LVGL简介
相比较于老式的嵌入式UI界面设计方案，lvgl的优势在于：
LVGL官网链接：
LVGL源码
LVGL特性
/**
* @file lv_conf.h
* Configuration file for v8.3.0-dev
*/
/*
* Copy this file as `lv_conf.h`
* 1. simply next to the `lvgl` folder
* 2. or any other places and
* - define `LV_CONF_INCLUDE_SIMPLE`
* - add the path as include path
*/
/* clang-format off */
#if 0 /*Set it to "1" to enable content*/
#define ST7735S_WIDTH 128
#define ST7735S_HEIGHT 128
#define MY_DISP_HOR_RES 128
#define MY_DISP_VER_RES 128
#define LV_VER_RES_MAX 128
/**
* @file lv_port_disp_templ.c
*
*/
/*Copy this file as "lv_port_disp.c" and set this value to "1" to enable content */
#if 1
void lv_port_disp_init(void)
{
/*-------------------------
* Initialize your display
* -----------------------*/
disp_init();
/*-----------------------------
* Create a buffer for drawing
*----------------------------*/
/**
* LVGL requires a buffer where it internally draws the widgets.
* Later this buffer will passed to your display driver's `flush_cb` to copy its content to your display.
* The buffer has to be greater than 1 display row
*
* There are 3 buffering configurations:
* 1. Create ONE buffer:
* LVGL will draw the display's content here and writes it to your display
*
* 2. Create TWO buffer:
* LVGL will draw the display's content to a buffer and writes it your display.
* You should use DMA to write the buffer's content to the display.
* It will enable LVGL to draw the next part of the screen to the other buffer while
* the data is being sent form the first buffer. It makes rendering and flushing parallel.
*
* 3. Double buffering
* Set 2 screens sized buffers and set disp_drv.full_refresh = 1.
* This way LVGL will always provide the whole rendered screen in `flush_cb`
* and you only need to change the frame buffer's address.
*/
/* Example for 1) */
static lv_disp_draw_buf_t draw_buf_dsc_1;
static lv_color_t buf_1[MY_DISP_HOR_RES * 10]; /*A buffer for 10 rows*/
lv_disp_draw_buf_init(&draw_buf_dsc_1, buf_1, NULL, MY_DISP_HOR_RES * 10); /*Initialize the display buffer*/
// /* Example for 2) */
// static lv_disp_draw_buf_t draw_buf_dsc_2;
// static lv_color_t buf_2_1[MY_DISP_HOR_RES * 10]; /*A buffer for 10 rows*/
// static lv_color_t buf_2_2[MY_DISP_HOR_RES * 10]; /*An other buffer for 10 rows*/
// lv_disp_draw_buf_init(&draw_buf_dsc_2, buf_2_1, buf_2_2, MY_DISP_HOR_RES * 10); /*Initialize the display buffer*/
// /* Example for 3) also set disp_drv.full_refresh = 1 below*/
// static lv_disp_draw_buf_t draw_buf_dsc_3;
// static lv_color_t buf_3_1[MY_DISP_HOR_RES * MY_DISP_VER_RES]; /*A screen sized buffer*/
// static lv_color_t buf_3_2[MY_DISP_HOR_RES * MY_DISP_VER_RES]; /*Another screen sized buffer*/
// lv_disp_draw_buf_init(&draw_buf_dsc_3, buf_3_1, buf_3_2, MY_DISP_VER_RES * LV_VER_RES_MAX); /*Initialize the display buffer*/
/*-----------------------------------
* Register the display in LVGL
*----------------------------------*/
static lv_disp_drv_t disp_drv; /*Descriptor of a display driver*/
lv_disp_drv_init(&disp_drv); /*Basic initialization*/
/*Set up the functions to access to your display*/
/*Set the resolution of the display*/
disp_drv.hor_res = ST7735S_WIDTH;
disp_drv.ver_res = ST7735S_HEIGHT;
/*Used to copy the buffer's content to the display*/
disp_drv.flush_cb = disp_flush;
/*Set a display buffer*/
disp_drv.draw_buf = &draw_buf_dsc_1;
/*Required for Example 3)*/
//disp_drv.full_refresh = 1
/* Fill a memory array with a color if you have GPU.
