试图解决强制转换错误

Question

我目前正在尝试创建注册页面的项目。下面是我的两个活动的代码：

我的开始活动代码如下：

package com.example.profmox.k_mart;

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

public class Start extends AppCompatActivity {
    private Button regButton;

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

        regButton = (Button)findViewById(R.id.register);
        regButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent reg_intent = new Intent(Start.this,Register.class);
                startActivity(reg_intent);
            }
        });
    }
}

和我的Register类代码：

package com.example.profmox.k_mart;

import android.content.Intent;
import android.support.annotation.NonNull;
import android.support.design.widget.TextInputLayout;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.AuthResult;
import com.google.firebase.auth.FirebaseAuth;

public class Register extends AppCompatActivity {
    private TextInputLayout regName,regEmail,regPassword;
    private Button regCreate;
    private FirebaseAuth mAuth;

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

        mAuth = FirebaseAuth.getInstance();

        regName = (TextInputLayout)findViewById(R.id.reg_displayName);
        regEmail = (TextInputLayout)findViewById(R.id.reg_email);
        regPassword = (TextInputLayout)findViewById(R.id.reg_password);
        regCreate = (Button)findViewById(R.id.reg_create);

        regCreate.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String display_name = regName.getEditText().getText().toString();
                String email = regEmail.getEditText().getText().toString();
                String password = regPassword.getEditText().getText().toString();

                registerUser(display_name,email,password);
            }
        });
    }

    private void registerUser(String display_name, String email, String password) {
        mAuth.createUserWithEmailAndPassword(email, password)
                .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
                    @Override
                    public void onComplete(@NonNull Task<AuthResult> task) {
                        if (task.isSuccessful()) {
                            // Sign in success, update UI with the signed-in user's information
                            startActivity(new Intent(Register.this, MainActivity.class));
                            finish();
                        } else {
                            // If sign in fails, display a message to the user.
                            Toast.makeText(Register.this, "Authentication failed.",
                                    Toast.LENGTH_SHORT).show();
                        }
                    }
                });
    }
}

我的开始活动的布局代码：

<?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:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".Start">

    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:text="Welcome to K-Mart"
        android:textSize="24dp"/>

    <Button
        android:id="@+id/register"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:layout_marginBottom="126dp"
        android:text="@string/need_a_new_account" />
</RelativeLayout>

我的注册活动的布局代码：

<?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=".Register">

    <android.support.design.widget.TextInputLayout
        android:id="@+id/textInputLayout"
        android:layout_width="368dp"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="90dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent">

        <android.support.design.widget.TextInputEditText
            android:id="@+id/reg_displayName"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="@string/display_name" />
    </android.support.design.widget.TextInputLayout>

    <android.support.design.widget.TextInputLayout
        android:id="@+id/reg_email"
        android:layout_width="368dp"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textInputLayout">

        <android.support.design.widget.TextInputEditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="@string/email" />
    </android.support.design.widget.TextInputLayout>

    <android.support.design.widget.TextInputLayout
        android:id="@+id/reg_password"
        android:layout_width="368dp"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/reg_email">

        <android.support.design.widget.TextInputEditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="@string/password" />
    </android.support.design.widget.TextInputLayout>

    <Button
        android:id="@+id/reg_create"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:layout_marginTop="8dp"
        android:text="@string/create_account"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/reg_password" />
</android.support.constraint.ConstraintLayout>

但是每次我在启动活动中单击按钮时，它都会使应用程序崩溃并发出以下错误消息：

 08-21 15:55:34.884 9689-9689/com.example.profmox.k_mart E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.profmox.k_mart, PID: 9689
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.profmox.k_mart/com.example.profmox.k_mart.Register}: java.lang.ClassCastException: android.support.design.widget.TextInputLayout cannot be cast to android.widget.EditText
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2778)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856)
        at android.app.ActivityThread.-wrap11(Unknown Source:0)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loop(Looper.java:164)
        at android.app.ActivityThread.main(ActivityThread.java:6494)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
     Caused by: java.lang.ClassCastException: android.support.design.widget.TextInputLayout cannot be cast to android.widget.EditText
        at com.example.profmox.k_mart.Register.onCreate(Register.java:31)
        at android.app.Activity.performCreate(Activity.java:7009)
        at android.app.Activity.performCreate(Activity.java:7000)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1214)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2731)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2856) 
        at android.app.ActivityThread.-wrap11(Unknown Source:0) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1589) 
        at android.os.Handler.dispatchMessage(Handler.java:106) 
        at android.os.Looper.loop(Looper.java:164) 
        at android.app.ActivityThread.main(ActivityThread.java:6494) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807) 

我如何解决此问题，因为我无法在代码中的任何地方显示错误。

Answer 1

密码android.support.design.widget.TextInputLayout instead of android.support.design.widget.EditTextLayout

同时投射视图

Answer 2

更改注册活动的布局：

<?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">

    <android.support.design.widget.TextInputLayout
        android:id="@+id/textInputLayout1"
        android:layout_width="368dp"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="90dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent">

        <android.support.design.widget.TextInputEditText
            android:id="@+id/reg_displayName"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="string/display_name" />
    </android.support.design.widget.TextInputLayout>

    <android.support.design.widget.TextInputLayout
        android:id="@+id/textInputLayout2"
        android:layout_width="368dp"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textInputLayout1">

        <android.support.design.widget.TextInputEditText
            android:id="@+id/reg_email"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="string/email" />
    </android.support.design.widget.TextInputLayout>

    <android.support.design.widget.TextInputLayout
        android:id="@+id/textInputLayout3"
        android:layout_width="368dp"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="8dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textInputLayout2">

        <android.support.design.widget.TextInputEditText
            android:id="@+id/reg_password"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:hint="string/password" />
    </android.support.design.widget.TextInputLayout>

    <Button
        android:id="@+id/reg_create"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginEnd="8dp"
        android:layout_marginTop="8dp"
        android:text="string/create_account"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toBottomOf="@+id/textInputLayout3" />
</android.support.constraint.ConstraintLayout>

更改：

private TextInputEditText regName,regEmail,regPassword;

regName = (TextInputEditText)findViewById(R.id.reg_displayName);
regEmail = (TextInputEditText)findViewById(R.id.reg_email);
regPassword = (TextInputEditText)findViewById(R.id.reg_password);

和

    public void onClick(View view) {
        String display_name = regName.getText().toString();
        String email = regEmail.getText().toString();
        String password = regPassword.getText().toString();

        registerUser(display_name,email,password);
    }

Answer 3

将您的TextInputLayout更改为TextInputEditText

    private TextInputEditText regName,regEmail,regPassword;

    regName = (TextInputEditText)findViewById(R.id.reg_displayName);
    regEmail = (TextInputEditText)findViewById(R.id.reg_email);
    regPassword = (TextInputEditText)findViewById(R.id.reg_password);

还

regCreate.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String display_name = regName.getText().toString();
                String email = regEmail.getText().toString();
                String password = regPassword.getText().toString();
                registerUser(display_name,email,password);
            }
        });