Java 定义全局变量在Android Studio中失败
我正在这里学习“检索联系人姓名”教程： 我能够按照要求导入以下内容：Java 定义全局变量在Android Studio中失败,java,android-contacts,Java,Android Contacts,我正在这里学习“检索联系人姓名”教程： 我能够按照要求导入以下内容： import android.provider.ContactsContract; import android.support.v4.app.Fragment; import android.support.v4.app.LoaderManager.LoaderCallbacks; import android.widget.AdapterView; public class ContactsFragment extend
import android.provider.ContactsContract;
import android.support.v4.app.Fragment;
import android.support.v4.app.LoaderManager.LoaderCallbacks;
import android.widget.AdapterView;
public class ContactsFragment extends Fragment implements
LoaderManager.LoaderCallbacks<Cursor>,
AdapterView.OnItemClickListener {
}
apply plugin: 'com.android.application'
repositories {
mavenLocal()
flatDir {
dirs 'libs'
}
}
android {
compileSdkVersion 25
buildToolsVersion "25.0.2"
defaultConfig {
applicationId "com.google.firebase.codelab.friendlychat"
minSdkVersion 14
targetSdkVersion 25
versionCode 1
versionName "1.0"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
packagingOptions {
exclude 'META-INF/LICENSE'
exclude 'META-INF/LICENSE-FIREBASE.txt'
exclude 'META-INF/NOTICE'
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
compile 'com.android.support:design:25.1.1'
compile 'com.github.bumptech.glide:glide:3.7.0'
compile 'de.hdodenhof:circleimageview:1.3.0'
compile 'com.android.support:appcompat-v7:25.1.1'
compile 'com.google.android.gms:play-services-auth:10.2.0'
compile 'com.google.firebase:firebase-database:10.2.0'
compile 'com.google.firebase:firebase-storage:10.2.0'
compile 'com.google.firebase:firebase-auth:10.2.0'
compile 'com.google.firebase:firebase-config:10.2.0'
compile 'com.google.android.gms:play-services-appinvite:10.2.0'
compile 'com.google.firebase:firebase-messaging:10.2.0'
compile 'com.google.android.gms:play-services-ads:10.2.0'
compile 'com.google.firebase:firebase-crash:10.2.0'
compile 'com.google.firebase:firebase-appindexing:10.2.0'
compile 'com.firebaseui:firebase-ui-database:0.4.0'
compile 'com.android.support.constraint:constraint-layout:1.0.2'
testCompile 'junit:junit:4.12'
androidTestCompile 'junit:junit:4.12'
androidTestCompile 'com.android.support.test.espresso:espresso-core:2.2.2'
androidTestCompile 'com.android.support.test:runner:0.5'
androidTestCompile 'com.android.support:support-annotations:25.1.1'
}
apply plugin: 'com.google.gms.google-services'
// Empty public constructor, required by the system
public ContactsFragment() {}
// A UI Fragment must inflate its View
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the fragment layout
return inflater.inflate(R.layout.contact_list_fragment,
container, false);
}
class ContactsFragment extends Fragment implements
LoaderManager.LoaderCallbacks<Cursor>,
AdapterView.OnItemClickListener {
@Override
public Loader<Cursor> onCreateLoader(int id, Bundle args) {
return null;
}
@Override
public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
}
@Override
public void onLoaderReset(Loader<Cursor> loader) {
}
/**
* Callback method to be invoked when an item in this AdapterView has
* been clicked.
* <p>
* Implementers can call getItemAtPosition(position) if they need
* to access the data associated with the selected item.
*
* @param parent The AdapterView where the click happened.
* @param view The view within the AdapterView that was clicked (this
* will be a view provided by the adapter)
* @param position The position of the view in the adapter.
* @param id The row id of the item that was clicked.
