无法启动 activity Android Studio

Question

我正在尝试通过单击 android 工作室中的按钮从一个 activity 切换到另一个。但是当我尝试时，我看到了第二个 activity，但没有默认的，只有第二个 activity，当我删除第二个 activity 时，我再也看不到第一个和我的应用程序关闭。

我的主要Activity

package com.niccode.desarrollounaapp;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

import androidx.appcompat.app.AppCompatActivity;

import com.google.android.material.datepicker.MaterialDatePicker;
import com.google.android.material.datepicker.MaterialPickerOnPositiveButtonClickListener;


public class MainActivity extends AppCompatActivity {


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

        Button Siguiente = (Button) findViewById(R.id.Siguiente);

        final EditText eName = findViewById(R.id.tiNombreCompleto);
        final EditText eFecha = findViewById(R.id.Calendario);
        final EditText eTelefono = findViewById(R.id.tiTelefono);
        final EditText eEmail = findViewById(R.id.tiEmail);
        final EditText eDescripcion = findViewById(R.id.tiDescripcionContacto);


        MaterialDatePicker.Builder<Long> builder = MaterialDatePicker.Builder.datePicker();
        builder.setTitleText(getResources().getString(R.string.date1));

        final MaterialDatePicker<Long> materialDatePicker = builder.build();

        eFecha.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                materialDatePicker.show(getSupportFragmentManager(), "DATE_PICKER");

            }
        });

        materialDatePicker.addOnPositiveButtonClickListener(new MaterialPickerOnPositiveButtonClickListener() {
            @Override
            public void onPositiveButtonClick(Object selection) {
                eFecha.setText(materialDatePicker.getHeaderText());
            }
        });
          /*

        Siguiente.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                Intent intent = new Intent(MainActivity.this, Confirmar_Datos.class);

                intent.putExtra(getResources().getString(R.string.pname), eName.getText().toString());
                intent.putExtra(getResources().getString(R.string.pdate),  eFecha.getText().toString());
                intent.putExtra(getResources().getString(R.string.ptelefono), eTelefono.getText().toString());
                intent.putExtra(getResources().getString(R.string.pemail),  eEmail.getText().toString());
                intent.putExtra(getResources().getString(R.string.pDescripcion),  eDescripcion.getText().toString());

                startActivity(intent);


            }
        });
  */
    }
}

我的 AndroidManifiest

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.niccode.desarrollounaapp">
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

XML 文件，在做之前我试过的方法是否有效

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    tools:context=".MainActivity"
    android:layout_height="match_parent"
    android:layout_width="match_parent"
    android:orientation="vertical"
    android:layout_marginTop="16dp"
    android:layout_marginRight="16dp"
    android:layout_marginLeft="16dp"
    >


    <com.google.android.material.textfield.TextInputLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
        android:layout_marginBottom = "10dp"
        >

        <com.google.android.material.textfield.TextInputEditText
            android:id="@+id/tiNombreCompleto"
            style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:drawableStart="@drawable/name"
            android:hint="@string/nombre_completo" />
    </com.google.android.material.textfield.TextInputLayout>

    <com.google.android.material.textfield.TextInputLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
        android:layout_marginBottom = "10dp"
        >

        <com.google.android.material.textfield.TextInputEditText
            android:id="@+id/Calendario"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:drawableStart="@drawable/date"
            android:focusable="false"
            android:hint="@string/date1"
           >
        </com.google.android.material.textfield.TextInputEditText>

    </com.google.android.material.textfield.TextInputLayout>

    <com.google.android.material.textfield.TextInputLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
        android:layout_marginBottom = "10dp"
        >

        <com.google.android.material.textfield.TextInputEditText
            android:id="@+id/tiTelefono"
            android:hint="@string/telefono"
            android:drawableStart="@drawable/telefono"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            />
    </com.google.android.material.textfield.TextInputLayout>


    <com.google.android.material.textfield.TextInputLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
        android:layout_marginBottom = "10dp"
        >

        <com.google.android.material.textfield.TextInputEditText
            android:id="@+id/tiEmail"
            android:hint="@string/email"
            android:drawableStart="@drawable/email"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            />
    </com.google.android.material.textfield.TextInputLayout>

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/descripcion_contacto"
        android:textSize="18sp"
        />

    <com.google.android.material.textfield.TextInputLayout
        android:id="@+id/tiDescripcionContacto"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
        android:layout_marginBottom = "10dp"
        >

        <com.google.android.material.textfield.TextInputEditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            />
    </com.google.android.material.textfield.TextInputLayout>

    <Button
        android:id="@+id/Siguiente"
        android:layout_width="match_parent"
        android:layout_height="60dp"
        android:text="@string/siguiente"
        android:theme="@style/MiRaisebtn" />

