Error during the installation of the application emulator "Calling the main entrance"

I use an Internet example to create a login system with PHP + Mysql. When I try to run the application, it does nothing and sends it back to me in the logcat.

2019-09-13 11: 31: 03.749 5897-5897 /? D / AndroidRuntime: >>>>>> START uid 2000 <<<<<< 2019-09-13
11: 31: 03.751 5897-5897 /? D / AndroidRuntime: CheckJNI is ON 2019-09-13
11: 31: 03.769 5897-5897 /? W / art: Unexpected CPU variant for X86 using
default values: x86 2019-09-13 11: 31: 03.772 5897-5897 /? D / ICU: No timezone
found substitution file: /data/misc/zoneinfo/current/icu/icu_tzdata.dat
2019-09-13 11: 31: 03.787 5897-5897 /? E / memtrack: Unable to load Memtrack
module (No such file or directory) 2019-09-13 11: 31: 03.787 5897-5897 /?
E / android.os.Debug: Memtrack module failed to load: -2 2019-09-13
11: 31: 03.787 5897-5897 /? I / Radio-JNI: register_android_hardware_Radio
FACT 2019-09-13 11: 31: 03.794 5897-5897 /? D / AndroidRuntime: Call
main entrance 2019-09-13 11: 31: 03.799
5897-5897 /? D / AndroidRuntime: Stopping the virtual machine

start activity code is this

package com.paquete;

import android.os.Bundle;
import android.widget.Button;
import android.widget.EditText;


import com.paquete.Utilidades.SessionHandler;

public class LoginActivity extends AppCompatActivity {

    private static final String KEY_STATUS = "status";
    private static final String KEY_MESSAGE = "message";
    private static final String KEY_FULL_NAME = "full_name";
    private static final String KEY_USERNAME = "username";
    private static final String KEY_PASSWORD = "password";
    private static final String KEY_EMPTY = "";
    private EditText etUsername;
    private EditText etPassword;
    private Button register, login;
    private String username;
    private String password;
    private ProgressDialog pDialog;
    private String login_url = "http://urllogin/login/login";
    private SessionHandler session;

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate( savedInstanceState );

        session = new SessionHandler(getApplicationContext());


        setContentView( R.layout.activity_login );

        etUsername = findViewById(;
        etPassword = findViewById(;

        register = findViewById(;
        login = findViewById(;

   //Launch Registration screen when Register Button is clicked
        register.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                Intent i = new Intent(LoginActivity.this, RegisterActivity.class);

        login.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                //Retrieve the data entered in the edit texts
                username = etUsername.getText().toString().toLowerCase().trim();
                password = etPassword.getText().toString().trim();
                if (validateInputs()) {


    private void loadDashboard() {
        Intent i = new Intent(getApplicationContext(), DashboardActivity.class);


    private void displayLoader() {
        pDialog = new ProgressDialog(LoginActivity.this);
        pDialog.setMessage("Logging In.. Please wait...");


    private void login() {
        JSONObject request = new JSONObject();
        try {
            //Populate the request parameters
            request.put(KEY_USERNAME, username);
            request.put(KEY_PASSWORD, password);

        } catch (JSONException e) {
        JsonObjectRequest jsArrayRequest = new JsonObjectRequest
                ( Request.Method.POST, login_url, request, new Response.Listener() {
                    public void onResponse(JSONObject response) {
                        try {
                            //Check if user got logged in successfully

                            if (response.getInt(KEY_STATUS) == 0) {

                                        response.getString(KEY_MESSAGE), Toast.LENGTH_SHORT).show();

                        } catch (JSONException e) {
                }, new Response.ErrorListener() {

                    public void onErrorResponse(VolleyError error) {

                        //Display error message whenever an error occurs
                                error.getMessage(), Toast.LENGTH_SHORT).show();


        // Access the RequestQueue through your singleton class.

    private boolean validateInputs() {
            etUsername.setError("Username cannot be empty");
            return false;
            etPassword.setError("Password cannot be empty");
            return false;
        return true;


The manifest.xml file looked like this




ruby – move as many lines of # code out of the main line as possible

How can I move the lines of code out of the main if possible?
without messing up the program. Please, ask me if you have not underestimated the question. Thank you

def main
  a_file ="mydata.txt", "w") # open for writing
  if a_file  # if nil this test will be false
    puts "Unable to open file to write!"

  a_file ="mydata.txt", "r") # open for reading
  if a_file  # if nil this test will be false
    puts "Unable to open file to read!"


htaccess redirects from the subdomain directory to the main domain

I need to redirect all requests from a subdomain-specific directory to the main domain.


need to redirect to

(only redirects requests with directory directory)

Can I be the main source of funding for a UK visitor visa as a student?