* Note that, in lv_conf.h you can enable GPUs that has built-in support in LVGL.
* But if you have a different GPU you can use with this callback.*/
//disp_drv.gpu_fill_cb = gpu_fill;
/*Finally register the driver*/
lv_disp_drv_register(&disp_drv);
}
disp_drv.hor_res = ST7735S_WIDTH;
disp_drv.ver_res = ST7735S_HEIGHT;
disp_drv.flush_cb = disp_flush;
extern void LCD_DrawPoint(uint16_t x,uint16_t y,uint16_t color);
/*Flush the content of the internal buffer the specific area on the display
*You can use DMA or any hardware acceleration to do this operation in the background but
*'lv_disp_flush_ready()' has to be called when finished.*/
static void disp_flush(lv_disp_drv_t * disp_drv, const lv_area_t * area, lv_color_t * color_p)
{
/*The most simple case (but also the slowest) to put all pixels to the screen one-by-one*/
int32_t x;
int32_t y;
for(y = area->y1; y <= area->y2; y++) {
for(x = area->x1; x <= area->x2; x++) {
/*Put a pixel to the display. For example:*/
/*put_px(x, y, *color_p)*/
// 画点函数，例如常见的一些屏用的是16位颜色，你把16位数据输出到屏幕即可
LCD_DrawPoint(x, y, color_p->full);
color_p++;
}
}
// LCD_Fill(area->x1, area->y1, area->x2, area->y2, *((uint16_t *)color_p));
/*IMPORTANT!!!
*Inform the graphics library that you are ready with the flushing*/
lv_disp_flush_ready(disp_drv);
}
#if 1 /*Set it to "1" to enable content*/
#ifndef LV_CONF_H
#define LV_CONF_H
#include <stdint.h>
// 屏幕尺寸需要配置
#define MY_DISP_HOR_RES 128
#define MY_DISP_VER_RES 128
#define LV_VER_RES_MAX 128
/*====================
COLOR SETTINGS 颜色相关的配置
*====================*/
// 颜色的配置，这里我们使用 RGB565。所以配置为 16
/*Color depth: 1 (1 byte per pixel), 8 (RGB332), 16 (RGB565), 32 (ARGB8888)*/
#define LV_COLOR_DEPTH 16
/*Swap the 2 bytes of RGB565 color. Useful if the display has an 8-bit interface (e.g. SPI)*/
#define LV_COLOR_16_SWAP 0
/*Enable more complex drawing routines to manage screens transparency.
*Can be used if the UI is above another layer, e.g. an OSD menu or video player.
*Requires `LV_COLOR_DEPTH = 32` colors and the screen's `bg_opa` should be set to non LV_OPA_COVER value*/
#define LV_COLOR_SCREEN_TRANSP 0
/* Adjust color mix functions rounding. GPUs might calculate color mix (blending) differently.
* 0: round down, 64: round up from x.75, 128: round up from half, 192: round up from x.25, 254: round up */
#define LV_COLOR_MIX_ROUND_OFS (LV_COLOR_DEPTH == 32 ? 0: 128)
/*Images pixels with this color will not be drawn if they are chroma keyed)*/
#define LV_COLOR_CHROMA_KEY lv_color_hex(0x00ff00) /*pure green*/
#if 1 /*Set it to "1" to enable content*/
/*=========================
MEMORY SETTINGS 内存相关的配置，如果没有定义 LV_MEM_CUSTOM，那么代表动态内存分配释放，使用 LVGL 那套内存管理算法
默认情况下 LVGL 使用 TLSF 内存管理算法，LV_MEM_SIZE 指定了 LVGL 管理的内存大小；这个需要配置
*=========================*/
/*1: use custom malloc/free, 0: use the built-in `lv_mem_alloc()` and `lv_mem_free()`*/
#define LV_MEM_CUSTOM 0
#if LV_MEM_CUSTOM == 0
/*Size of the memory available for `lv_mem_alloc()` in bytes (>= 2kB)*/
// 此内存用于 LVGL 的动态申请/释放内存，这里我们配置的 48KB 的全局数组给 LVGL 使用
#define LV_MEM_SIZE (48U * 1024U) /*[bytes]*/
/*Set an address for the memory pool instead of allocating it as a normal array. Can be in external SRAM too.*/
#define LV_MEM_ADR 0 /*0: unused*/
/*Instead of an address give a memory allocator that will be called to get a memory pool for LVGL. E.g. my_malloc*/
#if LV_MEM_ADR == 0
//#define LV_MEM_POOL_INCLUDE your_alloc_library /* Uncomment if using an external allocator*/
//#define LV_MEM_POOL_ALLOC your_alloc /* Uncomment if using an external allocator*/
#endif
#else /*LV_MEM_CUSTOM*/
#define LV_MEM_CUSTOM_INCLUDE <stdlib.h> /*Header for the dynamic memory function*/
#define LV_MEM_CUSTOM_ALLOC malloc
#define LV_MEM_CUSTOM_FREE free
#define LV_MEM_CUSTOM_REALLOC realloc
#endif /*LV_MEM_CUSTOM*/
/*Number of the intermediate memory buffer used during rendering and other internal processing mechanisms.
