android - 创建选项卡时我的工具栏出错

Question

我正在使用 androidhive 教程来设计我的选项卡，因为 tabhost 已被弃用。这是我第一次使用新功能。但是，我不断收到此错误:

java.lang.IllegalStateException: This Activity already has an action bar supplied by the window decor. Do not request Window.FEATURE_SUPPORT_ACTION_BAR and set windowActionBar to false in your theme to use a Toolbar instead.

我在这里阅读了类似问题的解决方案，建议的解决方案是在主题中设置一些属性，但是在我的 styles.xml 中一切看起来都不错

<resources>

<!-- Base application theme. -->
<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
    <!-- Customize your theme here. -->
    <item name="colorPrimary">@color/colorPrimary</item>
    <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
    <item name="colorAccent">@color/colorAccent</item>
</style>
<style name="AppTheme.NoActionBar">
    <item name="windowActionBar">false</item> <!--change here-->
    <item name="windowNoTitle">true</item>
</style>
<style name="AppTheme.AppBarOverlay" parent="ThemeOverlay.AppCompat.Dark.ActionBar" />
<style name="AppTheme.PopupOverlay" parent="ThemeOverlay.AppCompat.Light" />

<style name="button_text" >
    <item name="android:layout_width" >fill_parent</item>
    <item name="android:layout_height" >wrap_content</item>
    <item name="android:textColor" >#ffffff</item>
    <item name="android:gravity" >center</item>
    <item name="android:layout_margin" >3dp</item>
    <item name="android:textSize" >30sp</item>
    <item name="android:textStyle" >bold</item>
    <item name="android:shadowColor" >#000000</item>
    <item name="android:shadowDx" >1</item>
    <item name="android:shadowDy" >1</item>
    <item name="android:shadowRadius" >2</item>
</style>

</resources>

下面是我的 list 文件的一部分:

<activity
        android:name=".SplashActivity"
        android:label="@string/app_name"
        android:theme="@style/AppTheme.NoActionBar" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity
        android:name=".MainActivity"
        android:label="@string/title_activity_main"
        android:theme="@style/AppTheme.NoActionBar" >
    </activity>
    <activity android:name=".MaintenanceActivity" >
    </activity>
    <activity android:name=".ServicingActivity">
    </activity>

这里是activity_maintenance.xml

<android.support.design.widget.CoordinatorLayout
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="com.application.sweetiean.stlmaintenance.MaintenanceActivity">

<android.support.design.widget.AppBarLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:theme="@style/AppTheme.AppBarOverlay">

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        android:background="?attr/colorPrimary"
        app:layout_scrollFlags="scroll|enterAlways"
        app:popupTheme="@style/AppTheme.PopupOverlay" />

    <android.support.design.widget.TabLayout
        android:id="@+id/tabs"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:tabMode="fixed"
        app:tabGravity="fill"/>
</android.support.design.widget.AppBarLayout>

<android.support.v4.view.ViewPager
    android:id="@+id/viewpager"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_behavior="@string/appbar_scrolling_view_behavior"  />
</android.support.design.widget.CoordinatorLayout>

最后，这是 MaintenanceActivity.java

import android.support.design.widget.TabLayout;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;

import java.util.ArrayList;
import java.util.List;

public class MaintenanceActivity extends AppCompatActivity {

private Toolbar toolbar;
private TabLayout tabLayout;
private ViewPager viewPager;


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

    init();

}


public void init(){

    toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    getSupportActionBar().setDisplayHomeAsUpEnabled(true);

    viewPager = (ViewPager) findViewById(R.id.viewpager);
    setupViewPager(viewPager);

    tabLayout = (TabLayout) findViewById(R.id.tabs);
    tabLayout.setupWithViewPager(viewPager);

}

private void setupViewPager(ViewPager viewPager) {
    ViewPagerAdapter adapter = new ViewPagerAdapter(getSupportFragmentManager());
    adapter.addFragment(new OverviewFragment(), "Overview");
    adapter.addFragment(new BaseDataFragment(), "Base Data");
    adapter.addFragment(new TaskFragment(), "Task");
    adapter.addFragment(new ImageSignFragment(), "Images/Sign");
    viewPager.setAdapter(adapter);
}

class ViewPagerAdapter extends FragmentPagerAdapter {
    private final List<Fragment> mFragmentList = new ArrayList<>();
    private final List<String> mFragmentTitleList = new ArrayList<>();

    public ViewPagerAdapter(FragmentManager manager) {
        super(manager);
    }

    @Override
    public Fragment getItem(int position) {
        return mFragmentList.get(position);
    }

    @Override
    public int getCount() {
        return mFragmentList.size();
    }

    public void addFragment(Fragment fragment, String title) {
        mFragmentList.add(fragment);
        mFragmentTitleList.add(title);
    }

    @Override
    public CharSequence getPageTitle(int position) {
        return mFragmentTitleList.get(position);
    }
}

我看不出我的代码出了什么问题，因为我在启动主要 Activity 时没有收到相同的错误，所以我相信它与选项卡的实现有关。如果有人能帮助我，我将不胜感激。谢谢。

Answer 1

有关错误主题的错误:您正在尝试设置 Actionbar，而它已经存在。所以:

<activity android:name=".MaintenanceActivity" >
</activity>

您没有为此 Activity 设置主题。只需添加:

android:theme="@style/AppTheme.NoActionBar"

就像您对主要 Activity 所做的那样。 GL