Java tutorial
/* * 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 tv.piratemedia.flightcontroller; import android.app.ActionBar; import android.app.Activity; import android.bluetooth.BluetoothAdapter; import android.bluetooth.BluetoothDevice; import android.content.Intent; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.support.annotation.Nullable; import android.support.v4.app.Fragment; import android.support.v4.app.FragmentActivity; import android.util.Log; import android.view.KeyEvent; 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.view.inputmethod.EditorInfo; import android.widget.CompoundButton; import android.widget.SeekBar; import android.widget.Switch; import android.widget.TextView; import android.widget.Toast; import com.larswerkman.holocolorpicker.ColorPicker; import org.json.JSONException; import org.json.JSONObject; /** * This fragment controls Bluetooth to communicate with other devices. */ public class BluetoothControlFragment extends Fragment { private static final String TAG = "ControlFragment"; // Intent request codes private static final int REQUEST_CONNECT_DEVICE_SECURE = 1; private static final int REQUEST_CONNECT_DEVICE_INSECURE = 2; private static final int REQUEST_ENABLE_BT = 3; /** * Name of the connected device */ private String mConnectedDeviceName = null; /** * String buffer for outgoing messages */ private StringBuffer mOutStringBuffer; /** * Local Bluetooth adapter */ private BluetoothAdapter mBluetoothAdapter = null; /** * Member object for the chat services */ private BluetoothFlightControllerService mFlightControllerService = null; private TextView altitude; private TextView longitude; private TextView latitude; private TextView pitchCorrection; private TextView rollCorrection; public JoystickView LeftStick; public JoystickView RightStick; public VerticalSeekBar throttle; private boolean showMessage = true; private Handler handler; private int ThrottleCache = 0; private Handler timeoutHandler; private boolean blocking = false; private float SpeedDivider = 10.0f; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setHasOptionsMenu(true); // Get local Bluetooth adapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter(); // If the adapter is null, then Bluetooth is not supported if (mBluetoothAdapter == null) { FragmentActivity activity = getActivity(); Toast.makeText(activity, "Bluetooth is not available", Toast.LENGTH_LONG).show(); activity.finish(); } handler = new Handler(); } @Override public void onStart() { super.onStart(); // If BT is not on, request that it be enabled. // setupChat() will then be called during onActivityResult if (!mBluetoothAdapter.isEnabled()) { Intent enableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE); startActivityForResult(enableIntent, REQUEST_ENABLE_BT); // Otherwise, setup the chat session } else if (mFlightControllerService == null) { setupChat(); } } @Override public void onDestroy() { super.onDestroy(); if (mFlightControllerService != null) { mFlightControllerService.stop(); } } @Override public void onResume() { super.onResume(); // Performing this check in onResume() covers the case in which BT was // not enabled during onStart(), so we were paused to enable it... // onResume() will be called when ACTION_REQUEST_ENABLE activity returns. if (mFlightControllerService != null) { // Only if the state is STATE_NONE, do we know that we haven't started already if (mFlightControllerService.getState() == BluetoothFlightControllerService.STATE_NONE) { // Start the Bluetooth chat services mFlightControllerService.start(); } } } @Override public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { return inflater.inflate(R.layout.control_fragment, container, false); } @Override public void onViewCreated(View view, @Nullable Bundle savedInstanceState) { timeoutHandler = new Handler(); throttle = (VerticalSeekBar) view.findViewById(R.id.throttle); final ColorPicker ledColor = (ColorPicker) view.findViewById(R.id.ledColor); final Switch ledOn = (Switch) view.findViewById(R.id.ledSwitch); throttle.