Libusb库在Android下的使用例程

偏执的太偏执、 2022-07-11 16:26 375阅读 0赞

转载请注明：[http://blog.csdn.net/hubbybob1/article/details/54863662][http_blog.csdn.net_hubbybob1_article_details_54863662]  
阅读本文前清先了解相关基础内容，操作步骤请阅读博客：[libusb1.0在android内的移植和使用方法][libusb1.0_android]  
在讲解了libusb库在Android下的移植和基本应用后，下面来讲解Libusb的Android工程；

其工程步骤：  
1.建立带有JNI工程的eclipse工程，网上有很多教程  
2.根据上一篇博客生成libusb.a库文件和相关头文件（libusb.h等）,并导入JNI工程.  
3.编写Android.mk，可以通过ndk-build进行编译C文件到工程里面去如下所示：

LOCAL_PATH := $(call my-dir)
    include $(CLEAR_VARS)
    
    
    LOCAL_CFLAGS := -D__STDC_CONSTANT_MACROS
    CROSS_DIR  := /opt/gstreamer
    spice_objs := \
                $(LOCAL_PATH)/libs/lib/libusb.a
    
    LOCAL_SRC_FILES := android-jni-interface.c
    
    LOCAL_LDLIBS += $(spice_objs) -llog
    
    LOCAL_C_INCLUDES += \
            $(LOCAL_PATH)/libs/include/libusb \
            $(CROSS_DIR)/include/glib-2.0 \
            $(CROSS_DIR)/lib/glib-2.0/include
    
    #LOCAL_SHARED_LIBRARIES := libmyaudio
    
    LOCAL_MODULE := libxxtest
    
    include $(BUILD_SHARED_LIBRARY)

4.编写C文件并进行ndk-build编译，如下所示：

#include <jni.h>
    #include <android/log.h>
    #include <stddef.h>
    #include "libusb.h"
    #include <glib.h>
    #define LOG_TAG "MediaRecorder"
    #define LOG(...) __android_log_print(ANDROID_LOG_DEBUG,LOG_TAG, __VA_ARGS__)
    //#define FALSE 0
    JNIEXPORT void JNICALL
    Java_com_example_testcusejava_Testcusenative_libusbcallfunc(JNIEnv* env, jobject obj)
    {
        //openUsbDevice(4703,12587);
        int rc,r;
        libusb_device_handle *handle = NULL;
        libusb_device *device;
        libusb_context *ctx = NULL;
         r = libusb_init(&ctx);//启动libusb
    
         jclass class  = (*env)->FindClass (env, "com/example/testcusejava/Testcusenative");
        jmethodID openUsbDevice = (*env)->GetStaticMethodID(env, class, "openUsbDevice", "(II)I");//GetStaticMethodID GetMethodID，通过jni获取Java的方法openUsbDevice
        int fd =(*env)->CallStaticIntMethod(env, class,openUsbDevice ,4703,12587);//CallVoidMethod,CallStaticIntMethod调用openUsbDevice 获取fd
        LOG("!!!!!一二三!!!!! fd = %d",fd);
        __android_log_write(6, "android-service", "Trying to open USB device.get_usb_device_fd");
        //rc = libusb_open_fd(device, &handle,fd);//打开usb设备
        if (rc != 0) { __android_log_write(6, "channel-usbredir", "Failed to open USB device."); }
    
        //libusb_close(handle);
        libusb_exit(ctx); //结束libusb
    }

5.编写Java程序

package com.example.testcusejava;
    
    import java.io.IOException;
    import java.nio.ByteBuffer;
    import java.util.Collection;
    import java.util.HashMap;
    import java.util.Iterator;
    
    import com.example.testcusejava.R;
    import com.example.testcusejava.Testcusenative.MyThread2;
    import com.example.testcusejava.Testcusenative.MyThread3;
    
    import android.app.Activity;
    import android.app.PendingIntent;
    import android.content.BroadcastReceiver;
    import android.content.Context;
    import android.content.Intent;
    import android.content.IntentFilter;
    import android.hardware.usb.UsbDevice;
    import android.hardware.usb.UsbDeviceConnection;
    import android.hardware.usb.UsbEndpoint;
    import android.hardware.usb.UsbInterface;
    import android.hardware.usb.UsbManager;
    import android.hardware.usb.UsbRequest;
    import android.os.Bundle;
    import android.os.Handler;
    import android.os.Message;
    import android.util.Log;
    import android.view.Menu;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.widget.Toast;
    
    //bhw 2016.07.19 e
    
    public class Testcusenative extends Activity {   
        public native void libusbfunc();// 调用native方法 
    static {
            System.loadLibrary("xxtest");//加载ndk-build生成的libxxtest.so库
        }
    
        private Button button,button2;
        private UsbManager usbManager;
        private UsbDevice usbDevice;
        private static final String ACTION_USB_PERMISSION = "com.android.example.USB_PERMISSION";
        private PendingIntent pendingIntent;
        static int fd = -1;
    
        private Handler handler = new Handler(){
            @Override
            public void handleMessage(Message msg) {
                // TODO Auto-generated method stub
                super.handleMessage(msg);
                switch (msg.what) {
                case 3:
                    Toast.makeText(Testcusenative.this, "33333333333333333", 0).show();
                    break;
                case 4:
                    Toast.makeText(Testcusenative.this, "44444444444444444", 0).show();
                    break;
    
