ViewHandler.java

package com.brink.main.Activities;

import java.util.ArrayList;

import android.content.Context;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.util.Log;
import android.view.GestureDetector;
import android.view.GestureDetector.SimpleOnGestureListener;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.widget.HorizontalScrollView;
import android.widget.TabHost;
import android.widget.TabWidget;
import android.widget.TextView;

import com.brink.main.R;
import com.brink.main.Fragments.ActivityFeed;
import com.brink.main.Fragments.Bars;
import com.brink.main.Fragments.Rate;
import com.brink.main.Fragments.TopBars;
import com.brink.main.api.ApiManager;

public class ViewHandler extends FragmentActivity{
	TabHost mTabHost;
    ViewPager  mViewPager;
    TabsAdapter mTabsAdapter;
    public static String TAG = "ViewHandlerActivity";
    static HorizontalScrollView mHorizontalScrollView;
    static int mActiveFeature = 0;
    private static GestureDetector mGestureDetector;
    

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        ApiManager.SetMainActivity(this);
        setContentView(R.layout.mainpage);
        mTabHost = (TabHost)findViewById(android.R.id.tabhost);
        mHorizontalScrollView = (HorizontalScrollView) findViewById(R.id.horizontalscrollview);
        mViewPager = (ViewPager)findViewById(R.id.pager);
        
        
        mTabHost.setup();
        mTabsAdapter = new TabsAdapter(this, mTabHost, mViewPager);

        mTabsAdapter.addTab(mTabHost.newTabSpec("rate"), Rate.RateFragment.class , "Rate");
        mTabsAdapter.addTab(mTabHost.newTabSpec("bars"), Bars.BarsFragment.class, "Bars");
        mTabsAdapter.addTab(mTabHost.newTabSpec("activityfeed"), ActivityFeed.FeedFragment.class, "Activity");
        mTabsAdapter.addTab(mTabHost.newTabSpec("topbars"), TopBars.TopBarsFragment.class, "Top Bars");
        
        mTabsAdapter.mTabHost.setCurrentTabByTag("Activity");

        if (savedInstanceState != null) {
            mTabHost.setCurrentTabByTag(savedInstanceState.getString("tab"));
        }
        
       
    }

    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        outState.putString("tab", mTabHost.getCurrentTabTag());
    }


    public static class TabsAdapter extends FragmentPagerAdapter 
            implements TabHost.OnTabChangeListener, ViewPager.OnPageChangeListener {
        private final Context mContext;
        private final TabHost mTabHost;
        private final ViewPager mViewPager;
        private final ArrayList<TabInfo> mTabs = new ArrayList<TabInfo>();


        static final class TabInfo {
            private final String tag;
            private final Class<?> clss;
            private final Bundle args;

            TabInfo(String _tag, Class<?> _class, Bundle _args) {
                tag = _tag;
                clss = _class;
                args = _args;
            }
        }

        static class DummyTabFactory implements TabHost.TabContentFactory {
            private final Context mContext;

            public DummyTabFactory(Context context) {
                mContext = context;
            }

            
            public View createTabContent(String tag) {
                View v = new View(mContext);
                v.setMinimumWidth(0);
                v.setMinimumHeight(0);
                return v;
            }
        }
        

        public TabsAdapter(FragmentActivity activity, TabHost tabHost, ViewPager pager) {
            super(activity.getSupportFragmentManager());
            mContext = activity;
            mTabHost = tabHost;
            mViewPager = pager;
            mTabHost.setOnTabChangedListener(this);
            mViewPager.setAdapter(this);
            mViewPager.setOnPageChangeListener(this);
            mHorizontalScrollView.setOnTouchListener(new View.OnTouchListener() {
				