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() { @Override public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) { ThrottleCache = progress; if (!blocking) { JSONObject msg = new JSONObject(); try { msg.put("action", "throttle"); msg.put("value", progress); } catch (JSONException e) { e.printStackTrace(); } sendMessage(msg.toString()); timeoutHandler.postDelayed(new Runnable() { @Override public void run() { blocking = false; JSONObject msg = new JSONObject(); try { msg.put("action", "throttle"); msg.put("value", ThrottleCache); } catch (JSONException e) { e.printStackTrace(); } sendMessage(msg.toString()); } }, 150); blocking = true; } } @Override public void onStartTrackingTouch(SeekBar seekBar) { } @Override public void onStopTrackingTouch(SeekBar seekBar) { JSONObject msg = new JSONObject(); try { msg.put("action", "throttle"); msg.put("value", seekBar.getProgress()); } catch (JSONException e) { e.printStackTrace(); } sendMessage(msg.toString()); } }); ledColor.setShowOldCenterColor(false); ledColor.setOnColorChangedListener(new ColorPicker.OnColorChangedListener() { @Override public void onColorChanged(int i) { if (!blocking) { JSONObject msg = new JSONObject(); try { msg.put("action", "led"); msg.put("color", i); msg.put("on", ledOn.isChecked()); } catch (JSONException e) { e.printStackTrace(); } sendMessage(msg.toString()); timeoutHandler.postDelayed(new Runnable() { @Override public void run() { blocking = false; } }, 150); blocking = true; } } }); ledOn.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() { @Override public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { JSONObject msg = new JSONObject(); try { msg.put("action", "led"); msg.put("color", ledColor.getColor()); msg.put("on", isChecked); } catch (JSONException e) { e.printStackTrace(); } sendMessage(msg.toString()); } }); longitude = (TextView) view.findViewById(R.id.longitude); latitude = (TextView) view.findViewById(R.id.latitude); altitude = (TextView) view.findViewById(R.id.altitude); pitchCorrection = (TextView) view.findViewById(R.id.picth_correction); rollCorrection = (TextView) view.findViewById(R.id.roll_correction); LeftStick = (JoystickView) view.findViewById(R.id.left_stick); RightStick = (JoystickView) view.findViewById(R.id.right_stick); LeftStick.setOnJoystickMoveListener(new JoystickView.OnJoystickMoveListener() { @Override public void onValueChanged(int angle, int power, int direction) { JSONObject msg = new JSONObject(); try { msg.put("action", "movement"); msg.put("pitch", 0); msg.put("roll", 0); } catch (JSONException e) { e.printStackTrace(); } if (power == 0) { sendMessage(msg.toString()); } else { if (angle > -10 && angle < 10) { //just pitch forwards try { msg.put("pitch", Math.round((double) power / SpeedDivider)); } catch (JSONException e) { e.printStackTrace(); } } else if (angle < -170 || angle > 170) { //just pitch backwards try { msg.put("pitch", -Math.round((double) power / SpeedDivider)); } catch (JSONException e) { e.printStackTrace(); } } else if (angle < -80 && angle > -100) { //just roll Left try { msg.put("roll", -Math.round((double) power / SpeedDivider)); } catch (JSONException e) { e.printStackTrace(); } } else if (angle > 80 && angle < 100) { //just roll right try { msg.put("roll", Math.round((double) power / SpeedDivider)); } catch (JSONException e) { e.printStackTrace(); } } else { // combination int pitch = 0; int roll = 0; if (angle > 0 && angle < 90) { //forwards and right roll = Math.round(power * (float) angle / 90.0f); pitch = Math.round(power - roll); } else if (angle > 90 && angle < 180) { angle = angle - 90; //backwards and right pitch = Math.round(power * (float) angle / 90.0f); roll = Math.round(power - pitch); pitch = -pitch; } else if (angle < 0 && angle > -90) { angle = -angle; //forwards and left roll = Math.round(power * (float) angle / 90.0f); pitch = Math.round(power - roll); roll = -roll; } else { angle = (-angle) - 90; // backwards and right pitch = Math.round(power * (float) angle / 90.0f); roll = -Math.round(power - pitch); pitch = -pitch; } try { msg.put("pitch", Math.round((double) pitch / SpeedDivider)); msg.put("roll", Math.round((double) roll / SpeedDivider)); } catch (JSONException e) { e.printStackTrace(); } } sendMessage(msg.toString()); } } }, 150); RightStick.setOnJoystickMoveListener(new