无法在主要活动上显示操作栏

Question

style.xml

here i purposely disable action bar because i dont want it to appear on my splash screen

 <style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">
            <!-- Customize your theme here. -->
            <item name="colorPrimary">@color/colorPrimary</item>
            <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
            <item name="colorAccent">@color/colorAccent</item>
        </style>

MainActivity.java

After that I want action bar exist in Main activity by using set supportactionbar, but the action bar doesnt work after I run the code, and whole process is without error, can someone tell me what's wrong with my code.

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

Answer 1

You have two options.

1: Manually add a Toolbar in your XML. Example:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    android:orientation="vertical">

    <android.support.v7.widget.Toolbar
      android:id="@+id/toolbar"
      android:minHeight="?attr/actionBarSize"  
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      app:titleTextColor="@android:color/white"
      android:background="?attr/colorPrimary">
    </android.support.v7.widget.Toolbar>

</LinearLayout>

See https://guides.codepath.com/android/Using-the-App-Toolbar for more toolbar information.

OR

2: Create a new theme for your splash screen and set it in your manifest. Example:

    <activity
        android:name=".view.activity.SplashActivity"
        android:theme="@style/Splash">
        <intent-filter>
            <action android:name="android.intent.action.MAIN"/>
            <category android:name="android.intent.category.LAUNCHER"/>
        </intent-filter>
    </activity>

And then in your app's styles.xml:

<style name="Splash" parent="Theme.AppCompat.NoActionBar">
    <item name="android:windowFullscreen">true</item>
    <item name="colorPrimary">@color/colorPrimary</item>
    <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
    <item name="android:windowBackground">@drawable/splash_screen</item>
</style>

<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
    <item name="colorPrimary">@color/colorPrimary</item>
    <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
    <item name="colorAccent">@color/colorAccent</item>
</style>

Either one of these are fine, although personally I always keep a separate style for my splash screen just to keep things clean and simple.