我正在寻找与使用Android应用访问Google云端硬盘相关的一些指导。
1）我需要能够读取用户在我的应用之外上传的文件。这是否意味着我需要全驱动访问？ （如果应用程序可以创建一个文件夹，然后查看该文件夹中存在的用户上传的所有文件，那就太棒了，但我认为它不会这样。）
2）如果我需要全驱动访问权限，Googles“Drive API for Android”似乎不支持此功能，我需要使用REST api。我认为这是真的。
3）我需要来自Google的Auth 2.0客户端ID。如果我使用其余的API，这是否意味着我需要使用“Web应用程序”ID？我想我需要这个，因为我想要一个“授权代码”。我无法使用“Android”类型ID。
4）我目前正在使用Android的“Google登录”来处理登录并提供身份验证代码。然后我可以将它转换为令牌+刷新令牌，并保存这些，这样我可以在一小时后以某种方式获得新的令牌。是否需要手动处理刷新令牌？
它变得很难看，但我认为既然我需要（？）全驱动访问，那么这就是程序。
感谢任何指导。
编辑：该问题已被确定为重复。提供的链接为问题＃2提供了答案，但未解决其他问题。
我同意这个问题很混乱......
答案 0 :(得分：6)
我正在回答我自己的问题。
我为此苦苦挣扎，因为A）Google的REST示例使用过时的登录过程，B）“登录”示例使用的代码不适用于“完全访问”范围，而C）有太多尝试将它们放在一起时，代码示例大不相同。
快速回答我现在看到的问题： 1）是的，读取在我的应用程序外部上传的文件需要完全驱动器访问权限。 2）是的，我需要使用REST api。 3）是的，我需要一个“Web应用程序”客户端ID。 4）Google登录似乎是目前登录的最佳方式，只要您保留刷新令牌，使用GoogleCredential对象和Drive api abject就会自动处理令牌刷新。
如果其他人正在努力使用最新的“登录”程序和REST v3从Android访问完全访问权限，下面是我的示例代码。
除了“Web应用程序”OAuth客户端ID之外，您还需要创建具有匹配包名称和证书指纹的“Android”类型ID，以便登录工作。另请注意，您的开发和生产版本将拥有不同的证书。这些Android客户端的ID /代码无需输入到应用程序中。
build.gradle：app
// Google Sign In
compile 'com.google.android.gms:play-services-auth:10.0.1'
// Drive REST API
compile('com.google.apis:google-api-services-drive:v3-rev54-1.22.0') {
exclude group: 'org.apache.httpcomponents'
}
活动
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
// Callback from Signin (Auth.GoogleSignInApi.getSignInIntent)
if (requestCode == 1) {
GoogleSignInResult result = Auth.GoogleSignInApi.getSignInResultFromIntent(data);
_googleApi.handleSignInResult(result);
}
}
开展工作的“GoogleApi”课程
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.pm.ApplicationInfo;
import android.os.Bundle;
import android.os.Handler;
import android.util.Log;
import com.google.android.gms.auth.api.Auth;
import com.google.android.gms.auth.api.signin.GoogleSignInAccount;
import com.google.android.gms.auth.api.signin.GoogleSignInOptions;
import com.google.android.gms.auth.api.signin.GoogleSignInResult;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.common.api.ResultCallback;
import com.google.android.gms.common.api.Scope;
import com.google.android.gms.common.api.Status;
import com.google.api.client.googleapis.auth.oauth2.GoogleAuthorizationCodeTokenRequest;
import com.google.api.client.googleapis.auth.oauth2.GoogleCredential;
import com.google.api.client.googleapis.auth.oauth2.GoogleTokenResponse;
import com.google.api.client.http.HttpTransport;
import com.google.api.client.http.javanet.NetHttpTransport;
import com.google.api.client.json.JsonFactory;
import com.google.api.client.json.jackson2.JacksonFactory;
import com.google.api.services.drive.Drive;
import com.google.api.services.drive.model.File;
import com.google.api.services.drive.model.FileList;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Locale;
public class GoogleApi implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener {
private Context _context;
private Handler _handler;
private GoogleCredential _credential;
private Drive _drive;
private GoogleApiClient _googleApiClient; // only set during login process
private Activity _activity; // launch intent for login (UI)
// Saved to data store
private boolean _loggedIn;
private String _refreshToken; // store, even if user is logged out as we may need to reuse
private static final String ClientID = "xxxxxx.apps.googleusercontent.com"; // web client
private static final String ClientSecret = "xxxxx"; // web client
private class FileAndErrorMsg {
public File file;
public String errorMsg;
public FileAndErrorMsg (File file_, String errorMsg_) { file = file_; errorMsg = errorMsg_; }
}
