Question

I have an ActionBar in an app, and it has navigation tabs embedded in it (not TabHost!). By default the tabs show as dark grey, with a thin blue line under all the tabs, and a blue marker on the selected tab.

Which styles do I override to change those colours?

Answer 1

I have not changed the tabs themselves, but I would assume that you can do it with these styles from styles.xml…

 <style name="Widget.Holo.TabWidget" parent="Widget.TabWidget">
        <item name="android:tabStripLeft">@null</item>
        <item name="android:tabStripRight">@null</item>
        <item name="android:tabStripEnabled">false</item>
        <item name="android:divider">?android:attr/dividerVertical</item>
        <item name="android:showDividers">middle</item>
        <item name="android:dividerPadding">8dip</item>
        <item name="android:measureWithLargestChild">true</item>
        <item name="android:tabLayout">@android:layout/tab_indicator_holo</item>
    </style>

with tab_indicator_holo.xml

  <selector xmlns:android="http://schemas.android.com/apk/res/android">
        <!-- Non focused states -->
        <item android:state_focused="false" android:state_selected="false" android:state_pressed="false" android:drawable="@drawable/tab_unselected_holo" />
        <item android:state_focused="false" android:state_selected="true"  android:state_pressed="false" android:drawable="@drawable/tab_selected_holo" />

        <!-- Focused states -->
        <item android:state_focused="true" android:state_selected="false" android:state_pressed="false" android:drawable="@drawable/tab_unselected_focused_holo" />
        <item android:state_focused="true" android:state_selected="true"  android:state_pressed="false" android:drawable="@drawable/tab_selected_focused_holo" />

        <!-- Pressed -->
        <!--    Non focused states -->
        <item android:state_focused="false" android:state_selected="false" android:state_pressed="true" android:drawable="@drawable/tab_unselected_pressed_holo" />
        <item android:state_focused="false" android:state_selected="true"  android:state_pressed="true" android:drawable="@drawable/tab_selected_pressed_holo" />

        <!--    Focused states -->
        <item android:state_focused="true" android:state_selected="false" android:state_pressed="true" android:drawable="@drawable/tab_unselected_pressed_focused_holo" />
        <item android:state_focused="true" android:state_selected="true"  android:state_pressed="true" android:drawable="@drawable/tab_selected_pressed_focused_holo" />
    </selector>

Or you may also try

   <style name="Widget.Holo.ActionBar.TabView" parent="Widget.ActionBar.TabView">
            <item name="android:background">@drawable/tab_indicator_ab_holo</item>
            <item name="android:paddingLeft">16dip</item>
            <item name="android:paddingRight">16dip</item>
        </style>

and tab_indicator_ab_holo.xml

   <selector xmlns:android="http://schemas.android.com/apk/res/android">
        <!-- Non focused states -->
        <item android:state_focused="false" android:state_selected="false" android:state_pressed="false" android:drawable="@color/transparent" />
        <item android:state_focused="false" android:state_selected="true"  android:state_pressed="false" android:drawable="@drawable/tab_selected_holo" />

        <!-- Focused states -->
        <item android:state_focused="true" android:state_selected="false" android:state_pressed="false" android:drawable="@drawable/list_focused_holo" />
        <item android:state_focused="true" android:state_selected="true"  android:state_pressed="false" android:drawable="@drawable/tab_selected_focused_holo" />

        <!-- Pressed -->
        <!--    Non focused states -->
        <item android:state_focused="false" android:state_selected="false" android:state_pressed="true" android:drawable="@drawable/list_pressed_holo_dark" />
        <item android:state_focused="false" android:state_selected="true"  android:state_pressed="true" android:drawable="@drawable/tab_selected_pressed_holo" />

        <!--    Focused states -->
        <item android:state_focused="true" android:state_selected="false" android:state_pressed="true" android:drawable="@drawable/tab_unselected_pressed_holo" />
        <item android:state_focused="true" android:state_selected="true"  android:state_pressed="true" android:drawable="@drawable/tab_selected_pressed_holo" />
    </selector>

Finally using the two png-9 drawables: tab_selected_holo and tab_unselected_holo. They look like the two thicker and thinner blue lines you are talking about.

Or do you mean the minitabs?

 <style name="Widget.ActionBar.TabView" parent="Widget">
        <item name="android:gravity">center_horizontal</item>
        <item name="android:background">@drawable/minitab_lt</item>
        <item name="android:paddingLeft">4dip</item>
        <item name="android:paddingRight">4dip</item>
    </style>

with in minitab_lt.xml

 <selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:state_pressed="true" android:state_selected="true"
          android:drawable="@drawable/minitab_lt_press" />
    <item android:state_selected="true"
          android:drawable="@drawable/minitab_lt_selected" />
    <item android:state_pressed="true"
          android:drawable="@drawable/minitab_lt_unselected_press" />
    <item android:drawable="@drawable/minitab_lt_unselected" />
</selector>

If you need another definition just search for TabWidget in here: https://github.com/android/platform_frameworks_base/blob/master/core/res/res/values/styles.xml

Then as usual define your own style with all the required attributes and drawables…