*/
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
}
}
//空的公共构造函数，系统需要
公共联系人片段（）{}
//UI片段必须膨胀其视图
@凌驾
创建视图上的公共视图（布局、充气机、视图组容器、，
Bundle savedInstanceState）{
//膨胀碎片布局
返回充气机。充气（右布局。联系列表），
货柜(虚假);；
}
类ContactsFragment扩展了片段实现
LoaderManager.LoaderCallbacks，
AdapterView.OnItemClickListener{
@凌驾
公共加载器onCreateLoader（int-id，Bundle-args）{
返回null；
}
@凌驾
public void onLoadFinished（加载器、光标数据）{
}
@凌驾
公共void onLoaderReset（加载器）{
}
/**
*当此AdapterView中的项已被删除时调用的回调方法
*被点击了。
*
*如果需要，实现者可以调用getItemAtPosition（position）
*访问与所选项目关联的数据。
*
*@param parent发生单击的AdapterView。
*@param view单击的AdapterView中的视图（此
*将是适配器提供的视图）
*@param position视图在适配器中的位置。
*@param id单击的项目的行id。
*/
@凌驾
public void onItemClick（AdapterView父对象、视图、整型位置、长id）{
}
}
package com.google.firebase.codelab.friendlychat;
import android.annotation.SuppressLint;
import android.content.Context;
import android.content.CursorLoader;
import android.content.Intent;
import android.content.SharedPreferences;
import android.database.Cursor;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.support.annotation.NonNull;
import android.support.v4.app.LoaderManager;
import android.support.v4.content.ContextCompat;
import android.support.v4.content.Loader;
import android.support.v4.widget.SimpleCursorAdapter;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.text.Editable;
import android.text.InputFilter;
import android.text.TextWatcher;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.CursorAdapter;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.ProgressBar;
import android.widget.TextView;
import com.bumptech.glide.Glide;
import com.firebase.ui.database.FirebaseRecyclerAdapter;
import com.google.android.gms.ads.AdRequest;
import com.google.android.gms.ads.AdView;
import com.google.android.gms.appinvite.AppInviteInvitation;
import com.google.android.gms.auth.api.Auth;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.OnFailureListener;
import com.google.android.gms.tasks.OnSuccessListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.analytics.FirebaseAnalytics;
import com.google.firebase.appindexing.Action;
import com.google.firebase.appindexing.FirebaseAppIndex;
import com.google.firebase.appindexing.FirebaseUserActions;
import com.google.firebase.appindexing.Indexable;
import com.google.firebase.appindexing.builders.Actions;
import com.google.firebase.appindexing.builders.Indexables;
import com.google.firebase.appindexing.builders.PersonBuilder;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.auth.FirebaseUser;
import com.google.firebase.crash.FirebaseCrash;
import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.remoteconfig.FirebaseRemoteConfig;
import com.google.firebase.remoteconfig.FirebaseRemoteConfigSettings;
import com.google.firebase.storage.FirebaseStorage;
import com.google.firebase.storage.StorageReference;
import com.google.firebase.storage.UploadTask;
import java.util.HashMap;
import java.util.Map;
import de.hdodenhof.circleimageview.CircleImageView;
import android.provider.ContactsContract;
import android.support.v4.app.Fragment;
import android.support.v4.app.LoaderManager.LoaderCallbacks;
import android.widget.AdapterView;
public class MainActivity extends AppCompatActivity implements
GoogleApiClient.OnConnectionFailedListener {
/*
* Defines an array that contains column names to move from
* the Cursor to the ListView.
*/
/*
* Defines an array that contains column names to move from
* the Cursor to the ListView.
*/
@SuppressLint("InlinedApi")
private final static String[] FROM_COLUMNS = {
Build.VERSION.SDK_INT
>= Build.VERSION_CODES.HONEYCOMB ?
ContactsContract.Contacts.DISPLAY_NAME_PRIMARY :
ContactsContract.Contacts.DISPLAY_NAME
};
/*
* Defines an array that contains resource ids for the layout views
* that get the Cursor column contents. The id is pre-defined in
* the Android framework, so it is prefaced with "android.R.id"
*/
private final static int[] TO_IDS = {
android.R.id.text1
};
// Define global mutable variables
// Define a ListView object
ListView mContactsList;
// Define variables for the contact the user selects
// The contact's _ID value
long mContactId;
// The contact's LOOKUP_KEY
String mContactKey;
// A content URI for the selected contact
Uri mContactUri;
// An adapter that binds the result Cursor to the ListView
private SimpleCursorAdapter mCursorAdapter;
// Empty public constructor, required by the system
public ContactsFragment() {}
// A UI Fragment must inflate its View
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the fragment layout
return inflater.inflate(R.layout.contact_list_fragment,
container, false);
}
class ContactsFragment extends Fragment implements
LoaderManager.LoaderCallbacks<Cursor>,
AdapterView.OnItemClickListener {
@Override
public Loader<Cursor> onCreateLoader(int id, Bundle args) {
return null;
}
@Override
public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
}
@Override
public void onLoaderReset(Loader<Cursor> loader) {
}
/**
* Callback method to be invoked when an item in this AdapterView has
* been clicked.
* <p>
* Implementers can call getItemAtPosition(position) if they need
* to access the data associated with the selected item.
*
* @param parent The AdapterView where the click happened.
* @param view The view within the AdapterView that was clicked (this
* will be a view provided by the adapter)
* @param position The position of the view in the adapter.
* @param id The row id of the item that was clicked.
*/
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
}
}
/**
* ATTENTION: This was auto-generated to implement the App Indexing API.
* See https://g.co/AppIndexing/AndroidStudio for more information.
*/
public Action getIndexApiAction() {
return Actions.newView("Main", "http://friendlychat.firebase.google.com/message");
}
@Override
public void onStart() {
super.onStart();
// ATTENTION: This was auto-generated to implement the App Indexing API.
