Develop Reference

Android printing with Brother SDK via WiFi throws ERROR_WRONG_LABEL despite selecting correct labelNameIndex

I've been trying to print with Brother Print SDK 3.5.1 on Android 8.1.0. I keep getting ERROR_WRONG_LABEL.
This is the code I use
void printPdf() {
// Specify printer
final Printer printer = new Printer();
PrinterInfo settings = printer.getPrinterInfo();
settings.printerModel = PrinterInfo.Model.QL_810W;
settings.port = PrinterInfo.Port.NET;
settings.ipAddress = "192.168.1.73";
settings.workPath = "storage/emulated/0/Download/";
// Print Settings
settings.labelNameIndex = LabelInfo.QL700.W62RB.ordinal();
settings.printMode = PrinterInfo.PrintMode.FIT_TO_PAGE;
settings.orientation = PrinterInfo.Orientation.PORTRAIT;
settings.isAutoCut = true;
printer.setPrinterInfo(settings);
// Connect, then print
new Thread(new Runnable() {
#Override
public void run() {
if (printer.startCommunication()) {
PrinterStatus result = printer.printPdfFile("/storage/emulated/0/Download/hello world red.pdf", 1);
if (result.errorCode != PrinterInfo.ErrorCode.ERROR_NONE) {
Log.d("TAG", "ERROR - " + result.errorCode);
}
printer.endCommunication();
}
}
}).start();
}
My printer model is QL-810W and I use the black and red W62 roll.
I've tried the Sample Application, where setting W62RB in labelNameIndex prints fine.
Changing the roll for different one with different width didn't help.
I've also tried iterating over numbers 0 to 50 and using them as labelNameIndex.
Based on this thread, I thought that the issue may be in specifying the workPath attribute. Setting workPath to getContext().getCacheDir().getPath() results in ERROR_OUT_OF_MEMORY instead of ERROR_WRONG_LABEL. Not specifying workPath and adding <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/> to AndroidManifest.xml results in ERROR_WRONG_LABEL
EDIT
I've modified the Brother Sample app and uploaded it to GitHub. The app now launches Activity_PrintPdf.java by default where I inserted my printing code with hardcoded values at the beginning of onCreate method - this works fine and prints the PDF file as expected.
Then I created a new Empty Activity project in Android Studio, copy pasted the library, added the imports to build.gradle and copy pasted the permissions into AndroidManifest.xml. Then I copy pasted the printing code at the beginning of onCreate method in MainActivity.java. Running the app results in ERROR_WRONG_LABEL.
This is the modified working example app and this is the one that results in the error. I want to use the code as native module that I call from my React Native app, so it's important that I manage to set up the printing code from scratch rather than modifying the existing example app.
EDIT 2
I've inspected the library with a debugger: when executing printer.setPrinterInfo(mPrinterInfo) the library internally calls private boolean createWorkPath(String dirPath) of Printer object. On return from this method, the debugger shows Source code doesn't match the bytecode and seems to forget the created directory. This also internally sets mResult.errorCode = ErrorCode.ERROR_WORKPATH_NOT_SET. However, instead of rising any error here the code just silently proceeds, which later results in ERROR_WRONG_LABEL when trying to print. Running the same code snipper in the modified Sample app works fine.
I'd be grateful if you could help or suggest what to try next.
Thank you!

I've now fixed the issue, which was that the Brother library silently failed to create a temporarily folder and instead of reporting an error, it continued and failed later to read the label information. Based on this thread, it is now required to specify runtime file read and write permissions as opposed to the compile-time ones in AndroidManifest.xml.
Adding
ActivityCompat.requestPermissions(this,
new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},1);
at the beginning of onCreate before the printing code fixed the issue.

Android instrumentation tests fail on Google's Test Lab Galaxy S9+ due to keyboard on-boarding popup

Occasionally, the instrumentation tests (Espresso) are failing on Google's Firebase Test Lab due to a keyboard on-boarding popup (screenshot) that blocks the screen and prevents tap/type events.
This only happens on the Samsung Galaxy S9+
Here is the exception:
android.support.test.espresso.PerformException: Error performing 'type text(666666)' on view '(is descendant of a: (with id: XXX) and an instance of android.widget.EditText)'.
Caused by: android.support.test.espresso.InjectEventSecurityException: java.lang.SecurityException: Injecting to another application requires INJECT_EVENTS permission
at android.support.test.espresso.base.InputManagerEventInjectionStrategy.injectKeyEvent(InputManagerEventInjectionStrategy.java:113)
Any suggestions?