private class FileListAndErrorMsg {
public List<File> fileList;
public String errorMsg;
public FileListAndErrorMsg (List<File> fileList_, String errorMsg_) { fileList = fileList_; errorMsg = errorMsg_; }
}
// -------------------
// Constructor
// -------------------
public GoogleApi (Context context) {
_context = context;
_handler = new Handler();
loadFromPrefs(); // loggedIn, refreshToken
// create credential; will refresh itself automatically (in Drive calls) as long as valid refresh token exists
HttpTransport transport = new NetHttpTransport();
JsonFactory jsonFactory = JacksonFactory.getDefaultInstance();
_credential = new GoogleCredential.Builder()
.setTransport(transport)
.setJsonFactory(jsonFactory)
.setClientSecrets(ClientID, ClientSecret) // .addRefreshListener
.build();
_credential.setRefreshToken(_refreshToken);
// Get app name from Manifest (for Drive builder)
ApplicationInfo appInfo = context.getApplicationInfo();
String appName = appInfo.labelRes == 0 ? appInfo.nonLocalizedLabel.toString() : context.getString(appInfo.labelRes);
_drive = new Drive.Builder(transport, jsonFactory, _credential).setApplicationName(appName).build();
}
// -------------------
// Auth
// -------------------
// https://developers.google.com/identity/sign-in/android/offline-access#before_you_begin
// https://developers.google.com/identity/sign-in/android/offline-access#enable_server-side_api_access_for_your_app
// https://android-developers.googleblog.com/2016/02/using-credentials-between-your-server.html
// https://android-developers.googleblog.com/2016/05/improving-security-and-user-experience.html
public boolean isLoggedIn () {
return _loggedIn;
}
public void startAuth(Activity activity) {
startAuth(activity, false);
}
public void startAuth(Activity activity, boolean forceRefreshToken) {
_activity = activity;
_loggedIn = false;
saveToPrefs();
GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
.requestScopes(new Scope("https://www.googleapis.com/auth/drive"))
.requestServerAuthCode(ClientID, forceRefreshToken) // if force, guaranteed to get back refresh token, but will show "offline access?" if Google already issued refresh token
.build();
_googleApiClient = new GoogleApiClient.Builder(activity)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(Auth.GOOGLE_SIGN_IN_API, gso)
.build();
_googleApiClient.connect();
}
@Override
public void onConnected(Bundle connectionHint) {
// Called soon after .connect()
// This is only called when starting our Login process. Sign Out first so select-account screen shown. (OK if not already signed in)
Auth.GoogleSignInApi.signOut(_googleApiClient).setResultCallback(new ResultCallback<Status>() {
@Override
public void onResult(Status status) {
// Start sign in
Intent signInIntent = Auth.GoogleSignInApi.getSignInIntent(_googleApiClient);
_activity.startActivityForResult(signInIntent, 1); // Activity's onActivityResult will use the same code: 1
}
});
}
@Override
public void onConnectionSuspended(int cause) {
authDone("Connection suspended.");
}
@Override
public void onConnectionFailed(ConnectionResult connectionResult) { authDone("Connection failed."); }
public void handleSignInResult(GoogleSignInResult result) {
// Callback from Activity > onActivityResult
if (result.isSuccess()) {
GoogleSignInAccount acct = result.getSignInAccount();
String authCode = acct.getServerAuthCode();
new Thread(new ContinueAuthWithAuthCode_Background(authCode)).start();
}
else authDone("Login canceled or unable to connect to Google."); // can we get better error message?
