Huawei cloud 14 day Hongmeng device development -day1 source code acquisition

---

Preface

In the previous article, the environment was built , The next step is to do the code , First of all, we have to have the source code , And then in Windows Can open edit , Next, let's try .
First, give a few open source websites
Source source repository ：https://gitee.com/openharmony
Device development learning website ：https://device.harmonyos.com/cn/home
HPM Website ：https://developer.harmonyos.com/cn/home/

---

One 、 Access to the source code

1. Source code acquisition method

1.1 Get... From the mirror site

Download compressed files from the image site , Then, as in the previous article , Create one code Catalog , Drag and drop the compressed file to unzip .
https://repo.huaweicloud.com/harmonyos/os/1.0/code-1.0.tar.gz
a. Create a code directory under the root directory

 mkdir code # Create a file called code Folder 
 cd code/
 ls
 mkdir code_1
 cd code_1/
 ls# View the contents of the current directory 

b. Directly from Windows Drag and drop in
c. Unzip to the current directory

   tar -xvf code-1.0.tar.gz  

It can also be in Linux The terminal enters the specified directory , Use wget Instruction get compressed package , Then perform the decompression operation .

1.2 from HPM Website component access

HPM Website ：https://hpm.harmonyos.com/#/cn/home
Soft environment requirements ：Linux Environmental installation 12.13.0+ Of Node.js
Therefore, the following installation should be carried out in this way
a. install Node.js

# download Nodejs
wget https://nodejs.org/dist/v14.15.1/node-v14.15.1-linux-x64.tar.xz
# decompression 
tar -xvf node-v14.15.1-linux-x64.tar.xz-C  ~/
# Use  ln  Command to set up the soft connection 
sudo ln -s ~/node-v14.15.1-linux-x64/bin/npm /usr/bin/ 
sudo ln -s ~/node-v14.15.1-linux-x64/bin/node   /usr/bin/

b. install hpm Command line tools

npm install -g @ohos/hpm-cli
sudo ln -s ~/node-v14.15.1-linux-x64/bin/hpm /usr/bin/

c. adopt hpm install Command to install components
stay Windows From the system HPM Choose the components you need on the website , And click to download directly , Then drag and drop Linux Under the specified directory of the virtual machine , Decompress and execute hpm Installation instructions for (hpm install）, Will automatically download components and install . Drag and drop to unzip. Refer to the commands in the previous method .

 cd code/
 ls
 mkdir code_2
 cd code_2/
 unzip demo.zip
 cd demo/
 hpm install

1.3 Use the package manager command line to get

Applicable scenario

• Users have obtained the source code through component acquisition , One or several components in the source code need to be upgraded independently .
• Users are already familiar with HarmonyOS Develop the system and master the use of command line tools .
  This method also needs to install the tools in the second method .
  For example, the obtained component name is @bearpi/bearpi_hm_nano, The specific operation is as follows ：

1、 Enter the Development Directory , Execute the following command , Create a development project using the default template

      cd code/
      ls
      mkdir code_3
      cd code_3/
     hpm init -t default

2、 Execute the following command , Installation of components @bearpi/bearpi_hm_nano
hpm install @bearpi/bearpi_hm_nano
3、 The tool will automatically download all dependent components from the server , If the download is successful, it will display Installed.
from HPM When downloading components from the website, you can customize and add other component packages , The default dependent component package cannot be deleted .

1.4 Get from the code repository

download Harmony OS Source code
Before that, you need to register gitee account number , And configure the mailbox .
Source link ：https://gitee.com/bearpi/bearpi-hm_nano
First in Linux Create a directory to store code .
stay Linux Execute the following commands under the terminal

git config --global user.name "yourname"
git config --global user.email “your-email-address"
git clone https://gitee.com/bearpi/bearpi-hm_nano.git -b master

Compile command

python build.py BearPi-HM_Nano

This is the easy way , I use this method . Note that you need to install git.

sudo apt install git

Two 、 stay Windows Open the project source code

Introduction to source directory

1. Mapping project source code

at present HarmonyOS The source code only supports Linux Compile in the system , Can be Linux The project directory in the environment is mapped to Windows In the environment , And then use VS Code open , And in Windows Burning and debugging in the environment . This shared folder method requires samba. The mapping method is as follows ：
1、 stay Linux On , Set up HarmonyOS The folder where the source code is located is a shared folder .

