c++ - SDL2 键盘检测不起作用

Question

我尝试使用 sdl2 制作一个简单的游戏来处理键盘事件。但主要问题是，无论是在 Clion 嵌入式控制台还是在外部控制台中，我的程序都无法检测到任何事件，只有 SDL_AUDIODEVICEADDED 在程序启动时被捕获了两次。这是我的代码:

#include <iostream>
#include "include/SDL2/SDL_keyboard.h"
#include "include/SDL2/SDL_keycode.h"
#include "include/SDL2/SDL_scancode.h"

#include "include/SDL2/SDL.h"

using namespace std;

int main(int argc, char* argv []) {
    SDL_Event event;
    bool running = true;
    SDL_Init(SDL_INIT_EVERYTHING);
    int x, y;
    while(running){

        if(SDL_PollEvent(&event)){
            switch(event.type){
                case SDL_QUIT: running = false; break; 
                case SDL_KEYDOWN: 
                    switch(event.key.keysym.sym){ 
                        case SDLK_q: 
                            running = false;
                            break; 
                    }
                    break;

                case SDL_MOUSEBUTTONDOWN:
                    SDL_GetMouseState(&x, &y); 
                    cout << "[SDL_MOUSEBUTTONDOWN] " << "x = " << x << " y = " << y << "\n";
                    break;
                case SDL_MOUSEMOTION:
                    x = event.motion.x;
                    y = event.motion.y;
                    cout << "[SDL_MOUSEMOTION] " << "x = " << x << " y = " << y << "\n";
                    break;
            }
        }
    }
}

SDL_Init 返回 0。

Answer 1

您需要创建一个窗口。

键盘和鼠标事件取决于显示表面。只有窗口内的鼠标操作和窗口处于焦点时的键盘输入才会被捕获。毕竟，您不应该能够接收可能针对其他应用程序的输入。