Maybe you can try to play around with "ime" command from ADB to enable another keyboard (you can log for example the return of ime list in order to get the IDs) before running your tests (e.g. #Before):
getInstrumentation().getUiAutomation().executeShellCommand("ime enable ID");
Thread.sleep(1000);
getInstrumentation().getUiAutomation().executeShellCommand("ime set ID");
Else you can workaround with uiautomator and implement a check before using the keyboard with this kind of piece of code :
...
onView(withId(R.id.inputField)).perform(click());
if (Build.VERSION.SDK_INT >= 23) {
UiDevice device = UiDevice.getInstance(getInstrumentation());
UiObject skipButton = device.findObject(new UiSelector().text("SKIP"));
if (skipButton.exists()) {
try {
skipButton.click();
Timber.e(e, "Dismissed popup on Keyboard");
} catch (UiObjectNotFoundException e) {
Timber.e(e, "There is no popup displayed on Keyboard");
}
}
}
onView(withId(R.id.inputField)).perform(typeText("some"), pressImeActionButton());
...
Hope this help !

I also faced this problem. It's on Firebase Test Lab side, and you shouldn't try to find a workaround. Sometimes there are problems with devices you are not responsible for. Instead you should report about it to Firebase team directly if you want it to be fixed as soon as possible.
The fastest way to do it is to go to #test-lab channel of the Firebase Slack community and report them about an issue like that. They will ask you to provide your matrix ID where you experienced something wrong.
As for layout popup, it was fixed the next day it was reported, so you shouldn't see it now.

How to enable Android Open Application voice interaction

According to the system voice command docs, you can open an application with a voice command. e.g. OK Google - open foobar. Also according to the docs, this Works by default; no specific intent.
In my sample development app, this isn't working. I've tried adding a few combinations of action and category permutations to the intent-filter, but no luck so far.
I'm targeting a minimum SDK of 23, testing on a device with 6.0.1.
Should this work, and if so, what are the changes to a new empty activity project I need to enable it?

As far as I am aware, Google simply iterates over a list of installed applications and opens the corresponding application if it finds an exact match.
To test this, use the following Intent
final String PACKAGE_NAME_GOOGLE_NOW = "com.google.android.googlequicksearchbox";
final String GOOGLE_NOW_SEARCH_ACTIVITY = ".SearchActivity";
final String APP_NAME = "Open " +getString(R.string.app_name);
final Intent startMyAppIntent = new Intent(Intent.ACTION_WEB_SEARCH);
startMyAppIntent.setComponent(new ComponentName(PACKAGE_NAME_GOOGLE_NOW,
PACKAGE_NAME_GOOGLE_NOW + GOOGLE_NOW_SEARCH_ACTIVITY));
startMyAppIntent.putExtra(SearchManager.QUERY, APP_NAME);
startMyAppIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
try {
startActivity(startMyAppIntent);
} catch (final ActivityNotFoundException e) {
e.printStackTrace();
}
If this opens your application, then it is simply a case of the phonetics of your application name, or how Google interprets your pronunciation of it.
I do think that there should be an option to add a 'phonetic app label' to the application's manifest (or some other globally available configuration file), so Google could open your application if the unique name is not common enough to generate a voice search result.
If this doesn't open your application, check that you are correctly defining your application name in the manifest as follows:
<application
android:label="#string/app_name"

Viewing logcat in tablet

Is there a way to view the log on a tablet running 4.4? I've downloaded several apps like aLogCat and none of them show what my app writes out with S.o.p or Log.d. I have an intermittent bug that gives the Unfortunately appname has stopped message.Is there any way to view the log after this event without having to connect to a PC and use the adb program?
What other ways are there to get debug output? Would trapping the System.out and System.err classes get the stack trace?
Thanks,
Norm

You're focussing on tring to read out logcat, but there are better solutions for reading crash logs. My personal preference is Crashlytics, which automatically logs fatal exceptions and provides mechanisms for logging other messages.
The way all these crash reporters work, is by defining a UncaughtExceptionHandler:
Thread.setDefaultUncaughtExceptionHandler(
new MyUncaughtExceptionHandler(this));
If you prefer to use your own solution, you may want to look into using this. See this related question for more details.

