I am working on an application where I am connecting with the BLE device and sending commands.
One of that commands we have a command for changing the Bluetooth device name.
Communication is working fine, but the problem is when we send the command for changing the name it was working, BLE confirms the input and sends us the output, but when we disconnect and run LE Scan it was showing the same name as the previous, it should show the new name of the device.
If I want to get the latest name of the device I need to open the Bluetooth page manually in the device and scan over there in the scan result it was showing the latest name, when I open the app again which is in the background and its scanning under LE scan function with 10-sec delay, it was showing the new name in the list.
How can I ask Bluetooth manager or system to refresh the cache or refresh data for that Bluetooth device ?.
I don't know it was right to create ticket, but i have created ticket in google issue tracker : https://issuetracker.google.com/issues/233924346
Thanks.
I had the same problem and solved it by reading the new name from the raw scan data. In this way you never have to use device.getName() which returns the old name from the cache. This is Android Java code for the scan callback function.
private ScanCallback newscancallback()
{
ScanCallback scb;
// Device scan callback.
scb = new ScanCallback()
{
#Override
public void onScanResult(int callbackType, ScanResult result)
{
super.onScanResult(callbackType, result);
int n,k,len,getout;
BluetoothDevice dev;
byte[] rec;
StringBuilder nameb;
String name;
dev = result.getDevice();
// do not use dev.getName() which returns cached name
// read current name from raw scan record instead
name = null;
rec = result.getScanRecord().getBytes();
len = rec.length;
nameb = new StringBuilder();
n = 0;
getout = 0;
// search scan record for name
while(n < len-2 && rec[n] != 0 && getout == 0)
{
// rec[n] is length of next item
// rec[n+1] is item type - look for 8 or 9=name
// rec[n+2].. is the name, length rec[n]-1
if(rec[n] > 1 && (rec[n+1] == 8 || rec[n+1] == 9)
{ // found name
for(k = 0 ; k < rec[n]-1 ; ++k)
nameb.append((char)rec[n+2+k]);
name = nameb.toString();
getout = 1;
}
else // go to next item
n += rec[n] + 1;
}
// name is now null or the new name from the scan record
}
#Override
public void onScanFailed(int errcode)
{
}
#Override
public void onBatchScanResults(List<ScanResult> result)
{
}
};
return (scb);
}
As you can see the latest name in the Bluetooth settings of the mobile device, I believe there is no issue with the Bluetooth manager of the system. The issue will be in the scanning function of the code as it is not actually refreshing the scan list yet and it might saved the last known BLE list somewhere in the cache. If you are using third-party library, you might need to check their documentation or codes about how the scan function actually works. There may be like force-refresh option or something in the library. As far as I know, to save the device's battery, there is a delay to actually refresh the scan list.
Related
Hello this is my method to get the used mobile data for every installed application in an android phone but it only get me the data used by my app not all the apps
I need it to get the data mobile used by every app installed in the phone
void OthernetworkUsage() {
List<PackageInfo> packs = getPackageManager().getInstalledPackages(PackageManager.GET_PERMISSIONS);
for(PackageInfo p : packs){
// if(!isSystemPackage(p)){
if(usesInternet(p)) {
long received = TrafficStats.getUidRxBytes(p.applicationInfo.uid);
long sent = TrafficStats.getUidTxBytes(p.applicationInfo.uid);
String appName = p.applicationInfo.loadLabel(getPackageManager()).toString();
int uid = p.applicationInfo.uid;
Toast.makeText(this, "uid: "+uid+"/Kb - name: "+appName+": Sent = "+sent/1024+"Kb, Rcvd = "+received/1024+"Kb", Toast.LENGTH_SHORT).show();
}
//}
}
}
I really need help in that case.
I have a Hp LaserJet Cp1025nw Color printer. I am able to print with wireless but with when I connected with USB cable(OTG) I am not able to print.
