Add Icons to SlidingTabLayout instead of Text

Question

I'm implementing a SlidingTabLayout in my android application. What my query is that I'd like to implement icons in my Sliding Tabs instead of texts for navigation. I searched heavily on the internet for any such tutorial or sample but found none. I also searched a previous question on stackoverflow: Over Here - SlidingTabLayout with Icons. It was slightly informative but didn't really help me out.

To be clear. I require my tabs to consist of icons only. No text.

As I am new to this whole setup, I'd appreciate if you'd post proper code with an explanation. Thank you for your time and effort!

P.S. I also heard about the pagerslidingtabstrip by Andreaz Stuetz and wondered if that would be more suitable for the type of thing I'm going for...

Also: Here is what I would like my sliding tabs to look like. Check out the top of this image.

EDIT : NOW THAT LOLLIPOP (WITH MATERIAL DESIGN) HAS COME OUT. I HAVE SEEN A LOT OF APPS USING A NEW "ONLY ICON" SLIDING-TAB-LAYOUT BELOW THEIR TOOLBAR (ANDROID 5.0 ACTION-BAR). IS THEIR ANY NEW WAY TO IMPLEMENT THIS?? THANKS ONCE AGAIN!

Answer 1

The key to this is to return a SpannableString, containing your icon in an ImageSpan, from your PagerAdapter's getPageTitle(position) method:

private int[] imageResId = {
        R.drawable.ic_tab_notifications,
        R.drawable.ic_tab_weather,
        R.drawable.ic_tab_calendar
};

@Override
public CharSequence getPageTitle(int position) {
    Drawable image = getResources().getDrawable(imageResId[position]);
    image.setBounds(0, 0, image.getIntrinsicWidth(), image.getIntrinsicHeight());
    SpannableString sb = new SpannableString(" ");
    ImageSpan imageSpan = new ImageSpan(image, ImageSpan.ALIGN_BOTTOM);
    sb.setSpan(imageSpan, 0, 1, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
    return sb;
}

Normally this be would be enough, but the default tab created by SlidingTabLayout makes a call to TextView#setAllCaps(true) which effectively disables all ImageSpans, so you'll have to use a custom tab view instead:

res/layout/custom_tab.xml

<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textSize="12sp"
    android:textStyle="bold"
    android:background="?android:selectableItemBackground"
    android:padding="16dp"
    />

and where ever you setup/bind to your ViewPager:

SlidingTabLayout slidingTabLayout = (SlidingTabLayout) view.findViewById(R.id.sliding_tabs);
slidingTabLayout.setCustomTabView(R.layout.custom_tab, 0);
slidingTabLayout.setViewPager(viewPager);

(make sure to call setCustomTabView before setViewPager)

Answer 2

I solved same problem, but also with changing drawable on selected tab.

Create your drawables for tabs, with two states. first_tab_drawable.xml, second_tab_drawable.xml, third_tab_drawable.xml:

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:drawable="@drawable/ic_selected" android:state_selected="true"/>
    <item android:drawable="@drawable/ic_normal"/>
</selector>

Create your own pager adapter, extends from PagerAdapter:

public class MyPagerAdapter extends PagerAdapter {

    private int[] drawablesIds = {
        R.drawable.first_tab_drawable,
        R.drawable.second_tab_drawable,
        R.drawable.third_tab_drawable
    };

    //Constructor and other standard funcs...

    public int getDrawableId(int position){
        //Here is only example for getting tab drawables
        return drawablesIds[position];
    }
    //...
}

Change code of SlidingTabLayout:

private void populateTabStrip() {
    //Here is no more standard PagerAdapter!
    final MyPagerAdapter adapter = (MyPagerAdapter) mViewPager.getAdapter();

    final View.OnClickListener tabClickListener = new TabClickListener();

    for (int i = 0; i < adapter.getCount(); i++) {
        View tabView = null;
        TextView tabTitleView = null;

        if (mTabViewLayoutId != 0) {
            // If there is a custom tab view layout id set, try and inflate it
            tabView = LayoutInflater.from(getContext()).inflate(mTabViewLayoutId, mTabStrip,
                    false);
            tabTitleView = (TextView) tabView.findViewById(mTabViewTextViewId);
        }

        if (tabView == null) {
            tabView = createDefaultTabView(getContext());
        }

        if (tabTitleView == null && TextView.class.isInstance(tabView)) {
            tabTitleView = (TextView) tabView;
        }

        //Set icon, that can be changeable instead setting text.
        //I think the text also can setting here from getPageTitle func.
        //But we interesting only in icon
        tabTitleView.setCompoundDrawablesWithIntrinsicBounds(adapter.getDrawableId(i), 0, 0, 0);
        //Select tab if it is current
        if (mViewPager.getCurrentItem() == i){
            tabView.setSelected(true);
        }
        tabView.setOnClickListener(tabClickListener);

        mTabStrip.addView(tabView);
    }
}

And make really selected TextView title also in SlidingTabLayout in InternalViewPagerListener:

    @Override
    public void onPageSelected(int position) {

        //Clear old selection and make new
        for(int i = 0; i < mTabStrip.getChildCount(); i ++){
            mTabStrip.getChildAt(i).setSelected(false);
        }
        mTabStrip.getChildAt(position).setSelected(true);

        if (mScrollState == ViewPager.SCROLL_STATE_IDLE) {
            mTabStrip.onViewPagerPageChanged(position, 0f);
            scrollToTab(position, 0);
        }

        if (mViewPagerPageChangeListener != null) {
            mViewPagerPageChangeListener.onPageSelected(position);
        }
    }

Hope it will be helpful for somebody.