Android系统中使用的打印框架是CUPS(Common Unix Printing System)。CUPS在打印时会使用一个缓存文件夹来存储打印任务的中间文件,而这些文件可以被视为Android系统中的“中间打印文件”。
以下是一个示例代码,用于在Android应用程序中打印一个文本文件,并获取中间文件的路径:
// Set up a print job with a file to print
PrintJob job = new PrintJob();
job.setPrintService(printService);
job.setJobName("My Printing Job");
PrintDocumentAdapter adapter = new PrintDocumentAdapter() {
@Override
public void onLayout(PrintAttributes oldAttributes, PrintAttributes newAttributes, CancellationSignal cancellationSignal, LayoutResultCallback callback, Bundle extras) {
// Respond to layout requests
}
@Override
public void onWrite(PageRange[] pages, ParcelFileDescriptor destination, CancellationSignal cancellationSignal, WriteResultCallback callback) {
// Write the document content to the destination file
FileInputStream input = new FileInputStream(fileToPrint);
FileOutputStream output = new FileOutputStream(destination.getFileDescriptor());
byte[] buf = new byte[1024];
int bytesRead;
try {
while ((bytesRead = input.read(buf)) > 0) {
output.write(buf, 0, bytesRead);
}
callback.onWriteFinished(new PageRange[]{PageRange.ALL_PAGES});
} catch (IOException e) {
Log.e(TAG, "Error printing file", e);
} finally {
try {
input.close();
output.close();
} catch (IOException e) {
Log.e(TAG, "Error closing streams", e);
}
}
}
};
PrintAttributes attributes = new PrintAttributes.Builder()
.setMediaSize(PrintAttributes.MediaSize.ISO_A4)
.setColorMode(PrintAttributes.COLOR_MODE_COLOR)
.setResolution(new PrintAttributes.Resolution("pdf", "pdf", 600, 600))
.setMinMargins(PrintAttributes.Margins.NO_MARGINS)
.build();
// Send the print job to the print service
PrintJobInfo info = job.createPrintJobInfo();
info.setAttributes(attributes);
info.setCopies(1);
printService.onPrintJobQueued(info);
// Get the path to the intermediate file
String cacheDir = getApplicationContext().getCacheDir().getAbsolutePath();
String jobId = info.getId().toString();
String filename = String.format("cups-job-%s.pdf", jobId);
String intermediateFilePath = String.format("%s/%s", cacheDir, filename);
此代码创建了一个打印作业,并将其