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/*
* Copyright (C) 2016 The Android Open Source Project
* Copyright (C) 2020 The LineageOS Project
*
* 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.android.deskclock;
import android.util.ArrayMap;
import android.view.View;
import android.view.ViewGroup;
import androidx.fragment.app.Fragment;
import androidx.fragment.app.FragmentManager;
import androidx.fragment.app.FragmentTransaction;
import com.android.deskclock.uidata.UiDataModel;
import java.util.Map;
/**
* This class produces the DeskClockFragments that are the content of the DeskClock tabs.
* It presents the tabs in LTR and RTL order depending on the text layout direction for the
* current locale. To prevent issues when switching between LTR and RTL, fragments are registered
* with the manager using position-independent tags, which is an important departure from
* FragmentPagerAdapter.
*/
public final class FragmentUtils {
private final DeskClock mDeskClock;
/** The manager into which fragments are added. */
private final FragmentManager mFragmentManager;
/** A fragment cache that can be accessed before {@link #instantiateItem} is called. */
private final Map<UiDataModel.Tab, DeskClockFragment> mFragmentCache;
/** The current fragment displayed to the user. */
private DeskClockFragment mCurrentPrimaryItem;
public FragmentUtils(DeskClock deskClock) {
mDeskClock = deskClock;
mFragmentCache = new ArrayMap<>(getCount());
mFragmentManager = deskClock.getSupportFragmentManager();
}
private int getCount() {
return UiDataModel.getUiDataModel().getTabCount();
}
public DeskClockFragment getDeskClockFragment(UiDataModel.Tab tab) {
// First check the local cache for the fragment.
DeskClockFragment fragment = mFragmentCache.get(tab);
if (fragment != null) {
return fragment;
}
// Next check the fragment manager; relevant when app is rebuilt after locale changes
// because this adapter will be new and mFragmentCache will be empty, but the fragment
// manager will retain the Fragments built on original application launch.
fragment = (DeskClockFragment) mFragmentManager.findFragmentByTag(tab.name());
if (fragment != null) {
fragment.setFabContainer(mDeskClock);
mFragmentCache.put(tab, fragment);
return fragment;
}
// Otherwise, build the fragment from scratch.
final String fragmentClassName = tab.getFragmentClassName();
fragment = (DeskClockFragment) Fragment.instantiate(mDeskClock, fragmentClassName);
fragment.setFabContainer(mDeskClock);
FragmentTransaction transaction = mFragmentManager.beginTransaction();
transaction.add(R.id.fragment_container, fragment, tab.name());
transaction.commit();
mFragmentCache.put(tab, fragment);
return fragment;
}
public void hideAllFragments() {
FragmentTransaction transaction = mFragmentManager.beginTransaction();
for (UiDataModel.Tab tab : UiDataModel.Tab.values()) {
Fragment fragment = mFragmentManager.findFragmentByTag(tab.name());
if (fragment != null) {
transaction.hide(fragment);
}
}
transaction.commit();
}
public void showFragment(UiDataModel.Tab tab) {
hideAllFragments();
Fragment fragment = getDeskClockFragment(tab);
mFragmentManager.beginTransaction().show(fragment).commit();
mCurrentPrimaryItem = (DeskClockFragment) fragment;
}
public DeskClockFragment getCurrentFragment() {
return mCurrentPrimaryItem;
}
}
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