// See https://g.co/AppIndexing/AndroidStudio for more information.
FirebaseUserActions.getInstance().start(getIndexApiAction());
}
@Override
public void onStop() {
// ATTENTION: This was auto-generated to implement the App Indexing API.
// See https://g.co/AppIndexing/AndroidStudio for more information.
FirebaseUserActions.getInstance().end(getIndexApiAction());
super.onStop();
}
public static class MessageViewHolder extends RecyclerView.ViewHolder {
public TextView messageTextView;
public ImageView messageImageView;
public TextView messengerTextView;
public CircleImageView messengerImageView;
public MessageViewHolder(View v) {
super(v);
messageTextView = (TextView) itemView.findViewById(R.id.messageTextView);
messageImageView = (ImageView) itemView.findViewById(R.id.messageImageView);
messengerTextView = (TextView) itemView.findViewById(R.id.messengerTextView);
messengerImageView = (CircleImageView) itemView.findViewById(R.id.messengerImageView);
}
}
private static final String TAG = "MainActivity";
public static final String MESSAGES_CHILD = "messages";
private static final int REQUEST_INVITE = 1;
private static final int REQUEST_IMAGE = 2;
public static final int DEFAULT_MSG_LENGTH_LIMIT = 10;
public static final String ANONYMOUS = "anonymous";
private static final String MESSAGE_SENT_EVENT = "message_sent";
private static final String MESSAGE_URL = "http://friendlychat.firebase.google.com/message/";
private static final String LOADING_IMAGE_URL = "https://www.google.com/images/spin-32.gif";
private String mUsername;
private String mPhotoUrl;
private SharedPreferences mSharedPreferences;
private Button mSendButton;
private RecyclerView mMessageRecyclerView;
private LinearLayoutManager mLinearLayoutManager;
private FirebaseRecyclerAdapter<FriendlyMessage, MessageViewHolder> mFirebaseAdapter;
private ProgressBar mProgressBar;
private DatabaseReference mFirebaseDatabaseReference;
private FirebaseAuth mFirebaseAuth;
private FirebaseUser mFirebaseUser;
private FirebaseAnalytics mFirebaseAnalytics;
private EditText mMessageEditText;
private ImageView mAddMessageImageView;
private AdView mAdView;
private FirebaseRemoteConfig mFirebaseRemoteConfig;
private GoogleApiClient mGoogleApiClient;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mSharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
mUsername = ANONYMOUS;
// Initialize Firebase Auth
mFirebaseAuth = FirebaseAuth.getInstance();
mFirebaseUser = mFirebaseAuth.getCurrentUser();
if (mFirebaseUser == null) {
// Not signed in, launch the Sign In activity
startActivity(new Intent(this, SignInActivity.class));
finish();
return;
} else {
mUsername = mFirebaseUser.getDisplayName();
mPhotoUrl = mFirebaseUser.getPhotoUrl().toString();
}
mGoogleApiClient = new GoogleApiClient.Builder(this)
.enableAutoManage(this /* FragmentActivity */, this /* OnConnectionFailedListener */)
.addApi(Auth.GOOGLE_SIGN_IN_API)
.build();
mProgressBar = (ProgressBar) findViewById(R.id.progressBar);
mMessageRecyclerView = (RecyclerView) findViewById(R.id.messageRecyclerView);
mLinearLayoutManager = new LinearLayoutManager(this);
mLinearLayoutManager.setStackFromEnd(true);
mFirebaseDatabaseReference = FirebaseDatabase.getInstance().getReference();
mFirebaseAdapter = new FirebaseRecyclerAdapter<FriendlyMessage, MessageViewHolder>(
FriendlyMessage.class,
R.layout.item_message,
MessageViewHolder.class,
mFirebaseDatabaseReference.child(MESSAGES_CHILD)) {
@Override
protected FriendlyMessage parseSnapshot(DataSnapshot snapshot) {
FriendlyMessage friendlyMessage = super.parseSnapshot(snapshot);
if (friendlyMessage != null) {
friendlyMessage.setId(snapshot.getKey());
}
return friendlyMessage;
}
@Override