I am an Egyptian student.
I wish to apply for a short term UK visitor visa. I am an independent freelancer-seller eBay, while being a student at the same time. My eBay earnings are transferred to my account each month. In most cases, students indicate in the visa application that it is their parents who will pay for their trip while they are non-active students, but this would not be the case for me. I will mention that I will finance my own trip myself. I will not mention my parents as a source of funding in the application, so I will not include any documents indicating their financial situation with my application. I will simply add my own bank statement and paypal statement. Would this be accepted by the Embassy to issue my visa? What are my chances?
For registrations, I have two schengen visas before for italy and belgium, i do not know if they could help us!

linux – Expand CentOS partition – Have 4 main partitions

I have a CentOS server that acts as a syslog server (CentOS Linux version 7.4.1708 (Core)). As my syslog grew, we had to increase the volume several times. Now the main disk is 500 GB. We have recently increased the size of VMWare up to 800 GB. I have followed this excellent document -the-size-of-a-linux-lvm-by-expanding-the-virtual-machine disk /.

This is what my record looks like:

fdisk -l

Disk /dev/sda: 859.0 GB, 858993459200 bytes, 1677721600 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk label type: dos
Disk identifier: 0x000a207b

   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048     1026047      512000   83  Linux
/dev/sda2         1026048    62914559    30944256   8e  Linux LVM
/dev/sda3        62914560   524287999   230686720   83  Linux
/dev/sda4       524288000   943718399   209715200   8e  Linux LVM


fd0               2:0    1     4K  0 disk 
sda               8:0    0   800G  0 disk 
├─sda1            8:1    0   500M  0 part /boot
├─sda2            8:2    0  29.5G  0 part 
│ ├─centos-root 253:0    0 447.5G  0 lvm  /
│ └─centos-swap 253:1    0     2G  0 lvm  (SWAP)
├─sda3            8:3    0   220G  0 part 
│ └─centos-root 253:0    0 447.5G  0 lvm  /
└─sda4            8:4    0   200G  0 part 
  └─centos-root 253:0    0 447.5G  0 lvm  /
sr0              11:0    1  1024M  0 rom  

When trying to create a new partition, I receive the following error message:

If you want to create more than four partitions, you must replace a primary partition with an extended partition first.

It seems that I have reached the limit of 4 main partitions. I'm trying to determine my options. Is it possible to expand on this new 300GB without formatting the drive? Can I convert one of my current primary partitions to an extended partition without destroying my data? Any help would be greatly appreciated!


trees – How to find the method of division and conquest of complexity at the time of execution without the main theorem

I understand that the main theorem can be used to solve divide and conquer analysis times if they come in the form: $ T (n) = aT ( frac {n} {b}) + n ^ obstruction ^ k (n) $ The reason behind this is to draw a tree of subroutines and see how each k level behaves, right?

Suppose now that your divide and conquer algorithm can be described as follows:

$ T (n) = T ( frac {n} {2}) + 1.5 ^ n $

I guess it's $ theta (1.5 ^ n) $ simply because it seems that this term dominates, but my hypothesis is not logical. How would you find great theta at this task?

My attempt to find the answer was to draw the first levels of the tree by looking for:

Level 1: $ T (n) = 1.5 ^ n $

Level 2: $ T (n) = 1.5 ^ { frac {n} {2}} $

Level 3: $ T (n) = 1.5 ^ { frac {n} {4}} $

So it seems that for level k (from 1), the task turns out to be 1.5 $ ^ { frac {n} {2 ^ {k-1}}} $

So, as the number of levels increases, it seems that the time required to complete the task decreases by a factor of 2?

Any help is welcome! Tips are preferable, but if you want to provide the complete answer, that's fine too.

nikon – How to identify the main subject of the photo and set the focus?

Well, I can not say the same for your Nikon model, but if you have a live view, you can zoom in and check the details of your subject. I suggest trying manual focus, because the autofocus cameras does not identify the focus on objects without contrasting edges, such as rotating disk of the saw above.

Also, if you want to become more familiar with your camera, try not to use the preset modes and use the Aperture Priority, Shutter Priority, Program, and Manual options. You can start with Program, the mode closest to the automatic mode, while allowing you to choose the settings.

For your current problem, I suggest using the aperture mode and increasing the aperture between f6 and f8, which will increase the depth of field so that more subject is in focus and, in case your focus would go away a bit, the depth of field will make it less visible

Modify the main search form to also search the user

I do not know if it is possible, I would like to modify the main search to also allow search by user profile …
I've only found a solution for a separate search.

The configurable image resolution is not the same as the main image in 2.3.1 magenta

I've created a configurable product based on colors. In my theme, I can change the resolution of the image by setting it manually from the backend. I set it to 1200×1800. When I try to upload an image, its resolution is set correctly but when downloading an image by color, it always comes default to 800×1200.Therefore, the picture is blurry when I select a different color from the drop-down menu of the website.

magento2.3 – How to make sure that minicart reflects the updated product image for the article in the (main) basket?

We use the product designer that allows the user to change the product image. While the new image (based on what the user is changing) is correctly displayed according to the themes basket pages, the mini-cart does not display the updated image. I see that default.phtml references

app / design / frontend / Smartwave // ​​Magento_Checkout / templates / cart / item / default.phtml (line 29)

getImage ($ block-> getProductForThumbnail (), & # 39; cart_page_product_thumbnail & # 39;) -> toHtml (); ?>

How can we make sure that the minicart reflects the updated image for the (main) basket article?

thank you so much