}
private class ContinueAuthWithAuthCode_Background implements Runnable {
String _authCode;
public ContinueAuthWithAuthCode_Background (String authCode) {
_authCode = authCode;
}
public void run() {
// Convert authCode to tokens
GoogleTokenResponse tokenResponse = null;
String errorMsg = null;
try {
tokenResponse = new GoogleAuthorizationCodeTokenRequest(new NetHttpTransport(), JacksonFactory.getDefaultInstance(), "https://www.googleapis.com/oauth2/v4/token", ClientID, ClientSecret, _authCode, "").execute();
}
catch (IOException e) { errorMsg = e.getLocalizedMessage(); }
final GoogleTokenResponse tokenResponseFinal = tokenResponse;
final String errorMsgFinal = errorMsg;
_handler.post(new Runnable() { public void run() {
// Main thread
GoogleTokenResponse tokenResponse = tokenResponseFinal;
String errorMsg = errorMsgFinal;
if (tokenResponse != null && errorMsg == null) {
_credential.setFromTokenResponse(tokenResponse); // this will keep old refresh token if no new one sent
_refreshToken = _credential.getRefreshToken();
_loggedIn = true;
saveToPrefs();
// FIXME: if our refresh token is bad and we're not getting a new one, how do we deal with this?
Log("New refresh token: " + tokenResponse.getRefreshToken());
}
else if (errorMsg == null) errorMsg = "Get token error."; // shouldn't get here
authDone(errorMsg);
} });
}
}
private void authDone(String errorMsg) {
// Disconnect (we only need googleApiClient for login process)
if (_googleApiClient != null && _googleApiClient.isConnected()) _googleApiClient.disconnect();
_googleApiClient = null;
}
/*
public void signOut() {
Auth.GoogleSignInApi.signOut(_googleApiClient).setResultCallback(new ResultCallback<Status>() {
@Override
public void onResult(Status status) {
}
});
}
public void revokeAccess() {
// FIXME: I don't know yet, but this may revoke access for all android devices
Auth.GoogleSignInApi.revokeAccess(_googleApiClient).setResultCallback(new ResultCallback<Status>() {
@Override
public void onResult(Status status) {
}
});
}
*/
public void LogOut() {
_loggedIn = false;
saveToPrefs(); // don't clear refresh token as we may need again
}
// -------------------
// API Calls
// -------------------
public void makeApiCall() {
new Thread(new TestApiCall_Background()).start();
}
private class TestApiCall_Background implements Runnable {
public void run() {
FileAndErrorMsg fileAndErr = getFolderFromName_b("Many Files", null);
if (fileAndErr.errorMsg != null) Log("getFolderFromName_b error: " + fileAndErr.errorMsg);
else {
FileListAndErrorMsg fileListAndErr = getFileListInFolder_b(fileAndErr.file);
if (fileListAndErr.errorMsg != null)
Log("getFileListInFolder_b error: " + fileListAndErr.errorMsg);
else {
Log("file count: " + fileListAndErr.fileList.size());
for (File file : fileListAndErr.fileList) {
//Log(file.getName());
}
}
}
_handler.post(new Runnable() { public void run() {
// Main thread
} });
}
}
private FileAndErrorMsg getFolderFromName_b (String folderName, File parent) {
// parent can be null for top level
// Working with folders: https://developers.google.com/drive/v3/web/folder
File folder = null;
folderName = folderName.replace("'", "\\'"); // escape '
String q = String.format(Locale.US, "mimeType='application/vnd.google-apps.folder' and '%s' in parents and name='%s' and trashed=false", parent == null ? "root" : parent.getId(), folderName);
String errorMsg = null;
try {
FileList result = _drive.files().list().setQ(q).setPageSize(1000).execute();
int foundCount = 0;
for (File file : result.getFiles()) {
foundCount++;
folder = file;
}
if (foundCount == 0) errorMsg = "Folder not found: " + folderName;
else if (foundCount > 1) errorMsg = "More than one folder found with name (" + foundCount + "): " + folderName;
}
catch (IOException e) { errorMsg = e.getLocalizedMessage(); }
if (errorMsg != null) folder = null;
return new FileAndErrorMsg(folder, errorMsg);
}