protected void populateViewHolder(final MessageViewHolder viewHolder,
FriendlyMessage friendlyMessage, int position) {
mProgressBar.setVisibility(ProgressBar.INVISIBLE);
if (friendlyMessage.getText() != null) {
viewHolder.messageTextView.setText(friendlyMessage.getText());
viewHolder.messageTextView.setVisibility(TextView.VISIBLE);
viewHolder.messageImageView.setVisibility(ImageView.GONE);
} else {
String imageUrl = friendlyMessage.getImageUrl();
if (imageUrl.startsWith("gs://")) {
StorageReference storageReference = FirebaseStorage.getInstance()
.getReferenceFromUrl(imageUrl);
storageReference.getDownloadUrl().addOnCompleteListener(
new OnCompleteListener<Uri>() {
@Override
public void onComplete(@NonNull Task<Uri> task) {
if (task.isSuccessful()) {
String downloadUrl = task.getResult().toString();
Glide.with(viewHolder.messageImageView.getContext())
.load(downloadUrl)
.into(viewHolder.messageImageView);
} else {
Log.w(TAG, "Getting download url was not successful.",
task.getException());
}
}
});
} else {
Glide.with(viewHolder.messageImageView.getContext())
.load(friendlyMessage.getImageUrl())
.into(viewHolder.messageImageView);
}
viewHolder.messageImageView.setVisibility(ImageView.VISIBLE);
viewHolder.messageTextView.setVisibility(TextView.GONE);
}
viewHolder.messengerTextView.setText(friendlyMessage.getName());
if (friendlyMessage.getPhotoUrl() == null) {
viewHolder.messengerImageView.setImageDrawable(ContextCompat.getDrawable(MainActivity.this,
R.drawable.ic_account_circle_black_36dp));
} else {
Glide.with(MainActivity.this)
.load(friendlyMessage.getPhotoUrl())
.into(viewHolder.messengerImageView);
}
if (friendlyMessage.getText() != null) {
// write this message to the on-device index
FirebaseAppIndex.getInstance().update(getMessageIndexable(friendlyMessage));
}
// log a view action on it
FirebaseUserActions.getInstance().end(getMessageViewAction(friendlyMessage));
}
};
mFirebaseAdapter.registerAdapterDataObserver(new RecyclerView.AdapterDataObserver() {
@Override
public void onItemRangeInserted(int positionStart, int itemCount) {
super.onItemRangeInserted(positionStart, itemCount);
int friendlyMessageCount = mFirebaseAdapter.getItemCount();
int lastVisiblePosition = mLinearLayoutManager.findLastCompletelyVisibleItemPosition();
// If the recycler view is initially being loaded or the user is at the bottom of the list, scroll
// to the bottom of the list to show the newly added message.
if (lastVisiblePosition == -1 ||
(positionStart >= (friendlyMessageCount - 1) && lastVisiblePosition == (positionStart - 1))) {
mMessageRecyclerView.scrollToPosition(positionStart);
}
}
});
mMessageRecyclerView.setLayoutManager(mLinearLayoutManager);
mMessageRecyclerView.setAdapter(mFirebaseAdapter);
// Initialize and request AdMob ad.
mAdView = (AdView) findViewById(R.id.adView);
AdRequest adRequest = new AdRequest.Builder().build();
mAdView.loadAd(adRequest);
// Initialize Firebase Measurement.
mFirebaseAnalytics = FirebaseAnalytics.getInstance(this);
// Initialize Firebase Remote Config.
mFirebaseRemoteConfig = FirebaseRemoteConfig.getInstance();
// Define Firebase Remote Config Settings.
FirebaseRemoteConfigSettings firebaseRemoteConfigSettings =
new FirebaseRemoteConfigSettings.Builder()
.setDeveloperModeEnabled(true)
.build();
// Define default config values. Defaults are used when fetched config values are not
// available. Eg: if an error occurred fetching values from the server.
Map<String, Object> defaultConfigMap = new HashMap<>();
defaultConfigMap.put("friendly_msg_length", 10L);
// Apply config settings and default values.
mFirebaseRemoteConfig.setConfigSettings(firebaseRemoteConfigSettings);
mFirebaseRemoteConfig.setDefaults(defaultConfigMap);
// Fetch remote config.
