Question

有人能告诉我如何通过蓝牙连接移动和打印机来在Android中打印文本文件？

也就是说，如果我点击Android应用程序中的打印按钮，打印机必须打印相应的文件。据我所知，我已经在谷歌搜索过它，但我找不到任何好的样本来做。有人至少有一个样本安卓程序可以做到这一点，最好清除我的混乱。

建议请。谢谢你宝贵的时间！..

Answer 1

蓝牙打印机Android示例在编辑器中创建一个新的Android项目BlueToothPrinterApp。

第1步：

创建如下的主要活动

com.example.BlueToothPrinterApp/BlueToothPrinterApp.java

package com.example.BlueToothPrinterApp;

import android.app.Activity;
import android.os.Bundle;
import java.io.IOException;
import java.io.OutputStream;
import android.bluetooth.BluetoothSocket;
import android.content.ContentValues;
import android.content.Intent;
import android.os.Environment;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class BlueToothPrinterApp extends Activity
{
/** Called when the activity is first created. */
EditText message;
Button printbtn;

byte FONT_TYPE;
private static BluetoothSocket btsocket;
private static OutputStream btoutputstream;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
message = (EditText)findViewById(R.id.message);
printbtn = (Button)findViewById(R.id.printButton);

printbtn.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View v) {
connect();
}
});
}

protected void connect() {
if(btsocket == null){
Intent BTIntent = new Intent(getApplicationContext(), BTDeviceList.class);
this.startActivityForResult(BTIntent, BTDeviceList.REQUEST_CONNECT_BT);
}
else{

OutputStream opstream = null;
try {
opstream = btsocket.getOutputStream();
} catch (IOException e) {
e.printStackTrace();
}
btoutputstream = opstream;
print_bt();

}

}
private void print_bt() {
try {
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
e.printStackTrace();
}

btoutputstream = btsocket.getOutputStream();

byte[] printformat = { 0x1B, 0×21, FONT_TYPE };
btoutputstream.write(printformat);
String msg = message.getText().toString();
btoutputstream.write(msg.getBytes());
btoutputstream.write(0x0D);
btoutputstream.write(0x0D);
btoutputstream.write(0x0D);
btoutputstream.flush();
} catch (IOException e) {
e.printStackTrace();
}

}

@Override
protected void onDestroy() {
super.onDestroy();
try {
if(btsocket!= null){
btoutputstream.close();
btsocket.close();
btsocket = null;
}
} catch (IOException e) {
e.printStackTrace();
}
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
try {
btsocket = BTDeviceList.getSocket();
if(btsocket != null){
print_bt();
}

} catch (Exception e) {
e.printStackTrace();
}
}
}

第2步：

com.example.BlueToothPrinterApp/BTDeviceList.java

package com.example.BlueToothPrinterApp;

import java.io.IOException;
import java.util.Set;
import java.util.UUID;

import android.app.ListActivity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.bluetooth.BluetoothSocket;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Toast;
public class BTDeviceList extends ListActivity {

static public final int REQUEST_CONNECT_BT = 0×2300;

static private final int REQUEST_ENABLE_BT = 0×1000;

static private BluetoothAdapter mBluetoothAdapter = null;

static private ArrayAdapter<String> mArrayAdapter = null;

static private ArrayAdapter<BluetoothDevice> btDevices = null;

private static final UUID SPP_UUID = UUID
.fromString(“8ce255c0-200a-11e0-ac64-0800200c9a66″);
// UUID.fromString(“00001101-0000-1000-8000-00805F9B34FB”);

static private BluetoothSocket mbtSocket = null;

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);

setTitle(“Bluetooth Devices”);

try {
if (initDevicesList() != 0) {
this.finish();
return;
}

} catch (Exception ex) {
this.finish();
return;
}

IntentFilter btIntentFilter = new IntentFilter(
BluetoothDevice.ACTION_FOUND);
registerReceiver(mBTReceiver, btIntentFilter);
}

public static BluetoothSocket getSocket() {
return mbtSocket;
}

private void flushData() {
try {
if (mbtSocket != null) {
mbtSocket.close();
mbtSocket = null;
}

if (mBluetoothAdapter != null) {
mBluetoothAdapter.cancelDiscovery();
}

if (btDevices != null) {
btDevices.clear();
btDevices = null;
}

if (mArrayAdapter != null) {
mArrayAdapter.clear();
mArrayAdapter.notifyDataSetChanged();
mArrayAdapter.notifyDataSetInvalidated();
mArrayAdapter = null;
}

finalize();

} catch (Exception ex) {
} catch (Throwable e) {
}

}
private int initDevicesList() {

flushData();

mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if (mBluetoothAdapter == null) {
Toast.makeText(getApplicationContext(),
“Bluetooth not supported!!”, Toast.LENGTH_LONG).show();
return -1;
}

if (mBluetoothAdapter.isDiscovering()) {
mBluetoothAdapter.cancelDiscovery();
}

mArrayAdapter = new ArrayAdapter<String>(getApplicationContext(),
android.R.layout.simple_list_item_1);

setListAdapter(mArrayAdapter);

Intent enableBtIntent = new Intent(
BluetoothAdapter.ACTION_REQUEST_ENABLE);
try {
startActivityForResult(enableBtIntent, REQUEST_ENABLE_BT);
} catch (Exception ex) {
return -2;
}

Toast.makeText(getApplicationContext(),
“Getting all available Bluetooth Devices”, Toast.LENGTH_SHORT)
.show();

return 0;

