（1）打印机：首先要选择一个连接内网的打印机，内网打印机就是和手机用的同一个网络。
（2）手机：手机必须连接wifi才行。
一个按钮，点击此按钮进行打印操作：
button.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
PrintUtil printUtil = new PrintUtil(context,path); //context：上下文对象 path:需要打印的图片的路径
}
});
PrintUtil:
public class PrintUtil {
public static String IPADDRESS;
public Socket socket;
public static final int POS_OPEN_NETPORT = 9100;
public static String IPADRESS;
public int Net_ReceiveTimeout = 2500;
Context context;
String path;
public PrintUtil(Context context,String path) {
super();
this.context = context;
this.path = path;
IPADDRESS = getIPAddress(context);
RunThread run = new RunThread();
run.start();
}
/*
* 获取当前手机所连wifi的ip地址
*/
public static String getIPAddress(Context context) {
NetworkInfo info = ((ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE))
.getActiveNetworkInfo();
if (info != null && info.isConnected()) {
if (info.getType() == ConnectivityManager.TYPE_MOBILE) {// 当前使用2G/3G/4G网络
try {
for (Enumeration<NetworkInterface> en = NetworkInterface
.getNetworkInterfaces(); en.hasMoreElements();) {
NetworkInterface intf = en.nextElement();
for (Enumeration<InetAddress> enumIpAddr = intf
.getInetAddresses(); enumIpAddr
.hasMoreElements();) {
InetAddress inetAddress = enumIpAddr.nextElement();
if (!inetAddress.isLoopbackAddress()
&& inetAddress instanceof Inet4Address) {
return inetAddress.getHostAddress();
}
}
}
} catch (SocketException e) {
e.printStackTrace();
}
} else if (info.getType() == ConnectivityManager.TYPE_WIFI) {// 当前使用无线网络
WifiManager wifiManager = (WifiManager) context
.getSystemService(Context.WIFI_SERVICE);
WifiInfo wifiInfo = wifiManager.getConnectionInfo();
String ipAddress = intIP2StringIP(wifiInfo.getIpAddress());// 得到IPV4地址
return ipAddress;
}
} else {
// 当前无网络连接,请在设置中打开网络
}
return null;
}
/**
* 将得到的int类型的IP转换为String类型,截取ip的前三段
*
* @param ip
* @return
*/
public static String intIP2StringIP(int ip) {
return (ip & 0xFF) + "." + ((ip >> 8) & 0xFF) + "."
+ ((ip >> 16) & 0xFF) + ".";
}
ScheduledExecutorService pool;
boolean isFinish;
long lastFinishTime = 0;
boolean isHave = false;
private class RunThread extends Thread{
public RunThread(){
}
@Override
public void run() {
if(pool==null){
pool = Executors.newScheduledThreadPool(100);
}
for (int i = 2; i < 255; ++i) { //0~255循环找到打印机ip
final int index = i;
pool.execute(new Runnable() {
@Override
public void run() {
try {
String ipaddress = IPADDRESS + index;
NetPrinter printer = new NetPrinter();
printer.Open(ipaddress, NetPrinter.POS_OPEN_NETPORT);
if (printer.IFOpen) { //找到打印机
isHave = true;
pos(ipaddress);
handler.sendEmptyMessage(0);
return;
} else{
if(index == 254 && isHave == false){
handler.sendEmptyMessage(1);
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
});
}
}
}
private Handler handler = new Handler(){
public void handleMessage(Message msg) {
switch (msg.what) {
case 0:
Toast.makeText(context, "打印完成！", Toast.LENGTH_SHORT).show();
break;
case 1:
Toast.makeText(context, "未找到打印机，请确认打印机在同一局域网内，谢谢！", Toast.LENGTH_SHORT).show();
break;
default:
break;
}
};
};
private void pos(final String ip) {
// 开启一个子线程
new Thread() {
public void run() {
try { // 打印机网口IP 打印机端口号 编码方式
printImage(ip);
} catch (UnknownHostException e) {
e.printStackTrace();
Log.d("tag", "错误信息1：" + e.toString());
} catch (IOException e) {
e.printStackTrace();
Log.d("tag", "错误信息2：" + e.toString());
}
}
}.start();
}
//根据IP地址使用打印机打印图片
public void printImage(String ip) throws IOException {
DataOutputStream outToServer = null;
Socket clientSocket;
FileInputStream fileInputStream;
try {
fileInputStream = new FileInputStream(path);
InputStream is = fileInputStream;
clientSocket = new Socket(ip, 9100);
outToServer = new DataOutputStream(clientSocket.getOutputStream());
byte[] buffer = new byte[3000];
while (is.read(buffer) != -1) {
outToServer.write(buffer);
}
outToServer.flush();
} catch (ConnectException connectException) {
Log.e("msg", connectException.toString(), connectException);
} catch (UnknownHostException e1) {
Log.e("msg", e1.toString(), e1);
} catch (IOException e1) {
Log.e("msg", e1.toString(), e1);
} finally {
outToServer.close();
}
}
public void deleteAll(File file) {
if (file.isFile() || file.list().length == 0) {
file.delete();
} else {
for (File f : file.listFiles()) {
deleteAll(f); // 递归删除每一个文件
}
file.delete(); // 删除文件夹
}
}
}
NetPrinter:
public class NetPrinter {
public Socket socket;
private static final String DEBUG_TAG="NetPrinter";
public static final int POS_OPEN_NETPORT = 9100;
public boolean IFOpen = false;
public int Net_ReceiveTimeout = 2500;
//网络打印机 打开网络打印机
public boolean Open(String ipaddress, int netport) {
if (socket == null) {
try {
SocketAddress ipe = new InetSocketAddress(Inet4Address.getByName(ipaddress) ,netport);
Log.e(DEBUG_TAG, Inet4Address.getByName(ipaddress)+"|"+netport);
socket = new Socket();
socket.connect(ipe, Net_ReceiveTimeout); //2500ms连接时间，连接不上返回false
IFOpen = true;
} catch(Exception e) {
IFOpen = false;
}
} else {
try {
socket.close();
SocketAddress ipe = new InetSocketAddress(Inet4Address.getByName(ipaddress),netport);
Log.e(DEBUG_TAG, Inet4Address.getByName(ipaddress)+"|"+netport);
socket = new Socket();
socket.connect(ipe,Net_ReceiveTimeout);
IFOpen = true;
} catch(Exception e) {
IFOpen = false;
}
}
if(IFOpen){
Close();
}
return IFOpen;
}
//网络打印机 关闭
public void Close() {
try {
socket.close();
socket = null;
} catch(Exception e) {
e.printStackTrace();
}
}
}
以上代码就能轻松实现图片的打印，这里我考虑的仅仅只是一台打印机的情况，我这里也只有一台，哈哈。
有什么不足之处请大家指教一下。
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