Java tutorial
/* * Copyright (C) 2012-2018 Tobias Brunner * HSR Hochschule fuer Technik Rapperswil * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2 of the License, or (at your * option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * for more details. */ package org.strongswan.android.ui; import android.app.Dialog; import android.app.Service; import android.content.ActivityNotFoundException; import android.content.ComponentName; import android.content.DialogInterface; import android.content.Intent; import android.content.ServiceConnection; import android.net.VpnService; import android.os.Bundle; import android.os.IBinder; import android.support.v4.app.Fragment; import android.support.v4.app.FragmentManager; import android.support.v4.app.FragmentTransaction; import android.support.v7.app.AlertDialog; import android.support.v7.app.AppCompatActivity; import android.support.v7.app.AppCompatDialogFragment; import android.view.LayoutInflater; import android.view.View; import android.widget.EditText; import android.widget.Toast; import org.strongswan.android.R; import org.strongswan.android.data.VpnProfile; import org.strongswan.android.data.VpnProfileDataSource; import org.strongswan.android.data.VpnType.VpnTypeFeature; import org.strongswan.android.logic.VpnStateService; import org.strongswan.android.logic.VpnStateService.State; public class VpnProfileControlActivity extends AppCompatActivity { public static final String START_PROFILE = "org.strongswan.android.action.START_PROFILE"; public static final String DISCONNECT = "org.strongswan.android.action.DISCONNECT"; public static final String EXTRA_VPN_PROFILE_ID = "org.strongswan.android.VPN_PROFILE_ID"; private static final int PREPARE_VPN_SERVICE = 0; private static final String WAITING_FOR_RESULT = "WAITING_FOR_RESULT"; private static final String PROFILE_NAME = "PROFILE_NAME"; private static final String PROFILE_REQUIRES_PASSWORD = "REQUIRES_PASSWORD"; private static final String PROFILE_RECONNECT = "RECONNECT"; private static final String PROFILE_DISCONNECT = "DISCONNECT"; private static final String DIALOG_TAG = "Dialog"; private Bundle mProfileInfo; private boolean mWaitingForResult; private VpnStateService mService; private final ServiceConnection mServiceConnection = new ServiceConnection() { @Override public void onServiceDisconnected(ComponentName name) { mService = null; } @Override public void onServiceConnected(ComponentName name, IBinder service) { mService = ((VpnStateService.LocalBinder) service).getService(); handleIntent(); } }; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); if (savedInstanceState != null) { mWaitingForResult = savedInstanceState.getBoolean(WAITING_FOR_RESULT, false); } this.bindService(new Intent(this, VpnStateService.class), mServiceConnection, Service.BIND_AUTO_CREATE); } @Override protected void onSaveInstanceState(Bundle outState) { super.onSaveInstanceState(outState); outState.putBoolean(WAITING_FOR_RESULT, mWaitingForResult); } @Override protected void onDestroy() { super.onDestroy(); if (mService != null) { this.unbindService(mServiceConnection); } } /** * Due to launchMode=singleTop this is called if the Activity already exists */ @Override protected void onNewIntent(Intent intent) { super.onNewIntent(intent); /* store this intent in case the service is not yet connected or the activity is restarted */ setIntent(intent); if (mService != null) { handleIntent(); } } /** * Prepare the VpnService. If this succeeds the current VPN profile is * started. * * @param profileInfo a bundle containing the information about the profile to be started */ protected void prepareVpnService(Bundle profileInfo) { Intent intent; if (mWaitingForResult) { mProfileInfo = profileInfo; return; } try { intent = VpnService.prepare(this); } catch (IllegalStateException ex) { /* this happens if the always-on VPN feature (Android 4.2+) is activated */ VpnNotSupportedError.showWithMessage(this, R.string.vpn_not_supported_during_lockdown); return; } catch (NullPointerException ex) { /* not sure when this happens exactly, but apparently it does */ VpnNotSupportedError.showWithMessage(this, R.string.vpn_not_supported); return; } /* store profile info until the user grants us permission */ mProfileInfo = profileInfo; if (intent != null) { try { mWaitingForResult = true; startActivityForResult(intent, PREPARE_VPN_SERVICE); } catch (ActivityNotFoundException ex) { /* it seems some devices, even though they come with Android 4, * don't have the VPN components built into the system image. * com.android.vpndialogs/com.android.vpndialogs.ConfirmDialog * will not be found then */ VpnNotSupportedError.showWithMessage(this, R.string.vpn_not_supported); mWaitingForResult = false; } } else { /* user already granted permission to use VpnService */ onActivityResult(PREPARE_VPN_SERVICE, RESULT_OK, null); } } @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) { switch (requestCode) { case PREPARE_VPN_SERVICE: mWaitingForResult = false; if (resultCode == RESULT_OK && mProfileInfo != null) { if (mService != null) { mService.connect(mProfileInfo, true); } finish(); } else { /* this happens if the always-on VPN feature is activated by a different app or the user declined */ if (getSupportFragmentManager().isStateSaved()) { /* onActivityResult() might be called when we aren't active anymore e.g. if the * user pressed the home button, if the activity is started again we land here * before onNewIntent() is called */ return; } VpnNotSupportedError.showWithMessage(this, R.string.vpn_not_supported_no_permission); } break; default: super.onActivityResult(requestCode, resultCode, data); } } /** * Check if we are currently connected to a VPN connection * * @return true if currently connected */ private boolean isConnected() { if (mService == null) { return false; } if (mService .getErrorState() != VpnStateService.ErrorState.NO_ERROR) { /* allow reconnecting (even to a different profile) without confirmation if there is an error */ return false; } return (mService.getState() == State.CONNECTED || mService.getState() == State.CONNECTING); } /** * Start the given VPN profile * * @param profile VPN profile */ public void startVpnProfile(VpnProfile profile) { Bundle profileInfo = new Bundle(); profileInfo.putString(VpnProfileDataSource.KEY_UUID, profile.getUUID().toString()); profileInfo.putString(VpnProfileDataSource.KEY_USERNAME, profile.getUsername()); profileInfo.putString(VpnProfileDataSource.KEY_PASSWORD, profile.getPassword()); profileInfo.putBoolean(PROFILE_REQUIRES_PASSWORD, profile.getVpnType().has(VpnTypeFeature.USER_PASS)); profileInfo.putString(PROFILE_NAME, profile.getName()); removeFragmentByTag(DIALOG_TAG); if (isConnected()) { profileInfo.putBoolean(PROFILE_RECONNECT, mService.getProfile().getUUID().equals(profile.getUUID())); ConfirmationDialog dialog = new ConfirmationDialog(); dialog.setArguments(profileInfo); dialog.show(this.getSupportFragmentManager(), DIALOG_TAG); return; } startVpnProfile(profileInfo); } /** * Start the given VPN profile asking the user for a password if required. * * @param profileInfo data about the profile */ private void startVpnProfile(Bundle profileInfo) { if (profileInfo.getBoolean(PROFILE_REQUIRES_PASSWORD) && profileInfo.getString(VpnProfileDataSource.KEY_PASSWORD) == null) { LoginDialog login = new LoginDialog(); login.setArguments(profileInfo); login.show(getSupportFragmentManager(), DIALOG_TAG); return; } prepareVpnService(profileInfo); } /** * Start the VPN profile referred to by the given intent. Displays an error * if the profile doesn't exist. * * @param intent Intent that caused us to start this */ private void startVpnProfile(Intent intent) { VpnProfile profile = null; VpnProfileDataSource dataSource = new VpnProfileDataSource(this); dataSource.open(); String profileUUID = intent.getStringExtra(EXTRA_VPN_PROFILE_ID); if (profileUUID != null) { profile = dataSource.getVpnProfile(profileUUID); } else { long profileId = intent.getLongExtra(EXTRA_VPN_PROFILE_ID, 0); if (profileId > 0) { profile = dataSource.getVpnProfile(profileId); } } dataSource.close(); if (profile != null) { startVpnProfile(profile); } else { Toast.makeText(this, R.string.profile_not_found, Toast.LENGTH_LONG).show(); finish(); } } /** * Disconnect the current connection, if any (silently ignored if there is no connection). * * @param intent Intent that caused us to start this */ private void disconnect(Intent intent) { VpnProfile profile = null; removeFragmentByTag(DIALOG_TAG); String profileUUID = intent.getStringExtra(EXTRA_VPN_PROFILE_ID); if (profileUUID != null) { VpnProfileDataSource dataSource = new VpnProfileDataSource(this); dataSource.open(); profile = dataSource.getVpnProfile(profileUUID); dataSource.close(); } if (mService != null) { if (mService.getState() == State.CONNECTED || mService.getState() == State.CONNECTING) { if (profile != null && profile .equals(mService.getProfile())) { /* allow explicit termination without confirmation */ mService.disconnect(); finish(); return; } Bundle args = new Bundle(); args.putBoolean(PROFILE_DISCONNECT, true); ConfirmationDialog dialog = new ConfirmationDialog(); dialog.setArguments(args); dialog.show(this.getSupportFragmentManager(), DIALOG_TAG); } else { finish(); } } } /** * Handle the Intent of this Activity depending on its action */ private void handleIntent() { Intent intent = getIntent(); if (START_PROFILE.equals(intent.getAction())) { startVpnProfile(intent); } else if (DISCONNECT.equals(intent.getAction())) { disconnect(intent); } } /** * Dismiss dialog if shown */ public void removeFragmentByTag(String tag) { FragmentManager fm = getSupportFragmentManager(); Fragment login = fm.findFragmentByTag(tag); if (login != null) { FragmentTransaction ft = fm.beginTransaction(); ft.remove(login); ft.commit(); } } /** * Class that displays a confirmation dialog if a VPN profile is already connected * and then initiates the selected VPN profile if the user confirms the dialog. */ public static class ConfirmationDialog extends AppCompatDialogFragment { @Override public Dialog onCreateDialog(Bundle savedInstanceState) { final Bundle profileInfo = getArguments(); int icon = android.R.drawable.ic_dialog_alert; int title = R.string.connect_profile_question; int message = R.string.replaces_active_connection; int button = R.string.connect; if (profileInfo.getBoolean(PROFILE_RECONNECT)) { icon = android.R.drawable.ic_dialog_info; title = R.string.vpn_connected; message = R.string.vpn_profile_connected; button = R.string.reconnect; } else if (profileInfo.getBoolean(PROFILE_DISCONNECT)) { title = R.string.disconnect_question; message = R.string.disconnect_active_connection; button = R.string.disconnect; } DialogInterface.OnClickListener connectListener = new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { VpnProfileControlActivity activity = (VpnProfileControlActivity) getActivity(); activity.startVpnProfile(profileInfo); } }; DialogInterface.OnClickListener disconnectListener = new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { VpnProfileControlActivity activity = (VpnProfileControlActivity) getActivity(); if (activity.mService != null) { activity.mService.disconnect(); } activity.finish(); } }; DialogInterface.OnClickListener cancelListener = new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { getActivity().finish(); } }; AlertDialog.Builder builder = new AlertDialog.Builder(getActivity()).setIcon(icon) .setTitle(String.format(getString(title), profileInfo.getString(PROFILE_NAME))) .setMessage(message); if (profileInfo.getBoolean(PROFILE_DISCONNECT)) { builder.setPositiveButton(button, disconnectListener); } else { builder.setPositiveButton(button, connectListener); } if (profileInfo.getBoolean(PROFILE_RECONNECT)) { builder.setNegativeButton(R.string.disconnect, disconnectListener); builder.setNeutralButton(android.R.string.cancel, cancelListener); } else { builder.setNegativeButton(android.R.string.cancel, cancelListener); } return builder.create(); } @Override public void onCancel(DialogInterface dialog) { getActivity().finish(); } } /** * Class that displays a login dialog and initiates the selected VPN * profile if the user confirms the dialog. */ public static class LoginDialog extends AppCompatDialogFragment { @Override public Dialog onCreateDialog(Bundle savedInstanceState) { final Bundle profileInfo = getArguments(); LayoutInflater inflater = getActivity().getLayoutInflater(); View view = inflater.inflate(R.layout.login_dialog, null); EditText username = (EditText) view.findViewById(R.id.username); username.setText(profileInfo.getString(VpnProfileDataSource.KEY_USERNAME)); final EditText password = (EditText) view.findViewById(R.id.password); AlertDialog.Builder adb = new AlertDialog.Builder(getActivity()); adb.setView(view); adb.setTitle(getString(R.string.login_title)); adb.setPositiveButton(R.string.login_confirm, new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int whichButton) { VpnProfileControlActivity activity = (VpnProfileControlActivity) getActivity(); profileInfo.putString(VpnProfileDataSource.KEY_PASSWORD, password.getText().toString().trim()); activity.prepareVpnService(profileInfo); } }); adb.setNegativeButton(android.R.string.cancel, new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { getActivity().finish(); } }); return adb.create(); } @Override public void onCancel(DialogInterface dialog) { getActivity().finish(); } } /** * Class representing an error message which is displayed if VpnService is * not supported on the current device. */ public static class VpnNotSupportedError extends AppCompatDialogFragment { static final String ERROR_MESSAGE_ID = "org.strongswan.android.VpnNotSupportedError.MessageId"; public static void showWithMessage(AppCompatActivity activity, int messageId) { Bundle bundle = new Bundle(); bundle.putInt(ERROR_MESSAGE_ID, messageId); VpnNotSupportedError dialog = new VpnNotSupportedError(); dialog.setArguments(bundle); dialog.show(activity.getSupportFragmentManager(), DIALOG_TAG); } @Override public Dialog onCreateDialog(Bundle savedInstanceState) { final Bundle arguments = getArguments(); final int messageId = arguments.getInt(ERROR_MESSAGE_ID); return new AlertDialog.Builder(getActivity()).setTitle(R.string.vpn_not_supported_title) .setMessage(messageId).setCancelable(false) .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int id) { getActivity().finish(); } }).create(); } @Override public void onCancel(DialogInterface dialog) { getActivity().finish(); } } }