Android无线连接打印第三方开发的实现

         最近在做关于Android的项目，Android果然不是出于国内，很多东西都是国外已经成熟了或者已经开发好了，国内去效仿。为了找关于Android无线连接打印机并打印的第三方开发方案都非常的困难。由于最近项目需要用到这一块，经过我的组员的努力，找到了一种解决方案，为了能够和大家分享一下，也为了自己以后的参考，在这里稍作总结一下。经验有限，希望有更好方案的可以不吝赐教，我也会在以后的学习中不断修缮自己的方案。

        为了便于大家的参考，本文涉及到的所有的相关工程文件都在本人的csdn下载部分有相关资料下载。

       1.背景：

               很多开发者在工作上或者学习中可能需要通过基于Android系统的手机或者平板终端连接打印机，并驱动打

       印机打印自己发送的图片或者文本。本篇博客主要致力于解决这个问题。

       2.方案：

               本方案需要在android系统中安装一个软件send2print，在我的csdn下载频道中有相应的中文破解版下载链

        接，然后再写自己的程序，来调用其接口进行打印。事先需要在send2print中配置好默认打印机，我们写的程序

        就是调用其默认打印机进行无线打印。

       3.send2print：（我的csdn下载：http://download.csdn.net/detail/kunlong0909/4514502）

                这个软件可以安装直接使用，可以搜索开着无线的打印机，并连接进行打印，目前只有国外有卖该产品，

        国内网上可以下载汉化版，我的csdn下载中也有。汉化版有一定的缺陷，经过测试，佳能产品的大部分型号

        都无法实现打印，但是HP LaserJet 1536dnf MFP可以实现打印。

        4.代码实现：（我的csdn工程源码下载：http://download.csdn.net/detail/kunlong0909/4514570）

               我也不想贴代码，但是，安装好之后，配置上默认打印机，你只需要两个类就可以轻松实现无线打印了，

        由于代码量不大，也很容易看懂，我就直接贴在下面了，如果需要测试打印的资源文件可以到我csdn下载频道

        下载，这该死的博客怎么没有直接上传资源功能，还是我没有发现啊，谁发现了告诉我一声啊，嘿嘿。

                PrintUtils.java

               

