編輯:關於Android編程
1. 開發環境
Mac OS X , Android Studio 2.1.2
2. 創建新工程
創建SerialPortDemo工程, Minimum SDK 選擇 API 19: Android 4.4。
3. 工程環境
ndk 路徑使用默認的, gradle version 2.10
4. 切換工程顯示方式
5.修改build.gradle
注意是與app目錄同級的build.gradle
修改classpath 對應的版本,請參考:https://sites.google.com/a/android.com/tools/tech-docs/new-build-system/gradle-experimental
gradle version 2.10 目前對應 "com.android.tools.build:gradle-experimental:0.7.0-alpha1"
06.修改app的build.gradle
注意:是app目錄下的build.gradle
新的gradle 參考:https://sites.google.com/a/android.com/tools/tech-docs/new-build-system/gradle-experimental
請注意紅框內的,否則會出現以下一些錯誤:
Error:Cause: org.gradle.api.internal.ExtensibleDynamicObject
Error:No signature of method: org.gradle.model.ModelMap.getDefaultProguardFile() is applicable for argument types: (java.lang.String) values: [proguard-android.txt]
07.創建jni目錄
SerialPort.h
#include#ifndef _Included_com_imlaidian_serialportdemo_serialapi_SerialPort #define _Included_com_imlaidian_serialportdemo_serialapi_SerialPort #ifdef __cplusplus extern "C" { #endif // 命名格式: java_包名_類目錄_類名_接口 JNIEXPORT jobject JNICALL Java_com_imlaidian_serialportdemo_serialapi_SerialPort_open (JNIEnv *, jclass, jstring, jint, jint); JNIEXPORT void JNICALL Java_com_imlaidian_serialportdemo_serialapi_SerialPort_close (JNIEnv *, jobject); #ifdef __cplusplus } #endif #endif
/* * Copyright 2009-2011 Cedric Priscal * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include#include #include #include #include #include #include "termios.h" #include "SerialPort.h" #include "android/log.h" static const char *TAG="serial_port"; #define LOGI(fmt, args...) __android_log_print(ANDROID_LOG_INFO, TAG, fmt, ##args) #define LOGD(fmt, args...) __android_log_print(ANDROID_LOG_DEBUG, TAG, fmt, ##args) #define LOGE(fmt, args...) __android_log_print(ANDROID_LOG_ERROR, TAG, fmt, ##args) static speed_t getBaudrate(jint baudrate) { switch(baudrate) { case 0: return B0; case 50: return B50; case 75: return B75; case 110: return B110; case 134: return B134; case 150: return B150; case 200: return B200; case 300: return B300; case 600: return B600; case 1200: return B1200; case 1800: return B1800; case 2400: return B2400; case 4800: return B4800; case 9600: return B9600; case 19200: return B19200; case 38400: return B38400; case 57600: return B57600; case 115200: return B115200; case 230400: return B230400; case 460800: return B460800; case 500000: return B500000; case 576000: return B576000; case 921600: return B921600; case 1000000: return B1000000; case 1152000: return B1152000; case 1500000: return B1500000; case 2000000: return B2000000; case 2500000: return B2500000; case 3000000: return B3000000; case 3500000: return B3500000; case 4000000: return B4000000; default: return -1; } } /* * Class: android_serialport_SerialPort * Method: open * Signature: (Ljava/lang/String;II)Ljava/io/FileDescriptor; */ JNIEXPORT jobject JNICALL Java_com_imlaidian_serialdemo_SerialPort_SerialPort_open (JNIEnv *env, jclass thiz, jstring path, jint baudrate, jint flags) { int fd; speed_t speed; jobject mFileDescriptor; /* Check arguments */ { speed = getBaudrate(baudrate); if (speed == -1) { /* TODO: throw an exception */ LOGE("Invalid baudrate"); return NULL; } } /* Opening device */ { jboolean iscopy; const char *path_utf = (*env)->GetStringUTFChars(env, path, &iscopy); LOGD("Opening serial port %s with flags 0x%x", path_utf, O_RDWR | flags); fd = open(path_utf, O_RDWR | flags); LOGD("open() fd = %d", fd); (*env)->ReleaseStringUTFChars(env, path, path_utf); if (fd == -1) { /* Throw an exception */ LOGE("Cannot open port"); /* TODO: throw an exception */ return NULL; } } /* Configure device */ { struct termios cfg; LOGD("Configuring serial port"); if (tcgetattr(fd, &cfg)) { LOGE("tcgetattr() failed"); close(fd); /* TODO: throw an exception */ return NULL; } cfmakeraw(&cfg); cfsetispeed(&cfg, speed); cfsetospeed(&cfg, speed); if (tcsetattr(fd, TCSANOW, &cfg)) { LOGE("tcsetattr() failed"); close(fd); /* TODO: throw an exception */ return NULL; } } /* Create a corresponding file descriptor */ { jclass cFileDescriptor = (*env)->FindClass(env, "java/io/FileDescriptor"); jmethodID iFileDescriptor = (*env)->GetMethodID(env, cFileDescriptor, " ", "()V"); jfieldID descriptorID = (*env)->GetFieldID(env, cFileDescriptor, "descriptor", "I"); mFileDescriptor = (*env)->NewObject(env, cFileDescriptor, iFileDescriptor); (*env)->SetIntField(env, mFileDescriptor, descriptorID, (jint)fd); } return mFileDescriptor; } /* * Class: cedric_serial_SerialPort * Method: close * Signature: ()V */ JNIEXPORT void JNICALL Java_com_imlaidian_serialdemo_SerialPort_SerialPort_close (JNIEnv *env, jobject thiz) { jclass SerialPortClass = (*env)->GetObjectClass(env, thiz); jclass FileDescriptorClass = (*env)->FindClass(env, "java/io/FileDescriptor"); jfieldID mFdID = (*env)->GetFieldID(env, SerialPortClass, "mFd", "Ljava/io/FileDescriptor;"); jfieldID descriptorID = (*env)->GetFieldID(env, FileDescriptorClass, "descriptor", "I"); jobject mFd = (*env)->GetObjectField(env, thiz, mFdID); jint descriptor = (*env)->GetIntField(env, mFd, descriptorID); LOGD("close(fd = %d)", descriptor); close(descriptor); }
由於api 19 之後的 termios.h 裡面的函數有調整,因此調試過程中,出現
java.lang.UnsatisfiedLinkError: dlopen failed: cannot locate symbol "tcgetattr" referenced by "libserialport.so"...
解決方法:
將api 19 的 termios.h 拷貝到 jni 目錄下
termios.h
/* * Copyright (C) 2008 The Android Open Source Project * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #ifndef _TERMIOS_H_ #define _TERMIOS_H_ #include#include #include #include #include __BEGIN_DECLS /* Redefine these to match their ioctl number */ #undef TCSANOW #define TCSANOW TCSETS #undef TCSADRAIN #define TCSADRAIN TCSETSW #undef TCSAFLUSH #define TCSAFLUSH TCSETSF static __inline__ int tcgetattr(int fd, struct termios *s) { return ioctl(fd, TCGETS, s); } static __inline__ int tcsetattr(int fd, int __opt, const struct termios *s) { return ioctl(fd, __opt, (void *)s); } static __inline__ int tcflow(int fd, int action) { return ioctl(fd, TCXONC, (void *)(intptr_t)action); } static __inline__ int tcflush(int fd, int __queue) { return ioctl(fd, TCFLSH, (void *)(intptr_t)__queue); } static __inline__ pid_t tcgetsid(int fd) { pid_t _pid; return ioctl(fd, TIOCGSID, &_pid) ? (pid_t)-1 : _pid; } static __inline__ int tcsendbreak(int fd, int __duration) { return ioctl(fd, TCSBRKP, (void *)(uintptr_t)__duration); } static __inline__ speed_t cfgetospeed(const struct termios *s) { return (speed_t)(s->c_cflag & CBAUD); } static __inline__ int cfsetospeed(struct termios *s, speed_t speed) { s->c_cflag = (s->c_cflag & ~CBAUD) | (speed & CBAUD); return 0; } static __inline__ speed_t cfgetispeed(const struct termios *s) { return (speed_t)(s->c_cflag & CBAUD); } static __inline__ int cfsetispeed(struct termios *s, speed_t speed) { s->c_cflag = (s->c_cflag & ~CBAUD) | (speed & CBAUD); return 0; } static __inline__ void cfmakeraw(struct termios *s) { s->c_iflag &= ~(IGNBRK|BRKINT|PARMRK|ISTRIP|INLCR|IGNCR|ICRNL|IXON); s->c_oflag &= ~OPOST; s->c_lflag &= ~(ECHO|ECHONL|ICANON|ISIG|IEXTEN); s->c_cflag &= ~(CSIZE|PARENB); s->c_cflag |= CS8; } __END_DECLS #endif /* _TERMIOS_H_ */
http://jp1017.github.io/2016/06/30/jni-開發錯誤之-java-lang-UnsatisfiedLinkError-dlopen-failed-cannot-locate-symbol-tcgetattr-referenced-by-libserial-port-so/
http://www.eoeandroid.com/thread-914514-1-1.html
08.創建串口native接口類
SerialPort.java
/* * Copyright 2009 Cedric Priscal * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.imlaidian.serialportdemo.serialapi; import java.io.File; import java.io.FileDescriptor; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import android.util.Log; public class SerialPort { private static final String TAG = "SerialPort"; /* * Do not remove or rename the field mFd: it is used by native method close(); */ private FileDescriptor mFd; private FileInputStream mFileInputStream; private FileOutputStream mFileOutputStream; public SerialPort(File device, int baudrate, int flags) throws SecurityException, IOException { /* Check access permission */ if (!device.canRead() || !device.canWrite()) { try { /* Missing read/write permission, trying to chmod the file */ Process su; su = Runtime.getRuntime().exec("/system/bin/su"); String cmd = "chmod 666 " + device.getAbsolutePath() + "\n" + "exit\n"; su.getOutputStream().write(cmd.getBytes()); if ((su.waitFor() != 0) || !device.canRead() || !device.canWrite()) { throw new SecurityException(); } } catch (Exception e) { e.printStackTrace(); throw new SecurityException(); } } mFd = open(device.getAbsolutePath(), baudrate, 8, 1,'n'); if (mFd == null) { Log.e(TAG, "native open returns null"); throw new IOException(); } mFileInputStream = new FileInputStream(mFd); mFileOutputStream = new FileOutputStream(mFd); } // Getters and setters public InputStream getInputStream() { return mFileInputStream; } public OutputStream getOutputStream() { return mFileOutputStream; } // JNI private native static FileDescriptor open(String path, int baudrate, int databits,int stopbits,char parity); public native void close(); static { System.loadLibrary("serialport"); // 調用jni生成的庫 } }
SerialPortFinder.java
/* * Copyright 2009 Cedric Priscal * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.imlaidian.serialportdemo.serialapi; import java.io.File; import java.io.FileReader; import java.io.IOException; import java.io.LineNumberReader; import java.util.Iterator; import java.util.Vector; import android.util.Log; public class SerialPortFinder { public class Driver { public Driver(String name, String root) { mDriverName = name; mDeviceRoot = root; } private String mDriverName; private String mDeviceRoot; VectormDevices = null; public Vector getDevices() { if (mDevices == null) { mDevices = new Vector (); File dev = new File("/dev"); File[] files = dev.listFiles(); int i; for (i=0; i mDrivers = null; Vector getDrivers() throws IOException { if (mDrivers == null) { mDrivers = new Vector (); LineNumberReader r = new LineNumberReader(new FileReader("/proc/tty/drivers")); String l; while((l = r.readLine()) != null) { // Issue 3: // Since driver name may contain spaces, we do not extract driver name with split() String drivername = l.substring(0, 0x15).trim(); String[] w = l.split(" +"); if ((w.length >= 5) && (w[w.length-1].equals("serial"))) { Log.d(TAG, "Found new driver " + drivername + " on " + w[w.length-4]); mDrivers.add(new Driver(drivername, w[w.length-4])); } } r.close(); } return mDrivers; } public String[] getAllDevices() { Vector devices = new Vector (); // Parse each driver Iterator itdriv; try { itdriv = getDrivers().iterator(); while(itdriv.hasNext()) { Driver driver = itdriv.next(); Iterator itdev = driver.getDevices().iterator(); while(itdev.hasNext()) { String device = itdev.next().getName(); String value = String.format("%s (%s)", device, driver.getName()); devices.add(value); } } } catch (IOException e) { e.printStackTrace(); } return devices.toArray(new String[devices.size()]); } public String[] getAllDevicesPath() { Vector devices = new Vector (); // Parse each driver Iterator itdriv; try { itdriv = getDrivers().iterator(); while(itdriv.hasNext()) { Driver driver = itdriv.next(); Iterator itdev = driver.getDevices().iterator(); while(itdev.hasNext()) { String device = itdev.next().getAbsolutePath(); devices.add(device); } } } catch (IOException e) { e.printStackTrace(); } return devices.toArray(new String[devices.size()]); } }
09.gradle sync同步
10. 生成.so 路徑
Fence是一種同步機制,在Android裡主要用於圖形系統中GraphicBuffer的同步。那它和已有同步機制相比有什麼特點呢?它主要被用來處理跨硬件的情況,尤其是C
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項目效果如下:項目目錄結構如下:代碼如下:AudioManager.javapackage com.xuliugen.weichat;import java.io.Fil
Dev Club 是一個交流移動開發技術,結交朋友,擴展人脈的社群,成員都是經過審核的移動開發工程師。每周都會舉行嘉賓分享,話題討論等活動。本期,我們邀請了騰訊WXG A