Java tutorial
/* * Copyright (C) 2012-2015 Dominik Schrmann <dominik@dominikschuermann.de> * Copyright (C) 2015 Adithya Abraham Philip <adithyaphilip@gmail.com> * * 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 org.sufficientlysecure.keychain.ui; import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.os.Messenger; import android.support.v4.app.Fragment; import android.support.v4.view.MotionEventCompat; import android.support.v7.widget.LinearLayoutManager; import android.support.v7.widget.RecyclerView; import android.support.v7.widget.helper.ItemTouchHelper; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuInflater; import android.view.MenuItem; import android.view.MotionEvent; import android.view.View; import android.view.ViewGroup; import android.widget.ImageView; import android.widget.TextView; import org.sufficientlysecure.keychain.R; import org.sufficientlysecure.keychain.ui.dialog.AddEditKeyserverDialogFragment; import org.sufficientlysecure.keychain.ui.util.FormattingUtils; import org.sufficientlysecure.keychain.ui.util.Notify; import org.sufficientlysecure.keychain.ui.util.recyclerview.ItemTouchHelperAdapter; import org.sufficientlysecure.keychain.ui.util.recyclerview.ItemTouchHelperDragCallback; import org.sufficientlysecure.keychain.ui.util.recyclerview.ItemTouchHelperViewHolder; import org.sufficientlysecure.keychain.ui.util.recyclerview.RecyclerItemClickListener; import org.sufficientlysecure.keychain.keyimport.ParcelableHkpKeyserver; import org.sufficientlysecure.keychain.util.Preferences; import java.util.ArrayList; import java.util.Collections; public class SettingsKeyserverFragment extends Fragment implements RecyclerItemClickListener.OnItemClickListener { private static final String ARG_KEYSERVER_ARRAY = "arg_keyserver_array"; private ItemTouchHelper mItemTouchHelper; private ArrayList<ParcelableHkpKeyserver> mKeyservers; private KeyserverListAdapter mAdapter; public static SettingsKeyserverFragment newInstance(ArrayList<ParcelableHkpKeyserver> keyservers) { Bundle args = new Bundle(); args.putParcelableArrayList(ARG_KEYSERVER_ARRAY, keyservers); SettingsKeyserverFragment fragment = new SettingsKeyserverFragment(); fragment.setArguments(args); return fragment; } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { return inflater.inflate(R.layout.settings_keyserver_fragment, null); } @Override public void onViewCreated(View view, Bundle savedInstanceState) { super.onViewCreated(view, savedInstanceState); mKeyservers = getArguments().getParcelableArrayList(ARG_KEYSERVER_ARRAY); mAdapter = new KeyserverListAdapter(mKeyservers); RecyclerView recyclerView = (RecyclerView) view.findViewById(R.id.keyserver_recycler_view); // recyclerView.setHasFixedSize(true); // the size of the first item changes recyclerView.setAdapter(mAdapter); recyclerView.setLayoutManager(new LinearLayoutManager(getActivity())); ItemTouchHelper.Callback callback = new ItemTouchHelperDragCallback(mAdapter); mItemTouchHelper = new ItemTouchHelper(callback); mItemTouchHelper.attachToRecyclerView(recyclerView); // for clicks recyclerView.addOnItemTouchListener(new RecyclerItemClickListener(getActivity(), this)); // can't use item decoration because it doesn't move with drag and drop // recyclerView.addItemDecoration(new DividerItemDecoration(getActivity(), null)); // We have a menu item to show in action bar. setHasOptionsMenu(true); } @Override public void onCreateOptionsMenu(final Menu menu, final MenuInflater inflater) { inflater.inflate(R.menu.keyserver_pref_menu, menu); super.onCreateOptionsMenu(menu, inflater); } @Override public boolean onOptionsItemSelected(MenuItem item) { switch (item.getItemId()) { case R.id.menu_add_keyserver: startAddKeyserverDialog(); return true; default: return super.onOptionsItemSelected(item); } } private void startAddKeyserverDialog() { // keyserver and position have no meaning startEditKeyserverDialog(AddEditKeyserverDialogFragment.DialogAction.ADD, null, -1); } private void startEditKeyserverDialog(AddEditKeyserverDialogFragment.DialogAction action, ParcelableHkpKeyserver keyserver, final int position) { Handler returnHandler = new Handler() { @Override public void handleMessage(Message message) { Bundle data = message.getData(); switch (message.what) { case AddEditKeyserverDialogFragment.MESSAGE_OKAY: { boolean deleted = data.getBoolean(AddEditKeyserverDialogFragment.MESSAGE_KEYSERVER_DELETED, false); if (deleted) { Notify.create(getActivity(), getActivity().getString(R.string.keyserver_preference_deleted, mKeyservers.get(position)), Notify.Style.OK).show(); deleteKeyserver(position); return; } boolean verified = data.getBoolean(AddEditKeyserverDialogFragment.MESSAGE_VERIFIED); if (verified) { Notify.create(getActivity(), R.string.add_keyserver_connection_verified, Notify.Style.OK) .show(); } else { Notify.create(getActivity(), R.string.add_keyserver_without_verification, Notify.Style.WARN) .show(); } ParcelableHkpKeyserver