package com.rcreations.testprint;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.io.OutputStream;import android.app.Activity;import android.app.AlertDialog;import android.content.Context;import android.content.DialogInterface;import android.content.Intent;import android.content.pm.PackageInfo;import android.content.pm.PackageManager;import android.graphics.Bitmap;import android.graphics.Picture;import android.net.Uri;import android.os.Environment;import android.util.Log;public class PrintUtils{// for loggingprivate static final StringTAG= PrintUtils.class.getSimpleName();// Send 2 Printer package nameprivate static final String PACKAGE_NAME = "com.rcreations.send2printer";// intent action to trigger printingpublic static final String PRINT_ACTION = "com.rcreations.send2printer.print";// content provider for accessing images on local sdcard from within html content// sample img src shoul be something like "content://s2p_localfile/sdcard/logo.gif"public static final String LOCAL_SDCARD_CONTENT_PROVIDER_PREFIX = "content://s2p_localfile";/** * Returns true if "Send 2 Printer" is installed.  */public static boolean isSend2PrinterInstalled( Context context ){boolean output = false;PackageManager pm = context.getPackageManager();        try {             PackageInfo pi = pm.getPackageInfo( PACKAGE_NAME, 0 );            if( pi != null )            {            output = true;            }        } catch (PackageManager.NameNotFoundException e) {}        return output;}/** * Launches the Android Market page for installing "Send 2 Printer" * and calls "finish()" on the given activity. */public static void launchMarketPageForSend2Printer( final Activity context ){        AlertDialog dlg = new AlertDialog.Builder( context )        .setTitle("Install Send 2 Printer")        .setMessage("Before you can print to a network printer, you need to install Send 2 Printer from the Android Market.")        .setPositiveButton( android.R.string.ok, new DialogInterface.OnClickListener() {@Overridepublic void onClick( DialogInterface dialog, int which ){// launch browserUri data = Uri.parse( "http://market.android.com/search?q=pname:" + PACKAGE_NAME );Intent intent = new Intent( android.content.Intent.ACTION_VIEW, data );intent.setFlags( Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TOP );context.startActivity( intent );// exitcontext.finish();}        } )        .show();}    /**     * Save the given picture (contains canvas draw commands) to a file for printing.     */    public static File saveCanvasPictureToTempFile( Picture picture )    {    File tempFile = null;            // save to temporary file    File dir = getTempDir();    if( dir != null )    {FileOutputStream fos = null;try{File f = File.createTempFile( "picture", ".stream", dir );fos = new FileOutputStream( f );picture.writeToStream( fos );tempFile = f;}catch( IOException e ){Log.e( TAG, "failed to save picture", e );}finally{close( fos );}    }        return tempFile;    }            /**     * Sends the given picture file (returned from {@link #saveCanvasPictureToTempFile}) for printing.     */    public static boolean queuePictureStreamForPrinting( Context context, File f )    {    // send to print activity    Uri uri = Uri.fromFile( f );    Intent i = new Intent( PRINT_ACTION );    i.setDataAndType( uri, "application/x-android-picture-stream" );    i.putExtra( "scaleFitToPage", true );    context.startActivity( i );        return true;    }            /**     * Save the given Bitmap to a file for printing.     * Note: Bitmap can be result of canvas draw commands.     */    public static File saveBitmapToTempFile( Bitmap b, Bitmap.CompressFormat format )    throws IOException, UnknownFormatException    {    File tempFile = null;            // save to temporary file    File dir = getTempDir();    if( dir != null )    {FileOutputStream fos = null;try{String strExt = null;switch( format ){case PNG:strExt = ".pngx";break;case JPEG:strExt = ".jpgx";break;default:throw new UnknownFormatException( "unknown format: " + format );}File f = File.createTempFile( "bitmap", strExt, dir );fos = new FileOutputStream( f );b.compress( format, 100, fos );tempFile = f;}finally{close( fos );}    }        return tempFile;    }            /**     * Sends the given image file for printing.     */    public static boolean queueBitmapForPrinting( Context context, File f, Bitmap.CompressFormat format )    throws UnknownFormatException    {    String strMimeType = null;switch( format ){case PNG:strMimeType = "image/png";break;case JPEG:strMimeType = "image/jpeg";break;default:throw new UnknownFormatException( "unknown format: " + format );}        // send to print activity    Uri uri = Uri.fromFile( f );    Intent i = new Intent( PRINT_ACTION );    i.setDataAndType( uri, strMimeType );    i.putExtra( "scaleFitToPage", true );    i.putExtra( "deleteAfterPrint", true );    context.startActivity( i );        return true;    }        /**     * Sends the given text for printing.     */    public static boolean queueTextForPrinting( Context context, String strContent )    {    // send to print activity    Intent i = new Intent( PRINT_ACTION );    i.setType( "text/plain" );    i.putExtra( Intent.EXTRA_TEXT, strContent );    context.startActivity( i );        return true;    }                /**     * Save the given text to a file for printing.     */    public static File saveTextToTempFile( String text )    throws IOException    {    File tempFile = null;            // save to temporary file    File dir = getTempDir();    if( dir != null )    {FileOutputStream fos = null;try{File f = File.createTempFile( "text", ".txt", dir );fos = new FileOutputStream( f );fos.write( text.getBytes() );tempFile = f;}finally{close( fos );}    }        return tempFile;    }            /**     * Sends the given text file for printing.     */    public static boolean queueTextFileForPrinting( Context context, File f )    {    // send to print activity    Uri uri = Uri.fromFile( f );    Intent i = new Intent( PRINT_ACTION );    i.setDataAndType( uri, "text/plain" );    i.putExtra( "deleteAfterPrint", true );    context.startActivity( i );        return true;    }            /**     * Sends the given html for printing.     *      * You can also reference a local image on your sdcard using the "content://s2p_localfile" provider.     * For example: <img src="content://s2p_localfile/sdcard/logo.gif">     */    public static boolean queueHtmlForPrinting( Context context, String strContent )    {    // send to print activity    Intent i = new Intent( PRINT_ACTION );    i.setType( "text/html" );    i.putExtra( Intent.EXTRA_TEXT, strContent );    context.startActivity( i );        return true;    }                /**     * Sends the given html URL for printing.     *      * You can also reference a local file on your sdcard using the "content://s2p_localfile" provider.     * For example: "content://s2p_localfile/sdcard/test.html"     */    public static boolean queueHtmlUrlForPrinting( Context context, String strUrl )    {    // send to print activity    Intent i = new Intent( PRINT_ACTION );    //i.setDataAndType( Uri.parse(strUrl), "text/html" );// this crashes!    i.setType( "text/html" );    i.putExtra( Intent.EXTRA_TEXT, strUrl );    context.startActivity( i );        return true;    }                /**     * Save the given html content to a file for printing.     */    public static File saveHtmlToTempFile( String html )    throws IOException    {    File tempFile = null;            // save to temporary file    File dir = getTempDir();    if( dir != null )    {FileOutputStream fos = null;try{File f = File.createTempFile( "html", ".html", dir );fos = new FileOutputStream( f );fos.write( html.getBytes() );tempFile = f;}finally{close( fos );}    }        return tempFile;    }            /**     * Sends the given html file for printing.     */    public static boolean queueHtmlFileForPrinting( Context context, File f )    {    // send to print activity    Uri uri = Uri.fromFile( f );    Intent i = new Intent( PRINT_ACTION );    i.setDataAndType( uri, "text/html" );    i.putExtra( "deleteAfterPrint", true );    context.startActivity( i );        return true;    }        /** * Return a temporary directory on the sdcard where files can be saved for printing. * @return null if temporary directory could not be created. */public static File getTempDir(){File dir = new File( Environment.getExternalStorageDirectory(), "temp" );if( dir.exists() == false && dir.mkdirs() == false ){Log.e( TAG, "failed to get/create temp directory" );return null;}return dir;}        /**     * Helper method to close given output stream ignoring any exceptions.     */    public static void close( OutputStream os )    {        if( os != null )        {            try            {                os.close();            }            catch( IOException e ) {}        }    }        /**     * Thrown by bitmap methods where the given Bitmap.CompressFormat value is unknown.     */    public static class UnknownFormatException extends Exception    {    public UnknownFormatException( String msg )    {    super( msg );    }    }}

