How to fix the problem with error "No virtual method" on android

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• Read each name in Array list to create seperate object for

  I have a file that has student names, age, and an id number. I have a student class that holds the everything above for each student object. I stored all the names, id numbers. and age separately in an array list. Now im trying to assign the info to create a student object.

  public class Student {
      private String lName;
      private int idNumber;
      private int age;
  
      public Student() {
          lName = "";
          idNumber = 0;
          age = 0;
      }
      public Student(String l, int i, int a) {
          lName = l;
          idNumber = i;
          age = a;
      }
  
      public void setName(String last) {
          lName = last;
      }
  
      public String getName() {
          return lName;
      }
  
      public void setIdNum(int num) {
          idNumber = num;
      }
  
      public int getIdNum() {
          return idNumber;
      }
  
      public void setAge(int a) {
          age = a;
      }
  
      public int getAge() {
          return age;
      }
  }
  

  My Text File looks something like this: This info is stored in parallel array lists. I don't quite get how to implement this into an object to pass it into my second contractor method.

    Josh          2134         19
    Smith         5256         21
    Rogers        9248         19
    Andrew        7742         20
  

  Here's what I've tried;

  public static void main(String[] args) {
      String file = "studentData.txt";
      Scanner reader = new Scanner(file);
  
      ArrayList<String> lastNames = lNames(file);
      ArrayList<Integer> idNumbers = idNum(file);
      ArrayList<Integer> ageList = ages(file);
  
      Scanner input = new Scanner(System.in);
  
      Student s1 = new Student();
  
      // confused about how to implement this constructor with the textile info
      for (int i = 0; i<idNumbers.size(); i++) {
          Student user = new Student(lastNames.get(i), idNumbers.get(i), ageList.get(i));
      }
  
      //user enters idNumber to display age
      System.out.println("Enter ID Number"); //exception handling to be added
      int idNum = input.nextInt();
  
      for (int i = 0; i<idNumbers.size(); i++) {
          if (idNum == idNumbers.get(i)) {
              s1.setAge(ageList.get(i));
              System.out.println(s1.getAge());
  
          }
      }
  }
  
• Using EdittextPreference for Goto search

  sorry for my poor English. I want to use EditTextPreference in my bottom nav like the pic below, ![screenshot][1]

  I have recycleview xml in my project with in many sub cardview layouts(which is scrollable) and I want to create item in the bottom nav which is called "Goto". When the "Goto" item is clicked i want it to pop-up like the screenshot. And when user enters a number(according to the cardviews i.e if the number of cardview is 40 user must enter 1-40) I want to search the cardview by its ID. Thank you and I hope u got it, If u have any questions let me know [1]: https://i.stack.imgur.com/grK8P.jpg

  My xml format look like this. As you see in the blow since the cardviews are huge in number it is not cool to scroll all the way down that is why i need Goto item in the bottom nav to search it by its ID when the user click number in the EditTextPreference as u see in the screenshot. i.e The screenshot is not from my app

  <LinearLayout>
   <LinearLayout>
    <androidx.cardview.widget.CardView>
      <RealtiveLayout>
         <Textview/>
      <RealtiveLayout>
   </androidx.cardview.widget.CardView>
   </LinearLayout>
  
   <LinearLayout>
    <androidx.cardview.widget.CardView>
      <RealtiveLayout>
         <Textview/>
      <RealtiveLayout>
   </androidx.cardview.widget.CardView>
   </LinearLayout>
  
  <LinearLayout>
    <androidx.cardview.widget.CardView>
      <RealtiveLayout>
         <Textview/>
      <RealtiveLayout>
   </androidx.cardview.widget.CardView>
   </LinearLayout>
  
    <LinearLayout>
    <androidx.cardview.widget.CardView>
      <RealtiveLayout>
         <Textview/>
      <RealtiveLayout>
   </androidx.cardview.widget.CardView>
   </LinearLayout>
   
    ..
    ..
  
    ..
    ..
    many more..
  
• How to get remaining time of the day in java?

  I would like to calculate the time remaining for next day 00:00:00 from the current date time.

  For e.g. time difference between 2022-05-07T05:49:41.883807900Z and 2022-05-08T00:00:00Z

  Expected answer: 18:10:19 or 65419 (in seconds).