The Device is showing an adapter like that which are disabled USB: HP LaserJet CP 1025nw
I am using Samsung Galaxy A Tablet
The Spinner of Printer from the Hp printer SDK
AppCompatSpinner sizeSpinner = (AppCompatSpinner) findViewById(R.id.paper_size_spinner);
List<String> spinnerList = new ArrayList<String>();
// add 4x5 as needed
String text = "";
if (PrintUtil.is4x5media) {
text = (String) getText(R.string.preview_spinner_4x5);
spinnerMap.put(text, PrintAttributes.MediaSize.NA_INDEX_4X6);
spinnerList.add(text);
}
// add default media size
for (int i = 0; i < defaultMediaSizes.length; i++) {
text = getSpinnerText(defaultMediaSizes[i]);
spinnerMap.put(text, defaultMediaSizes[i]);
spinnerList.add(text);
}
// add media size in print items
if(printJobData.getPrintItems() != null)
for (PrintAttributes.MediaSize mediaSize: printJobData.getPrintItems().keySet()) {
text = getSpinnerText(mediaSize);
if (!spinnerList.contains(text)) {
spinnerMap.put(text, mediaSize);
spinnerList.add(text);
}
}
// add media size from default print item if it does exist
if (printJobData.getDefaultPrintItem() != null && printJobData.getDefaultPrintItem().getMediaSize() != null) {
PrintAttributes.MediaSize mediaSize = printJobData.getDefaultPrintItem().getMediaSize();
text = getSpinnerText(mediaSize);
if (!spinnerList.contains(text)) {
spinnerMap.put(text, mediaSize);
spinnerList.add(text);
}
}
String[] spinnerArray = spinnerList.toArray(new String[spinnerList.size()]);
ArrayAdapter<String> adapter = new ArrayAdapter<>(this,android.R.layout.simple_spinner_item, spinnerArray);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
sizeSpinner.setAdapter(adapter);
if(printJobData.getPrintDialogOptions() != null) {
PrintAttributes.MediaSize mediaSize = printJobData.getPrintDialogOptions().getMediaSize();
text = getSpinnerText(mediaSize);
sizeSpinner.setSelection(adapter.getPosition(text));
}
setSizeSpinnerListener(sizeSpinner);
Has anyone faced this problem? Please Mention the solution if any.
The disabled printers you're seeing are the Wireless ones (looks like you've printed with and hence they became favorite and would show up even if they are not in range/disoverable).
To my knowledge the HP Print Plugin does not discover printers over USB cables, but you can confirm that (or request the feature) with the app support.
I am working on an android app used to access a Box account. The problem I am facing is how to determine a folder/file in the user's account is read only (shared with him/her as a Viewer) so that the upload/delete operations can be disabled.
What I currently do is:
1) Get the items in a folder:
BoxCollection itemsCollection = _boxClient.getFoldersManager()
.getFolderItems(folderId, folderContentRequest);
String userMail = ...
ArrayList<BoxTypedObject> result = null;
2) Determine which one is folder, get it's collaborations, check if it's accessible by the logged-in user, and check whether he is an editor:
if (itemsCollection != null) {
result = itemsCollection.getEntries();
for(BoxTypedObject boxObject : result) {
if(boxObject instanceof BoxAndroidFolder) {
BoxAndroidFolder folder = (BoxAndroidFolder)boxObject;
List<BoxCollaboration> folderCollaborations = _boxClient.getFoldersManager().getFolderCollaborations(folder.getId(), null);
for(BoxCollaboration collaboration : folderCollaborations) {
if( userMail.equalsIgnoreCase(collaboration.getAccessibleBy().getLogin()) &&
!BoxCollaborationRole.EDITOR.equalsIgnoreCase(collaboration.getRole()))
System.out.println("" + folder.getName() + " is readonly");
}
}
}
}
So, is there a simpler and faster (fewer requests) way to get that property of a folder with the android SDK?
You can first check the owner of the folder (folder.getOwnedBy()), if it's the current user then you don't need to check collaborations. However if it's not the current user you'll have to check collaborations.
I want to openOrCreate database in SDcard / Media Card. When i run the application in device (BlackBerry Curve 8900), i find only one root i.e "system/" and running application in simulator (9500), i find three roots as shown in comment in code. I am getting error at;
_db = DatabaseFactory.openOrCreate(_uri);
(error: Method "toString" with signature "()Ljava/lang/String;" is not applicable on this object)
And i am not able to understand what is this error about.
Here is the code.
public void getValues() throws Exception
{
boolean sdCardPresent = false;
String root = null;
Enumeration e = FileSystemRegistry.listRoots();
while (e.hasMoreElements())
{
root = (String)e.nextElement();
System.out.println("Value of root::" +root); // value of root = "system/" when run in device and
// value of root = "store/" "SDCard/" "system/" when run in simulator
if(root.equalsIgnoreCase("system/"))
{
sdCardPresent = true;
}
}
System.out.println("--------------------getValues()----------------------------------");
URI _uri = URI.create(Global.DB_PATH + Global.DB_Main);
System.out.println("Valud of uri::" +_uri);
_db = DatabaseFactory.openOrCreate(_uri); //getting error here.
System.out.println("Valud of _db::" +_db);
_db.close();
I tried these three paths, getting output with "/store"(when run in simulator) but error with rest two paths.Even using "/store" in device is showing the same error.
Global.DB_PATH = "/MediaCard/databases/";
Global.DB_PATH = "/SDCard/databases/";
Global.DB_PATH = "/store/databases/";
Is there any way how to get SDCard/Media Card as root so that i can copy the database in there?
