com.jetradar.multibackstack.sample.MainActivity.java Source code

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Here is the source code for com.jetradar.multibackstack.sample.MainActivity.java

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/*
 * Copyright (C) 2016 JetRadar
 *
 * 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 com.jetradar.multibackstack.sample;

import android.app.Activity;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v4.util.Pair;

import com.ashokvarma.bottomnavigation.BottomNavigationBar;
import com.ashokvarma.bottomnavigation.BottomNavigationItem;
import com.jetradar.multibackstack.BackStackActivity;

import static com.ashokvarma.bottomnavigation.BottomNavigationBar.OnTabSelectedListener;

public class MainActivity extends BackStackActivity implements OnTabSelectedListener {
    private static final String STATE_CURRENT_TAB_ID = "current_tab_id";
    private static final int MAIN_TAB_ID = 0;

    private BottomNavigationBar bottomNavBar;
    private Fragment curFragment;
    private int curTabId;

    @Override
    protected void onCreate(Bundle state) {
        super.onCreate(state);
        setContentView(R.layout.activity_main);
        setUpBottomNavBar();

        if (state == null) {
            bottomNavBar.selectTab(MAIN_TAB_ID, false);
            showFragment(rootTabFragment(MAIN_TAB_ID));
        }
    }

    private void setUpBottomNavBar() {
        bottomNavBar = (BottomNavigationBar) findViewById(R.id.bottom_navigation);
        bottomNavBar.addItem(new BottomNavigationItem(R.drawable.dock_home_whiteout, R.string.home))
                .addItem(new BottomNavigationItem(R.drawable.dock_search_whiteout, R.string.search))
                .addItem(new BottomNavigationItem(R.drawable.dock_camera_whiteout, R.string.camera))
                .addItem(new BottomNavigationItem(R.drawable.dock_news_whiteout, R.string.favorites))
                .addItem(new BottomNavigationItem(R.drawable.dock_profile_whiteout, R.string.profile)).initialise();
        bottomNavBar.setTabSelectedListener(this);
    }

    @NonNull
    private Fragment rootTabFragment(int tabId) {
        switch (tabId) {
        case 0:
            BlankFragment blankFragment1 = new BlankFragment();
            return blankFragment1;
        case 1:
            BlankFragment2 blankFragment2 = new BlankFragment2();
            return blankFragment2;
        case 2:
            BlankFragment3 blankFragment3 = new BlankFragment3();
            return blankFragment3;
        case 3:
            BlankFragment4 blankFragment4 = new BlankFragment4();
            return blankFragment4;
        case 4:
            BlankFragment5 blankFragment5 = new BlankFragment5();
            return blankFragment5;
        default:
            throw new IllegalArgumentException();
        }
    }

    @Override
    protected void onRestoreInstanceState(Bundle savedInstanceState) {
        super.onRestoreInstanceState(savedInstanceState);
        curFragment = getSupportFragmentManager().findFragmentById(R.id.content);
        curTabId = savedInstanceState.getInt(STATE_CURRENT_TAB_ID);
        bottomNavBar.selectTab(curTabId, false);
    }

    @Override
    protected void onSaveInstanceState(Bundle outState) {
        outState.putInt(STATE_CURRENT_TAB_ID, curTabId);
        super.onSaveInstanceState(outState);
    }

    @Override
    public void onBackPressed() {
        Pair<Integer, Fragment> pair = popFragmentFromBackStack();
        if (pair != null) {
            backTo(pair.first, pair.second);
        } else {
            super.onBackPressed();
        }
    }

    @Override
    public void onTabSelected(int position) {
        if (curFragment != null) {
            pushFragmentToBackStack(curTabId, curFragment);
        }
        curTabId = position;
        Fragment fragment = popFragmentFromBackStack(curTabId);
        if (fragment == null) {
            fragment = rootTabFragment(curTabId);
        }
        replaceFragment(fragment);
    }

    @Override
    public void onTabReselected(int position) {
        backToRoot();
    }

    @Override
    public void onTabUnselected(int position) {
    }

    public void showFragment(@NonNull Fragment fragment) {
        showFragment(fragment, true);
    }

    public void showFragment(@NonNull Fragment fragment, boolean addToBackStack) {
        if (curFragment != null && addToBackStack) {
            pushFragmentToBackStack(curTabId, curFragment);
        }
        replaceFragment(fragment);
    }

    private void backTo(int tabId, @NonNull Fragment fragment) {
        if (tabId != curTabId) {
            curTabId = tabId;
            bottomNavBar.selectTab(curTabId, false);
        }
        replaceFragment(fragment);
        getSupportFragmentManager().executePendingTransactions();
    }

    private void backToRoot() {
        if (isRootTabFragment(curFragment, curTabId)) {
            return;
        }
        resetBackStackToRoot(curTabId);
        Fragment rootFragment = popFragmentFromBackStack(curTabId);
        assert rootFragment != null;
        backTo(curTabId, rootFragment);
    }

    private boolean isRootTabFragment(@NonNull Fragment fragment, int tabId) {
        return fragment.getClass() == rootTabFragment(tabId).getClass();
    }

    private void replaceFragment(@NonNull Fragment fragment) {
        FragmentManager fm = getSupportFragmentManager();
        FragmentTransaction tr = fm.beginTransaction();
        tr.replace(R.id.content, fragment);
        tr.commitAllowingStateLoss();
        curFragment = fragment;
    }
}