  How can I achieve this with efficiently using java 8?
• Updating a Single Column In Room Database

  That's the function I'm using for updat

  private fun updateSettingsDatabase(settingsDao: SettingsDao) {
          lifecycleScope.launch {
              settingsDao.update(SettingsEntity(
                  1,
                  nightMode=nightModeResult,
              ))
          }
  }
  
  @Query("SELECT * FROM `settings-table`")
  fun fetchCurrentSettings(): Flow<List<SettingsEntity>>
  

  I specified nightMode= because I thought that this way I'm only updating this colummn, but it turns out that it resets every column, how do I update a single column, while keeping the values the rest of the columns?
• IOS Launcher in android studio

  I'm trying to change the whole Android OS installed app icons into IOS icons, please help me with the proper code or library for android kotlin
• different between call view by name or use binding in android

  i'am a newest in android kotlin

  I want to know what is the difference between the two lines of code below and which one is better to use

  class MainActivity : AppCompatActivity() {
  private lateinit var binding: ActivityMaindinding
  
  override fun onCreate(savedInstanceState: Bundle?) {
      super.onCreate(savedInstanceState)
      bindins = DataBindingutil.setContentview( this, R.layout.activity_main)
  
  
          textview.text="text"//or
  
          binding.textview.text="text"
  }}
  
• Get multiple times current time on single Button

  I have a button showing text START when I click on it I shows me current time in textview.(I consider this time as start time). Than convert the text on Button into STOP. When I click on it again show me current time on another textview(I consider this time as stop time). And then calculate the difference between these two time. I want this same working for multiple time. I means First button show Text ENTER. When I click on it it should show current time in textview.(I will consider this time as Enter time). Than convert the text on Button into START. When I click on it again show me current time on another textview(I will consider this time as start time). Than convert the text on Button into STOP. When I click on it again show me current time on another textview(I will consider this time as STOP time). And last Than convert the text on Button into EXIT. When I click on it again show me current time on another textview(I will consider this time as Exit time).

  Here is my code:

   btn_start.setOnClickListener(new View.OnClickListener() {
              @Override
              public void onClick(View v) {
  
                  if (isStarted){
                      Calendar calendar = Calendar.getInstance();
                      SimpleDateFormat format = new SimpleDateFormat("hh:mm:ss aa");
                      String time = format.format(calendar.getTime());
  
  
                      tvend.setText(time);
                      try {
                          Date date1 = format.parse(tvend.getText().toString());
                          Date date2 = format.parse(tvstarttime.getText().toString());
                          long mills = date1.getTime() - date2.getTime();
                          Log.v("Data1", ""+date1.getTime());
                          Log.v("Data2", ""+date2.getTime());
                          int hours = (int) (mills/(1000 * 60 * 60));
                          int mins = (int) (mills % (1000*60*60));
  
                          String diff = hours + ":" + mins;
                          diffence.setText(diff);
                      } catch (ParseException e) {
                          e.printStackTrace();
                      }
                      btn_start.setText("START");
                  }else {
                      Calendar calendar = Calendar.getInstance();
                      SimpleDateFormat format = new SimpleDateFormat("hh:mm:ss aa");
                      String time1 = format.format(calendar.getTime());
  
  
                      tvstarttime.setText(time1);
                      btn_start.setText("STOP");
                  }
                  isStarted = !isStarted;
  
  
  
              }
          });
  
  
  
  
• android emulator disable microphone when launching device

  How do we disable the (virtual) microphone when launching the emulator?

  Situation
  When launching an Android Studio stock emulator device, the microphone is always enabled and listening.

  Why would we want this fix

  • Convenience, Many users have a microphone headset and when the microphone is enabled, they lose noise canceling and/or stereo. It can be extremely annoying, forcing the user to disconnect the device which swaps the emulator audio + sounds to another microphone/speaker input/output.
  • Security risk, the microphone is actively listening. Is the data going anywhere? Who knows...this is an unnecessary security risk for any organization, IE a dev is on a (zoom, teams, meetings) call with an open emulator that is using the microphone and listening).

  Possible Solutions (based on practicality)

  1. flag to disable virtual audio devices (IE the mac's speaker or attached headphones w/ a microphone). I've seen 0 documentation regarding a flag like this.
  2. flag to provide to the emulator to disable all audio input (see answer 1). TLDR add the flag -no-audio
  3. route the android studio emulator (or the mac's microphone audio input) to a virtual device that is not listening. Or have the default OS microphone input set to 0 volume. This can be done via macOSX Automator
  4. route the adb emulator to the mac's internal microphone instead of the current microphone to avoid it triggering the headsets microphone settings.

  The preferred solution

  • Microphone audio-in is disabled when booting the emulator
  • Android device audio-out remains and uses the computer's default speakers
  • The computer's default microphone is not triggered (at all) to avoid causing a stereo -> mono swap or noise cancellation breakage.

  System Information:

  • android emulator: 31.2.10.0
  • MacOS 12.3.1
  • Headsets tested with these issues:
    • Bose NC 700
    • Bose QC series
    • Sony WF-1000XM4
    • Sony WH-1000XM3
    • any headset with a microphone connection macro that does something with the speaker (like talk through) or with the input audio like stereo -> mono.
• Force 2.4GHz WiFi on Android 11

  I have a phone with Android 11 and I want it to connect to the 2.4GHz band of the WiFi. The WiFi has both the 2.4GHz and 5GHz band with the same SSID. I am working on some testing which requires me to not change any settings on the router. Is it possible to have the phone get connected to the 2.4GHz band and not the 5GHz band? Previously, Android had options to select the band in Advanced WiFi settings, but it is not present right now and I cannot have two SSIDs for the 2 bands.
• Trying to get a Pi (with Volumio) to connect to my wifi hotspot

  So I know this is involved with the Volumio OS, but I was hoping to reach any proficient Linux/Pi users that know how to mess with the supplicant.conf file and things I should look for when connecting a Pi to my phones hotspot. I don't get a lot of help on Volumio forums, I have my CCNA, and know some coding methods. I really want to get my home project working, so that's why I'm asking here.