private FileListAndErrorMsg getFileListInFolder_b (File folder) {
// folder can be null for top level; does not return subfolder names
List<File> fileList = new ArrayList<File>();
String q = String.format(Locale.US, "mimeType != 'application/vnd.google-apps.folder' and '%s' in parents and trashed=false", folder == null ? "root" : folder.getId());
String errorMsg = null;
try {
String pageToken = null;
do {
FileList result = _drive.files().list().setQ(q).setPageSize(1000).setPageToken(pageToken).execute();
fileList.addAll(result.getFiles());
pageToken = result.getNextPageToken();
} while (pageToken != null);
}
catch (IOException e) { errorMsg = e.getLocalizedMessage(); }
if (errorMsg != null) fileList = null;
return new FileListAndErrorMsg(fileList, errorMsg);
}
// -------------------
// Misc
// -------------------
private void Log(String msg) {
Log.v("ept", msg);
}
// -------------------
// Load/Save Tokens
// -------------------
private void loadFromPrefs() {
SharedPreferences pref = _context.getSharedPreferences("prefs", Context.MODE_PRIVATE);
_loggedIn = pref.getBoolean("GoogleLoggedIn", false);
_refreshToken = pref.getString("GoogleRefreshToken", null);
}
private void saveToPrefs() {
SharedPreferences.Editor editor = _context.getSharedPreferences("prefs", Context.MODE_PRIVATE).edit();
editor.putBoolean("GoogleLoggedIn", _loggedIn);
editor.putString("GoogleRefreshToken", _refreshToken);
editor.apply(); // async
}
}
答案 1 :(得分：0)
https://developers.google.com/drive/v3/web/quickstart/android中的最新示例开箱即用。
请执行以下操作：
1 - 转到Google API控制台，使用您的软件包名称和调试/发布密钥创建OAuth2客户端ID作为签名证书指纹。
2 - 启用Google云端硬盘API
3 - 应用以下代码
build.gradle：app
compile 'com.google.android.gms:play-services-auth:10.0.1'
compile 'pub.devrel:easypermissions:0.2.1'
compile('com.google.api-client:google-api-client-android:1.22.0') {
exclude group: 'org.apache.httpcomponents'
}
compile('com.google.apis:google-api-services-drive:v3-rev57-1.22.0') {
exclude group: 'org.apache.httpcomponents'
}
活动
在此代码中，只需将范围更改为DriveScopes.DRIVE即可获得完整的驱动器访问权限
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GoogleApiAvailability;
import com.google.api.client.extensions.android.http.AndroidHttp;
import com.google.api.client.googleapis.extensions.android.gms.auth.GoogleAccountCredential;
import com.google.api.client.googleapis.extensions.android.gms.auth.GooglePlayServicesAvailabilityIOException;
import com.google.api.client.googleapis.extensions.android.gms.auth.UserRecoverableAuthIOException;
import com.google.api.client.http.HttpTransport;
import com.google.api.client.json.JsonFactory;
import com.google.api.client.json.jackson2.JacksonFactory;
import com.google.api.client.util.ExponentialBackOff;
import com.google.api.services.drive.DriveScopes;
import com.google.api.services.drive.model.*;
import android.Manifest;
import android.accounts.AccountManager;
import android.app.Activity;
import android.app.Dialog;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.text.TextUtils;
import android.text.method.ScrollingMovementMethod;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.TextView;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import pub.devrel.easypermissions.AfterPermissionGranted;
import pub.devrel.easypermissions.EasyPermissions;
public class MainActivity extends Activity
implements EasyPermissions.PermissionCallbacks {
GoogleAccountCredential mCredential;
private TextView mOutputText;
private Button mCallApiButton;
ProgressDialog mProgress;
static final int REQUEST_ACCOUNT_PICKER = 1000;
static final int REQUEST_AUTHORIZATION = 1001;
static final int REQUEST_GOOGLE_PLAY_SERVICES = 1002;
static final int REQUEST_PERMISSION_GET_ACCOUNTS = 1003;
private static final String BUTTON_TEXT = "Call Drive API";
private static final String PREF_ACCOUNT_NAME = "accountName";
private static final String[] SCOPES = { DriveScopes.DRIVE };
/**
* Create the main activity.