*You will see an error log message if there wasn't enough buffers. */
// 用于渲染和 LVGL 内部处理机制的 buffer 个数，如果配置不够的话，LVGL 会打印 ERROR 信息
// 这个其实是一个 lv_mem_buf_arr_t[LV_MEM_BUF_MAX_NUM] 结构的数组个数；
#define LV_MEM_BUF_MAX_NUM 16
/*Use the standard `memcpy` and `memset` instead of LVGL's own functions. (Might or might not be faster).*/
#define LV_MEMCPY_MEMSET_STD 0
/*====================
HAL SETTINGS HAL 层的配置
*====================*/
/*Default display refresh period. LVG will redraw changed areas with this period time*/
// 这个参数决定了多久处理一起屏幕刷新，默认情况是 30ms
#define LV_DISP_DEF_REFR_PERIOD 30 /*[ms]*/
/*Input device read period in milliseconds*/
// 这个参数决定了多久处理一起input，默认情况是 30ms
#define LV_INDEV_DEF_READ_PERIOD 30 /*[ms]*/
/*Use a custom tick source that tells the elapsed time in milliseconds.
*It removes the need to manually update the tick with `lv_tick_inc()`)*/
#define LV_TICK_CUSTOM 0
#if LV_TICK_CUSTOM
#define LV_TICK_CUSTOM_INCLUDE "Arduino.h" /*Header for the system time function*/
#define LV_TICK_CUSTOM_SYS_TIME_EXPR (millis()) /*Expression evaluating to current system time in ms*/
#endif /*LV_TICK_CUSTOM*/
/*Default Dot Per Inch. Used to initialize default sizes such as widgets sized, style paddings.
*(Not so important, you can adjust it to modify default sizes and spaces)*/
/*
* LV_DPI_DEF 注意这里，虽然LVGL的作者说这个没这么重要，但他会严重影响到LVGL的动画效果
* 你应该进行DPI的手动计算，例如128x128分辨率1.44英寸的屏幕，那么 DPI = ((√128*128) / 1.44) ≈ 89
*/
#define LV_DPI_DEF 89 /*[px/inch]*/
/*-------------
* Others
*-----------*/
/*1: Show CPU usage and FPS count*/
#define LV_USE_PERF_MONITOR 1
#if LV_USE_PERF_MONITOR
#define LV_USE_PERF_MONITOR_POS LV_ALIGN_BOTTOM_RIGHT
#endif
/*1: Show the used memory and the memory fragmentation
* Requires LV_MEM_CUSTOM = 0*/
#define LV_USE_MEM_MONITOR 0
#if LV_USE_MEM_MONITOR
#define LV_USE_MEM_MONITOR_POS LV_ALIGN_BOTTOM_LEFT
#endif
/*1: Draw random colored rectangles over the redrawn areas*/
#define LV_USE_REFR_DEBUG 0
/*Change the built in (v)snprintf functions*/
#define LV_SPRINTF_CUSTOM 0
#if LV_SPRINTF_CUSTOM
#define LV_SPRINTF_INCLUDE <stdio.h>
#define lv_snprintf snprintf
#define lv_vsnprintf vsnprintf
#else /*LV_SPRINTF_CUSTOM*/
#define LV_SPRINTF_USE_FLOAT 0
#endif /*LV_SPRINTF_CUSTOM*/
#define LV_USE_USER_DATA 1
/*Garbage Collector settings
*Used if lvgl is bound to higher level language and the memory is managed by that language*/
#define LV_ENABLE_GC 0
#if LV_ENABLE_GC != 0
#define LV_GC_INCLUDE "gc.h" /*Include Garbage Collector related things*/
#endif /*LV_ENABLE_GC*/