fetchConfig();
mMessageEditText = (EditText) findViewById(R.id.messageEditText);
mMessageEditText.setFilters(new InputFilter[]{new InputFilter.LengthFilter(mSharedPreferences
.getInt(CodelabPreferences.FRIENDLY_MSG_LENGTH, DEFAULT_MSG_LENGTH_LIMIT))});
mMessageEditText.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
if (charSequence.toString().trim().length() > 0) {
mSendButton.setEnabled(true);
} else {
mSendButton.setEnabled(false);
}
}
@Override
public void afterTextChanged(Editable editable) {
}
});
mAddMessageImageView = (ImageView) findViewById(R.id.addMessageImageView);
mAddMessageImageView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
intent.addCategory(Intent.CATEGORY_OPENABLE);
intent.setType("image/*");
startActivityForResult(intent, REQUEST_IMAGE);
}
});
mSendButton = (Button) findViewById(R.id.sendButton);
mSendButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
FriendlyMessage friendlyMessage = new FriendlyMessage(mMessageEditText.getText().toString(), mUsername,
mPhotoUrl, null);
mFirebaseDatabaseReference.child(MESSAGES_CHILD).push().setValue(friendlyMessage);
mMessageEditText.setText("");
mFirebaseAnalytics.logEvent(MESSAGE_SENT_EVENT, null);
}
});
}
private Action getMessageViewAction(FriendlyMessage friendlyMessage) {
return new Action.Builder(Action.Builder.VIEW_ACTION)
.setObject(friendlyMessage.getName(), MESSAGE_URL.concat(friendlyMessage.getId()))
.setMetadata(new Action.Metadata.Builder().setUpload(false))
.build();
}
}
package com.google.firebase.codelab.friendlychat；
导入android.annotation.SuppressLint；
导入android.content.Context；
导入android.content.CursorLoader；
导入android.content.Intent；
导入android.content.SharedReferences；
导入android.database.Cursor；
导入android.net.Uri；
导入android.os.Build；
导入android.os.Bundle；
导入android.preference.PreferenceManager；
导入android.support.annotation.NonNull；
导入android.support.v4.app.LoaderManager；
导入android.support.v4.content.ContextCompat；
导入android.support.v4.content.Loader；
导入android.support.v4.widget.SimpleCursorAdapter；
导入android.support.v7.app.AppActivity；
导入android.support.v7.widget.LinearLayoutManager；
导入android.support.v7.widget.RecyclerView；
导入android.text.Editable；
导入android.text.InputFilter；
导入android.text.TextWatcher；
导入android.util.Log；
导入android.view.LayoutInflater；
导入android.view.Menu；
导入android.view.MenuInflater；
导入android.view.MenuItem；
导入android.view.view；
导入android.view.ViewGroup；
导入android.widget.Button；
导入android.widget.CursorAdapter；
导入android.widget.EditText；
导入android.widget.ImageView；
导入android.widget.ListView；
导入android.widget.ProgressBar；
导入android.widget.TextView；
导入com.bumptech.glide.glide；
导入com.firebase.ui.database.FirebaseRecyclerAdapter；
导入com.google.android.gms.ads.AdRequest；
导入com.google.android.gms.ads.AdView；
导入com.google.android.gms.appinvite.appinvite邀请；
导入com.google.android.gms.auth.api.auth；
导入com.google.android.gms.common.ConnectionResult；
导入com.google.android.gms.common.api.GoogleAppClient；
导入com.google.android.gms.tasks.OnCompleteListener；
导入com.google.android.gms.tasks.OnFailureListener；
导入com.google.android.gms.tasks.OnSuccessListener；
导入com.google.android.gms.tasks.Task；
导入com.google.firebase.analytics.firebase分析；
导入com.google.firebase.appindexing.Action；
导入com.google.firebase.appindexing.FirebaseAppIndex；
导入com.google.firebase.appindexing.FirebaseUserActions；
导入com.google.firebase.appindexing.Indexable；
导入com.google.firebase.appindexing.builders.Actions；
导入com.google.firebase.appindexing.builders.Indexables；
导入com.google.firebase.appindexing.builders.PersonBuilder；
导入com.google.firebase.auth.FirebaseAuth；
导入com.google.firebase.auth.FirebaseUser；
导入com.google.firebase.crash.firebasecash；
导入com.google.firebase.database.DataSnapshot；
导入com.google.firebase.database.DatabaseError；
导入com.google.firebase.database.DatabaseReference；
导入com.google.firebase.database.FirebaseDatabase；
导入com.google.firebase.remoteconfig.firebasemoteconfig；
导入com.google.firebase.remoteconfig.FirebaseRemoteConfigSettings；
导入com.google.firebase.storage.firebase存储；
导入com.google.firebase.storage.StorageReference；
导入com.google.firebase.storage.UploadTask；
导入java.util.HashMap；
导入java.util.Map；
导入de.hdodenhof.circleimageview.circleimageview；
导入android.provider.contacts合同；
导入android.support.v4.app.Fragment；
导入android.support.v4.app.LoaderManager.LoaderCallbacks；
导入android.widget.AdapterView；
公共类MainActivity扩展了AppCompatActivity实现
GoogleAppClient.OnConnectionFailedListener{
/*
*定义包含要从中移动的列名的数组
*将光标移动到ListView。
*/
/*
*定义包含要从中移动的列名的数组
*将光标移动到ListView。
*/
@SuppressLint（“InlinedApi”）
_列中的私有最终静态字符串[]={
Build.VERSION.SDK_INT
>=Build.VERSION\u CODES.HONEYCOMB？
Contacts contract.Contacts.DISPLAY\u NAME\u PRIMARY：
Contacts contract.Contacts.DISPLAY\u NAME
};
/*
*定义包含布局视图的资源ID的数组
*获取游标列内容的。id在中预定义
*A
package com.google.firebase.codelab.friendlychat;
import android.annotation.SuppressLint;
import android.content.Context;
import android.content.CursorLoader;
import android.content.Intent;
import android.content.SharedPreferences;
import android.database.Cursor;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.preference.PreferenceManager;
import android.support.annotation.NonNull;