keyserver = data .getParcelable(AddEditKeyserverDialogFragment.MESSAGE_KEYSERVER); AddEditKeyserverDialogFragment.DialogAction dialogAction = (AddEditKeyserverDialogFragment.DialogAction) data .getSerializable(AddEditKeyserverDialogFragment.MESSAGE_DIALOG_ACTION); switch (dialogAction) { case ADD: addKeyserver(keyserver); break; case EDIT: editKeyserver(keyserver, position); break; } break; } } } }; // Create a new Messenger for the communication back Messenger messenger = new Messenger(returnHandler); AddEditKeyserverDialogFragment dialogFragment = AddEditKeyserverDialogFragment.newInstance(messenger, action, keyserver, position); dialogFragment.show(getFragmentManager(), "addKeyserverDialog"); } private void addKeyserver(ParcelableHkpKeyserver keyserver) { mKeyservers.add(keyserver); mAdapter.notifyItemInserted(mKeyservers.size() - 1); saveKeyserverList(); } private void editKeyserver(ParcelableHkpKeyserver newKeyserver, int position) { mKeyservers.set(position, newKeyserver); mAdapter.notifyItemChanged(position); saveKeyserverList(); } private void deleteKeyserver(int position) { if (mKeyservers.size() == 1) { Notify.create(getActivity(), R.string.keyserver_preference_cannot_delete_last, Notify.Style.ERROR) .show(); return; } mKeyservers.remove(position); // we use this mAdapter.notifyItemRemoved(position); if (position == 0 && mKeyservers.size() > 0) { // if we deleted the first item, we need the adapter to redraw the new first item mAdapter.notifyItemChanged(0); } saveKeyserverList(); } private void saveKeyserverList() { Preferences.getPreferences(getActivity()).setKeyServers(mKeyservers); } @Override public void onItemClick(View view, int position) { startEditKeyserverDialog(AddEditKeyserverDialogFragment.DialogAction.EDIT, mKeyservers.get(position), position); } public class KeyserverListAdapter extends RecyclerView.Adapter<KeyserverListAdapter.ViewHolder> implements ItemTouchHelperAdapter { private final ArrayList<ParcelableHkpKeyserver> mKeyservers; public KeyserverListAdapter(ArrayList<ParcelableHkpKeyserver> keyservers) { mKeyservers = keyservers; } @Override public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.settings_keyserver_item, parent, false); return new ViewHolder(view); } @Override public void onBindViewHolder(final ViewHolder holder, int position) { holder.keyserverUrl.setText(mKeyservers.get(position).getUrl()); // Start a drag whenever the handle view it touched holder.dragHandleView.setOnTouchListener(new View.OnTouchListener() { @Override public boolean onTouch(View v, MotionEvent event) { if (MotionEventCompat.getActionMasked(event) == MotionEvent.ACTION_DOWN) { mItemTouchHelper.startDrag(holder); } return false; } }); selectUnselectKeyserver(holder, position); } private void selectUnselectKeyserver(ViewHolder holder, int position) { if (position == 0) { holder.showAsSelectedKeyserver(); } else { holder.showAsUnselectedKeyserver(); } } @Override public void onItemMove(RecyclerView.ViewHolder source, RecyclerView.ViewHolder target, int fromPosition, int toPosition) { Collections.swap(mKeyservers, fromPosition, toPosition); saveKeyserverList(); selectUnselectKeyserver((ViewHolder) target, fromPosition); // we don't want source to change color while dragging, therefore we just set // isSelectedKeyserver instead of selectUnselectKeyserver ((ViewHolder) source).isSelectedKeyserver = toPosition == 0; notifyItemMoved(fromPosition, toPosition); } @Override public int getItemCount() { return mKeyservers.size(); } public class ViewHolder extends RecyclerView.ViewHolder implements ItemTouchHelperViewHolder { public final ViewGroup outerLayout; public final TextView selectedServerLabel; public final TextView keyserverUrl; public final ImageView dragHandleView; private boolean isSelectedKeyserver = false; public ViewHolder(View itemView) { super(itemView); outerLayout = (ViewGroup) itemView.findViewById(R.id.outer_layout); selectedServerLabel = (TextView) itemView.findViewById(R.id.selected_keyserver_title); keyserverUrl = (TextView) itemView.findViewById(R.id.keyserver_tv); dragHandleView = (ImageView) itemView.findViewById(R.id.drag_handle); itemView.setClickable(true); } public void showAsSelectedKeyserver() { isSelectedKeyserver = true; selectedServerLabel.setVisibility(View.VISIBLE); outerLayout.setBackgroundColor( FormattingUtils.getColorFromAttr(getContext(), R.attr.colorPrimaryDark)); } public void showAsUnselectedKeyserver() { isSelectedKeyserver = false; selectedServerLabel.setVisibility(View.GONE); outerLayout.setBackgroundColor(0); } @Override public void onItemSelected() { selectedServerLabel.setVisibility(View.GONE); itemView.setBackgroundColor( FormattingUtils.getColorFromAttr(getContext(), R.attr.colorBrightToolbar)); } @Override public void onItemClear() { if (isSelectedKeyserver) { showAsSelectedKeyserver(); } else { showAsUnselectedKeyserver(); } } } } }