/*=====================
* COMPILER SETTINGS
*====================*/
/*For big endian systems set to 1*/
#define LV_BIG_ENDIAN_SYSTEM 0
/*Define a custom attribute to `lv_tick_inc` function*/
#define LV_ATTRIBUTE_TICK_INC
/*Define a custom attribute to `lv_timer_handler` function*/
#define LV_ATTRIBUTE_TIMER_HANDLER
/*Define a custom attribute to `lv_disp_flush_ready` function*/
#define LV_ATTRIBUTE_FLUSH_READY
/*Required alignment size for buffers*/
#define LV_ATTRIBUTE_MEM_ALIGN_SIZE 1
/*Will be added where memories needs to be aligned (with -Os data might not be aligned to boundary by default).
* E.g. __attribute__((aligned(4)))*/
#define LV_ATTRIBUTE_MEM_ALIGN
/*Attribute to mark large constant arrays for example font's bitmaps*/
#define LV_ATTRIBUTE_LARGE_CONST
/*Compiler prefix for a big array declaration in RAM*/
#define LV_ATTRIBUTE_LARGE_RAM_ARRAY
/*Place performance critical functions into a faster memory (e.g RAM)*/
#define LV_ATTRIBUTE_FAST_MEM
/*Prefix variables that are used in GPU accelerated operations, often these need to be placed in RAM sections that are DMA accessible*/
#define LV_ATTRIBUTE_DMA
/*Export integer constant to binding. This macro is used with constants in the form of LV_<CONST> that
*should also appear on LVGL binding API such as Micropython.*/
#define LV_EXPORT_CONST_INT(int_value) struct _silence_gcc_warning /*The default value just prevents GCC warning*/
/*Extend the default -32k..32k coordinate range to -4M..4M by using int32_t for coordinates instead of int16_t*/
#define LV_USE_LARGE_COORD 0
/*==================
* WIDGET USAGE
*================*/
/*Documentation of the widgets: https://docs.lvgl.io/latest/en/html/widgets/index.html*/
#define LV_USE_ARC 1
#define LV_USE_ANIMIMG 1
#define LV_USE_BAR 1
#define LV_USE_BTN 1
#define LV_USE_BTNMATRIX 1
#define LV_USE_CANVAS 1
#define LV_USE_CHECKBOX 1
#define LV_USE_DROPDOWN 1 /*Requires: lv_label*/
#define LV_USE_IMG 1 /*Requires: lv_label*/
#define LV_USE_LABEL 1
#if LV_USE_LABEL
#define LV_LABEL_TEXT_SELECTION 1 /*Enable selecting text of the label*/
#define LV_LABEL_LONG_TXT_HINT 1 /*Store some extra info in labels to speed up drawing of very long texts*/
#endif
#define LV_USE_LINE 1
#define LV_USE_ROLLER 1 /*Requires: lv_label*/
#if LV_USE_ROLLER
#define LV_ROLLER_INF_PAGES 7 /*Number of extra "pages" when the roller is infinite*/
#endif
#define LV_USE_SLIDER 1 /*Requires: lv_bar*/
#define LV_USE_SWITCH 1
#define LV_USE_TEXTAREA 1 /*Requires: lv_label*/
