| /* |
| * Copyright (C) 2014 The Android Open Source 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.timer; |
| |
| import android.app.Fragment; |
| import android.app.FragmentManager; |
| import android.app.FragmentTransaction; |
| import android.support.v13.app.FragmentCompat; |
| import android.support.v13.app.FragmentStatePagerAdapter; |
| import android.support.v4.util.SparseArrayCompat; |
| import android.support.v4.view.PagerAdapter; |
| import android.view.View; |
| import android.view.ViewGroup; |
| |
| /** |
| * Forked from support lib's {@link FragmentStatePagerAdapter}, with some minor |
| * changes that couldn't be accomplished through subclassing: we need to override the |
| * onDataSetChanged method using the private member mFragments which cannot be accessed outside. |
| * |
| * This class is used for TimerFragment's vertical view pager only. It removed the save/restore |
| * functionality, because all the fragments needs to be destroyed whenever TimerFragment's |
| * onPause, in order to bind the newly created timer view with the new pager fragment. |
| */ |
| public abstract class FragmentStatePagerAdapter2 extends PagerAdapter { |
| |
| private final FragmentManager mFragmentManager; |
| private FragmentTransaction mCurTransaction = null; |
| |
| private SparseArrayCompat<Fragment> mFragments = new SparseArrayCompat<Fragment>(); |
| private Fragment mCurrentPrimaryItem = null; |
| |
| |
| public FragmentStatePagerAdapter2(FragmentManager fm) { |
| mFragmentManager = fm; |
| } |
| |
| /** |
| * Return the Fragment associated with a specified position. |
| */ |
| public abstract Fragment getItem(int position); |
| |
| @Override |
| public void startUpdate(ViewGroup container) { |
| } |
| |
| @Override |
| public Object instantiateItem(ViewGroup container, int position) { |
| // If we already have this item instantiated, there is nothing |
| // to do. This can happen when we are restoring the entire pager |
| // from its saved state, where the fragment manager has already |
| // taken care of restoring the fragments we previously had instantiated. |
| final Fragment existing = mFragments.get(position); |
| if (existing != null) { |
| return existing; |
| } |
| |
| if (mCurTransaction == null) { |
| mCurTransaction = mFragmentManager.beginTransaction(); |
| } |
| |
| Fragment fragment = getItem(position); |
| if (fragment != mCurrentPrimaryItem) { |
| setItemVisible(fragment, false); |
| } |
| mFragments.put(position, fragment); |
| mCurTransaction.add(container.getId(), fragment); |
| |
| return fragment; |
| } |
| |
| @Override |
| public void destroyItem(ViewGroup container, int position, Object object) { |
| Fragment fragment = (Fragment) object; |
| |
| if (mCurTransaction == null) { |
| mCurTransaction = mFragmentManager.beginTransaction(); |
| } |
| mFragments.delete(position); |
| |
| mCurTransaction.remove(fragment); |
| } |
| |
| @Override |
| public void setPrimaryItem(ViewGroup container, int position, Object object) { |
| Fragment fragment = (Fragment) object; |
| if (fragment != mCurrentPrimaryItem) { |
| if (mCurrentPrimaryItem != null) { |
| setItemVisible(mCurrentPrimaryItem, false); |
| } |
| if (fragment != null) { |
| setItemVisible(fragment, true); |
| } |
| mCurrentPrimaryItem = fragment; |
| } |
| } |
| |
| @Override |
| public void finishUpdate(ViewGroup container) { |
| if (mCurTransaction != null) { |
| mCurTransaction.commitAllowingStateLoss(); |
| mCurTransaction = null; |
| mFragmentManager.executePendingTransactions(); |
| } |
| } |
| |
| @Override |
| public boolean isViewFromObject(View view, Object object) { |
| return ((Fragment) object).getView() == view; |
| } |
| |
| public void setItemVisible(Fragment item, boolean visible) { |
| FragmentCompat.setMenuVisibility(item, visible); |
| FragmentCompat.setUserVisibleHint(item, visible); |
| } |
| |
| @Override |
| public void notifyDataSetChanged() { |
| // update positions in mFragments |
| SparseArrayCompat<Fragment> newFragments = |
| new SparseArrayCompat<Fragment>(mFragments.size()); |
| for (int i = 0; i < mFragments.size(); i++) { |
| final int oldPos = mFragments.keyAt(i); |
| final Fragment f = mFragments.valueAt(i); |
| final int newPos = getItemPosition(f); |
| |
| if (newPos != POSITION_NONE) { |
| final int pos = (newPos >= 0) ? newPos : oldPos; |
| newFragments.put(pos, f); |
| } |
| } |
| mFragments = newFragments; |
| |
| super.notifyDataSetChanged(); |
| } |
| |
| public Fragment getFragmentAt(int position) { |
| return mFragments.valueAt(position); |
| } |
| |
| } |