             以上是工具类，下面的是测试类：

         MainActivity.java

       

package com.rcreations.testprint;import java.io.File;import android.app.Activity;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.graphics.Canvas;import android.graphics.Paint;import android.graphics.Picture;import android.graphics.Rect;import android.graphics.Typeface;import android.os.Bundle;import android.util.Log;import android.view.View;import android.widget.Button;/** * Various print samples. */public class MainActivity extends Activity{private static final StringTAG= MainActivity.class.getSimpleName();static final String HELLO_WORLD = "Hello World";/**     * Called when the activity is first created.     */    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);        //        // check for and install Send 2 Printer if needed        //                if( PrintUtils.isSend2PrinterInstalled(this) == false )        {        PrintUtils.launchMarketPageForSend2Printer( this );        return;        }                //        // setup GUI buttons        //                Button btnTestCanvas = (Button)findViewById( R.id.btnTestCanvas );        btnTestCanvas.setOnClickListener( new View.OnClickListener() {@Overridepublic void onClick(View v){printCanvasExample();}        });                Button btnTestCanvasAsBitmap = (Button)findViewById( R.id.btnTestCanvasAsBitmap );        btnTestCanvasAsBitmap.setOnClickListener( new View.OnClickListener() {@Overridepublic void onClick(View v){printCanvasAsBitmapExample();}        });        Button btnTestText = (Button)findViewById( R.id.btnTestText );        btnTestText.setOnClickListener( new View.OnClickListener() {@Overridepublic void onClick(View v){printTextExample();}        });        Button btnTestHtml = (Button)findViewById( R.id.btnTestHtml );        btnTestHtml.setOnClickListener( new View.OnClickListener() {@Overridepublic void onClick(View v){printHtmlExample();}        });                Button btnTestHtmlUrl = (Button)findViewById( R.id.btnTestHtmlUrl );        btnTestHtmlUrl.setOnClickListener( new View.OnClickListener() {@Overridepublic void onClick(View v){printHtmlUrlExample();}        });                Button btnTestTextFile = (Button)findViewById( R.id.btnTestTextFile );        btnTestTextFile.setOnClickListener( new View.OnClickListener() {@Overridepublic void onClick(View v){printTextFileExample();}        });        Button btnTestHtmlFile = (Button)findViewById( R.id.btnTestHtmlFile );        btnTestHtmlFile.setOnClickListener( new View.OnClickListener() {@Overridepublic void onClick(View v){printHtmlFileExample();}        });    }         /**     * Send canvas draw commands for printing.     * NOTE: Android 1.5 does not properly support drawBitmap() serialize/deserialize across process boundaries.     * If you need to draw bitmaps, then see the {@link #printCanvasAsBitmapExample()} example.      */    void printCanvasExample()    {    // create canvas to render on    Picture picture = new Picture();    Canvas c = picture.beginRecording( 240, 240 );        // fill background with WHITE    c.drawRGB( 0xFF, 0xFF, 0xFF );        // draw text    Paint p = new Paint();    Typeface font = Typeface.create(Typeface.SANS_SERIF, Typeface.BOLD);        p.setTextSize( 18 );        p.setTypeface( font );        p.setAntiAlias(true);         Rect textBounds = new Rect();    p.getTextBounds( HELLO_WORLD, 0, HELLO_WORLD.length(), textBounds );    int x = (c.getWidth() - (textBounds.right-textBounds.left)) / 2;    int y = (c.getHeight() - (textBounds.bottom-textBounds.top)) / 2;    c.drawText( HELLO_WORLD, x, y, p );        // draw icon    Bitmap icon = BitmapFactory.decodeResource( getResources(), R.drawable.icon );    c.drawBitmap( icon, 0, 0, null );    // stop drawing    picture.endRecording();        // queue canvas for printing    File f = PrintUtils.saveCanvasPictureToTempFile( picture );    if( f != null )    {    PrintUtils.queuePictureStreamForPrinting( this, f );    }    }            /**     * Draw to a bitmap and then send the bitmap for printing.     */    void printCanvasAsBitmapExample()    {    // create canvas to render on    Bitmap b = Bitmap.createBitmap( 240, 240, Bitmap.Config.RGB_565 );    Canvas c = new Canvas( b );        // fill background with WHITE    c.drawRGB( 0xFF, 0xFF, 0xFF );        // draw text    Paint p = new Paint();    Typeface font = Typeface.create(Typeface.SANS_SERIF, Typeface.BOLD);        p.setTextSize( 18 );        p.setTypeface( font );        p.setAntiAlias(true);         Rect textBounds = new Rect();    p.getTextBounds( HELLO_WORLD, 0, HELLO_WORLD.length(), textBounds );    int x = (c.getWidth() - (textBounds.right-textBounds.left)) / 2;    int y = (c.getHeight() - (textBounds.bottom-textBounds.top)) / 2;    c.drawText( HELLO_WORLD, x, y, p );        // draw icon    Bitmap icon = BitmapFactory.decodeResource( getResources(), R.drawable.icon );    c.drawBitmap( icon, 0, 0, null );    // queue bitmap for printing    try    {    File f = PrintUtils.saveBitmapToTempFile( b, Bitmap.CompressFormat.PNG );    if( f != null )    {    PrintUtils.queueBitmapForPrinting( this, f, Bitmap.CompressFormat.PNG );    }    }    catch( Exception e )    {    Log.e( TAG, "failed to save/queue bitmap", e );    }    }            /**     * Send text for printing.     */    void printTextExample()    {PrintUtils.queueTextForPrinting( this, HELLO_WORLD );    }            /**     * Send html for printing.     */    void printHtmlExample()    {StringBuilder buf = new StringBuilder();buf.append( "<html>" );buf.append( "<body>" );buf.append( "<h1>" ).append( HELLO_WORLD ).append( "</h1>" );    buf.append( "<p>" ).append( "blah blah blah..." ).append( "</p>" );  buf.append( "<p><img src=\"http://www.google.com/intl/en_ALL/images/logo.gif\" /></p>" );// you can also reference a local image on your sdcard using the "content://s2p_localfile" provider (see below) //buf.append( "<p><img src=\"content://s2p_localfile/sdcard/logo.gif\" /></p>" );buf.append( "</body>" );    buf.append( "</html>" );PrintUtils.queueHtmlForPrinting( this, buf.toString() );    }            /**     * Send html URL for printing.     */    void printHtmlUrlExample()    {PrintUtils.queueHtmlUrlForPrinting( this, "http://www.google.com" );    }            /**     * Send text file for printing.     */    void printTextFileExample()    {    try    {    File f = PrintUtils.saveTextToTempFile( HELLO_WORLD );    if( f != null )    {    PrintUtils.queueTextFileForPrinting( this, f );    }    }    catch( Exception e )    {    Log.e( TAG, "failed to save/queue text", e );    }    }            /**     * Send html file for printing.     */    void printHtmlFileExample()    {    try    {    StringBuilder buf = new StringBuilder();    buf.append( "<html>" );    buf.append( "<body>" );    buf.append( "<h1>" ).append( HELLO_WORLD ).append( "</h1>" );        buf.append( "<p>" ).append( "blah blah blah..." ).append( "</p>" );      buf.append( "<p><img src=\"http://www.google.com/intl/en_ALL/images/logo.gif\" /></p>" );    // you can also reference a local image on your sdcard using the "content://s2p_localfile" provider (see below)     //buf.append( "<p><img src=\"content://s2p_localfile/sdcard/logo.gif\" /></p>" );    buf.append( "</body>" );        buf.append( "</html>" );        File f = PrintUtils.saveHtmlToTempFile( buf.toString() );    if( f != null )    {    PrintUtils.queueHtmlFileForPrinting( this, f );    }    }    catch( Exception e )    {    Log.e( TAG, "failed to save/queue html", e );    }    }        }

        其实整体上的逻辑很简单，连接无线打印机和驱动打印都是通过send2printer来实现的，我们只是需要调用它，将我们需要打印的信息发送给它就行，so easy！