#if LV_USE_TEXTAREA != 0
#define LV_TEXTAREA_DEF_PWD_SHOW_TIME 1500 /*ms*/
#endif
#define LV_USE_TABLE 1
/*==================
* EXTRA COMPONENTS
*==================*/
/*-----------
* Widgets
*----------*/
#define LV_USE_CALENDAR 1
#if LV_USE_CALENDAR
#define LV_CALENDAR_WEEK_STARTS_MONDAY 0
#if LV_CALENDAR_WEEK_STARTS_MONDAY
#define LV_CALENDAR_DEFAULT_DAY_NAMES {"Mo", "Tu", "We", "Th", "Fr", "Sa", "Su"}
#else
#define LV_CALENDAR_DEFAULT_DAY_NAMES {"Su", "Mo", "Tu", "We", "Th", "Fr", "Sa"}
#endif
#define LV_CALENDAR_DEFAULT_MONTH_NAMES {"January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"}
#define LV_USE_CALENDAR_HEADER_ARROW 1
#define LV_USE_CALENDAR_HEADER_DROPDOWN 1
#endif /*LV_USE_CALENDAR*/
#define LV_USE_CHART 1
#define LV_USE_COLORWHEEL 1
#define LV_USE_IMGBTN 1
#define LV_USE_KEYBOARD 1
#define LV_USE_LED 1
#define LV_USE_LIST 1
#define LV_USE_MENU 1
#define LV_USE_METER 1
#define LV_USE_MSGBOX 1
#define LV_USE_SPINBOX 1
#define LV_USE_SPINNER 1
#define LV_USE_TABVIEW 1
#define LV_USE_TILEVIEW 1
#define LV_USE_WIN 1
#define LV_USE_SPAN 1
#if LV_USE_SPAN
/*A line text can contain maximum num of span descriptor */
#define LV_SPAN_SNIPPET_STACK_SIZE 64
#endif
/*===================
* DEMO USAGE
====================*/
/*Show some widget. It might be required to increase `LV_MEM_SIZE` */
#define LV_USE_DEMO_WIDGETS 0
#if LV_USE_DEMO_WIDGETS
#define LV_DEMO_WIDGETS_SLIDESHOW 0
#endif
/*Demonstrate the usage of encoder and keyboard*/
#define LV_USE_DEMO_KEYPAD_AND_ENCODER 0
/*Benchmark your system*/
#define LV_USE_DEMO_BENCHMARK 1
/*Stress test for LVGL*/
#define LV_USE_DEMO_STRESS 0
/*Music player demo*/
#define LV_USE_DEMO_MUSIC 0
#if LV_USE_DEMO_MUSIC
# define LV_DEMO_MUSIC_SQUARE 0
# define LV_DEMO_MUSIC_LANDSCAPE 0
# define LV_DEMO_MUSIC_ROUND 0
# define LV_DEMO_MUSIC_LARGE 0
# define LV_DEMO_MUSIC_AUTO_PLAY 0
#endif
/**
* @brief This function handles SysTick Handler.
* @param None
* @retval None
*/
void SysTick_Handler(void)
{
lv_tick_inc(1);
}
while(1)
{
lv_timer_handler();
LVGL_Delay();
}
void LVGL_CentralButton(void)
{
lv_obj_t *btn = lv_btn_create(lv_scr_act());
lv_obj_align(btn, LV_ALIGN_CENTER, 0, 0);
lv_obj_set_height(btn, 30);
lv_obj_t *label;
label = lv_label_create(btn);
lv_obj_align(label, LV_ALIGN_CENTER, 0, 0);
lv_label_set_text(label, "LVGL");
static lv_style_t style_btn;
lv_style_init(&style_btn);
lv_style_set_radius(&style_btn, 10);
lv_style_set_border_color(&style_btn, lv_color_white());
lv_style_set_border_opa(&style_btn, LV_OPA_30);