JoystickView.OnJoystickMoveListener() { @Override public void onValueChanged(int angle, int power, int direction) { JSONObject msg = new JSONObject(); try { msg.put("action", "movement"); msg.put("yaw", 0); } catch (JSONException e) { e.printStackTrace(); } int yaw = 0; int pitch = 0; if (angle > 0 && angle < 90) { //forwards and right yaw = Math.round(power * (float) angle / 90.0f); pitch = Math.round(power - yaw); } else if (angle > 90 && angle < 180) { angle = angle - 90; //backwards and right pitch = Math.round(power * (float) angle / 90.0f); yaw = Math.round(power - pitch); pitch = -pitch; } else if (angle < 0 && angle > -90) { angle = -angle; //forwards and left yaw = Math.round(power * (float) angle / 90.0f); pitch = Math.round(power - yaw); yaw = -yaw; } else { angle = (-angle) - 90; // backwards and right pitch = Math.round(power * (float) angle / 90.0f); yaw = -Math.round(power - pitch); pitch = -pitch; } try { msg.put("yaw", Math.round((double) yaw / SpeedDivider)); } catch (JSONException e) { e.printStackTrace(); } sendMessage(msg.toString()); } }, 150); } /** * Set up the UI and background operations for chat. */ private void setupChat() { Log.d(TAG, "setupChat()"); // Initialize the BluetoothChatService to perform bluetooth connections mFlightControllerService = new BluetoothFlightControllerService(getActivity(), mHandler); // Initialize the buffer for outgoing messages mOutStringBuffer = new StringBuffer(""); } /** * Makes this device discoverable. */ private void ensureDiscoverable() { if (mBluetoothAdapter.getScanMode() != BluetoothAdapter.SCAN_MODE_CONNECTABLE_DISCOVERABLE) { Intent discoverableIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_DISCOVERABLE); discoverableIntent.putExtra(BluetoothAdapter.EXTRA_DISCOVERABLE_DURATION, 300); startActivity(discoverableIntent); } } /** * Sends a message. * * @param message A string of text to send. */ private void sendMessage(String message) { // Check that we're actually connected before trying anything try { if (mFlightControllerService.getState() != BluetoothFlightControllerService.STATE_CONNECTED) { if (showMessage) { Toast.makeText(getActivity(), R.string.not_connected, Toast.LENGTH_SHORT).show(); showMessage = false; handler.postDelayed(new Runnable() { @Override public void run() { showMessage = true; } }, 3000); } return; } // Check that there's actually something to send if (message.length() > 0) { // Get the message bytes and tell the BluetoothChatService to write byte[] send = message.getBytes(); mFlightControllerService.write(send); // Reset out string buffer to zero and clear the edit text field mOutStringBuffer.setLength(0); } } catch (Exception e) { } } /** * The action listener for the EditText widget, to listen for the return key */ private TextView.OnEditorActionListener mWriteListener = new TextView.OnEditorActionListener() { public boolean onEditorAction(TextView view, int actionId, KeyEvent event) { // If the action is a key-up event on the return key, send the message if (actionId == EditorInfo.IME_NULL && event.getAction() == KeyEvent.ACTION_UP) { String message = view.getText().toString(); sendMessage(message); } return true; } }; /** * Updates the status on the action bar. * * @param resId a string resource ID */ private void setStatus(int resId) { FragmentActivity activity = getActivity(); if (null == activity) { return; } final ActionBar actionBar = activity.getActionBar(); if (null == actionBar) { return; } actionBar.setSubtitle(resId); } /** * Updates the status on the action bar. * * @param subTitle status */ private void setStatus(CharSequence subTitle) { FragmentActivity activity = getActivity(); if (null == activity) { return; } final ActionBar actionBar = activity.getActionBar(); if (null == actionBar) { return; } actionBar.setSubtitle(subTitle); } /** * The Handler that gets information back from the BluetoothChatService */ private final Handler mHandler = new Handler() { @Override public void handleMessage(Message msg) { FragmentActivity activity = getActivity(); switch (msg.what) { case Constants.MESSAGE_STATE_CHANGE: switch (msg.arg1) { case BluetoothFlightControllerService.STATE_CONNECTED: setStatus(getString(R.string.title_connected_to, mConnectedDeviceName)); break; case