* @param savedInstanceState previously saved instance data.
*/
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
LinearLayout activityLayout = new LinearLayout(this);
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.MATCH_PARENT,
LinearLayout.LayoutParams.MATCH_PARENT);
activityLayout.setLayoutParams(lp);
activityLayout.setOrientation(LinearLayout.VERTICAL);
activityLayout.setPadding(16, 16, 16, 16);
ViewGroup.LayoutParams tlp = new ViewGroup.LayoutParams(
ViewGroup.LayoutParams.WRAP_CONTENT,
ViewGroup.LayoutParams.WRAP_CONTENT);
mCallApiButton = new Button(this);
mCallApiButton.setText(BUTTON_TEXT);
mCallApiButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mCallApiButton.setEnabled(false);
mOutputText.setText("");
getResultsFromApi();
mCallApiButton.setEnabled(true);
}
});
activityLayout.addView(mCallApiButton);
mOutputText = new TextView(this);
mOutputText.setLayoutParams(tlp);
mOutputText.setPadding(16, 16, 16, 16);
mOutputText.setVerticalScrollBarEnabled(true);
mOutputText.setMovementMethod(new ScrollingMovementMethod());
mOutputText.setText(
"Click the \'" + BUTTON_TEXT +"\' button to test the API.");
activityLayout.addView(mOutputText);
mProgress = new ProgressDialog(this);
mProgress.setMessage("Calling Drive API ...");
setContentView(activityLayout);
// Initialize credentials and service object.
mCredential = GoogleAccountCredential.usingOAuth2(
getApplicationContext(), Arrays.asList(SCOPES))
.setBackOff(new ExponentialBackOff());
}
/**
* Attempt to call the API, after verifying that all the preconditions are
* satisfied. The preconditions are: Google Play Services installed, an
* account was selected and the device currently has online access. If any
* of the preconditions are not satisfied, the app will prompt the user as
* appropriate.
*/
private void getResultsFromApi() {
if (! isGooglePlayServicesAvailable()) {
acquireGooglePlayServices();
} else if (mCredential.getSelectedAccountName() == null) {
chooseAccount();
} else if (! isDeviceOnline()) {
mOutputText.setText("No network connection available.");
} else {
new MakeRequestTask(mCredential).execute();
}
}
/**
* Attempts to set the account used with the API credentials. If an account
* name was previously saved it will use that one; otherwise an account
* picker dialog will be shown to the user. Note that the setting the
* account to use with the credentials object requires the app to have the
* GET_ACCOUNTS permission, which is requested here if it is not already
* present. The AfterPermissionGranted annotation indicates that this
* function will be rerun automatically whenever the GET_ACCOUNTS permission
* is granted.