lv_obj_add_style(btn, &style_btn, LV_STATE_DEFAULT);
}
void LVGL_Init(void)
{
lv_init(); // lvgl初始化，如果这个没有初始化，那么下面的初始化会崩溃
lv_port_disp_init(); // 显示器初始化
// lv_port_indev_init(); // 输入设备初始化（如果没有实现就注释掉）
// lv_port_fs_init(); // 文件系统设备初始化（如果没有实现就注释掉）
}
int main(void)
{
LogInit()
BspLedInit();
LCD_ST7735S_Init();
LVGL_Init();
LVGL_CentralButton();
SystemTickInit();
while(1)
{
lv_timer_handler();
LVGL_Delay();
}
}
Stack_Size EQU 0x000040000
AREA STACK, NOINIT, READWRITE, ALIGN=3
Stack_Mem SPACE Stack_Size
__initial_sp
Heap_Size EQU 0x00002000
AREA HEAP, NOINIT,READWRITE,ALIGN=3
__heap_base
Heap_Mem SPACE Heap_Size
__heap_limit
PRESERVE8
THUMB
--diag_suppress=188 --diag_suppress=111 --diag_suppress=550
通过本篇文章的总结，初步对lvgl有了全新的认识。希望对其他开发者有用，谢谢！
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如何学习ruby的正则表达式？(对于假人) 最佳答案 http://www.rubular.com/在Ruby中使用正则表达式时是一个很棒的工具，因为它可以立即将结果可视化。 关于ruby-我如何学习ruby的正则表达式？，我们在StackOverflow上找到一个类似的问题： https://stackoverflow.com/questions/1881231/
深度学习12.CNN经典网络VGG16一、简介1.VGG来源2.VGG分类3.不同模型的参数数量4.3x3卷积核的好处5.关于学习率调度6.批归一化二、VGG16层分析1.层划分2.参数展开过程图解3.参数传递示例4.VGG16各层参数数量三、代码分析1.VGG16模型定义2.训练3.测试一、简介1.VGG来源VGG（VisualGeometryGroup）是一个视觉几何组在2014年提出的深度卷积神经网络架构。VGG在2014年ImageNet图像分类竞赛亚军，定位竞赛冠军；VGG网络采用连续的小卷积核（3x3）和池化层构建深度神经网络，网络深度可以达到16层或19层，其中VGG16和VGG
文章目录1、自相关函数ACF2、偏自相关函数PACF3、ARIMA(p,d,q)的阶数判断4、代码实现1、引入所需依赖2、数据读取与处理3、一阶差分与绘图4、ACF5、PACF1、自相关函数ACF自相关函数反映了同一序列在不同时序的取值之间的相关性。公式：ACF(k)=ρk=Cov(yt,yt−k)Var(yt)ACF(k)=\rho_{k}=\frac{Cov(y_{t},y_{t-k})}{Var(y_{t})}ACF(k)=ρk=Var(yt)Cov(yt,yt−k)其中分子用于求协方差矩阵，分母用于计算样本方差。求出的ACF值为[-1,1]。但对于一个平稳的AR模型，求出其滞
写在之前Shader变体、Shader属性定义技巧、自定义材质面板，这三个知识点任何一个单拿出来都是一套知识体系，不能一概而论，本文章目的在于将学习和实际工作中遇见的问题进行总结，类似于网络笔记之用，方便后续回顾查看，如有以偏概全、不祥不尽之处，还望海涵。1、Shader变体先看一段代码......Properties{ [KeywordEnum(on,off)]USL_USE_COL("IsUseColorMixTex?",int)=0 [Toggle(IS_RED_ON)]_IsRed("IsRed?",int)=0}......//中间省略，后续会有完整代码 #pragmamulti_c
动画/*INITIALIZEANANIMATION 初始化一个动画*-----------------------*/lv_anim_ta;lv_anim_init(&a);/*MANDATORYSETTINGS 必选设置*------------------*//*Setthe"animator"function 设置“动画”功能*/lv_anim_set_exec_cb(&a,(lv_anim_exec_xcb_t)lv_obj_set_x);/*Setthe"animator"function*/lv_anim_set_var(&a,obj);/*Lengthoftheanim
按照目前的情况，这个问题不适合我们的问答形式。我们希望答案得到事实、引用或专业知识的支持，但这个问题可能会引发辩论、争论、投票或扩展讨论。如果您觉得这个问题可以改进并可能重新打开，visitthehelpcenter指导。关闭9年前。我来自C、php和bash背景，很容易学习，因为它们都有相同的C结构，我可以将其与我已经知道的联系起来。然后2年前我学了Python并且学得很好，Python对我来说比Ruby更容易学。然后从去年开始，我一直在尝试学习Ruby，然后是Rails，我承认，直到现在我还是学不会，讽刺的是那些打着简单易学的烙印，但是对于我这样一个老练的程序员来说，我只是无法将它