用C语言写一个在lcd上触摸滚动条,
时间: 2023-05-14 13:07:27 浏览: 64
可以使用SDL库来实现在LCD上的触摸滚动条,以下是示例代码:
#include <SDL.h>
int main(int argc, char* argv[]) {
SDL_Init(SDL_INIT_VIDEO);
SDL_Window* window = SDL_CreateWindow("Touch Scrollbar", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, 640, 480, SDL_WINDOW_SHOWN);
SDL_Renderer* renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);
SDL_Rect scrollbar = { 580, 50, 20, 380 };
SDL_Rect thumb = { 580, 50, 20, 50 };
SDL_Event event;
int running = 1;
while (running) {
while (SDL_PollEvent(&event)) {
switch (event.type) {
case SDL_QUIT:
running = 0;
break;
case SDL_MOUSEBUTTONDOWN:
if (event.button.x >= thumb.x && event.button.x <= thumb.x + thumb.w && event.button.y >= thumb.y && event.button.y <= thumb.y + thumb.h) {
thumb.y = event.button.y - thumb.h / 2;
}
break;
case SDL_MOUSEBUTTONUP:
break;
case SDL_MOUSEMOTION:
if (event.motion.state & SDL_BUTTON(SDL_BUTTON_LEFT)) {
if (event.motion.y >= scrollbar.y && event.motion.y <= scrollbar.y + scrollbar.h - thumb.h) {
thumb.y = event.motion.y - thumb.h / 2;
}
}
break;
}
}
SDL_SetRenderDrawColor(renderer, 255, 255, 255, 255);
SDL_RenderClear(renderer);
SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);
SDL_RenderFillRect(renderer, &scrollbar);
SDL_SetRenderDrawColor(renderer, 128, 128, 128, 255);
SDL_RenderFillRect(renderer, &thumb);
SDL_RenderPresent(renderer);
}
SDL_DestroyRenderer(renderer);
SDL_DestroyWindow(window);
SDL_Quit();
return 0;
}
这段代码使用 SDL_Init() 函数初始化 SDL 库,创建一个窗口和渲染器,然后在窗口上绘制一个滚动条和滑块。在事件循环中,处理鼠标按下、鼠标移动和鼠标释放事件,以更新滑块的位置。最后,使用 SDL_DestroyRenderer() 和 SDL_DestroyWindow() 函数释放资源,退出程序。
注意:这只是一个示例代码,实际应用中需要根据具体的硬件平台和LCD屏幕的特性进行适当的修改。