}

@Override
protected void onActivityResult(int reqCode, int resultCode, Intent intent) {
super.onActivityResult(reqCode, resultCode, intent);

switch (reqCode) {
case REQUEST_ENABLE_BT:

if (resultCode == RESULT_OK) {
Set<BluetoothDevice> btDeviceList = mBluetoothAdapter
.getBondedDevices();
try {
if (btDeviceList.size() > 0) {

for (BluetoothDevice device : btDeviceList) {
if (btDeviceList.contains(device) == false) {

btDevices.add(device);

mArrayAdapter.add(device.getName() + “\n”
+ device.getAddress());
mArrayAdapter.notifyDataSetInvalidated();
}
}
}
} catch (Exception ex) {
}
}

break;
}

mBluetoothAdapter.startDiscovery();

}

private final BroadcastReceiver mBTReceiver = new BroadcastReceiver() {

@Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (BluetoothDevice.ACTION_FOUND.equals(action)) {
BluetoothDevice device = intent
.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);

try {
if (btDevices == null) {
btDevices = new ArrayAdapter<BluetoothDevice>(
getApplicationContext(), android.R.id.text1);
}

if (btDevices.getPosition(device) < 0) {
btDevices.add(device);
mArrayAdapter.add(device.getName() + “\n”
+ device.getAddress() + “\n” );
mArrayAdapter.notifyDataSetInvalidated();
}
} catch (Exception ex) {
// ex.fillInStackTrace();
}
}
}
};

@Override
protected void onListItemClick(ListView l, View v, final int position,
long id) {
super.onListItemClick(l, v, position, id);

if (mBluetoothAdapter == null) {
return;
}

if (mBluetoothAdapter.isDiscovering()) {
mBluetoothAdapter.cancelDiscovery();
}

Toast.makeText(
getApplicationContext(),
“Connecting to ” + btDevices.getItem(position).getName() + “,”
+ btDevices.getItem(position).getAddress(),
Toast.LENGTH_SHORT).show();

Thread connectThread = new Thread(new Runnable() {

@Override
public void run() {
try {
boolean gotuuid = btDevices.getItem(position)
.fetchUuidsWithSdp();
UUID uuid = btDevices.getItem(position).getUuids()[0]
.getUuid();
mbtSocket = btDevices.getItem(position)
.createRfcommSocketToServiceRecord(uuid);

mbtSocket.connect();
} catch (IOException ex) {
runOnUiThread(socketErrorRunnable);
try {
mbtSocket.close();
} catch (IOException e) {
// e.printStackTrace();
}
mbtSocket = null;
return;
} finally {
runOnUiThread(new Runnable() {

@Override
public void run() {
finish();

}
});
}
}
});

connectThread.start();
}

private Runnable socketErrorRunnable = new Runnable() {

@Override
public void run() {
Toast.makeText(getApplicationContext(),
“Cannot establish connection”, Toast.LENGTH_SHORT).show();
mBluetoothAdapter.startDiscovery();

}
};

@Override
public boolean onCreateOptionsMenu(Menu menu) {
super.onCreateOptionsMenu(menu);

menu.add(0, Menu.FIRST, Menu.NONE, “Refresh Scanning”);

return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
super.onOptionsItemSelected(item);

switch (item.getItemId()) {
case Menu.FIRST:
initDevicesList();
break;
}

return true;
}
}

第3步：

编辑main.xml文件并粘贴到代码下面。

RES /布局/ main.xml中

<?xml version=”1.0″ encoding=”utf-8″?>
<RelativeLayout xmlns:android=”http://schemas.android.com/apk/res/android&#8221;
android:layout_width=”fill_parent”
android:layout_height=”fill_parent”
android:paddingLeft=”16dp”
android:paddingRight=”16dp” >

  <TextView
    android:id="@+id/msgtextlbl"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="Enter Your Message : "/>

<EditText
    android:id="@+id/message"
    android:layout_width="fill_parent"
    android:layout_height="100dp"
    android:layout_below="@+id/msgtextlbl"
    android:text=""/>

<Button
    android:id="@+id/printButton"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:layout_below="@+id/message"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="5dip"
    android:text="Print"/>
</RelativeLayout>

第4步：

现在编辑AndroidManifest.xml

添加蓝牙权限和管理员权限。

的AndroidManifest.xml

<?xml version=”1.0″ encoding=”utf-8″?>
<manifest xmlns:android=”http://schemas.android.com/apk/res/android&#8221;
package=”com.example.BlueToothPrinterApp”
android:versionCode=”1″
android:versionName=”1.0″>
<application android:label=”@string/app_name” android:icon=”@drawable/ic_launcher”>
<activity android:name=”BlueToothPrinterApp”
android:label=”@string/app_name”>
<intent-filter>
<action android:name=”android.intent.action.MAIN” />
<category android:name=”android.intent.category.LAUNCHER” />
</intent-filter>
</activity>
<activity android:name=”BTDeviceList”></activity>
</application>
<uses-sdk android:minSdkVersion=”14″ />
<uses-permission android:name=”android.permission.BLUETOOTH”></uses-permission>
<uses-permission android:name=”android.permission.BLUETOOTH_ADMIN”></uses-permission>
</manifest>

编译并运行此应用程序。输入信息并按打印按钮。

您将看到蓝牙设备列表。选择bluettoth打印机。

检查蓝牙打印机上的打印件。

here is the CODE Reference...

Answer 2

您可以使用这个很棒的库，可以连接到任何打印机并轻松打印，

https://github.com/mazenrashed/Printooth

您可以通过以下方式下载它：

implementation 'com.github.mazenrashed:Printooth:${LAST_VERSION}'

并像这样使用它：

var printables = ArrayList<Printable>()
var printable = Printable.PrintableBuilder()  
.setText("Hello World")

printables.add(printable)

BluetoothPrinter.printer().print(printables)

如何在Android中通过蓝牙连接手机和打印机？

2 个答案: