零知开源——STM32F4实现ILI9486显示屏UI界面系列教程（一）：电子书阅读器功能

本教程将详细介绍如何在零知增强板上使用3.5寸ILI9486显示屏实现电子书阅读器功能。我们将使用LVGL库构建用户界面，并实现翻页、进度显示等核心功能。

目录

一、硬件连接

二、软件UI组件实现

三、零知IDE配置

四、演示效果

五、常见问题解决

六、总结与扩展

一、硬件连接

1.1 硬件组件清单

1.2 连接方式

零知增强板设计有专门的显示屏接口，3.5寸ILI9486显示屏可直接插入增强板，无需额外连线

电子书阅读器界面效果图：

二、软件UI组件实现

2.1 核心数据结构

static const char* ebook_content[] = {
    "Embedded Systems Fundamentals\n\n"
    "Embedded systems are specialized computing systems that perform dedicated functions.",
    "Microcontroller Architecture\n\n"
    "Microcontrollers (MCUs) contain a processor core, memory, and programmable I/O peripherals.",
    "Real-Time Operating Systems\n\n"
    "RTOS provides deterministic timing behavior for embedded applications.",
    "Communication Protocols\n\n"
    "Wired: UART, SPI, I2C, CAN\nWireless: BLE, Wi-Fi, LoRaWAN",
    "Development Lifecycle\n\n"
    "Stages: Requirements, Design, Implementation, Testing, Deployment"
};

static const uint8_t ebook_page_count = sizeof(ebook_content) / sizeof(ebook_content[0]);

// 电子书翻页事件回调
static void ebook_prev_event_cb(lv_obj_t* btn, lv_event_t event);
static void ebook_next_event_cb(lv_obj_t* btn, lv_event_t event);

typedef struct {
    uint8_t current_page;
    uint8_t total_pages;
    bool is_english;
    lv_point_t touch_start;  // 触摸起始点
    lv_obj_t* page_label;
    lv_obj_t* progress_label;
    lv_obj_t* btn_translate;
} EBookState;

2.2 触摸事件处理 

// 声明全局ebook_state变量
static EBookState ebook_state;

// 3. 完全兼容的触摸事件处理（替代手势事件）
static void ebook_touch_event_cb(lv_obj_t* obj, lv_event_t event) {
    static lv_point_t touch_start;
    static uint32_t touch_time;
    
    switch(event) {
        case LV_EVENT_PRESSED: {
            lv_indev_t* indev = lv_indev_get_act();
            if(indev) {
                lv_indev_get_point(indev, &touch_start);
                touch_time = lv_tick_get();
            }
            break;
        }
        case LV_EVENT_RELEASED: {
            lv_indev_t* indev = lv_indev_get_act();
            lv_point_t touch_end;
            if(indev) {
                lv_indev_get_point(indev, &touch_end);
                
                // 计算滑动距离和时间
                lv_coord_t dx = touch_end.x - touch_start.x;
                uint32_t duration = lv_tick_elaps(touch_time);
                
                // 判断有效滑动 (水平移动>30像素且时间<300ms)
                if(abs(dx) > 30 && duration < 300) {
                    if(dx > 0) {
                        // 向右滑动：上一页
                        if(ebook_state.current_page > 0) {
                            ebook_prev_event_cb(NULL, LV_EVENT_SHORT_CLICKED);
                        }
                    } else {
                        // 向左滑动：下一页
                        if(ebook_state.current_page < ebook_state.total_pages - 1) {
                            ebook_next_event_cb(NULL, LV_EVENT_SHORT_CLICKED);
                        }
                    }
                }
            }
            break;
        }
    }
}

// 更新电子书显示
static void update_ebook_display() {
    // 重置位置避免动画残留
    lv_obj_set_x(ebook_state.page_label, 0);
    lv_label_set_text(ebook_state.page_label, ebook_content[ebook_state.current_page]);
    
    char progress[16];
    snprintf(progress, sizeof(progress), "%d/%d", ebook_state.current_page + 1, ebook_state.total_pages);
    lv_label_set_text(ebook_state.progress_label, progress);
}