BluetoothFlightControllerService.STATE_CONNECTING: setStatus(R.string.title_connecting); break; case BluetoothFlightControllerService.STATE_LISTEN: case BluetoothFlightControllerService.STATE_NONE: setStatus(R.string.title_not_connected); break; } break; case Constants.MESSAGE_WRITE: byte[] writeBuf = (byte[]) msg.obj; // construct a string from the buffer String writeMessage = new String(writeBuf); break; case Constants.MESSAGE_READ: byte[] readBuf = (byte[]) msg.obj; // construct a string from the valid bytes in the buffer String readMessage = new String(readBuf, 0, msg.arg1); try { parseMessage(new JSONObject(readMessage)); } catch (JSONException e) { e.printStackTrace(); } break; case Constants.MESSAGE_DEVICE_NAME: // save the connected device's name mConnectedDeviceName = msg.getData().getString(Constants.DEVICE_NAME); if (null != activity) { Toast.makeText(activity, "Connected to " + mConnectedDeviceName, Toast.LENGTH_SHORT).show(); } break; case Constants.MESSAGE_TOAST: if (null != activity) { Toast.makeText(activity, msg.getData().getString(Constants.TOAST), Toast.LENGTH_SHORT).show(); } break; } } }; public void parseMessage(JSONObject m) { try { switch (m.getString("action")) { case "altitude_update": updateAltitude(m.getDouble("value")); break; case "location_update": updateLocation(m.getDouble("long"), m.getDouble("lat")); break; case "throttle_update": throttle.setProgress(m.getInt("value")); break; case "correction_update": updateCorrection(m.getInt("pitch"), m.getInt("roll")); } } catch (JSONException e) { e.printStackTrace(); } } public void updateLocation(double Long, double Lat) { longitude.setText("" + Long); latitude.setText("" + Lat); } public void updateCorrection(int pitch, int roll) { pitchCorrection.setText("" + pitch); rollCorrection.setText("" + roll); } public void updateAltitude(double Alt) { altitude.setText(String.format("%.1f", Alt)); } public void onActivityResult(int requestCode, int resultCode, Intent data) { switch (requestCode) { case REQUEST_CONNECT_DEVICE_SECURE: // When DeviceListActivity returns with a device to connect if (resultCode == Activity.RESULT_OK) { connectDevice(data, true); } break; case REQUEST_CONNECT_DEVICE_INSECURE: // When DeviceListActivity returns with a device to connect if (resultCode == Activity.RESULT_OK) { connectDevice(data, false); } break; case REQUEST_ENABLE_BT: // When the request to enable Bluetooth returns if (resultCode == Activity.RESULT_OK) { // Bluetooth is now enabled, so set up a chat session setupChat(); } else { // User did not enable Bluetooth or an error occurred Log.d(TAG, "BT not enabled"); Toast.makeText(getActivity(), R.string.bt_not_enabled_leaving, Toast.LENGTH_SHORT).show(); getActivity().finish(); } } } /** * Establish connection with other divice * * @param data An {@link Intent} with {@link DeviceListActivity#EXTRA_DEVICE_ADDRESS} extra. * @param secure Socket Security type - Secure (true) , Insecure (false) */ private void connectDevice(Intent data, boolean secure) { // Get the device MAC address String address = data.getExtras().getString(DeviceListActivity.EXTRA_DEVICE_ADDRESS); // Get the BluetoothDevice object BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(address); // Attempt to connect to the device mFlightControllerService.connect(device, secure); } @Override public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) { inflater.inflate(R.menu.controller, menu); } @Override public boolean onOptionsItemSelected(MenuItem item) { switch (item.getItemId()) { case R.id.secure_connect_scan: { // Launch the DeviceListActivity to see devices and do scan Intent serverIntent = new Intent(getActivity(), DeviceListActivity.class); startActivityForResult(serverIntent, REQUEST_CONNECT_DEVICE_SECURE); return true; } case R.id.insecure_connect_scan: { // Launch the DeviceListActivity to see devices and do scan Intent serverIntent = new Intent(getActivity(), DeviceListActivity.class); startActivityForResult(serverIntent, REQUEST_CONNECT_DEVICE_INSECURE); return true; } case R.id.discoverable: { // Ensure this device is discoverable by others ensureDiscoverable(); return true; } } return false; } }