android RK3328 gpio处理

• 使用shell命令测试你的gpio并找到对应端口

详细请看：

• shell命令工具类

package cn.hxg.androidgpiotest;

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;

import android.util.Log;

/**
 * 执行shell脚本工具类
 *
 * @author Mountain
 */
public class CommandExecution {

    public static final String TAG = "CommandExecution";

    public final static String COMMAND_SU = "su";
    public final static String COMMAND_SH = "sh";
    public final static String COMMAND_EXIT = "exit\n";
    public final static String COMMAND_LINE_END = "\n";

    /**
     * Command执行结果
     *
     * @author Mountain
     */
    public static class CommandResult {
        public int result = -1;
        public String errorMsg;
        public String successMsg;
    }

    /**
     * 执行命令—单条
     *
     * @param command
     * @param isRoot
     * @return
     */
    public static CommandResult execCommand(String command, boolean isRoot) {
        String[] commands = {command};
        return execCommand(commands, isRoot);
    }

    /**
     * 执行命令-多条
     *
     * @param commands
     * @param isRoot
     * @return
     */
    public static CommandResult execCommand(String[] commands, boolean isRoot) {
        CommandResult commandResult = new CommandResult();
        if (commands == null || commands.length == 0) return commandResult;
        Process process = null;
        DataOutputStream os = null;
        BufferedReader successResult = null;
        BufferedReader errorResult = null;
        StringBuilder successMsg = null;
        StringBuilder errorMsg = null;
        try {
            process = Runtime.getRuntime().exec(isRoot ? COMMAND_SU : COMMAND_SH);
            os = new DataOutputStream(process.getOutputStream());
            for (String command : commands) {
                if (command != null) {
                    os.write(command.getBytes());
                    os.writeBytes(COMMAND_LINE_END);
                    os.flush();
                }
            }
            os.writeBytes(COMMAND_EXIT);
            os.flush();
            commandResult.result = process.waitFor();

            //获取错误信息
            successMsg = new StringBuilder();
            errorMsg = new StringBuilder();
            successResult = new BufferedReader(new InputStreamReader(process.getInputStream()));
            errorResult = new BufferedReader(new InputStreamReader(process.getErrorStream()));
            String s;
            while ((s = successResult.readLine()) != null) successMsg.append(s);
            while ((s = errorResult.readLine()) != null) errorMsg.append(s);
            commandResult.successMsg = successMsg.toString();
            commandResult.errorMsg = errorMsg.toString();
            Log.i(TAG, commandResult.result + " | " + commandResult.successMsg
                    + " | " + commandResult.errorMsg);
        } catch (IOException e) {
            String errmsg = e.getMessage();
            if (errmsg != null) {
                Log.e(TAG, errmsg);
            } else {
                e.printStackTrace();
            }
        } catch (Exception e) {
            String errmsg = e.getMessage();
            if (errmsg != null) {
                Log.e(TAG, errmsg);
            } else {
                e.printStackTrace();
            }
        } finally {
            try {
                if (os != null) os.close();
                if (successResult != null) successResult.close();
                if (errorResult != null) errorResult.close();
            } catch (IOException e) {
                String errmsg = e.getMessage();
                if (errmsg != null) {
                    Log.e(TAG, errmsg);
                } else {
                    e.printStackTrace();
                }
            }
            if (process != null) process.destroy();
        }
        return commandResult;
    }

}

• gpio读写操作

package cn.hxg.androidgpiotest;

import android.os.Bundle;
import android.os.SystemClock;
import android.util.Log;

import androidx.appcompat.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity {

    private String[] gpioShell = {"cd /sys/class/gpio", "echo 3 > export",
            "cd gpio3", "echo in >direction", "chmod 777 value"};

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        new Thread(new Runnable() {
            @Override
            public void run() {
                if (FileUtils.fileIsExists("/sys/class/gpio/gpio3")) {
                    CommandExecution.CommandResult commandResult = CommandExecution.execCommand(gpioShell, true);
                    Log.e("huang", commandResult.result + " | " + commandResult.successMsg
                            + " | " + commandResult.errorMsg);
                    while (true) {
                        SystemClock.sleep(1000);
                        String s = FileUtils.ReadTxtFile("/sys/class/gpio/gpio3/value");
                        Log.i("huang", "s===>" + s);
                    }
                }
            }
        }).start();
    }
}

• 文件操作类

package cn.hxg.androidgpiotest;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

public class FileUtils {
    //判断文件是否存在
    public static boolean fileIsExists(String filePath) {
        try {
            File f = new File(filePath);
            if (!f.exists()) {
                return false;
            }
        } catch (Exception e) {
            return false;
        }
        return true;
    }

    /**
     * 读取文件
     *
     * @param strFilePath
     * @return
     */
    public static String ReadTxtFile(String strFilePath) {
        String path = strFilePath;
        String content = ""; //文件内容字符串
        //打开文件
        File file = new File(path);
        if (!file.exists()) {  //文件不存在
            return content;
        }
        //如果path是传递过来的参数，可以做一个非目录的判断
        if (!file.isDirectory()) {
            try {
                InputStream instream = new FileInputStream(file);
                if (instream != null) {
                    InputStreamReader inputreader = new InputStreamReader(instream);
                    BufferedReader buffreader = new BufferedReader(inputreader);
                    String line;
                    //分行读取
                    while ((line = buffreader.readLine()) != null) {
                        content += line + "\n";
                    }
                    instream.close();
                }
            } catch (java.io.FileNotFoundException e) {
            } catch (IOException e) {
            }
        }
        return content;
    }
}

• 结果显示