在Android中,使用PrintManager来设置打印机通常涉及以下几个步骤:
获取PrintManager实例:
首先,你需要获取一个PrintManager的实例。这通常在Activity或Fragment的onCreate
方法中完成。
PrintManager printManager = (PrintManager) getSystemService(Context.PRINT_SERVICE);
创建打印任务:
使用PrintManager创建一个打印任务。你可以通过调用printManager.printText()
、printManager.printDocument()
或printManager.printBitmap()
等方法来创建打印任务。
String textToPrint = "Hello, World!";
PrintDocumentInfo printDocumentInfo = new PrintDocumentInfo.Builder("My Document")
.setContentType(PrintDocumentInfo.CONTENT_TYPE_TEXT)
.build();
PrintDocument printDocument = new PrintDocument() {
@Override
public void onWrite(PrintWriter writer) throws IOException {
writer.println(textToPrint);
}
@Override
public void onLayout(PrintAttributes oldAttributes, PrintAttributes newAttributes, Rect bounds, Rect[] pages, int pageCount) {
// 处理布局逻辑
}
};
printManager.printDocument(printDocumentInfo, printDocument, new PrintCallback() {
@Override
public void onCompletion(PrintJobInfo printJobInfo) {
super.onCompletion(printJobInfo);
Toast.makeText(YourActivity.this, "Printing completed", Toast.LENGTH_SHORT).show();
}
});
选择打印机:
如果你想让用户选择一个打印机,可以使用printManager.printFromSelection()
方法。这个方法会弹出一个选择打印机的对话框。
printManager.printFromSelection(new String[]{"com.example.myapp.MyDocument"}, null, null, null);
设置打印机属性:
你可以通过PrintAttributes
对象来设置打印机的属性,例如页边距、字体等。
PrintAttributes.Builder builder = new PrintAttributes.Builder();
builder.setMediaSize(PrintAttributes.MEDIA_SIZE_A4);
builder.setResolution(PrintAttributes.RESOLUTION_DEFAULT);
builder.setColorMode(PrintAttributes.COLOR_MODE_MONOCHROME);
PrintAttributes printAttributes = builder.build();
printManager.print(printDocumentInfo, printDocument, null, printAttributes);
处理打印错误:
在打印过程中可能会发生错误,你可以通过实现PrintCallback
接口来处理这些错误。
printManager.print(printDocumentInfo, printDocument, new PrintCallback() {
@Override
public void onStartDocument(PrintJobInfo printJobInfo, boolean autoClose) {
super.onStartDocument(printJobInfo, autoClose);
}
@Override
public void onError(PrintJobInfo printJobInfo, PrintException error) {
super.onError(printJobInfo, error);
Toast.makeText(YourActivity.this, "Printing failed: " + error.getMessage(), Toast.LENGTH_LONG).show();
}
@Override
public void onFinishDocument(PrintJobInfo printJobInfo, boolean autoClose) {
super.onFinishDocument(printJobInfo, autoClose);
}
@Override
public void onWrite(PrintWriter writer) throws IOException {
writer.println(textToPrint);
}
@Override
public void onLayout(PrintAttributes oldAttributes, PrintAttributes newAttributes, Rect bounds, Rect[] pages, int pageCount) {
// 处理布局逻辑
}
});
通过以上步骤,你可以在Android应用中使用PrintManager来设置和打印文档。