  I basically have not been able to get my pi to connect to only my hotspot. Currently it works if I have my hotspot on, and connect to my home wifi. I used journtalctl commands and found something that looks weird:

  When I connect to my phone hotspot, I see it goes through the handshake steps, checks for the proper key, it says “connected to: Pixel 5”, “key negotiation completed”, “send eapol packet, recv eapol packet”, Once it gets to association it says " association success", Then: “rtw_cfg80211_indicates_connect(wlan0) BSS not found !!” then it has another association success, with it basically looking like it fails saying “Trying to associate with (instert my AP MAC ADDR)” I have not been able to use Wireshark but I think it's failing to associate. Is that what this looks like? I’ve never had an association issue before. Another weird thing is when I command “sudo iwconfig” it says “security mode: open” not sure if that is supposed to show my wifi encryption method instead?

  It's really late so, tomorrow I will borrow a friends phone, because I'm not sure it's working completely with my phone.
• Saved video not showing in gallery android 9

  I am storing video in internal storage but the saved video is not showing up in gallery. To see that first i have to open my file manager then come back to gallery. I stored the same video in android Q using media store but in

                          ContentResolver contentResolver = getContentResolver();
                          ContentValues contentValues = new ContentValues();
                          contentValues.put(MediaStore.MediaColumns.DISPLAY_NAME, "videoFileName");
                          contentValues.put(MediaStore.MediaColumns.MIME_TYPE, "video/mp4");
                          contentValues.put(MediaStore.MediaColumns.RELATIVE_PATH, Environment.DIRECTORY_MOVIES);
                          Uri finalUriPath = contentResolver.insert(MediaStore.Video.Media.EXTERNAL_CONTENT_URI, contentValues);
                          File sourceLocation = new File(finalUri.getPath());
                      
                          InputStream in = new FileInputStream(sourceLocation);
                          FileOutputStream out = new FileOutputStream(String.valueOf(finalUriPath));
                          byte[] buf = new byte[1024];
                          int len;
                          while ((len = in.read(buf)) > 0) {
                              out.write(buf, 0, len);
                          }
                          in.close();
                          out.close();
                          contentValues.clear();
                          contentValues.put(MediaStore.Video.Media.IS_PENDING, 0);
  
                          StatusShowerActivity.this.getContentResolver().update(finalUriPath, contentValues, null, null);
                          Toast.makeText(StatusShowerActivity.this, "Saved", Toast.LENGTH_SHORT).show();
  

  Exception got from Catch in android 9

   java.io.FileNotFoundException: null (Read-only file system)
  
• Android API 28 getBitmap throwing "no such column" error

  On Android API 28, I'm trying to get the album art for a particular album using the albumID. The code throws the following error on getBitmap

  android.database.sqlite.SQLiteException: no such column: _data (code 1 SQLITE_ERROR): , while compiling: SELECT _data FROM album_info WHERE (id=?)
  

  The code below:

  Uri imageUri_t = ContentUris.withAppendedId(MediaStore.Audio.Albums.EXTERNAL_CONTENT_URI, albumID);
  origImage = MediaStore.Images.Media.getBitmap(contentResolver, imageUri_t);
  

  The albumID is collected earlier using a cursor query to get the MediaStore.Audio.AudioColumns.ALBUM_ID column. I also tried with MediaStore.Audio.Albums_ID, but the same result happens.

  It's worth noting that it works fine in API 29 and 30 using the newer loadThumnail introduced in API 29

  origImage = contentResolver.loadThumbnail(imageUri_t, new android.util.Size(256, 256), null);
  
• Android 9 Screen Rotation Approach

  Our team has recently updated a system application (installed in priv-app) from Android 5 to Android 9. This seems to have broken the previously working (and relatively well documented approach) of programmatically flipping the device orientation.

  We had been using this approach and it had worked at globablly flipping the device orientation 180 degrees:

  Settings.System.putInt( context.getApplicationContext().getContentResolver(), Settings.System.USER_ROTATION, 2)
  

  We check each time to make sure the accelerometer rotation is disabled also. The setting does in fact stick as when interrogate the settings provider and can see the value being updated, the screen is simply not reacting, even after a reboot etc..

  I'm trying to understand if Android 9 introduced any further gotchas that can prevent a screen rotation from happening, would be grateful if anyone had any insight on this particular issue?