java - Android Studio EditText 字段给出 null 或 0

Question

我正在尝试按照本教程系列创建登录和注册应用程序:https://www.youtube.com/watch?v=JQXfIidfFMo

我遇到的唯一问题是用户名字段被作为“0”放入数据库中，我浏览了所有内容，但无法弄清楚!所有其他字段都工作得很好!

activity_register.xml:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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:id="@+id/activity_register"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.mcrlogs.pp.mcrproximitypatrol.RegisterActivity">

    <EditText
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:ems="10"
        android:id="@+id/etName"
        android:hint="@string/real_name"
        android:inputType="textPersonName"
        android:layout_below="@+id/imageView"
        android:layout_alignParentStart="true"
        android:layout_alignParentEnd="true" />

    <EditText
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:ems="10"
        android:id="@+id/etEmail"
        android:hint="@string/email"
        android:inputType="textEmailAddress"
        android:layout_below="@+id/etName"
        android:layout_alignParentStart="true"
        android:layout_alignParentEnd="true" />

    <EditText
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:ems="10"
        android:id="@+id/etUser"
        android:hint="@string/user_name"
        android:layout_below="@+id/etEmail"
        android:layout_alignParentStart="true"
        android:layout_alignParentEnd="true" />

    <Button
        android:text="@string/register"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/bRegister"
        android:layout_below="@+id/etPassword"
        android:layout_alignParentStart="true"
        android:layout_alignParentEnd="true" />

    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="150dp"
        app:srcCompat="@mipmap/security"
        android:id="@+id/imageView"
        tools:contentDescription="MCR Security Logo"
        android:layout_alignParentTop="true"
        android:layout_alignParentStart="true"
        android:layout_alignParentEnd="true"
        android:contentDescription="@string/logo" />

    <EditText
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:ems="10"
        android:id="@+id/etPassword"
        android:hint="@string/password"
        android:inputType="textPassword"
        android:layout_below="@+id/etUser"
        android:layout_alignParentStart="true"
        android:layout_alignParentEnd="true" />


</RelativeLayout>

RegisterActivity.java:

package com.mcrlogs.pp.test;

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

import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.toolbox.Volley;

import org.json.JSONException;
import org.json.JSONObject;

public class RegisterActivity extends AppCompatActivity {

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

        final EditText etName = (EditText) findViewById(R.id.etName);
        final EditText etEmail = (EditText) findViewById(R.id.etEmail);
        final EditText etUser = (EditText) findViewById(R.id.etUser);
        final EditText etPassword = (EditText) findViewById(R.id.etPassword);
        final Button bRegister = (Button) findViewById(R.id.bRegister);

        bRegister.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                final String name = etName.getText().toString();
                final String email = etEmail.getText().toString();
                final String user = etUser.getText().toString();
                final String password = etPassword.getText().toString();

                Response.Listener<String> responseListener = new Response.Listener<String>(){

                    @Override
                    public void onResponse(String response) {
                        try {
                            JSONObject jsonResponse = new JSONObject(response);
                            boolean success = jsonResponse.getBoolean("success");
                            if(success) {
                                Intent intent = new Intent(RegisterActivity.this, LoginActivity.class);
                                RegisterActivity.this.startActivity(intent);
                            }else{
                                AlertDialog.Builder builder = new AlertDialog.Builder(RegisterActivity.this);
                                builder.setMessage("Registration Failed")
                                        .setNegativeButton("Retry", null)
                                        .create()
                                        .show();
                            }

                        } catch (JSONException e) {
                            e.printStackTrace();
                        }
                    }
                };

                RegisterRequest registerRequest = new RegisterRequest(name, email, user, password, responseListener);
                RequestQueue queue = Volley.newRequestQueue(RegisterActivity.this);
                queue.add(registerRequest);
            }
        });
    }
}

RegisterRequest.java:

package com.mcrlogs.pp.test;

import com.android.volley.Response;
import com.android.volley.toolbox.StringRequest;

import java.util.HashMap;
import java.util.Map;