</LinearLayout>

Logcat

06-27 10:22:51.000 7158-7158/com.niccode.desarrollounaapp D/dalvikvm: VFY: replacing opcode 0x6f at 0x0004
06-27 10:22:51.010 7158-7158/com.niccode.desarrollounaapp D/AndroidRuntime: Shutting down VM
06-27 10:22:51.010 7158-7158/com.niccode.desarrollounaapp W/dalvikvm: threadid=1: thread exiting with uncaught exception (group=0x40afa930)
06-27 10:22:51.010 7158-7158/com.niccode.desarrollounaapp E/AndroidRuntime: FATAL EXCEPTION: main
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.niccode.desarrollounaapp/com.niccode.desarrollounaapp.MainActivity}: java.lang.ClassCastException: com.google.android.material.textfield.TextInputLayout cannot be cast to android.widget.EditText
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
        at android.app.ActivityThread.access0(ActivityThread.java:141)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at android.os.Looper.loop(Looper.java:137)
        at android.app.ActivityThread.main(ActivityThread.java:5041)
        at java.lang.reflect.Method.invokeNative(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:511)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
        at dalvik.system.NativeStart.main(Native Method)
     Caused by: java.lang.ClassCastException: com.google.android.material.textfield.TextInputLayout cannot be cast to android.widget.EditText
        at com.niccode.desarrollounaapp.MainActivity.onCreate(MainActivity.java:29)
        at android.app.Activity.performCreate(Activity.java:5131)
        at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1090)
        at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
        at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230) 
        at android.app.ActivityThread.access0(ActivityThread.java:141) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234) 
        at android.os.Handler.dispatchMessage(Handler.java:99) 
        at android.os.Looper.loop(Looper.java:137) 
        at android.app.ActivityThread.main(ActivityThread.java:5041) 
        at java.lang.reflect.Method.invokeNative(Native Method) 
        at java.lang.reflect.Method.invoke(Method.java:511) 
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560) 
        at dalvik.system.NativeStart.main(Native Method) 
06-27 10:22:53.420 7158-7158/com.niccode.desarrollounaapp I/Process: Sending signal. PID: 7158 SIG: 9

Answer 1

您已将 ID tiDescripcionContacto 指定为 TextInputLayout，然后将其转换为 EditText，只需更改以下代码：

<com.google.android.material.textfield.TextInputLayout
        android:id="@+id/tiDescripcionContacto"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
        android:layout_marginBottom = "10dp"
        >

        <com.google.android.material.textfield.TextInputEditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            />
    </com.google.android.material.textfield.TextInputLayout>

至：

<com.google.android.material.textfield.TextInputLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
        android:layout_marginBottom = "10dp">

        <com.google.android.material.textfield.TextInputEditText
            android:id="@+id/tiDescripcionContacto"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"/>

    </com.google.android.material.textfield.TextInputLayout>

Answer 2

像这样更改您的布局：

    <LinearLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:tools="http://schemas.android.com/tools"
        tools:context=".MainActivity"
        android:layout_height="match_parent"
        android:layout_width="match_parent"
        android:orientation="vertical"
        android:layout_marginTop="16dp"
        android:layout_marginRight="16dp"
        android:layout_marginLeft="16dp"
        >


        <com.google.android.material.textfield.TextInputLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
            android:layout_marginBottom = "10dp"
            >

            <EditText
                android:id="@+id/tiNombreCompleto"
                style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                />
        </com.google.android.material.textfield.TextInputLayout>

        <com.google.android.material.textfield.TextInputLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
            android:layout_marginBottom = "10dp"
            >

            <EditText
                android:id="@+id/Calendario"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                 android:focusable="false"
                 >
            </EditText>

        </com.google.android.material.textfield.TextInputLayout>

        <com.google.android.material.textfield.TextInputLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
            android:layout_marginBottom = "10dp"
            >

            <EditText
                android:id="@+id/tiTelefono"
                  android:layout_width="match_parent"
                android:layout_height="wrap_content"
                />
        </com.google.android.material.textfield.TextInputLayout>


        <com.google.android.material.textfield.TextInputLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
            android:layout_marginBottom = "10dp"
            >

            <EditText
                android:id="@+id/tiEmail"
                  android:layout_width="match_parent"
                android:layout_height="wrap_content"
                />
        </com.google.android.material.textfield.TextInputLayout>

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
             android:textSize="18sp"
            />

        <com.google.android.material.textfield.TextInputLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            style="@style/Widget.MaterialComponents.TextInputLayout.OutlinedBox"
            android:layout_marginBottom = "10dp"
            >

            <EditText
                android:id="@+id/tiDescripcionContacto"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                />
        </com.google.android.material.textfield.TextInputLayout>

        <Button
            android:id="@+id/Siguiente"
            android:layout_width="match_parent"
            android:layout_height="60dp"
             />

    </LinearLayout>

Answer 3

它在这一行崩溃：

final EditText eFecha = findViewById(R.id.Calendario);

你的 XML R.id.Calendario 是 TextInputLayout 而不是 EditText 所以它崩溃了

您可以将 TextInputLayout 替换为 EditText

Answer 4

final EditText eFecha = findViewById(R.id.Calendario);

根据 EditText 变量更改您的 XML 布局（位于 R.id.calendario）。它崩溃，因为你的 XML 布局与 EditText.

不匹配

Answer 5

问题是：

Caused by: java.lang.ClassCastException: com.google.android.material.textfield.TextInputLayout cannot be cast to android.widget.EditText

它发生在这里：

 final EditText eDescripcion = findViewById(R.id.tiDescripcionContacto);

这是你的布局：

   <com.google.android.material.textfield.TextInputLayout
        android:id="@+id/tiDescripcionContacto"
        ..>

        <com.google.android.material.textfield.TextInputEditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            />
    </com.google.android.material.textfield.TextInputLayout>

你应该使用:

TextInputLayout textinputlayout = findViewById(R.id.tiDescripcionContacto);
EditText eDescripcion = textinputlayout.getEditText();

无法启动 activity Android Studio

Unable to start activity Android Studio

android

android-intent