java - app-debuk.apk停止工作

Question

我是Android编程的新手，这是我在Gradle的第一个项目。过去，我使用Maven for Java。因此，我使用Android Studio制作了一个应用程序，如果我单击，请运行并选择我的手机，它将构建并安装apk到我的手机中，然后自动打开并运行正常。

因此，我想与一位 friend 分享我的进度，因此我单击了 Make Project ，它在 /app/build/outputs/apk/app-debug.apk中生成了 app-debug.apk ，但是如果我尝试安装该应用程序，请在启动后使用以下文本关闭自身的应用程序强制:“不幸的是，该应用程序停止了的工作”。

这是我的 build.gradle (Module:app):



和我的 build.gradle (项目:Autosiskola):

错误代码:
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.androidports.autosiskola/com.androidports.‌​autosiskola.MainActi‌​vity}: java.lang.ClassNotFoundException: Didn't find class "com.androidports.autosiskola.MainActivity" on path: DexPathList[[zip file "/data/app/com.androidports.autosiskola-1/base.apk"],nativeL‌​ibraryDirectories=[/‌​data/app/com.android‌​ports.autosiskola-1/‌​lib/arm64, /vendor/lib64, /system/lib64]]
我的主要 Activity :

    package com.androidports.autosiskola;

import android.content.Intent;
import android.os.AsyncTask;
import android.os.StrictMode;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ProgressBar;

import android.widget.Toast;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class MainActivity extends AppCompatActivity {

EditText username, password;
Button login;
ProgressBar progressBar;

Connection conn = null;
PreparedStatement pst = null;
ResultSet rs = null;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
    StrictMode.setThreadPolicy(policy);

    username = (EditText) findViewById(R.id.txtUsername);
    password = (EditText) findViewById(R.id.txtPassword);

    login = (Button) findViewById(R.id.btnLogin);

    progressBar = (ProgressBar) findViewById(R.id.progressBar);
    progressBar.setVisibility(View.GONE);

    conn = DBConnect.Connector();

    login.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            if (username.toString().trim().isEmpty() && password.toString().isEmpty()) {
                Toast.makeText(MainActivity.this, "Nincs felhasználónév / jelszó megadva!", Toast.LENGTH_SHORT).show();
            } else {
                switch (v.getId()) {
                    case R.id.btnLogin:
                        new doMySQL().execute();
                        break;
                }
            }
        }
    });
}

public class doMySQL extends AsyncTask<Void, Void, String> {

    final String uname = username.getText().toString();
    final String passwd = password.getText().toString();
    String getUsername = null;
    String getPassword = null;
    String getPermission = null;
    String resValue = "undone";
    int exists = 0;

    protected void onPreExecute() {
        progressBar.setVisibility(View.VISIBLE);
    }

    protected String doInBackground(Void... params) {
        StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
        StrictMode.setThreadPolicy(policy);
        conn = DBConnect.Connector();

        try {
            pst = conn.prepareStatement("SELECT username FROM userList WHERE username=?");
            pst.setString(1, String.valueOf(uname));
            rs = pst.executeQuery();
            if (rs.next()) {
                getUsername = rs.getString(1);
            }
            pst = conn.prepareStatement("SELECT username FROM userList WHERE username=?");
            pst.setString(1, String.valueOf(uname));
            rs = pst.executeQuery();
            if (rs.wasNull()) {
                Toast.makeText(MainActivity.this, "Hibás felhasználónév / jelszó!", Toast.LENGTH_SHORT).show();
                resValue = "undone";
            }

            pst = conn.prepareStatement("SELECT password FROM userList WHERE username=?");
            pst.setString(1, String.valueOf(uname));
            rs = pst.executeQuery();
            if (rs.next()) {
                getPassword = rs.getString(1);
            }
            pst = conn.prepareStatement("SELECT password FROM userList WHERE username=?");
            pst.setString(1, String.valueOf(uname));
            rs = pst.executeQuery();
            if (rs.wasNull()) {
                Toast.makeText(MainActivity.this, "Hibás felhasználónév / jelszó!", Toast.LENGTH_SHORT).show();
                resValue = "undone";
            }

            pst = conn.prepareStatement("SELECT username FROM userList WHERE username=? AND password=?");
            pst.setString(1, String.valueOf(uname));
            pst.setString(2, String.valueOf(passwd));
            rs = pst.executeQuery();
            if (rs.next()) {
                exists = 1;
            }
            pst = conn.prepareStatement("SELECT username FROM userList WHERE username=? AND password=?");
            pst.setString(1, String.valueOf(uname));
            pst.setString(2, String.valueOf(passwd));
            if (rs.wasNull()) {
                Toast.makeText(MainActivity.this, "Hibás felhasználónév / jelszó!", Toast.LENGTH_SHORT).show();
                exists = 0;
                resValue = "undone";
            }

            if (exists == 1) {
                pst = conn.prepareStatement("SELECT permission FROM userList WHERE username=?");
                pst.setString(1, String.valueOf(uname));
                rs = pst.executeQuery();
                while (rs.next()) {
                    getPermission = rs.getString(1);
                    resValue = "Done";
                }
            }

        } catch (SQLException e) {
            Toast.makeText(MainActivity.this, "Hibás felhasználónév / jelszó!", Toast.LENGTH_SHORT).show();
        }

        return resValue;
    }

    protected void onPostExecute(String result) {
        if ("Done".equals(result)) {
            progressBar.setVisibility(View.GONE);
            if ("teacher".equals(getPermission)) {
                Intent openTeacher = new Intent(MainActivity.this, TeacherLogin.class);
                progressBar.setVisibility(View.GONE);
                startActivity(openTeacher);
            } else if ("student".equals(getPermission)) {
                Intent openStudent = new Intent(MainActivity.this, StudentLogin.class);
                progressBar.setVisibility(View.GONE);
                startActivity(openStudent);
            }
        } else if ("undone".equals(result)) {
            Toast.makeText(MainActivity.this, "Hibás felhasználónév / jelszó!", Toast.LENGTH_SHORT).show();
            progressBar.setVisibility(View.GONE);
        }
    }
}

}

当我通过USB上的“运行”命令安装该应用程序时，该应用程序可以运行，但是如果我要安装app-debug.apk，则该应用程序将无法运行。

我的lib文件夹中有一个mysql-connector-java依赖项，仅此而已。

Answer 1

有趣的事实:当我使用Windows资源管理器将app-debug.apk复制到SDCard时，应用程序在启动后会自行停止。但是，如果我打开一个新命令行并进行以下操作:

adb install app-debug.apk

在 输出/ apk / 文件夹中可以正常工作。我认为这就是解决方案。