKeysCoordinates[releaseKeyCounter][0] = irow;
this->releaseKeysCoordinates[releaseKeyCounter][1] = icol;
releaseKeyCounter++;
this->stateMatrix[irow][icol] = 3;
}else{
//IDLE
this->stateMatrix[irow][icol] = 0;
}
}
}
digitalWrite(cols[icol], LOW);
delay(1); // TODO: no entiendo porque esto es necesario
}
}
void execFunctions(){
for (int i = 0; i < this->maxPressedKeys; i++){
if(pressKeysCoordinates[i][0] != -1){
int row = pressKeysCoordinates[i][0];
int column = pressKeysCoordinates[i][1];
char *text = layout[this->z][row][column];
writeFunction function= pressFunctions[this->z][row][column];
function(this, text);
}
if(releaseKeysCoordinates[i][0] != -1){
int row = releaseKeysCoordinates[i][0];
int column = releaseKeysCoordinates[i][1];
char *text = layout[this->z][row][column];
writeFunction function= releaseFunctions[this->z][row][column];
function(this, text);
}
}
}
}
由于我使用的是 arduino，为了避免动态内存分配，我决定使用一些较大的值来创建矩阵（MAX_NROWS、MAX_NCOLS 等），然后我将使用我需要的空间。这种方法似乎工作正常，但我有一个问题。我不知道我将传递给类的构造函数的矩阵的大小。正如您在构造函数中看到的那样，我使用了值 2,5 和 15，因为这些是我的键盘矩阵的测量值。
CustomKeyboard(
int const cols[], int const ncols, int const rows[], int const nrows, int const nlayers,
char const layout[2][5][15][8], writeFunction const pressFunctions[2][5][15], writeFunction const releaseFunctions[2][5][15])
我在测试中通过的矩阵是：
char const layout[nlayers][nrows][ncols][KEY_ID_LENGTH] = {
{
{"`" , "1" , "2" , "3" , "4" , "5" , "_" , "_" , "6" , "7" , "8" , "9" , "0" , "-" , "=" },
{"caps" , "q" , "w" , "e" , "r" , "t" , "_" , "_" , "y" , "u" , "i" , "o" , "p" , "[" , "]" },
{"tab" , "a" , "s" , "d" , "f" , "g" , "_" , "_" , "h" , "j" , "k" , "l" , ";" , "'" , "\\" },
{"shift", "z" , "x" , "c" , "v" , "b" , "_" , "_" , "n" , "m" , "," , "." , "/" , "_" , "_" },
{"ctrl" , "mod" , "_" , "_" , "_" , "_" , "-" , "_" , "_" , "_" , "_" , "_" , "_" , "_" , "_" }
},{
{"2A1", "2A2", "2A3", "2A4", "2A5", "2A6", "2A7", "2A8", "2A9", "2A10", "2A11", "2A12", "2A13", "2A14", "2A15"},
{"2B1", "2B2", "2B3", "2B4", "2B5", "2B6", "2B7", "2B8", "2B9", "2B10", "2B11", "2B12", "2B13", "2B14", "2B15"},
{"2C1", "2C2", "2C3", "2C4", "2C5", "2C6", "2C7", "2C8", "2C9", "2C10", "2C11", "2C12", "2C13", "2C14", "2C15"},
{"2D1", "2D2", "2D3", "2D4", "2D5", "2D6", "2D7", "2D8", "2D9", "2D10", "2D11", "2D12", "2D13", "2D14", "2D15"},
{"2E1", "2E2", "2E3", "2E4", "2E5", "2E6", "2E7", "2E8", "2E9", "2E10", "2E11", "2E12", "2E13", "2E14", "2E15"}
}
};
CustomKeyboard::writeFunction const pressFunctions[nlayers][nrows][ncols]= {
{
{_______, WRITE__, WRITE__, WRITE__, WRITE__, WRITE__, LAYER_1, _______, WRITE__, WRITE__, WRITE__, WRITE__, WRITE__, WRITE__, WRITE__},
{_______, WRITE__, WRITE__, WRITE__, WRITE__, WRITE__, _______, _______, WRITE__, WRITE__, WRITE__, WRITE__, WRITE__, WRITE__, WRITE__},
{_______, WRITE__, WRITE__, WRITE__, WRITE__, WRITE__, _______, _______, WRITE__, WRITE__, WRITE__, WRITE__, WRITE__, WRITE__, WRITE__},
{P_SHIFT, WRITE__, WRITE__, WRITE__, WRITE__, WRITE__, _______, _______, WRITE__, WRITE__, WRITE__, WRITE__, WRITE__, WRITE__, WRITE__},
{_______, _______, _______, _______, _______, SPACE__, _______, _______, DEL____, P_ALT__, _______, _______, _______, _______, _______}
},{
{_______, TEST___, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______},
{_______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______},
{_______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______},
{_______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______},
{_______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______}
}
};
CustomKeyboard::writeFunction const releaseFunctions[nlayers][nrows][ncols]= {
{
{_______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______},
{_______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______},
{_______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______},
{R_SHIFT, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______},
{_______, _______, _______, _______, _______, _______, _______, _______, _______, R_ALT__, _______, _______, _______, _______, _______}
},{
{_______, _______, _______, _______, _______, _______, LAYER_0, _______, _______, _______, _______, _______, _______, _______, _______},
{_______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______},
{_______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______},
{_______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______},
{_______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______, _______}
}
};
我认为将指针传递给矩阵而不是副本会更有意义，因为这样我不需要在构造函数中设置大小，并且可以避免使用不必要的内存。问题是我不知道该怎么做。我已经尝试了所有想到的东西。
例如，矩阵layout，因为它是一个数组（1）的数组（2）的数组（3）的数组（4）的字符我想我应该写char**** const layout在构造函数中，但这似乎不起作用. 错误如下所示：
error: no matching function for call to 'CustomKeyboard::CustomKeyboard(const int [15], const int&, const int [5], const int&, const int&, const char (*)[2][5][15][8], void (* const [2][5][15])(CustomKeyboard*, const char*), void (* const [2][5][15])(CustomKeyboard*, const char*))'
我确信这个问题是因为我没有正确理解一些基本概念。
我还读到，当您将数组作为参数传递给函数时（我想构造函数也是如此），它会衰减为指向第一个元素的指针，所以当我调用构造函数时，它应该是相同的，对吧?
解决方案
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