                }
            }
        };
    
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_testcusenative);           
            try {
                Process process = Runtime.getRuntime().exec("su");
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }   
            button = (Button) findViewById(R.id.buttonPlay);
            usbManager = (UsbManager) getSystemService(Context.USB_SERVICE);    
            pendingIntent = PendingIntent.getBroadcast(this, 0, new Intent(ACTION_USB_PERMISSION), 0);
            IntentFilter filter = new IntentFilter(ACTION_USB_PERMISSION);
            registerReceiver(mUsbReceiver, filter);
    
            button.setOnClickListener(new OnClickListener() {
                @Override
                public void onClick(View arg0) {
                    // TODO Auto-generated method stub
                    Log.e("device","call MyThread2 ");
                    new MyThread2().start();
    
                // libusbfunc();// 调用native方法 }
            });
    
    
        }
        @Override
        public boolean onCreateOptionsMenu(Menu menu) {
            // Inflate the menu; this adds items to the action bar if it is present.
            getMenuInflater().inflate(R.menu.testcusenative, menu);
            return true;
        }
    
    
        public static native void test();
        static{
             //System.loadLibrary("lianyinbao-jni");
        }
    
        class MyThread2 extends Thread{
    
            @Override
            public void run() {
                // TODO Auto-generated method stub
                super.run();
                try {
                    UsbDevice ud= null;
                    //链接到设备的USB设备列表
                    HashMap<String, UsbDevice> map = usbManager.getDeviceList();
    
                    Collection<UsbDevice> usbDevices = map.values();
                    Iterator<UsbDevice> usbDeviceIter = usbDevices.iterator();
                    while (usbDeviceIter.hasNext()){
                        ud = usbDeviceIter.next();  
                        //VendorID 和ProductID 十进制 
                        if(4703 == ud.getVendorId() && 12587 == ud.getProductId()){
       //vid pid 3141 25409 ; 4703 12587
                       usbDevice = ud;
                       Log.e("device","find device"); //bhw 
                        }
                        //Log.e("device","find device"); //bhw
                    }
    
                    //检测USB设备权限受否授权
                    if(usbManager.hasPermission(usbDevice)){
                        handler.sendEmptyMessage(3);
                        new MyThread3().start();
                        Log.e("device","usbManager.hasPermission");//bhw
                    }else{
                        //如果没有授权就授予权限
                        handler.sendEmptyMessage(4);
                        usbManager.requestPermission(usbDevice, pendingIntent); //在此Android系统会弹出对话框，选择是否授予权限 
                        Log.e("device","usbManager.requestPermission");   //bhw 
                    }               
                } catch (Exception e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        }
    
        class MyThread3 extends Thread{
            @Override
            public void run() {
                // TODO Auto-generated method stub
                super.run();
                Log.e("device","MyThread3");//bhw
                UsbDeviceConnection connection = usbManager.openDevice(usbDevice);          
                fd = connection.getFileDescriptor();//获取文件描述符
                Log.e("device","MyThread3 "+fd);       
                jnicallfunc();//调用native方法 }
        }
        public static int openUsbDevice(int vid, int pid) throws InterruptedException {
    
            Log.e("device","openUsbDevice "+fd);
            return fd;
    
        }
        private final BroadcastReceiver mUsbReceiver = new BroadcastReceiver() {
    
            public void onReceive(Context context, Intent intent) {
                String action = intent.getAction();
                Log.e( "action", action);
    
                if (ACTION_USB_PERMISSION.equals(action)) {
                    synchronized (this) {
                        usbDevice = (UsbDevice)intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);
                        if (intent.getBooleanExtra(UsbManager.EXTRA_PERMISSION_GRANTED, false)) {
                            handler.sendEmptyMessage(1)                  
                            if(usbDevice != null){
                              new MyThread3().start();//MyThread3
                           }
                        } 
                        else {
                            Log.d("denied", "permission denied for device " + usbDevice);
                        }
                    }
                }
            }
           };   
    }

当编写完后的运行结果如下图：  
![这里写图片描述][SouthEast]  
打印的信息顺序为下图：  
![这里写图片描述][SouthEast 1]  
到此主要的程序已经完毕，本程序[eclipse的工程代码下载][eclipse]

[http_blog.csdn.net_hubbybob1_article_details_54863662]: http://blog.csdn.net/hubbybob1/article/details/54863662
[libusb1.0_android]: http://blog.csdn.net/hubbybob1/article/details/52244999
[SouthEast]: /images/20220711/44e33672efc340c3b1ec8014c30d8320.png
[SouthEast 1]: /images/20220711/3f8fc72955a54388b8157d76d523fb7b.png
[eclipse]: http://download.csdn.net/detail/hubbybob1/9921459