我已经制作了一个Android应用程序，我试图打印一个示例文本文件，我想使用wifi连接打印机，我试过这个链接Wifi printing in android但它只是搜索wifi打印机，什么都不做，我的代码如下，请帮助我，拯救我的生命
码
public class MainActivity extends Activity {
public int pageHeight;
public int pageWidth;
public PdfDocument myPdfDocument;
public int totalpages = 4;
Button button1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
button1 = (Button) findViewById(R.id.button1);
}
PrintDocumentAdapter pda = new PrintDocumentAdapter() {
@Override
public void onWrite(PageRange[] pages,
ParcelFileDescriptor destination,
CancellationSignal cancellationSignal,
WriteResultCallback callback) {
InputStream input = null;
OutputStream output = null;
try {
input = getAssets().open("sample.txt");
output = new FileOutputStream(destination.getFileDescriptor());
byte[] buf = new byte[1024];
int bytesRead;
while ((bytesRead = input.read(buf)) > 0) {
output.write(buf, 0, bytesRead);
}
callback.onWriteFinished(new PageRange[] { PageRange.ALL_PAGES });
} catch (FileNotFoundException ee) {
// Catch exception
} catch (Exception e) {
// Catch exception
} finally {
try {
input.close();
output.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
@SuppressLint("InlinedApi")
@Override
public void onLayout(PrintAttributes oldAttributes,
PrintAttributes newAttributes,
CancellationSignal cancellationSignal,
LayoutResultCallback callback, Bundle extras) {
if (cancellationSignal.isCanceled()) {
callback.onLayoutCancelled();
return;
}
//int pages = computePageCount(newAttributes);
PrintDocumentInfo pdi = new PrintDocumentInfo.Builder(
"Name of file").setContentType(
PrintDocumentInfo.CONTENT_TYPE_DOCUMENT).build();
callback.onLayoutFinished(pdi, true);
}
};
@SuppressLint("InlinedApi")
public void printDocument(View view) {
PrintManager printManager = (PrintManager) this
.getSystemService(Context.PRINT_SERVICE);
String jobName = this.getString(R.string.app_name) + " Document";
printManager.print(jobName, pda, null);
}
}
清单
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.wifiprint"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="21" />
<uses-feature android:name="android.hardware.wifi" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.CHANGE_WIFI_STATE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
答案 0 :(得分：0)
您应首先为按钮事件创建按钮侦听器。
Button button1 = (Button) findViewById(R.id.button1);
button1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
doCustomPrint();
}
});
这种自定义文档打印的打印方法;
private void doCustomPrint() {
PrintDocumentAdapter pda = new PrintDocumentAdapter(){
@Override
public void onWrite(PageRange[] pages, ParcelFileDescriptor destination, CancellationSignal cancellationSignal, WriteResultCallback callback){
InputStream input = null;
OutputStream output = null;
AssetManager assetManager = getAssets();
try {
// File for print.
input = assetManager.open("abc.pdf");
output = new FileOutputStream(destination.getFileDescriptor());
byte[] buf = new byte[1024];
int bytesRead;
while ((bytesRead = input.read(buf)) > 0) {
output.write(buf, 0, bytesRead);
}
callback.onWriteFinished(new PageRange[]{PageRange.ALL_PAGES});
} catch (FileNotFoundException ee){
//Catch exception
} catch (Exception e) {
//Catch exception
} finally {
try {
input.close();
output.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
@Override
public void onLayout(PrintAttributes oldAttributes, PrintAttributes newAttributes, CancellationSignal cancellationSignal, LayoutResultCallback callback, Bundle extras){
if (cancellationSignal.isCanceled()) {
callback.onLayoutCancelled();
return;
}
PrintDocumentInfo pdi = new PrintDocumentInfo.Builder("print_doc.pdf").setContentType(PrintDocumentInfo.CONTENT_TYPE_DOCUMENT).build();
callback.onLayoutFinished(pdi, true);
}
};
PrintManager printManager = (PrintManager) this.getSystemService(Context.PRINT_SERVICE);
String jobName = this.getString(R.string.app_name) + " Document";
printManager.print(jobName, pda, null);
}
并查看此文件。