de.zell.android.util.fragments.FragmentReplacer.java Source code

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Here is the source code for de.zell.android.util.fragments.FragmentReplacer.java

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/*
 * Copyright (C) 2015 Christopher Zell <zelldon91@googlemail.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package de.zell.android.util.fragments;

import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import de.zell.android.util.R;

/**
 * Represents a fragment replacer which places a fragment 
 * on a view or layout which is identified via the given id.
 * 
 * @author Christopher Zell <zelldon91@googlemail.com>
 */
public class FragmentReplacer {

    /**
     * The id of the main content view.
     */
    public static final int MAIN_CONTENT = R.id.content_frame;

    /**
     * Replaces the existing fragment on the given view with the new one.
     * If no fragment exists on the view the fragment is only placed.
     * The view is identified via the layout id.
     * 
     * @param fgrMgr the fragment manager which is used to replace the frag
     * @param frg the new fragment which should be placed
     * @param id the view which gets the new fragment
     */
    public static void replace(FragmentManager fgrMgr, Fragment frg, int id) {
        replace(fgrMgr, frg, id, true);
    }

    /**
     * Replaces the existing fragment on the given view with the new one.
     * If no fragment exists on the view the fragment is only placed.
     * The view is identified via the layout id. The backstack flag enables
     * fragment stacking.
     * 
     * @param fgrMgr the fragment manager which is used to replace the frag
     * @param frg the new fragment which should be placed
     * @param id the view which gets the new fragment
     * @param backstack the flag which enables the backstack
     */
    public static void replace(FragmentManager fgrMgr, Fragment frg, int id, boolean backstack) {
        if (fgrMgr == null || frg == null || id <= 0)
            throw new IllegalArgumentException();

        Fragment old = fgrMgr.findFragmentById(id);
        FragmentTransaction trx = fgrMgr.beginTransaction();
        if (old != null) {
            trx.remove(old);
        }
        trx.replace(id, frg);
        if (backstack)
            trx.addToBackStack(null);
        trx.commit();
    }
}