*/
@AfterPermissionGranted(REQUEST_PERMISSION_GET_ACCOUNTS)
private void chooseAccount() {
if (EasyPermissions.hasPermissions(
this, Manifest.permission.GET_ACCOUNTS)) {
String accountName = getPreferences(Context.MODE_PRIVATE)
.getString(PREF_ACCOUNT_NAME, null);
if (accountName != null) {
mCredential.setSelectedAccountName(accountName);
getResultsFromApi();
} else {
// Start a dialog from which the user can choose an account
startActivityForResult(
mCredential.newChooseAccountIntent(),
REQUEST_ACCOUNT_PICKER);
}
} else {
// Request the GET_ACCOUNTS permission via a user dialog
EasyPermissions.requestPermissions(
this,
"This app needs to access your Google account (via Contacts).",
REQUEST_PERMISSION_GET_ACCOUNTS,
Manifest.permission.GET_ACCOUNTS);
}
}
/**
* Called when an activity launched here (specifically, AccountPicker
* and authorization) exits, giving you the requestCode you started it with,
* the resultCode it returned, and any additional data from it.
* @param requestCode code indicating which activity result is incoming.
* @param resultCode code indicating the result of the incoming
* activity result.
* @param data Intent (containing result data) returned by incoming
* activity result.
*/
@Override
protected void onActivityResult(
int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
switch(requestCode) {
case REQUEST_GOOGLE_PLAY_SERVICES:
if (resultCode != RESULT_OK) {
mOutputText.setText(
"This app requires Google Play Services. Please install " +
"Google Play Services on your device and relaunch this app.");
} else {
getResultsFromApi();
}
break;
case REQUEST_ACCOUNT_PICKER:
if (resultCode == RESULT_OK && data != null &&
data.getExtras() != null) {
String accountName =
data.getStringExtra(AccountManager.KEY_ACCOUNT_NAME);
if (accountName != null) {
SharedPreferences settings =
getPreferences(Context.MODE_PRIVATE);
SharedPreferences.Editor editor = settings.edit();
editor.putString(PREF_ACCOUNT_NAME, accountName);
editor.apply();
mCredential.setSelectedAccountName(accountName);
getResultsFromApi();
}
}
break;
case REQUEST_AUTHORIZATION:
if (resultCode == RESULT_OK) {
getResultsFromApi();
}
break;
}
}
/**
* Respond to requests for permissions at runtime for API 23 and above.
* @param requestCode The request code passed in
* requestPermissions(android.app.Activity, String, int, String[])
* @param permissions The requested permissions. Never null.
* @param grantResults The grant results for the corresponding permissions
* which is either PERMISSION_GRANTED or PERMISSION_DENIED. Never null.
*/
@Override
public void onRequestPermissionsResult(int requestCode,
@NonNull String[] permissions,
@NonNull int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
EasyPermissions.onRequestPermissionsResult(
requestCode, permissions, grantResults, this);
}
/**
* Callback for when a permission is granted using the EasyPermissions
* library.
* @param requestCode The request code associated with the requested
* permission
* @param list The requested permission list. Never null.
*/
@Override
public void onPermissionsGranted(int requestCode, List<String> list) {
// Do nothing.
}
/**
* Callback for when a permission is denied using the EasyPermissions
* library.
* @param requestCode The request code associated with the requested
* permission
* @param list The requested permission list. Never null.
*/
@Override
public void onPermissionsDenied(int requestCode, List<String> list) {
// Do nothing.
}
/**
* Checks whether the device currently has a network connection.
* @return true if the device has a network connection, false otherwise.
*/
private boolean isDeviceOnline() {
ConnectivityManager connMgr =
(ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
return (networkInfo != null && networkInfo.isConnected());
}
/**
* Check that Google Play services APK is installed and up to date.
* @return true if Google Play Services is available and up to
* date on this device; false otherwise.
