Java tutorial
/* * Copyright 2014 Maximilian Salomon. * * 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 3 of the License, or * (at your option) any later version. * * 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. * * You should have received a copy of the GNU General Public License * along with this program. If not, see http://www.gnu.org/licenses/. */ package de.msal.shoutemo.ui.chat; import android.app.Activity; import android.app.Fragment; import android.app.LoaderManager; import android.content.BroadcastReceiver; import android.content.Context; import android.content.CursorLoader; import android.content.Intent; import android.content.IntentFilter; import android.content.Loader; import android.database.Cursor; import android.os.Bundle; import android.support.annotation.Nullable; import android.support.v4.content.LocalBroadcastManager; import android.text.Editable; import android.text.TextUtils; import android.text.TextWatcher; 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.animation.Animation; import android.view.animation.AnimationUtils; import android.view.inputmethod.InputMethodManager; import android.widget.EditText; import android.widget.GridView; import android.widget.ImageButton; import android.widget.ImageView; import android.widget.ListView; import de.msal.shoutemo.R; import de.msal.shoutemo.connector.GetPostsService; import de.msal.shoutemo.connector.SendPostTask; import de.msal.shoutemo.connector.model.Message; import de.msal.shoutemo.db.ChatDb; import de.msal.shoutemo.ui.TitleSetListener; public class ChatFragment extends Fragment implements LoaderManager.LoaderCallbacks<Cursor> { private final static int LOADER_ID_MESSAGES = 0; private ListAdapter mListAdapter; private BroadcastReceiver mReceiver; private TitleSetListener mCallback; private GridView mEmoticonGrid; private ImageButton mKeyboardButton; private EditText mInputField; private ImageButton mSendButton; /** * Use this factory method to create a new instance of this fragment using the provided * parameters. * * @return A new instance of fragment LightMeterFragment. */ public static ChatFragment newInstance() { ChatFragment fragment = new ChatFragment(); Bundle args = new Bundle(); fragment.setArguments(args); return fragment; } public ChatFragment() { } @Override public void onAttach(Activity activity) { super.onAttach(activity); try { mCallback = (TitleSetListener) activity; } catch (ClassCastException e) { throw new ClassCastException(activity.toString() + " must implement OnHeadlineSelectedListener"); } } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setHasOptionsMenu(true); } @Override public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) { View view = inflater.inflate(R.layout.fragment_chat, container, false); /* set the fragment title of the toolbar */ mCallback.setTitle(getString(R.string.app_name)); /* INPUT FIELD WHERE THE MESSAGE IS COMPOSED */ mInputField = (EditText) view.findViewById(R.id.et_input); /* display a blinking dot to show the refresh status */ final ImageView updateStatus = (ImageView) view.findViewById(R.id.ib_update_indicator); mReceiver = new BroadcastReceiver() { @Override public void onReceive(Context context, Intent intent) { boolean enabled = intent.getBooleanExtra(GetPostsService.INTENT_UPDATE_ENABLED, false); if (enabled) { updateStatus.setVisibility(View.VISIBLE); } else { updateStatus.setVisibility(View.INVISIBLE); } } }; /* SEND MESSAGE BUTTON */ mSendButton = (ImageButton) view.findViewById(R.id.ib_send); // initially the mInputField is empty, so disable the send button mSendButton.setVisibility(View.GONE); // Send message when clicked on SEND-BUTTON mSendButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { if (mInputField.getText() != null && !TextUtils.isEmpty(mInputField.getText())) { new SendPostTask(getActivity()).execute(mInputField.getText().toString()); mInputField.setText(""); } } }); mEmoticonGrid = (GridView) view.findViewById(R.id.emoticons_grid); /* set the adapter for the emoticons */ mEmoticonGrid .setAdapter(new EmoticonsAdapter(getActivity(), new EmoticonsAdapter.OnEmoticonClickListener() { @Override public void onEmoticonClick(String bbcode) { mInputField.getText().replace(mInputField.getSelectionStart(), mInputField.getSelectionEnd(), " " + bbcode + " "); } })); /* A BUTTON WHICH SWITCHES BETWEEN SOFT KEYBOARD AND EMOTICON SELECTOR */ mKeyboardButton = (ImageButton) view.findViewById(R.id.ib_emoticons); /* Showing and dismissing popup on clicking EMOTICONS-BUTTON */ mKeyboardButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { if (mEmoticonGrid.getVisibility() == View.VISIBLE) { mKeyboardButton.setImageResource(R.drawable.ic_action_keyboard_alt_white_24dp); mEmoticonGrid.setVisibility(View.GONE); } else { mKeyboardButton.setImageResource(R.drawable.ic_action_keyboard_arrow_down_white_24dp); mEmoticonGrid.setVisibility(View.VISIBLE); hideKeyboard(); } } }); /* LIST STUFF */ mListAdapter = new ListAdapter(getActivity(), null, 