LVGL btn组件

/*************************************************
 *
 *   file name:widget_line.c
 *   author   :momolyl@126.com
 *   date     :2024/06/17
 *   brief :移植LVGL，实现在屏幕上显示一个按钮，按钮上有一个标签，当用户通过触摸屏点击了该按钮，则显示一个新的屏幕对象
 *   note     :None
 *
 *   CopyRight (c) 2024    momolyl@126.com    All Right Reseverd
 *
 **************************************************/
#include "lvgl/lvgl.h"
#include "lvgl/demos/lv_demos.h"
#include "lv_drivers/display/fbdev.h"
#include "lv_drivers/indev/evdev.h"
#include <unistd.h>
#include <pthread.h>
#include <time.h>
#include <sys/time.h>

#define DISP_BUF_SIZE (8 * 1024 * 1024)
static void my_event_cb(lv_event_t * event)
{

    /*创建线条风格*/
    // 创建风格对象
    static lv_style_t style_line;
    // 对新创建的线条风格进行初始化
    lv_style_init(&style_line);
    // 设置线条宽度
    lv_style_set_line_width(&style_line, 8);
    // 设置线条颜色
    lv_style_set_line_color(&style_line, lv_palette_main(LV_PALETTE_PINK));
    // 设置线条端点是否为圆点
    lv_style_set_line_rounded(&style_line, true);

    /*虚线只能用于水平或垂直线条*/
    // lv_obj_set_style_line_dash_width(&style_line, 1, LV_PART_MAIN);//虚线显示的线条长度
    // lv_obj_set_style_line_dash_gap(&style_line, 1, LV_PART_MAIN);//虚线间隔的线条长度

    // 创建屏幕对象
    lv_obj_t * scr2 = lv_obj_create(NULL);

    // 创建线条对象
    lv_obj_t * line1 = lv_line_create(scr2);

    // 设置点数组
    static lv_point_t line_points[] = {{5, 5}, {70, 70}, {120, 10}, {180, 60}, {240, 10}};
    // 创建线条的连接点
    lv_line_set_points(line1, line_points, 5);

    // 是否反转y轴反向（默认y轴起点为上，即自上而下y值(纵坐标)增大；若选择反转，则y轴起点为下，即自下而上y值(纵坐标)增大）
    lv_line_set_y_invert(line1, true);

    // 设置线条风格
    lv_obj_add_style(line1, &style_line, 0);

    // 设置主体的位置（参照点为主体左上方的顶点）
    lv_obj_set_pos(line1, 100, 0);

    // 将创建好的线条主体添加到父对象上
    lv_obj_center(scr2);

    // 加载屏幕对象
    lv_scr_load(scr2);
}

int main(void)
{
    /*LittlevGL init*/
    lv_init(); // 初始化LVGL图形库

    /*Linux frame buffer device init*/
    fbdev_init();

    /*A small buffer for LittlevGL to draw the screen's content*/
    static lv_color_t buf[DISP_BUF_SIZE];

    /*Initialize a descriptor for the buffer*/
    static lv_disp_draw_buf_t disp_buf;
    lv_disp_draw_buf_init(&disp_buf, buf, NULL, DISP_BUF_SIZE);

    /*Initialize and register a display driver*/
    static lv_disp_drv_t disp_drv;
    lv_disp_drv_init(&disp_drv);
    disp_drv.draw_buf = &disp_buf;
    disp_drv.flush_cb = fbdev_flush;
    disp_drv.hor_res  = 800;
    disp_drv.ver_res  = 480;
    lv_disp_drv_register(&disp_drv);

    evdev_init();
    static lv_indev_drv_t indev_drv_1;
    lv_indev_drv_init(&indev_drv_1); /*Basic initialization*/
    indev_drv_1.type = LV_INDEV_TYPE_POINTER;

    /*This function will be called periodically (by the library) to get the mouse position and state*/
    indev_drv_1.read_cb      = evdev_read;
    lv_indev_t * mouse_indev = lv_indev_drv_register(&indev_drv_1);

    // 创建屏幕对象
    lv_obj_t * scr1 = lv_obj_create(NULL);
    // 创建按钮对象
    lv_obj_t * btn1 = lv_btn_create(scr1);

    lv_obj_set_pos(btn1, 375, 220); // 设置按钮的位置
    // 创建标签对象
    lv_obj_t * lab1 = lv_label_create(btn1);
    lv_label_set_text(lab1, "line"); // 设置标签内容

    // 加载屏幕对象
    lv_scr_load(scr1);

    lv_obj_add_event_cb(btn1, my_event_cb, LV_EVENT_CLICKED, NULL); /*分配一个事件回调*/

    /*Handle LitlevGL tasks (tickless mode)*/
    while(1) {
        lv_tick_inc(5);
        lv_timer_handler();
        usleep(5000);
    }

    return 0;
}