 2.3 初始化界面

void show_app_book() {
    lv_obj_t* win = create_app_win("EBook Reader");
    lv_coord_t hres = lv_disp_get_hor_res(NULL);
    lv_coord_t vres = lv_disp_get_ver_res(NULL);
    
    // 初始化电子书状态
    ebook_state.current_page = 0;
    ebook_state.total_pages = ebook_page_count;
    ebook_state.is_english = true; // 默认英文
    ebook_state.touch_start.x = 0;
    ebook_state.touch_start.y = 0;
    
    // 创建内容容器（支持触摸检测）
    lv_obj_t* content_cont = lv_cont_create(win, NULL);
    lv_obj_set_size(content_cont, hres - 40, vres - 100);
    lv_obj_align(content_cont, NULL, LV_ALIGN_IN_TOP_MID, 0, 20);
    // lv_obj_set_gesture_parent(content_cont, true);
    lv_obj_set_event_cb(content_cont, ebook_touch_event_cb);
    
    // 创建页面标签
    ebook_state.page_label = lv_label_create(content_cont, NULL);
    lv_obj_set_width(ebook_state.page_label, lv_obj_get_width(content_cont) - 20);
    lv_label_set_long_mode(ebook_state.page_label, LV_LABEL_LONG_EXPAND);
    lv_label_set_align(ebook_state.page_label, LV_LABEL_ALIGN_LEFT);
    lv_obj_set_width(ebook_state.page_label, lv_obj_get_width(content_cont) - 40); // 增加一些边距
    lv_label_set_text(ebook_state.page_label, "");
    lv_obj_align(ebook_state.page_label, NULL, LV_ALIGN_CENTER, 0, 0);
    
    // 创建进度标签
    ebook_state.progress_label = lv_label_create(win, NULL);
    lv_obj_align(ebook_state.progress_label, NULL, LV_ALIGN_IN_BOTTOM_MID, 0, -30);
    lv_label_set_text(ebook_state.progress_label, "0/0");
    
    // 初始显示
    update_ebook_display();
}

 2.4 翻页功能实现

// 翻页动画函数 (兼容旧版LVGL)
static void ebook_page_anim(lv_obj_t* label, lv_coord_t start, lv_coord_t end) {
    lv_anim_t a;
    lv_anim_init(&a);
    // lv_anim_set_var(&a, label);
    lv_anim_set_values(&a, start, end);
    lv_anim_set_time(&a, 300, 0);  // 兼容旧版API：设置持续时间和延迟
    lv_anim_set_exec_cb(&a, label, (lv_anim_exec_xcb_t)lv_obj_set_x);  // 兼容旧版API
    lv_anim_create(&a);
}

// 上一页事件
static void ebook_prev_event_cb(lv_obj_t* btn, lv_event_t event) {
    if(event == LV_EVENT_SHORT_CLICKED) {
        if(ebook_state.current_page > 0) {
            // 先设置新内容再动画
            ebook_state.current_page--;
            update_ebook_display();
            
            // 从左侧滑入动画
            lv_obj_set_x(ebook_state.page_label, -lv_obj_get_width(lv_obj_get_parent(ebook_state.page_label)));
            ebook_page_anim(ebook_state.page_label, 
                           -lv_obj_get_width(lv_obj_get_parent(ebook_state.page_label)), 
                           0);
        }
    }
}

// 下一页事件
static void ebook_next_event_cb(lv_obj_t* btn, lv_event_t event) {
    if(event == LV_EVENT_SHORT_CLICKED) {
        if(ebook_state.current_page < ebook_state.total_pages - 1) {
            ebook_state.current_page++;
            update_ebook_display();
            
            // 从右侧滑入动画
            lv_obj_set_x(ebook_state.page_label, lv_obj_get_width(lv_obj_get_parent(ebook_state.page_label)));
            ebook_page_anim(ebook_state.page_label, 
                           lv_obj_get_width(lv_obj_get_parent(ebook_state.page_label)), 
                           0);
        }
    }
}

2.5 功能说明

支持左右滑动翻页，滑动距离大于30像素且时间小于300ms时触发

屏幕两侧的箭头按钮提供物理翻页功能

使用LVGL动画实现平滑的翻页效果

底部显示当前页码和总页数

使用英文字体内容显示(中文字体需要进一步优化取模)

