I've got simple tab activity with next layout:
<TabWidget
android:id="@android:id/tabs"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="#ffffff00" />
<FrameLayout
android:id="@android:id/tabcontent"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="#ffffff00" />
I use buttons as indicators for tabs
tabHost.addTab(tabHost.newTabSpec("Tab1")
.setIndicator(new Button(this))
.setContent(new Intent(this, TabActivity1.class)));
tabHost.addTab(tabHost.newTabSpec("Tab2")
.setIndicator(new Button(this))
.setContent(new Intent(this, TabActivity2.class)));
In this case FrameLayout always got black line and shadow effect on top (you can see it under buttons):
The question is: How can I get rid of this line? Where is the method that draws it in Android sources?
Apply a custom theme to your activity, and null out the android:windowContentOverlay attribute.
Define a theme in themes.xml:
<style name="YourTheme" parent="if you want">
...
<item name="android:windowContentOverlay">@null</item>
...
</style>
Apply the theme on your application or the activity in AndroidManifest.xml:
<application android:theme="@style/YourTheme"
... >
Hope it helps. It caused me lots of headache...