0); ListView listView = (ListView) view.findViewById(android.R.id.list); listView.setVerticalScrollBarEnabled(true); listView.setAdapter(mListAdapter); this.getLoaderManager().initLoader(LOADER_ID_MESSAGES, null, this); return view; } @Override public void onViewCreated(View view, Bundle savedInstanceState) { super.onViewCreated(view, savedInstanceState); /* receive and handle share intent */ Intent intent = getActivity().getIntent(); String type = intent.getType(); if (intent.getAction().equals(Intent.ACTION_SEND) && type != null) { if (type.equals("text/plain")) { String sharedText = intent.getStringExtra(Intent.EXTRA_TEXT); if (sharedText != null) { mInputField.setText(sharedText); } } } /* hide send-button, if no text is entered */ mInputField.addTextChangedListener(new TextWatcher() { @Override public void beforeTextChanged(CharSequence s, int start, int count, int after) { } @Override public void onTextChanged(CharSequence s, int start, int before, int count) { } @Override public void afterTextChanged(Editable s) { if (mSendButton.getVisibility() == View.VISIBLE && s.length() == 0) { Animation pushOut = AnimationUtils.loadAnimation(getActivity(), R.anim.push_out); mSendButton.startAnimation(pushOut); mSendButton.setVisibility(View.GONE); } else if (mSendButton.getVisibility() == View.GONE && s.length() >= 1) { Animation pushIn = AnimationUtils.loadAnimation(getActivity(), R.anim.push_in); mSendButton.startAnimation(pushIn); mSendButton.setVisibility(View.VISIBLE); } } }); /* */ mInputField.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { mKeyboardButton.setImageResource(R.drawable.ic_action_keyboard_alt_white_24dp); mEmoticonGrid.setVisibility(View.GONE); } }); } @Override public void onStart() { super.onStart(); LocalBroadcastManager.getInstance(getActivity()).registerReceiver((mReceiver), new IntentFilter(GetPostsService.INTENT_UPDATE)); } @Override public void onResume() { super.onResume(); /* retrieve data */ getActivity().startService(new Intent(getActivity(), GetPostsService.class)); } @Override public void onPause() { super.onPause(); /* stop retrieving data */ getActivity().stopService(new Intent(getActivity(), GetPostsService.class)); } @Override public void onStop() { LocalBroadcastManager.getInstance(getActivity()).unregisterReceiver(mReceiver); super.onStop(); } @Override public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) { super.onCreateOptionsMenu(menu, inflater); inflater.inflate(R.menu.chat, menu); } @Override public boolean onOptionsItemSelected(MenuItem item) { Bundle args = new Bundle(); switch (item.getItemId()) { /* filters */ case R.id.menu_filter_all: getLoaderManager().restartLoader(LOADER_ID_MESSAGES, null, this); item.setChecked(true); break; case R.id.menu_filter_shouts: args.putString("WHERE", ChatDb.Messages.COLUMN_NAME_TYPE + " = '" + Message.Type.SHOUT + "'"); getLoaderManager().restartLoader(LOADER_ID_MESSAGES, args, this); item.setChecked(true); break; case R.id.menu_filter_global: args.putString("WHERE", ChatDb.Messages.COLUMN_NAME_TYPE + " = '" + Message.Type.GLOBAL + "'"); getLoaderManager().restartLoader(LOADER_ID_MESSAGES, args, this); item.setChecked(true); break; case R.id.menu_filter_competitions: args.putString("WHERE", ChatDb.Messages.COLUMN_NAME_TYPE + " = '" + Message.Type.COMPETITION + "'"); getLoaderManager().restartLoader(LOADER_ID_MESSAGES, args, this); item.setChecked(true); break; case R.id.menu_filter_awards: args.putString("WHERE", ChatDb.Messages.COLUMN_NAME_TYPE + " = '" + Message.Type.AWARD + "'"); getLoaderManager().restartLoader(LOADER_ID_MESSAGES, args, this); item.setChecked(true); break; case R.id.menu_filter_promotions: args.putString("WHERE", ChatDb.Messages.COLUMN_NAME_TYPE + " = '" + Message.Type.PROMOTION + "'"); getLoaderManager().restartLoader(LOADER_ID_MESSAGES, args, this); item.setChecked(true); break; case R.id.menu_filter_threads: args.putString("WHERE", ChatDb.Messages.COLUMN_NAME_TYPE + " = '" + Message.Type.THREAD + "'"); getLoaderManager().restartLoader(LOADER_ID_MESSAGES, args, this); item.setChecked(true); break; } return super.onOptionsItemSelected(item); } private void hideKeyboard() { InputMethodManager inputManager = (InputMethodManager) getActivity() .getSystemService(Context.INPUT_METHOD_SERVICE); // check if no view has focus: View view = getActivity().getCurrentFocus(); if (view != null) { inputManager.hideSoftInputFromWindow(view.getWindowToken(), InputMethodManager.HIDE_NOT_ALWAYS); } } @Override public Loader<Cursor> onCreateLoader(int id, Bundle args) { switch (id) { case LOADER_ID_MESSAGES: String where = null; if (args != null) { where = args.getString("WHERE"); } return new CursorLoader(getActivity(), ChatDb.Posts.CONTENT_URI, null, where, null, null); default: return null; } } @Override public void onLoadFinished(Loader<Cursor> objectLoader, Cursor data) { mListAdapter.swapCursor(data); } @Override public void onLoaderReset(Loader<Cursor> cursorLoader) { mListAdapter.swapCursor(null); } }