我正在开发一个Android应用程序,帮助: https://www.youtube.com/watch?v=T7Z4GVFaT4A&list=PLe60o7ed8E-TztoF2K3y4VdDgT6APZ0ka&index=4
当我回复相同的教程时,应用程序工作得很好。然后我调整了应用程序以适应我的应用程序想法。注册成功并按预期将数据存储到数据库中。 但是在LoginActivity中面临问题。
应用程序应该继续的预期方式:当我单击blogin按钮时,它应该验证存储在db中的用户并打开相应的AdminViewActivity。
实际发生的是当我点击按钮blogin时,没有任何反应。表名是“allusers”,已包含值。我通过我的应用程序登录时输入相同的值。
请帮我找出错误的地方。提前谢谢。
LoginActivity.java
package com.example.android.ablo;
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.Button;
import android.widget.EditText;
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 LoginActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
final Button bregister = (Button) findViewById(R.id.bregister);
final Button blogin = (Button) findViewById(R.id.blogin);
final EditText etusername=(EditText)findViewById(R.id.etusername);
final EditText etpassword=(EditText)findViewById(R.id.etpassword);
bregister.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent i = new Intent(LoginActivity.this, RegisterActivity.class);
LoginActivity.this.startActivity(i);
}
});
blogin.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View v){
final String username=etusername.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){
String name= jsonResponse.getString("name");
Intent i=new Intent(LoginActivity.this,AdminViewActivity.class);
i.putExtra("name",name);
LoginActivity.this.startActivity(i);
}else{
AlertDialog.Builder builder= new AlertDialog.Builder(LoginActivity.this);
builder.setMessage("Login Failed").setNegativeButton("Retry",null).create().show();
}
} catch (JSONException e) {
e.printStackTrace();
}
}
};
LoginRequest loginRequest=new LoginRequest(username,password,responseListener );
RequestQueue queue= Volley.newRequestQueue(LoginActivity.this);
queue.add(loginRequest);
}
});
}
}
LoginRequest.java
package com.example.android.ablo;
import com.android.volley.Request;
import com.android.volley.Response;
import com.android.volley.toolbox.StringRequest;
import java.util.HashMap;
import java.util.Map;
/**
* Created by User on 21-01-2018.
*/
public class LoginRequest extends StringRequest {
private static final String LOGIN_REQUEST_URL = "http://ablo.000webhostapp.com/AbloLogin.php";
private Map<String,String> params;
public LoginRequest( String username, String password, Response.Listener<String> listener){
super(Request.Method.POST, LOGIN_REQUEST_URL, listener, null );
params= new HashMap<>();
params.put("username",username);
params.put("password",password);
}
@Override
public Map<String, String> getParams() {
return params;
}
}
AbloLogin.php
<?php
$con = mysqli_connect("localhost", "id4335430_ablo_users", "wontreveal", "id4335430_ablo_users");
$username = $_POST["username"];
$password = $_POST["password"];
$statement = mysqli_prepare($con, "SELECT * FROM allusers WHERE username = ? AND password = ?");
mysqli_stmt_bind_param($statement, "ss", $username, $password);
mysqli_stmt_execute($statement);
mysqli_stmt_store_result($statement);
mysqli_stmt_bind_result($statement, $allusersID, $name, $username, $password);
$response = array();
$response["success"] = false;
while(mysqli_stmt_fetch($statement)){
$response["success"] = true;
$response["name"] = $name;
$response["username"] = $username;
$response["password"] = $password;
}
echo json_encode($response);
?>
AdminViewActivity.java
package com.example.android.ablo;
import android.content.Intent;
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.TextView;
import org.w3c.dom.Text;
public class AdminViewActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_admin_view);
final Button badduser = (Button) findViewById(R.id.badduser);
final Button bmanageusers = (Button) findViewById(R.id.bmanageusers);
final TextView tvadmin =(TextView) findViewById(R.id.tvadmin);
Intent i= getIntent();
String name= i.getStringExtra("name");
String message= name+ "'s Admin View";
tvadmin.setText(message);
badduser.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent i = new Intent(AdminViewActivity.this, CreateUserActivity.class);
AdminViewActivity.this.startActivity(i);
}
});
bmanageusers.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent i = new Intent(AdminViewActivity.this, ManageUsersActivity.class);
AdminViewActivity.this.startActivity(i);
}
});
}
}