Is there a way to view the log on a tablet running 4.4?
No, sorry. An app can only see its own log messages, not those from other apps. Hence, a third-party log viewer cannot see your app's messages.
Is there any way to view the log after this event without having to connect to a PC and use the adb program?
Use any standard crash management library, like ACRA, or services like Crashlytics, BugSense, etc.

The AIDE Application (Android Integrated Development Environment) allows one to develop android Apps directly on android device.
One particular feature is to read the logcat.
You can get it here https://play.google.com/store/apps/details?id=com.aide.ui

Here's the code I've put in the program. It seems to work:
// Define inner class to handle exceptions
class MyExceptionHandler implements Thread.UncaughtExceptionHandler {
public void uncaughtException(Thread t, Throwable e){
java.util.Date dt = new java.util.Date();
String fn = LogFilePathPfx + "exception_" + sdf.format(dt) + ".txt";
try{
PrintStream ps = new PrintStream( fn );
e.printStackTrace(ps);
ps.close();
System.out.println("wrote trace to " + fn);
e.printStackTrace(); // capture here also???
SaveStdOutput.stop(); // close here vs calling flush() in class
}catch(Exception x){
x.printStackTrace();
}
lastUEH.uncaughtException(t, e); // call last one Gives: "Unfortunately ... stopped" message
return; //???? what to do here
}
}
lastUEH = Thread.getDefaultUncaughtExceptionHandler(); // save previous one
Thread.setDefaultUncaughtExceptionHandler(new MyExceptionHandler());

preparing SMS app for Android KitKat

in agreement with the recent post from Android Developers http://android-developers.blogspot.pt/2013/10/getting-your-sms-apps-ready-for-kitkat.html ,I was trying to prepare my app to the new android version, but encountered a problem with the part they suggest to create a dialog to let the user set the app as the default application to handle SMS's :
Android Developers Post
public class ComposeSmsActivity extends Activity {
#Override
protected void onResume() {
super.onResume();
final String myPackageName = getPackageName();
if (!Telephony.Sms.getDefaultSmsPackage(this).equals(myPackageName)) {
// App is not default.
// Show the "not currently set as the default SMS app" interface
View viewGroup = findViewById(R.id.not_default_app);
viewGroup.setVisibility(View.VISIBLE);
// Set up a button that allows the user to change the default SMS app
Button button = (Button) findViewById(R.id.change_default_app);
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Intent intent =
new Intent(Telephony.Sms.Intents.ACTION_CHANGE_DEFAULT);
intent.putExtra(Telephony.Sms.Intents.EXTRA_PACKAGE_NAME,
myPackageName);
startActivity(intent);
}
});
} else {
// App is the default.
// Hide the "not currently set as the default SMS app" interface
View viewGroup = findViewById(R.id.not_default_app);
viewGroup.setVisibility(View.GONE);
}
}
}
the code itself in pretty much straightforward, but I'm unable to access to Telephony.Sms.getDefaultSmsPackage because it says that Telephony cannot be resolved, and I can't find any import or declaration that would fix that.
Can anyone please help?

android.provider.Telephony simply doesn't exist yet (as of API 18 - 4.3).
This class will be added in 4.4 (presumably API 19), and that blog post is highlighting the changes that you should make once the new API is released so you aren't surprised when the time comes.
From the end of the post:
To help you make the changes, we'll soon be providing the necessary SDK components for Android 4.4 that allow you to compile and test your changes on Android 4.4.
Don't forget that you should wrap this code in an API version check so you don't run into issues with older versions that don't have this class.

this change will break all the SMS blocking apps.
"Note that—beginning with Android 4.4—any attempt by your app to abort the SMS_RECEIVED_ACTION broadcast will be ignored so all apps interested have the chance to receive it."
Do you think there is a way to go around this?!
Maybe at least on Root?

Apparently there is with root access. The latest version Cerberus app claim to be doing this.
Now, if only I knew how they do it :(