*/
private boolean isGooglePlayServicesAvailable() {
GoogleApiAvailability apiAvailability =
GoogleApiAvailability.getInstance();
final int connectionStatusCode =
apiAvailability.isGooglePlayServicesAvailable(this);
return connectionStatusCode == ConnectionResult.SUCCESS;
}
/**
* Attempt to resolve a missing, out-of-date, invalid or disabled Google
* Play Services installation via a user dialog, if possible.
*/
private void acquireGooglePlayServices() {
GoogleApiAvailability apiAvailability =
GoogleApiAvailability.getInstance();
final int connectionStatusCode =
apiAvailability.isGooglePlayServicesAvailable(this);
if (apiAvailability.isUserResolvableError(connectionStatusCode)) {
showGooglePlayServicesAvailabilityErrorDialog(connectionStatusCode);
}
}
/**
* Display an error dialog showing that Google Play Services is missing
* or out of date.
* @param connectionStatusCode code describing the presence (or lack of)
* Google Play Services on this device.
*/
void showGooglePlayServicesAvailabilityErrorDialog(
final int connectionStatusCode) {
GoogleApiAvailability apiAvailability = GoogleApiAvailability.getInstance();
Dialog dialog = apiAvailability.getErrorDialog(
MainActivity.this,
connectionStatusCode,
REQUEST_GOOGLE_PLAY_SERVICES);
dialog.show();
}
/**
* An asynchronous task that handles the Drive API call.
* Placing the API calls in their own task ensures the UI stays responsive.
*/
private class MakeRequestTask extends AsyncTask<Void, Void, List<String>> {
private com.google.api.services.drive.Drive mService = null;
private Exception mLastError = null;
MakeRequestTask(GoogleAccountCredential credential) {
HttpTransport transport = AndroidHttp.newCompatibleTransport();
JsonFactory jsonFactory = JacksonFactory.getDefaultInstance();
mService = new com.google.api.services.drive.Drive.Builder(
transport, jsonFactory, credential)
.setApplicationName("Drive API Android Quickstart")
.build();
}
/**
* Background task to call Drive API.
* @param params no parameters needed for this task.
*/
@Override
protected List<String> doInBackground(Void... params) {
try {
return getDataFromApi();
} catch (Exception e) {
mLastError = e;
cancel(true);
return null;
}
}
/**
* Fetch a list of up to 10 file names and IDs.
* @return List of Strings describing files, or an empty list if no files
* found.
* @throws IOException
*/
private List<String> getDataFromApi() throws IOException {
// Get a list of up to 10 files.
List<String> fileInfo = new ArrayList<String>();
FileList result = mService.files().list()
.setPageSize(10)
.setFields("nextPageToken, files(id, name)")
.execute();
List<File> files = result.getFiles();
if (files != null) {
for (File file : files) {
fileInfo.add(String.format("%s (%s)\n",
file.getName(), file.getId()));
}
}
return fileInfo;
}
@Override
protected void onPreExecute() {
mOutputText.setText("");
mProgress.show();
}
@Override
protected void onPostExecute(List<String> output) {
mProgress.hide();
if (output == null || output.size() == 0) {
mOutputText.setText("No results returned.");
} else {
output.add(0, "Data retrieved using the Drive API:");
mOutputText.setText(TextUtils.join("\n", output));
}
}
@Override
protected void onCancelled() {
mProgress.hide();
if (mLastError != null) {
if (mLastError instanceof GooglePlayServicesAvailabilityIOException) {
showGooglePlayServicesAvailabilityErrorDialog(
((GooglePlayServicesAvailabilityIOException) mLastError)
.getConnectionStatusCode());
} else if (mLastError instanceof UserRecoverableAuthIOException) {
startActivityForResult(
((UserRecoverableAuthIOException) mLastError).getIntent(),
MainActivity.REQUEST_AUTHORIZATION);
} else {
mOutputText.setText("The following error occurred:\n"
+ mLastError.getMessage());
}
} else {
mOutputText.setText("Request cancelled.");
}
}
}
}