java - 添加工具栏后android应用程序崩溃

问题描述

所以我有一个android应用程序，如果我尝试打开它就会崩溃。这在我添加工具栏后开始发生。

这是我的 MainActivity.java

import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.widget.PopupMenu;
import android.widget.Toast;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import androidx.appcompat.widget.Toolbar;


public class MainActivity extends AppCompatActivity {
    Toolbar toolbar;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        toolbar = (Toolbar) findViewById(R.id.toolbar2);
        setSupportActionBar(toolbar);
        toolbar.setTitle("Title");

    }
   
    
    @Override
    public boolean onCreateOptionsMenu(Menu menu){
        getMenuInflater().inflate(R.menu.navigation_menu, menu);
        return true;
    }
    @Override
    public boolean onOptionsItemSelected(MenuItem item){
        switch(item.getItemId()){
            case R.id.action_add_contact:
                Toast.makeText(MainActivity.this,"Add Contacts",Toast.LENGTH_LONG).show();

                return true;
            case R.id.action_about_us:
                Toast.makeText(MainActivity.this,"About Us",Toast.LENGTH_LONG).show();

                return true;
            case R.id.action_settings:
                Toast.makeText(MainActivity.this,"Settings",Toast.LENGTH_LONG).show();

                return true;
            default:
                return super.onOptionsItemSelected(item);
        }
    }
}

主要活动 xml:activity_main.xml

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

    <androidx.appcompat.widget.Toolbar
            android:layout_width="409dp"
            android:layout_height="53dp"
            android:background="#104885"
            android:theme="?attr/actionBarTheme"
            android:minHeight="?attr/actionBarSize"   
            android:id="@+id/toolbar2"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toStartOf="parent"
            android:layout_marginStart="2dp"
            app:layout_constraintTop_toTopOf="parent"
            android:visibility="visible"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
            android:fadeScrollbars="true"
            app:menu="@menu/navigation_menu"
            app:subtitleTextColor="@color/design_default_color_background"
            app:title="test2"/>

我正在使用的菜单 xml：navigation_menu.xml

<?xml version="1.0" encoding="utf-8"?>
<menu 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">
    <item
            android:id="@+id/action_more"
            android:icon="@drawable/ic_baseline_more_vert_24"
            android:title="Settings"
            app:showAsAction="always"
            tools:showIn="@layout/activity_main" android:enabled="true" android:checkable="false"
            android:menuCategory="container" android:onClick="onCreateOptionsMenu">
        <menu>
            <item
                    android:id="@+id/action_add_contact"
                    android:icon="@drawable/ic_person_add_black_24dp"
                    android:title="Add contact"
                    app:showAsAction="ifRoom" tools:showIn="@layout/activity_main"
                    android:onClick="onOptionsItemSelected"/>
            <item
                    android:id="@+id/action_settings"
                    android:icon="@drawable/ic_settings_black_24dp"
                    android:title="Settings"
                    app:showAsAction="ifRoom"
                    tools:showIn="@layout/activity_main" android:onClick="onOptionsItemSelected"/>
            <item
                    android:id="@+id/action_about_us"
                    android:icon="@drawable/ic_info_outline_black_24dp"
                    android:title="About us"
                    app:showAsAction="ifRoom"
                    tools:showIn="@layout/activity_main" android:onClick="onOptionsItemSelected"/>
        </menu>
    </item>
</menu>

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="com.testapp.test2">

    <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>

我究竟做错了什么？我尝试删除和添加工具栏，但没有成功。另外，我尝试了App 中工具栏崩溃的解决方案。

标签： javaandroid

java - 添加工具栏后android应用程序崩溃

问题描述

解决方案

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