import android.support.v4.app.LoaderManager;
import android.support.v4.content.ContextCompat;
import android.support.v4.content.Loader;
import android.support.v4.widget.SimpleCursorAdapter;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.text.Editable;
import android.text.InputFilter;
import android.text.TextWatcher;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.CursorAdapter;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.ProgressBar;
import android.widget.TextView;
import com.bumptech.glide.Glide;
import com.firebase.ui.database.FirebaseRecyclerAdapter;
import com.google.android.gms.ads.AdRequest;
import com.google.android.gms.ads.AdView;
import com.google.android.gms.appinvite.AppInviteInvitation;
import com.google.android.gms.auth.api.Auth;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.OnFailureListener;
import com.google.android.gms.tasks.OnSuccessListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.analytics.FirebaseAnalytics;
import com.google.firebase.appindexing.Action;
import com.google.firebase.appindexing.FirebaseAppIndex;
import com.google.firebase.appindexing.FirebaseUserActions;
import com.google.firebase.appindexing.Indexable;
import com.google.firebase.appindexing.builders.Actions;
import com.google.firebase.appindexing.builders.Indexables;
import com.google.firebase.appindexing.builders.PersonBuilder;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.auth.FirebaseUser;
import com.google.firebase.crash.FirebaseCrash;
import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.remoteconfig.FirebaseRemoteConfig;
import com.google.firebase.remoteconfig.FirebaseRemoteConfigSettings;
import com.google.firebase.storage.FirebaseStorage;
import com.google.firebase.storage.StorageReference;
import com.google.firebase.storage.UploadTask;
import java.util.HashMap;
import java.util.Map;
import de.hdodenhof.circleimageview.CircleImageView;
import android.provider.ContactsContract;
import android.support.v4.app.Fragment;
import android.support.v4.app.LoaderManager.LoaderCallbacks;
import android.widget.AdapterView;
public class MainActivity extends AppCompatActivity implements
GoogleApiClient.OnConnectionFailedListener {
/*
* Defines an array that contains column names to move from
* the Cursor to the ListView.
*/
/*
* Defines an array that contains column names to move from
* the Cursor to the ListView.
*/
@SuppressLint("InlinedApi")
private final static String[] FROM_COLUMNS = {
Build.VERSION.SDK_INT
>= Build.VERSION_CODES.HONEYCOMB ?
ContactsContract.Contacts.DISPLAY_NAME_PRIMARY :
ContactsContract.Contacts.DISPLAY_NAME
};
/*
* Defines an array that contains resource ids for the layout views
* that get the Cursor column contents. The id is pre-defined in
* the Android framework, so it is prefaced with "android.R.id"
*/
private final static int[] TO_IDS = {
android.R.id.text1
};
// Define global mutable variables
// Define a ListView object
ListView mContactsList;
// Define variables for the contact the user selects
// The contact's _ID value
long mContactId;
// The contact's LOOKUP_KEY
String mContactKey;
// A content URI for the selected contact
Uri mContactUri;
// An adapter that binds the result Cursor to the ListView
private SimpleCursorAdapter mCursorAdapter;
// Empty public constructor, required by the system
public ContactsFragment() {}
// A UI Fragment must inflate its View
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the fragment layout
return inflater.inflate(R.layout.contact_list_fragment,
container, false);
}
class ContactsFragment extends Fragment implements
LoaderManager.LoaderCallbacks<Cursor>,
AdapterView.OnItemClickListener {
@Override
public Loader<Cursor> onCreateLoader(int id, Bundle args) {
return null;
}
@Override
public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
}
@Override
public void onLoaderReset(Loader<Cursor> loader) {
}
/**
* Callback method to be invoked when an item in this AdapterView has
* been clicked.
* <p>
* Implementers can call getItemAtPosition(position) if they need
* to access the data associated with the selected item.
*
* @param parent The AdapterView where the click happened.
* @param view The view within the AdapterView that was clicked (this
* will be a view provided by the adapter)
* @param position The position of the view in the adapter.
* @param id The row id of the item that was clicked.
*/
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
}
}
/**
* ATTENTION: This was auto-generated to implement the App Indexing API.
* See https://g.co/AppIndexing/AndroidStudio for more information.
*/
public Action getIndexApiAction() {
return Actions.newView("Main", "http://friendlychat.firebase.google.com/message");
}
@Override
public void onStart() {
super.onStart();
// ATTENTION: This was auto-generated to implement the App Indexing API.
// See https://g.co/AppIndexing/AndroidStudio for more information.
FirebaseUserActions.getInstance().start(getIndexApiAction());
}
@Override
public void onStop() {
// ATTENTION: This was auto-generated to implement the App Indexing API.
// See https://g.co/AppIndexing/AndroidStudio for more information.