三、零知IDE配置

3.1 项目设置

打开零知IDE，创建新项目

选择正确的开发板型号（零知增强板）

添加以下库依赖：

• LVGL

• ILI9486驱动

• XPT2046触摸驱动

3.2 LCD屏幕驱动和初始化

/* 与LCD驱动关联 */
void my_disp_flush(lv_disp_drv_t *disp, const lv_area_t *area, lv_color_t *color_p)
{
         
        u16 height,width;
        u16 i,j;
        width=area->x2 - area->x1+1;                         //得到填充的宽度
        height=area->y2 - area->y1+1;                        //高度
        for(i=0;i<height;i++)
        {
                LCD_SetCursor(area->x1,area->y1+i);           //设置光标位置
                LCD_WriteRAM_Prepare();     //开始写入GRAM
                for(j=0;j<width;j++)
                {
                        LCD_TYPE->LCD_RAM=color_p->full;//写入数据
                        color_p++;
                }
        }
         
        lv_disp_flush_ready(disp); 
}

/* 中断 ms */
static void lv_tick_handler(HardwareTimer*)
{
        lv_tick_inc(LVGL_TICK_PERIOD);
}

void lvgl_setup()
{
        lv_init();
         
        lv_disp_buf_init(&disp_buf, buf, NULL, LV_HOR_RES_MAX * 10);
         
        
        lv_disp_drv_t disp_drv;
        lv_disp_drv_init(&disp_drv);
        disp_drv.hor_res = LV_HOR_RES_MAX;
        disp_drv.ver_res = LV_VER_RES_MAX;
        disp_drv.flush_cb = my_disp_flush;
        disp_drv.buffer = &disp_buf;
        lv_disp_drv_register(&disp_drv);
         
         
       
        lv_indev_drv_t indev_drv;
        lv_indev_drv_init(&indev_drv);
        indev_drv.type = LV_INDEV_TYPE_POINTER;
        indev_drv.read_cb = my_touchpad_read;
        lv_indev_drv_register(&indev_drv);
         
        
        MyTim = new HardwareTimer(TIM2);
        MyTim->setMode(2, TIMER_OUTPUT_COMPARE);   
        MyTim->setOverflow(1000/LVGL_TICK_PERIOD, HERTZ_FORMAT); 
        MyTim->attachInterrupt(lv_tick_handler);
        MyTim->resume();
}

四、演示效果

4.1 功能演示

打开电子书应用，显示第一页内容

向右滑动：切换到上一页内容

向左滑动：切换到下一页内容

进度更新：底部页码随翻页自动更新

4.2 视频演示

4.3 性能指标

五、常见问题解决

5.1 触摸不灵敏

解决方案

• 检查触摸屏校准数据
• 增加触摸检测阈值

bool my_touchpad_read(lv_indev_drv_t * indev, lv_indev_data_t * data)
{
        static lv_coord_t last_x = 0;
        static lv_coord_t last_y = 0;
         
        
        data->state = ts.touched() ? LV_INDEV_STATE_PR : LV_INDEV_STATE_REL;
        if(data->state == LV_INDEV_STATE_PR){
                TS_Point p = ts.getPoint();
                 
               
                last_x = LV_HOR_RES-(p.y *LV_HOR_RES)/4095;       
                last_y = (p.x *LV_VER_RES)/4095;       
                 
                Serial.print("touched:");
                Serial.print(last_x);Serial.print(",");Serial.println(last_y);
        }
      
        data->point.x = last_x;
        data->point.y = last_y;
         
        return false; 
}

5.2 翻页卡顿

优化建议

• 减少页面内容长度
• 使用LVGL的局部刷新功能
• 优化动画参数

lv_anim_set_time(&a, 300, 0);  // 兼容旧版API：设置持续时间和延迟

六、总结与扩展

6.1 实现总结

本教程实现了电子书阅读器的核心功能：中文内容显示、触摸翻页、翻页动画效果、阅读进度显示

6.2 扩展建议

• 添加书签保存和跳转功能

• 实现字体大小切换

• 添加暗色主题保护视力

• 从SD卡加载电子书文件

6.3 下一步

在下一个系列教程中，我们将实现日历显示及切换