# install Samba
sudo apt-get install samba
# To configure Samba
sudo vim /etc/samba/smb.conf
# Add the following 
[HarmonyOS_Code]
path = /home/YOUR_USER_NAME/code
available = yes
valid users = YOUR_USER_NAME
read only = no
browsable = yes
public = yes
writable = yes
# Set up Samba User name and password 
sudo smbpasswd -a YOUR_USER_NAME
# restart samba service  
sudo /etc/init.d/smbd restart

2. Import project source code

1. stay Windows On , Right click “ This computer ”, choice “ Mapping network drives （N）.
2. Select an unused drive , And set up HarmonyOS Path of source code , The format is “\Linux IP Address \ Shared folder name ”, Such as ：\192.168.0.224\HarmonyOS_Code, Click on “ complete ”.

3. Open the source code of the project

Double click to enter the shared folder , Directly drag and drop the corresponding directory to VS CODE You can open it in .

3、 ... and 、Hello World

1. To write Hello World Program

1. newly added my_app Folder
   stay ./applications/BearPi/BearPi-HM_Nano/sample Create a new one under the path my_app Catalog , Used to store business source code files .
2. newly added hello_world.c file
   stay ./applications/BearPi/BearPi-HM_Nano/sample/my_app Create a new one under the path hello_world.c file , This file is the business source code file .
3. newly added BUILD.gn file
   stay ./applications/BearPi/BearPi-HM_Nano/sample/my_app Create a new one under the path BUILD.gn file , This file compiles the script for the business source code .
   This step is a little similar to Cmake.
   And then start writing code .
   Business code
   stay hello_world.c Create a new business entry function in Hello_World, And implement business logic . And at the bottom of the code , Use HarmonyOS Start the recovery module interface APP_FEATURE_INIT() Start the business .（APP_FEATURE_INIT It's defined in ohos_init.h In file ）

#include <stdio.h>
#include "ohos_init.h"
void Hello_World(void)
{
    
  printf("Hello World!\r\n");
}
APP_FEATURE_INIT(Hello_World);

gn File code

instructions ： Hi3861 The platform only supports libgcc Static links to runtime libraries , Developers are not recommended to use libgcc Dynamic link of runtime library , It will cause commercial distribution to be GPL V3 Pollution .

1. Write a code for building a business into a static library BUILD.gn file
   stay ./applications/BearPi/BearPi-HM/sample/my_app Under the BUILD.gn Add the following code to the file .

static_library("myapp") {
    
    sources = [
        "hello_world.c"
    ]

    include_dirs = [
        "//utils/native/lite/include",
    ]
}

• static_library The compilation result of the specified business module in , For static library files libmyapp.a, The developer shall fill in according to the actual situation .
• sources Specify a static library in .a The dependent .c File and its path , If the path contains "//“ Absolute path （ Here is the code root path ）, If it doesn't include ”//" Indicates the relative path .
• include_dirs It is specified in source What we need to rely on .h File path .

2. Writing module BUILD.gn file , Specify the feature modules to be built .
   stay ./applications/BearPi/BearPi-HM/sample Under the BUILD.gn Add the following code to the file .
   

• my_app Is a relative path , Point to ./applications/BearPi/BearPi-HM/sample/my_app/BUILD.gn.
• myapp Is the target , Point to ./applications/BearPi/BearPi-HM/sample/my_app/BUILD.gn Medium static_library(“myapp”).

2. Compiling and burning programs

1. Device manager check the board COM mouth
   

2. open HiBurn Change port , The baud rate is set to 921600

3. Select burn file
   

4. Check Auto burn, Click on connect, Press the development board reset Key , Start the download .
   

5. When the download is complete , Click on disconnect.

3. debugging

1. stay Visual Studio Code Bottom , Click on “ A serial port ” Button icon .
2. Enter the port number , Other parameters remain the default configuration .
3. Press the development board RESET Key , Log information can be output .