当我按下登录按钮Java且应用程序崩溃时，我不断收到错误消息

时间：2019-03-09 18:56:24

标签： java android login server

当我按下登录按钮时，此错误导致我的应用程序崩溃。发生的错误如下。我尝试了很多事情，例如将send函数放在另一个脚本中。我还尝试了在另一个想法（例如eclipse）中单独运行send函数，并且没有错误。我是Java的新手，已经花费了数小时试图解决此问题。错误是

E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.messager, PID: 19051
    java.lang.IllegalStateException: Could not execute method for android:onClick
        at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:390)
        at android.view.View.performClick(View.java:6614)
        at android.view.View.performClickInternal(View.java:6591)
        at android.view.View.access$3100(View.java:786)
        at android.view.View$PerformClick.run(View.java:25948)
        at android.os.Handler.handleCallback(Handler.java:873)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:201)
        at android.app.ActivityThread.main(ActivityThread.java:6806)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873)
     Caused by: java.lang.reflect.InvocationTargetException
        at java.lang.reflect.Method.invoke(Native Method)
        at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:385)
        at android.view.View.performClick(View.java:6614) 
        at android.view.View.performClickInternal(View.java:6591) 
        at android.view.View.access$3100(View.java:786) 
        at android.view.View$PerformClick.run(View.java:25948) 
        at android.os.Handler.handleCallback(Handler.java:873) 
        at android.os.Handler.dispatchMessage(Handler.java:99) 
        at android.os.Looper.loop(Looper.java:201) 
        at android.app.ActivityThread.main(ActivityThread.java:6806) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873) 
     Caused by: android.os.NetworkOnMainThreadException
        at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1513)
        at java.net.Inet6AddressImpl.lookupHostByName(Inet6AddressImpl.java:117)
        at java.net.Inet6AddressImpl.lookupAllHostAddr(Inet6AddressImpl.java:105)
        at java.net.InetAddress.getAllByName(InetAddress.java:1154)
        at java.net.Socket.<init>(Socket.java:218)
        at com.example.messager.SendCredentials.Send(SendCredentials.java:35)
        at com.example.messager.MainActivity.LoginClick(MainActivity.java:30)
        at java.lang.reflect.Method.invoke(Native Method) 
        at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:385) 
        at android.view.View.performClick(View.java:6614) 
        at android.view.View.performClickInternal(View.java:6591) 
        at android.view.View.access$3100(View.java:786) 
        at android.view.View$PerformClick.run(View.java:25948) 
        at android.os.Handler.handleCallback(Handler.java:873) 
        at android.os.Handler.dispatchMessage(Handler.java:99) 
        at android.os.Looper.loop(Looper.java:201) 
        at android.app.ActivityThread.main(ActivityThread.java:6806) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873) 

我有两个脚本，它们是

package com.example.messager;

import android.support.design.widget.TextInputLayout;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import java.net.*;
import java.io.*;

public class MainActivity extends AppCompatActivity {
    public String Username;
    public String Password;
    public EditText passwordText;
    public EditText emailText;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);



    }
    public void LoginClick(View view){
        EditText passwordText = (EditText) findViewById(R.id.Password);
        EditText emailText = (EditText) findViewById(R.id.Email);
        String Username = emailText.getText().toString();
        String Password = passwordText.getText().toString();
        System.out.println(Username + " " + Password);
        SendCredentials.Send(Password, Username);
        }

}

和

package com.example.messager;

import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.EditText;

import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.Socket;
import java.net.UnknownHostException;

public class SendCredentials{
        public static void Send(String Password, String Username){
        System.out.print("Test");
        String hostname = "localhost";
        int port = 4321;

        // declaration section:
        // clientSocket: our client socket
        // os: output stream
        // is: input stream

        Socket clientSocket = null;
        DataOutputStream os = null;
        BufferedReader is = null;

        // Initialization section:
        // Try to open a socket on the given port
        // Try to open input and output streams

        try {
            clientSocket = new Socket(hostname, port);
            os = new DataOutputStream(clientSocket.getOutputStream());
            is = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
        } catch (UnknownHostException e) {
            System.err.println("Don't know about host: " + hostname);
        } catch (IOException e) {
            System.err.println("Couldn't get I/O for the connection to: " + hostname);
        }

        // If everything has been initialized then we want to write some data
        // to the socket we have opened a connection to on the given port

        if (clientSocket == null || os == null || is == null) {
            System.err.println( "Something is wrong. One variable is null." );
            return;
        }

        try {
            os.writeUTF(Username + Password);
            os.close();
            is.close();
            clientSocket.close();
        } catch (UnknownHostException e) {
            System.err.println("Trying to connect to unknown host: " + e);
        } catch (IOException e) {
            System.err.println("IOException:  " + e);
        }
    }
}

XML文件是

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <TextView
        android:id="@+id/Welcome"
        android:layout_width="198dp"
        android:layout_height="52dp"
        android:layout_marginStart="104dp"
        android:layout_marginTop="68dp"
        android:text="Welcome"
        android:textAlignment="center"
        android:textAllCaps="false"
        android:textColor="@color/colorPrimaryDark"
        android:textSize="36sp"
        android:textStyle="bold"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <android.support.design.widget.TextInputLayout
        android:id="@+id/passwordWrapper"
        android:layout_width="387dp"
        android:layout_height="56dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="444dp"
        android:hint="Password"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent">

        <android.support.design.widget.TextInputEditText
            android:id="@+id/Password"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:hint="Password"
            android:inputType="textPassword"
            android:textSize="18sp" />
    </android.support.design.widget.TextInputLayout>

    <android.support.design.widget.TextInputLayout
        android:id="@+id/emailWrapper"
        android:layout_width="397dp"
        android:layout_height="56dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="368dp"
        android:hint="Email"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent">

        <android.support.design.widget.TextInputEditText
            android:id="@+id/Email"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:hint="Email"
            android:inputType="textWebEmailAddress"
            android:textAlignment="textStart"
            android:textSize="18sp" />

    </android.support.design.widget.TextInputLayout>

    <Button
        android:id="@+id/LoginButton"
        android:layout_width="348dp"
        android:layout_height="45dp"
        android:layout_marginStart="28dp"
        android:layout_marginTop="520dp"
        android:onClick="LoginClick"
        android:text="LOGIN"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</android.support.constraint.ConstraintLayout>

1 个答案:

答案 0 :(得分：0)

在android中，您无法在主线程上运行网络操作，而在另一个线程中运行这些任务，例如：

Thread mThread = new Thread(new Runnable() {

@Override
public void run() {
try  {
    //Put your code here
} catch (Exception e) {
    e.printStackTrace();
 }
}
});

mThread.start
相关问题
最新问题