FirebaseUserActions.getInstance().end(getIndexApiAction());
super.onStop();
}
public static class MessageViewHolder extends RecyclerView.ViewHolder {
public TextView messageTextView;
public ImageView messageImageView;
public TextView messengerTextView;
public CircleImageView messengerImageView;
public MessageViewHolder(View v) {
super(v);
messageTextView = (TextView) itemView.findViewById(R.id.messageTextView);
messageImageView = (ImageView) itemView.findViewById(R.id.messageImageView);
messengerTextView = (TextView) itemView.findViewById(R.id.messengerTextView);
messengerImageView = (CircleImageView) itemView.findViewById(R.id.messengerImageView);
}
}
private static final String TAG = "MainActivity";
public static final String MESSAGES_CHILD = "messages";
private static final int REQUEST_INVITE = 1;
private static final int REQUEST_IMAGE = 2;
public static final int DEFAULT_MSG_LENGTH_LIMIT = 10;
public static final String ANONYMOUS = "anonymous";
private static final String MESSAGE_SENT_EVENT = "message_sent";
private static final String MESSAGE_URL = "http://friendlychat.firebase.google.com/message/";
private static final String LOADING_IMAGE_URL = "https://www.google.com/images/spin-32.gif";
private String mUsername;
private String mPhotoUrl;
private SharedPreferences mSharedPreferences;
private Button mSendButton;
private RecyclerView mMessageRecyclerView;
private LinearLayoutManager mLinearLayoutManager;
private FirebaseRecyclerAdapter<FriendlyMessage, MessageViewHolder> mFirebaseAdapter;
private ProgressBar mProgressBar;
private DatabaseReference mFirebaseDatabaseReference;
private FirebaseAuth mFirebaseAuth;
private FirebaseUser mFirebaseUser;
private FirebaseAnalytics mFirebaseAnalytics;
private EditText mMessageEditText;
private ImageView mAddMessageImageView;
private AdView mAdView;
private FirebaseRemoteConfig mFirebaseRemoteConfig;
private GoogleApiClient mGoogleApiClient;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mSharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
mUsername = ANONYMOUS;
// Initialize Firebase Auth
mFirebaseAuth = FirebaseAuth.getInstance();
mFirebaseUser = mFirebaseAuth.getCurrentUser();
if (mFirebaseUser == null) {
// Not signed in, launch the Sign In activity
startActivity(new Intent(this, SignInActivity.class));
finish();
return;
} else {
mUsername = mFirebaseUser.getDisplayName();
mPhotoUrl = mFirebaseUser.getPhotoUrl().toString();
}
mGoogleApiClient = new GoogleApiClient.Builder(this)
.enableAutoManage(this /* FragmentActivity */, this /* OnConnectionFailedListener */)
.addApi(Auth.GOOGLE_SIGN_IN_API)
.build();
mProgressBar = (ProgressBar) findViewById(R.id.progressBar);
mMessageRecyclerView = (RecyclerView) findViewById(R.id.messageRecyclerView);
mLinearLayoutManager = new LinearLayoutManager(this);
mLinearLayoutManager.setStackFromEnd(true);
mFirebaseDatabaseReference = FirebaseDatabase.getInstance().getReference();
mFirebaseAdapter = new FirebaseRecyclerAdapter<FriendlyMessage, MessageViewHolder>(
FriendlyMessage.class,
R.layout.item_message,
MessageViewHolder.class,
mFirebaseDatabaseReference.child(MESSAGES_CHILD)) {
@Override
protected FriendlyMessage parseSnapshot(DataSnapshot snapshot) {
FriendlyMessage friendlyMessage = super.parseSnapshot(snapshot);
if (friendlyMessage != null) {
friendlyMessage.setId(snapshot.getKey());
}
return friendlyMessage;
}
@Override
protected void populateViewHolder(final MessageViewHolder viewHolder,
FriendlyMessage friendlyMessage, int position) {
mProgressBar.setVisibility(ProgressBar.INVISIBLE);
if (friendlyMessage.getText() != null) {
viewHolder.messageTextView.setText(friendlyMessage.getText());
viewHolder.messageTextView.setVisibility(TextView.VISIBLE);
viewHolder.messageImageView.setVisibility(ImageView.GONE);
} else {
String imageUrl = friendlyMessage.getImageUrl();
if (imageUrl.startsWith("gs://")) {
StorageReference storageReference = FirebaseStorage.getInstance()
.getReferenceFromUrl(imageUrl);
storageReference.getDownloadUrl().addOnCompleteListener(
new OnCompleteListener<Uri>() {
@Override
public void onComplete(@NonNull Task<Uri> task) {
if (task.isSuccessful()) {
String downloadUrl = task.getResult().toString();
Glide.with(viewHolder.messageImageView.getContext())
.load(downloadUrl)
.into(viewHolder.messageImageView);
} else {
