How to remove top and bottom padding from android.

Question

I am trying to place a SlidingTabLayout inside my android.support.v7.widget.Toolbar but for some reason there is extra top and bottom padding in portrait layout. As shown in this screenshot:

In landscape layout the android.support.v7.widget.Toolbar is shorter and the extra padding is gone:

I am aware of the contentInsertStart and contentInsetEnd attributes but there does not appear to be anything for top and bottom. Here is my layout:

<android.support.design.widget.AppBarLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_height="wrap_content"
    android:layout_width="match_parent"
    android:theme="?attr/actionBarTheme"
    >

    <!-- Changing the size of the toolbar fixed the problem below but I don't like the solution since the height difference is perceptible -->
    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="?attr/colorPrimary"
        android:padding="0dp"
        app:popupTheme="?attr/actionBarPopupTheme"
        >

        <!-- TODO: BUG - This isn't filling out the action bar in portrait (see note above) -->
        <com.myapplication.views.widgets.SlidingTabLayout
            android:id="@+id/sliding_tabs"
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:background="@color/pink_400"
            />

    </android.support.v7.widget.Toolbar>

</android.support.design.widget.AppBarLayout>

As indicated in the comments if I manually set the height of the android.support.v7.widget.Toolbar to 48dp then the SlidingTabLayout fills it out but there are two problems here:

1. The toolbar is a different height than the standard toolbar which is noticeable when changing activities.
2. The icons in the Toolbar are no longer vertically centered if I change it's height

So as the title says, how do I remove top and bottom padding from android.support.v7.widget.Toolbar?

Answer 1

Ok so @RaviSravanKumar comment helped me figure this out. When I changed my layout back to:

<android.support.design.widget.AppBarLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_height="wrap_content"
    android:layout_width="match_parent"
    android:theme="?attr/actionBarTheme"
    >

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        android:background="?attr/colorPrimary"
        app:popupTheme="?attr/actionBarPopupTheme"
        >

        <com.myapplication.views.widgets.SlidingTabLayout
            android:id="@+id/sliding_tabs"
            android:layout_width="wrap_content"
            android:layout_height="?attr/actionBarSize"
            />

    </android.support.v7.widget.Toolbar>

</android.support.design.widget.AppBarLayout>

With the heights set to ?attr/actionBarSize I noticed the SlidingTabLayout was actually filling the entire height. I only noticed this because of the pink background I had set for debugging.

The reason I missed this originally was because the underline indicator was still not at the bottom (as shown in the screenshot in the original question). I had to make the following changes to the SlidingTabLayout code:

Original:

public SlidingTabLayout(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);

    // Disable the Scroll Bar
    setHorizontalScrollBarEnabled(false);
    // Make sure that the Tab Strips fills this View
    setFillViewport(true);

    mTitleOffset = (int) (TITLE_OFFSET_DIPS * getResources().getDisplayMetrics().density);

    mTabStrip = new SlidingTabStrip(context);
    addView(mTabStrip, LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
}

New: (note the change from LayoutParams.WRAP_CONTENT to LayoutParams.MATCH_PARENT:

public SlidingTabLayout(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);

    // Disable the Scroll Bar
    setHorizontalScrollBarEnabled(false);
    // Make sure that the Tab Strips fills this View
    setFillViewport(true);

    mTitleOffset = (int) (TITLE_OFFSET_DIPS * getResources().getDisplayMetrics().density);

    mTabStrip = new SlidingTabStrip(context);
    addView(mTabStrip, LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
}

Original:

protected TextView createDefaultTabView(Context context) {
    TextView textView = new TextView(context);
    textView.setGravity(Gravity.CENTER);
    textView.setTextSize(TypedValue.COMPLEX_UNIT_SP, TAB_VIEW_TEXT_SIZE_SP);
    textView.setTypeface(Typeface.DEFAULT_BOLD);
    textView.setLayoutParams(new LinearLayout.LayoutParams(
            ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT));

    TypedValue outValue = new TypedValue();
    getContext().getTheme().resolveAttribute(android.R.attr.selectableItemBackground,
            outValue, true);
    textView.setBackgroundResource(outValue.resourceId);

    if (Build.VERSION.SDK_INT >= 14) {
        textView.setAllCaps(true);
    }

    int padding = (int) (TAB_VIEW_PADDING_DIPS * getResources().getDisplayMetrics().density);
    textView.setPadding(padding, padding, padding, padding);

    return textView;
}

New: (note the change to the layout params and padding)

protected TextView createDefaultTabView(Context context) {
    TextView textView = new TextView(context);
    textView.setGravity(Gravity.CENTER);
    textView.setTextSize(TypedValue.COMPLEX_UNIT_SP, TAB_VIEW_TEXT_SIZE_SP);
    textView.setTypeface(Typeface.DEFAULT_BOLD);
    textView.setLayoutParams(new LinearLayout.LayoutParams(
            ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.MATCH_PARENT));

    TypedValue outValue = new TypedValue();
    getContext().getTheme().resolveAttribute(android.R.attr.selectableItemBackground,
            outValue, true);
    textView.setBackgroundResource(outValue.resourceId);

    if (Build.VERSION.SDK_INT >= 14) {
        textView.setAllCaps(true);
    }

    int padding = (int) (TAB_VIEW_PADDING_DIPS * getResources().getDisplayMetrics().density);
    textView.setPadding(padding, 0, padding, 0);

    return textView;
}