org.droid2droid.ui.TabsAdapter.java Source code

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Here is the source code for org.droid2droid.ui.TabsAdapter.java

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/******************************************************************************
 *
 * droid2droid - Distributed Android Framework
 * ==========================================
 *
 * Copyright (C) 2012 by Atos (http://www.http://atos.net)
 * http://www.droid2droid.org
 *
 ******************************************************************************
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 *
******************************************************************************/
package org.droid2droid.ui;

import java.util.ArrayList;

import org.droid2droid.RAApplication;

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.app.FragmentTransaction;
import android.support.v4.view.ViewPager;

import com.actionbarsherlock.app.ActionBar;
import com.actionbarsherlock.app.ActionBar.Tab;

/**
 * This is a helper class that implements the management of tabs and all details
 * of connecting a ViewPager with associated TabHost. It relies on a trick.
 * Normally a tab host has a simple API for supplying a View or Intent that each
 * tab will show. This is not sufficient for switching between pages. So instead
 * we make the content part of the tab host 0dp high (it is not shown) and the
 * TabsAdapter supplies its own dummy view to show as the tab content. It
 * listens to changes in tabs, and takes care of switch to the correct paged in
 * the ViewPager whenever the selected tab changes.
 */
public final class TabsAdapter extends FragmentPagerAdapter
        implements ViewPager.OnPageChangeListener, ActionBar.TabListener {
    private final FragmentActivity mContext;

    private final ActionBar mActionBar;

    private final ViewPager mViewPager;

    private static final class TabInfo {
        private final Class<?> mClss;

        private final Bundle mArgs;
        AbstractBodyFragment mFragment;

        TabInfo(Class<?> clazz, Bundle args) {
            mClss = clazz;
            mArgs = args;
        }
    }

    private final ArrayList<TabInfo> mTabs = new ArrayList<TabInfo>();

    public TabsAdapter(FragmentActivity activity, ActionBar actionBar, ViewPager pager) {
        super(activity.getSupportFragmentManager());
        mContext = activity;
        mActionBar = actionBar;
        mViewPager = pager;
        mViewPager.setAdapter(this);
        mViewPager.setOnPageChangeListener(this);
    }

    public void addTab(ActionBar.Tab tab, Class<?> clss, Bundle args) {
        TabInfo info = new TabInfo(clss, args);
        tab.setTag(info);
        tab.setTabListener(this);
        mTabs.add(info);
        if (mActionBar != null)
            mActionBar.addTab(tab.setTabListener(this));
        notifyDataSetChanged();
    }

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

    @Override
    public Fragment getItem(int position) {
        TabInfo info = mTabs.get(position);
        if (info.mFragment == null) {
            info.mFragment = (AbstractBodyFragment) Fragment.instantiate(mContext, info.mClss.getName(),
                    info.mArgs);
        }
        return info.mFragment;
    }

    @Override
    public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
    }

    @Override
    public void onPageSelected(int position) {
        if (mActionBar != null)
            mActionBar.setSelectedNavigationItem(position); // onPageSelected() invoked by side effect
    }

    @Override
    public void onPageScrollStateChanged(int state) {
    }

    @Override
    public void onTabSelected(Tab tab, FragmentTransaction fft) {
        RAApplication.hideSoftKeyboard(mContext);
        mContext.setProgressBarIndeterminateVisibility(false);
        FragmentTransaction ft = fft;
        if (ft == null)
            ft = mContext.getSupportFragmentManager().beginTransaction();
        mViewPager.setCurrentItem(tab.getPosition());
        if (fft == null)
            ft.commit();
        ((AbstractBodyFragment) getItem(tab.getPosition())).onPageSelected();
    }

    @Override
    public void onTabReselected(Tab tab, FragmentTransaction ft) {
        ((AbstractBodyFragment) getItem(tab.getPosition())).onPageReSelected();
    }

    @Override
    public void onTabUnselected(Tab tab, FragmentTransaction ft) {
        ((AbstractBodyFragment) getItem(tab.getPosition())).onPageUnselected();
    }

    final AbstractBodyFragment getActiveFragment() {
        return mTabs.get(mViewPager.getCurrentItem()).mFragment;
    }
}