My guess is when you are running your app on a real device you have USB cable plugged in to the device. If this is the case, try to unplug the cable and rerun the app. You may use Dialog.inform() to quickly check what roots you get this time.
private ObjectListField getFileList() {
if (fileList == null) {
fileList = new ObjectListField();
String[] roots = new String[3];
Enumeration enum = FileSystemRegistry.listRoots();
int x = 0;
while (enum.hasMoreElements()) {
if (x < 3) {
roots[x] = enum.nextElement().toString();
}
x++;
}
enum = FileSystemRegistry.listRoots();
fileList.set((roots[2] != null) ? roots : new String[]{"system/", "SDCard/", "store/"});
}
return fileList;
}
Try this code.
I know it's possible to get the local device name as described in the solution to this question Display Android Bluetooth Device Name
What I'm interested in knowing is, can I change the local buetooth name (the one other devices see when I'm in discovery mode) programaticlly. I know you can change it by hand, but I'm writing and app and I want to be able to change the name (add a simple flag) so other devices with the same application can scan and instantly know if the phone is also running the app.
tl;dr: How can I change the bluetooth device name on android?
Yes you can change your device name using setName(String name) of BluetoothAdapter type.Following is the sample code:
private BluetoothAdapter bluetoothAdapter = null;
bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
void ChangeDeviceName(){
Log.i(LOG, "localdevicename : "+bluetoothAdapter.getName()+" localdeviceAddress : "+bluetoothAdapter.getAddress());
bluetoothAdapter.setName("NewDeviceName");
Log.i(LOG, "localdevicename : "+bluetoothAdapter.getName()+" localdeviceAddress : "+bluetoothAdapter.getAddress());
}
Thanks for the original answer, here are a few things I found when implementing that might help someone else out.
1) BT has to be enabled for setName() to work.
2) It takes time for BT to Enable. ie. you Can't just call enable() then setName()
3) It takes time for the name to "sink in". ie. you can't call getName() right after setName() and expect the new name.
So, here is a snippet of code I came up with to use a runnable to get the job done in the background. It is also time bound to 10seconds, so it won't run forever if there is a problem.
Finally, this is part of our power on check, and we normally leave BT disabled (due to battery). So, I turn BT back off after, you may not want to do that.
// BT Rename
//
final String sNewName = "Syntactics";
final BluetoothAdapter myBTAdapter = BluetoothAdapter.getDefaultAdapter();
final long lTimeToGiveUp_ms = System.currentTimeMillis() + 10000;
if (myBTAdapter != null)
{
String sOldName = myBTAdapter.getName();
if (sOldName.equalsIgnoreCase(sNewName) == false)
{
final Handler myTimerHandler = new Handler();
myBTAdapter.enable();
myTimerHandler.postDelayed(
new Runnable()
{
#Override
public void run()
{
if (myBTAdapter.isEnabled())
{
myBTAdapter.setName(sNewName);
if (sNewName.equalsIgnoreCase(myBTAdapter.getName()))
{
Log.i(TAG_MODULE, "Updated BT Name to " + myBTAdapter.getName());
myBTAdapter.disable();
}
}
if ((sNewName.equalsIgnoreCase(myBTAdapter.getName()) == false) && (System.currentTimeMillis() < lTimeToGiveUp_ms))
{
myTimerHandler.postDelayed(this, 500);
if (myBTAdapter.isEnabled())
Log.i(TAG_MODULE, "Update BT Name: waiting on BT Enable");
else
Log.i(TAG_MODULE, "Update BT Name: waiting for Name (" + sNewName + ") to set in");
}
}
} , 500);
}
}
To change the bluetooth name properly you need to take care of following things:
1) You need following permissions:
android.permission.BLUETOOTH
android.permission.BLUETOOTH_ADMIN
2) Check the bluetooth state from adapter as you can only change the name of bluetooth is turned on.
val bluetoothAdapter = BluetoothAdapter.getDefaultAdapter();
if(bluetoothAdapter.state == BluetoothAdapter.STATE_ON){
bluetoothAdapter.setName("NewDeviceName");
}
3) If the bluetooth is not turned on then you can turn it on with the following command:
bluetoothAdapter.enable()
4) Last thing, please don't use static timers to wait for bluetooth state changes instead the proper way is that you can register for android.bluetooth.adapter.action.STATE_CHANGED broadcast and useBluetoothAdapter.EXTRA_STATE to get the new state of bluetooth whenever it is changed.
Note: Not all devices behave the same when it comes to bluetooth and changing the name due to caching and hw address, so never expect same outcome from all devices.