Log.w(TAG, "Getting download url was not successful.",
task.getException());
}
}
});
} else {
Glide.with(viewHolder.messageImageView.getContext())
.load(friendlyMessage.getImageUrl())
.into(viewHolder.messageImageView);
}
viewHolder.messageImageView.setVisibility(ImageView.VISIBLE);
viewHolder.messageTextView.setVisibility(TextView.GONE);
}
viewHolder.messengerTextView.setText(friendlyMessage.getName());
if (friendlyMessage.getPhotoUrl() == null) {
viewHolder.messengerImageView.setImageDrawable(ContextCompat.getDrawable(MainActivity.this,
R.drawable.ic_account_circle_black_36dp));
} else {
Glide.with(MainActivity.this)
.load(friendlyMessage.getPhotoUrl())
.into(viewHolder.messengerImageView);
}
if (friendlyMessage.getText() != null) {
// write this message to the on-device index
FirebaseAppIndex.getInstance().update(getMessageIndexable(friendlyMessage));
}
// log a view action on it
FirebaseUserActions.getInstance().end(getMessageViewAction(friendlyMessage));
}
};
mFirebaseAdapter.registerAdapterDataObserver(new RecyclerView.AdapterDataObserver() {
@Override
public void onItemRangeInserted(int positionStart, int itemCount) {
super.onItemRangeInserted(positionStart, itemCount);
int friendlyMessageCount = mFirebaseAdapter.getItemCount();
int lastVisiblePosition = mLinearLayoutManager.findLastCompletelyVisibleItemPosition();
// If the recycler view is initially being loaded or the user is at the bottom of the list, scroll
// to the bottom of the list to show the newly added message.
if (lastVisiblePosition == -1 ||
(positionStart >= (friendlyMessageCount - 1) && lastVisiblePosition == (positionStart - 1))) {
mMessageRecyclerView.scrollToPosition(positionStart);
}
}
});
mMessageRecyclerView.setLayoutManager(mLinearLayoutManager);
mMessageRecyclerView.setAdapter(mFirebaseAdapter);
// Initialize and request AdMob ad.
mAdView = (AdView) findViewById(R.id.adView);
AdRequest adRequest = new AdRequest.Builder().build();
mAdView.loadAd(adRequest);
// Initialize Firebase Measurement.
mFirebaseAnalytics = FirebaseAnalytics.getInstance(this);
// Initialize Firebase Remote Config.
mFirebaseRemoteConfig = FirebaseRemoteConfig.getInstance();
// Define Firebase Remote Config Settings.
FirebaseRemoteConfigSettings firebaseRemoteConfigSettings =
new FirebaseRemoteConfigSettings.Builder()
.setDeveloperModeEnabled(true)
.build();
// Define default config values. Defaults are used when fetched config values are not
// available. Eg: if an error occurred fetching values from the server.
Map<String, Object> defaultConfigMap = new HashMap<>();
defaultConfigMap.put("friendly_msg_length", 10L);
// Apply config settings and default values.
mFirebaseRemoteConfig.setConfigSettings(firebaseRemoteConfigSettings);
mFirebaseRemoteConfig.setDefaults(defaultConfigMap);
// Fetch remote config.
fetchConfig();
mMessageEditText = (EditText) findViewById(R.id.messageEditText);
mMessageEditText.setFilters(new InputFilter[]{new InputFilter.LengthFilter(mSharedPreferences
.getInt(CodelabPreferences.FRIENDLY_MSG_LENGTH, DEFAULT_MSG_LENGTH_LIMIT))});
mMessageEditText.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
if (charSequence.toString().trim().length() > 0) {
mSendButton.setEnabled(true);
} else {
mSendButton.setEnabled(false);
}
}
@Override
public void afterTextChanged(Editable editable) {
}
});
mAddMessageImageView = (ImageView) findViewById(R.id.addMessageImageView);
mAddMessageImageView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT);
intent.addCategory(Intent.CATEGORY_OPENABLE);
intent.setType("image/*");
startActivityForResult(intent, REQUEST_IMAGE);
}
});
mSendButton = (Button) findViewById(R.id.sendButton);
mSendButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
FriendlyMessage friendlyMessage = new FriendlyMessage(mMessageEditText.getText().toString(), mUsername,
mPhotoUrl, null);
mFirebaseDatabaseReference.child(MESSAGES_CHILD).push().setValue(friendlyMessage);
mMessageEditText.setText("");
mFirebaseAnalytics.logEvent(MESSAGE_SENT_EVENT, null);
}
});
}
private Action getMessageViewAction(FriendlyMessage friendlyMessage) {
return new Action.Builder(Action.Builder.VIEW_ACTION)
.setObject(friendlyMessage.getName(), MESSAGE_URL.concat(friendlyMessage.getId()))
.setMetadata(new Action.Metadata.Builder().setUpload(false))
.build();
}
}
public class MainActivity.java