				public boolean onTouch(View v, MotionEvent event) {
					if(mGestureDetector.onTouchEvent(event))
					{
						Log.i(TAG, "TabsAdapter-onTouch Case 1");
						return true;
					}
					else if(event.getAction() == MotionEvent.ACTION_UP || event.getAction() == MotionEvent.ACTION_CANCEL)
					{
						Log.i(TAG, "TabsAdapter-onTouch Case 2");
						int scrollX = mHorizontalScrollView.getScrollX();
						int featureWidth = v.getMeasuredWidth();
						mActiveFeature = ((scrollX + (featureWidth/2))/featureWidth);
						int scrollTo = mActiveFeature*featureWidth;
						mHorizontalScrollView.smoothScrollTo(scrollTo,0);
						return true;
					}
					else
					{
						Log.i(TAG, "TabsAdapter-onTouch Case 3");
						return false;
					}
				}	
				
            });
            mGestureDetector = new GestureDetector(new MyGestureDetector());
        }
        
        
        public class MyGestureDetector extends SimpleOnGestureListener 
    	{

            @Override
            public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {

                try {
                    //right to left
                    if(velocityX < 0 && Math.abs(velocityX) > 300) {
                    	Log.i(TAG, "MyGestureDetector - Processing onFling RtoL");
                        int featureWidth = mHorizontalScrollView.getMeasuredWidth();
                        mHorizontalScrollView.smoothScrollTo(mActiveFeature*featureWidth, 0);
                        return true;
                    }
                    //left to right
                    else if (velocityX > 0 && Math.abs(velocityX) > 300) {
                    	Log.i(TAG, "MyGestureDetector - Processing onFling LtoR");
                        int featureWidth = mHorizontalScrollView.getMeasuredWidth();
                        mActiveFeature = (mActiveFeature > 0)? mActiveFeature - 1:0;
                        mHorizontalScrollView.smoothScrollTo(mActiveFeature*featureWidth, 0);
                        return true;
                    }
                } catch (Exception e) {
                        Log.e("Fling", "There was an error processing the Fling event:" + e.getMessage());
                }
                return false;
            }
        }

        public void addTab(TabHost.TabSpec tabSpec, Class<?> clss, String tabName) {
            tabSpec.setContent(new DummyTabFactory(mContext));
            String tag = tabSpec.getTag();
            TabInfo info = new TabInfo(tag, clss, null);
            mTabs.add(info);
            tabSpec.setIndicator(prepareTab(mTabHost.getContext(), tabName));
            mTabHost.addTab(tabSpec);
            notifyDataSetChanged();
        }
        
        public static View prepareTab(Context context, String text)
        {
        	View view = LayoutInflater.from(context).inflate(R.layout.tabs_main,null);
        	TextView tabText = (TextView) view.findViewById(R.id.tabsText);
        	tabText.setText(text);
        	return view;
        }

        
        public int getCount() {
            return mTabs.size();
        }

        
        public Fragment getItem(int position) {
            TabInfo info = mTabs.get(position);
            return Fragment.instantiate(mContext, info.clss.getName(), info.args);
        }

        public void onTabChanged(String tabId) {
            int position = mTabHost.getCurrentTab();
            mViewPager.setCurrentItem(position);
            mHorizontalScrollView.scrollTo(position, 0);
            mHorizontalScrollView.refreshDrawableState();
        }

       
        public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
        	mHorizontalScrollView.scrollTo(position, 0);
        	mHorizontalScrollView.refreshDrawableState();
        }

      
        public void onPageSelected(int position) {
            // Unfortunately when TabHost changes the current tab, it kindly
            // also takes care of putting focus on it when not in touch mode.
            // The jerk.
            // This hack tries to prevent this from pulling focus out of our
            // ViewPager.
            TabWidget widget = mTabHost.getTabWidget();
            int oldFocusability = widget.getDescendantFocusability();
            widget.setDescendantFocusability(ViewGroup.FOCUS_BLOCK_DESCENDANTS);
            mTabHost.setCurrentTab(position);
            widget.setDescendantFocusability(oldFocusability);
        }

        public void onPageScrollStateChanged(int state) {
        	
        }
    }

    	
    
}