/**
 * Created by sbuckley on 12/01/2017.
 */

public class RegisterRequest extends StringRequest {

    private static final String REGISTER_REQUEST_URL = "https://www.example.com/Register.php";
    private Map<String, String> params;
    public RegisterRequest(String name, String email, String user, String password, Response.Listener<String> listener){
        super(Method.POST, REGISTER_REQUEST_URL, listener, null);
        params = new HashMap<>();
        params.put("name", name);
        params.put("email", email);
        params.put("user", user);
        params.put("password", password);
    }

    @Override
    public Map<String, String> getParams() {
        return params;
    }
}

最后是服务器上的 Register.php 脚本(我认为这是无关紧要的，因为 null 来自 Android 应用程序端)。

<?php
    $con = mysqli_connect("localhost", "root", "password.", "database");
    /* check connection */
    if (!$con) {
    printf("Connect failed: %s\n", mysqli_connect_error());
    exit();
    }

    $name = $_POST["name"];
    $email = $_POST["email"];
    $user = $_POST["user"];
    $password = $_POST["password"];

    $statement = mysqli_prepare($con, "INSERT INTO users (name, user, email, password) VALUES (?, ?, ?, ?)");
    mysqli_stmt_bind_param($statement, "siss", $name, $user, $email, $password);
    mysqli_stmt_execute($statement);
    $response = array();
    $response["success"] = true;  

    echo json_encode($response);
?>

LogCat:

01-13 07:59:59.563 2598-2598/? I/art: Not late-enabling -Xcheck:jni (already on)
01-13 07:59:59.568 2598-2598/? W/art: Unexpected CPU variant for X86 using defaults: x86
01-13 07:59:59.606 2598-2598/com.mcrlogs.pp.test W/System: ClassLoader referenced unknown path: /data/app/com.mcrlogs.pp.test-1/lib/x86
01-13 07:59:59.614 2598-2598/com.mcrlogs.pp.test I/InstantRun: Instant Run Runtime started. Android package is com.mcrlogs.pp.test, real application class is null.

                                                                             [ 01-13 07:59:59.631  1541: 1568 D/         ]
                                                                             HostConnection::get() New Host Connection established 0x96f7f380, tid 1568
01-13 08:00:07.316 2598-2598/com.mcrlogs.pp.test W/System: ClassLoader referenced unknown path: /data/app/com.mcrlogs.pp.test-1/lib/x86
01-13 08:00:08.156 2598-2598/com.mcrlogs.pp.test W/art: Verification of int android.support.v4.app.FragmentActivity.allocateRequestIndex(android.support.v4.app.Fragment) took 330.188ms
01-13 08:00:08.863 2598-2598/com.mcrlogs.pp.test W/art: Before Android 4.1, method android.graphics.PorterDuffColorFilter android.support.graphics.drawable.VectorDrawableCompat.updateTintFilter(android.graphics.PorterDuffColorFilter, android.content.res.ColorStateList, android.graphics.PorterDuff$Mode) would have incorrectly overridden the package-private method in android.graphics.drawable.Drawable
01-13 08:00:09.315 2598-2712/com.mcrlogs.pp.test I/OpenGLRenderer: Initialized EGL, version 1.4
01-13 08:00:09.315 2598-2712/com.mcrlogs.pp.test D/OpenGLRenderer: Swap behavior 1
01-13 08:00:09.384 2598-2712/com.mcrlogs.pp.test E/EGL_emulation: tid 2712: eglSurfaceAttrib(1146): error 0x3009 (EGL_BAD_MATCH)
01-13 08:00:09.385 2598-2712/com.mcrlogs.pp.test W/OpenGLRenderer: Failed to set EGL_SWAP_BEHAVIOR on surface 0x9a3de140, error=EGL_BAD_MATCH
01-13 08:00:12.178 2598-2712/com.mcrlogs.pp.test E/EGL_emulation: tid 2712: eglSurfaceAttrib(1146): error 0x3009 (EGL_BAD_MATCH)
01-13 08:00:12.178 2598-2712/com.mcrlogs.pp.test W/OpenGLRenderer: Failed to set EGL_SWAP_BEHAVIOR on surface 0xa94f6900, error=EGL_BAD_MATCH
01-13 08:00:12.639 2598-2598/com.mcrlogs.pp.test W/IInputConnectionWrapper: finishComposingText on inactive InputConnection
01-13 08:00:17.240 2598-2598/com.mcrlogs.pp.test W/IInputConnectionWrapper: finishComposingText on inactive InputConnection
01-13 08:00:17.240 2598-2598/com.mcrlogs.pp.test W/IInputConnectionWrapper: finishComposingText on inactive InputConnection
01-13 08:00:25.652 2598-2712/com.mcrlogs.pp.test E/EGL_emulation: tid 2712: eglSurfaceAttrib(1146): error 0x3009 (EGL_BAD_MATCH)
01-13 08:00:25.652 2598-2712/com.mcrlogs.pp.test W/OpenGLRenderer: Failed to set EGL_SWAP_BEHAVIOR on surface 0x99497ce0, error=EGL_BAD_MATCH
01-13 08:00:26.882 2598-2712/com.mcrlogs.pp.test E/EGL_emulation: tid 2712: eglSurfaceAttrib(1146): error 0x3009 (EGL_BAD_MATCH)
01-13 08:00:26.882 2598-2712/com.mcrlogs.pp.test W/OpenGLRenderer: Failed to set EGL_SWAP_BEHAVIOR on surface 0x99497ea0, error=EGL_BAD_MATCH
01-13 08:00:27.709 2598-2598/com.mcrlogs.pp.test W/IInputConnectionWrapper: finishComposingText on inactive InputConnection
01-13 08:00:31.524 2598-2598/com.mcrlogs.pp.test W/IInputConnectionWrapper: finishComposingText on inactive InputConnection
01-13 08:00:31.524 2598-2598/com.mcrlogs.pp.test W/IInputConnectionWrapper: finishComposingText on inactive InputConnection
01-13 08:00:31.568 2598-2712/com.mcrlogs.pp.test E/EGL_emulation: tid 2712: eglSurfaceAttrib(1146): error 0x3009 (EGL_BAD_MATCH)
01-13 08:00:31.568 2598-2712/com.mcrlogs.pp.test W/OpenGLRenderer: Failed to set EGL_SWAP_BEHAVIOR on surface 0x99a463e0, error=EGL_BAD_MATCH
01-13 08:00:31.684 2598-2712/com.mcrlogs.pp.test E/EGL_emulation: tid 2712: eglSurfaceAttrib(1146): error 0x3009 (EGL_BAD_MATCH)
01-13 08:00:31.685 2598-2712/com.mcrlogs.pp.test W/OpenGLRenderer: Failed to set EGL_SWAP_BEHAVIOR on surface 0x99497ea0, error=EGL_BAD_MATCH
01-13 08:00:38.850 2598-2712/com.mcrlogs.pp.test  E/EGL_emulation: tid 2712: eglSurfaceAttrib(1146): error 0x3009 (EGL_BAD_MATCH)
01-13 08:00:38.850 2598-2712/com.mcrlogs.pp.test W/OpenGLRenderer: Failed to set EGL_SWAP_BEHAVIOR on surface 0x99497ea0, error=EGL_BAD_MATCH
01-13 08:00:42.997 2598-2598/com.mcrlogs.pp.test W/IInputConnectionWrapper: finishComposingText on inactive InputConnection
01-13 08:00:48.922 2598-2888/com.mcrlogs.pp.test D/NetworkSecurityConfig: No Network Security Config specified, using platform default
01-13 08:00:49.791 2598-2712/com.mcrlogs.pp.test E/EGL_emulation: tid 2712: eglSurfaceAttrib(1146): error 0x3009 (EGL_BAD_MATCH)
01-13 08:00:49.791 2598-2712/com.mcrlogs.pp.test W/OpenGLRenderer: Failed to set EGL_SWAP_BEHAVIOR on surface 0x994b8ca0, error=EGL_BAD_MATCH
01-13 08:00:49.862 2598-2598/com.mcrlogs.pp.test W/IInputConnectionWrapper: finishComposingText on inactive InputConnection

Answer 1

您的用户名值必须采用String，并且您将int传递给它，所以

更改此:

mysqli_stmt_bind_param($statement, "siss", $name, $user, $email, $password);
                                     ^//error

在您的 PHP 代码中使用此代码:

mysqli_stmt_bind_param($statement, "ssss", $name, $user, $email, $password);