Java tutorial
/* * Copyright (C) 2017 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 android.app; import android.content.Context; import android.os.Bundle; import android.os.Parcel; import android.os.Parcelable; import android.util.Log; final class FragmentState implements Parcelable { final String mClassName; final int mIndex; final boolean mFromLayout; final int mFragmentId; final int mContainerId; final String mTag; final boolean mRetainInstance; final boolean mDetached; final Bundle mArguments; final boolean mHidden; Bundle mSavedFragmentState; Fragment mInstance; FragmentState(Fragment frag) { mClassName = frag.getClass().getName(); mIndex = frag.mIndex; mFromLayout = frag.mFromLayout; mFragmentId = frag.mFragmentId; mContainerId = frag.mContainerId; mTag = frag.mTag; mRetainInstance = frag.mRetainInstance; mDetached = frag.mDetached; mArguments = frag.mArguments; mHidden = frag.mHidden; } FragmentState(Parcel in) { mClassName = in.readString(); mIndex = in.readInt(); mFromLayout = in.readInt() != 0; mFragmentId = in.readInt(); mContainerId = in.readInt(); mTag = in.readString(); mRetainInstance = in.readInt() != 0; mDetached = in.readInt() != 0; mArguments = in.readBundle(); mHidden = in.readInt() != 0; mSavedFragmentState = in.readBundle(); } public Fragment instantiate(FragmentHostCallback host, FragmentContainer container, Fragment parent, FragmentManagerNonConfig childNonConfig) { if (mInstance == null) { final Context context = host.getContext(); if (mArguments != null) { mArguments.setClassLoader(context.getClassLoader()); } if (container != null) { mInstance = container.instantiate(context, mClassName, mArguments); } else { mInstance = Fragment.instantiate(context, mClassName, mArguments); } if (mSavedFragmentState != null) { mSavedFragmentState.setClassLoader(context.getClassLoader()); mInstance.mSavedFragmentState = mSavedFragmentState; } mInstance.setIndex(mIndex, parent); mInstance.mFromLayout = mFromLayout; mInstance.mRestored = true; mInstance.mFragmentId = mFragmentId; mInstance.mContainerId = mContainerId; mInstance.mTag = mTag; mInstance.mRetainInstance = mRetainInstance; mInstance.mDetached = mDetached; mInstance.mHidden = mHidden; mInstance.mFragmentManager = host.mFragmentManager; if (FragmentManagerImpl.DEBUG) { Log.v(FragmentManagerImpl.TAG, "Instantiated fragment " + mInstance); } } mInstance.mChildNonConfig = childNonConfig; return mInstance; } @Override public int describeContents() { return 0; } @Override public void writeToParcel(Parcel dest, int flags) { dest.writeString(mClassName); dest.writeInt(mIndex); dest.writeInt(mFromLayout ? 1 : 0); dest.writeInt(mFragmentId); dest.writeInt(mContainerId); dest.writeString(mTag); dest.writeInt(mRetainInstance ? 1 : 0); dest.writeInt(mDetached ? 1 : 0); dest.writeBundle(mArguments); dest.writeInt(mHidden ? 1 : 0); dest.writeBundle(mSavedFragmentState); } public static final Parcelable.Creator<FragmentState> CREATOR = new Parcelable.Creator<FragmentState>() { @Override public FragmentState createFromParcel(Parcel in) { return new FragmentState(in); } @Override public FragmentState[] newArray(int size) { return new FragmentState[size]; } }; }