Java tutorial
/* * Copyright (C) 2013 Dominik Schrmann <dominik@dominikschuermann.de> * * 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.adapter; import java.util.HashMap; import java.util.Set; import org.sufficientlysecure.keychain.Constants; import org.sufficientlysecure.keychain.R; import org.sufficientlysecure.keychain.pgp.PgpKeyHelper; import org.sufficientlysecure.keychain.provider.KeychainContract; import org.sufficientlysecure.keychain.util.Log; import se.emilsjolander.stickylistheaders.StickyListHeadersAdapter; import android.annotation.SuppressLint; import android.content.Context; import android.database.Cursor; import android.graphics.Color; import android.support.v4.widget.CursorAdapter; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.TextView; /** * Implements StickyListHeadersAdapter from library */ public class KeyListPublicAdapter extends CursorAdapter implements StickyListHeadersAdapter { private LayoutInflater mInflater; private int mSectionColumnIndex; private int mIndexUserId; private int mIndexIsRevoked; @SuppressLint("UseSparseArrays") private HashMap<Integer, Boolean> mSelection = new HashMap<Integer, Boolean>(); public KeyListPublicAdapter(Context context, Cursor c, int flags, int sectionColumnIndex) { super(context, c, flags); mInflater = LayoutInflater.from(context); mSectionColumnIndex = sectionColumnIndex; initIndex(c); } @Override public Cursor swapCursor(Cursor newCursor) { initIndex(newCursor); return super.swapCursor(newCursor); } /** * Get column indexes for performance reasons just once in constructor and swapCursor. For a * performance comparison see http://stackoverflow.com/a/17999582 * * @param cursor */ private void initIndex(Cursor cursor) { if (cursor != null) { mIndexUserId = cursor.getColumnIndexOrThrow(KeychainContract.UserIds.USER_ID); mIndexIsRevoked = cursor.getColumnIndexOrThrow(KeychainContract.Keys.IS_REVOKED); } } /** * Bind cursor data to the item list view * <p/> * NOTE: CursorAdapter already implements the ViewHolder pattern in its getView() method. Thus * no ViewHolder is required here. */ @Override public void bindView(View view, Context context, Cursor cursor) { TextView mainUserId = (TextView) view.findViewById(R.id.mainUserId); TextView mainUserIdRest = (TextView) view.findViewById(R.id.mainUserIdRest); TextView revoked = (TextView) view.findViewById(R.id.revoked); String userId = cursor.getString(mIndexUserId); String[] userIdSplit = PgpKeyHelper.splitUserId(userId); if (userIdSplit[0] != null) { mainUserId.setText(userIdSplit[0]); } else { mainUserId.setText(R.string.user_id_no_name); } if (userIdSplit[1] != null) { mainUserIdRest.setText(userIdSplit[1]); mainUserIdRest.setVisibility(View.VISIBLE); } else { mainUserIdRest.setVisibility(View.GONE); } boolean isRevoked = cursor.getInt(mIndexIsRevoked) > 0; if (isRevoked) { revoked.setVisibility(View.VISIBLE); } else { revoked.setVisibility(View.GONE); } } @Override public View newView(Context context, Cursor cursor, ViewGroup parent) { return mInflater.inflate(R.layout.key_list_public_item, null); } /** * Creates a new header view and binds the section headers to it. It uses the ViewHolder * pattern. Most functionality is similar to getView() from Android's CursorAdapter. * <p/> * NOTE: The variables mDataValid and mCursor are available due to the super class * CursorAdapter. */ @Override public View getHeaderView(int position, View convertView, ViewGroup parent) { HeaderViewHolder holder; if (convertView == null) { holder = new HeaderViewHolder(); convertView = mInflater.inflate(R.layout.key_list_public_header, parent, false); holder.text = (TextView) convertView.findViewById(R.id.stickylist_header_text); convertView.setTag(holder); } else { holder = (HeaderViewHolder) convertView.getTag(); } if (!mDataValid) { // no data available at this point Log.d(Constants.TAG, "getHeaderView: No data available at this point!"); return convertView; } if (!mCursor.moveToPosition(position)) { throw new IllegalStateException("couldn't move cursor to position " + position); } // set header text as first char in user id String userId = mCursor.getString(mSectionColumnIndex); String headerText = convertView.getResources().getString(R.string.user_id_no_name); if (userId != null && userId.length() > 0) { headerText = "" + mCursor.getString(mSectionColumnIndex).subSequence(0, 1).charAt(0); } holder.text.setText(headerText); return convertView; } /** * Header IDs should be static, position=1 should always return the same Id that is. */ @Override public long getHeaderId(int position) { if (!mDataValid) { // no data available at this point Log.d(Constants.TAG, "getHeaderView: No data available at this point!"); return -1; } if (!mCursor.moveToPosition(position)) { throw new IllegalStateException("couldn't move cursor to position " + position); } // return the first character of the name as ID because this is what // headers are based upon String userId = mCursor.getString(mSectionColumnIndex); if (userId != null && userId.length() > 0) { return userId.subSequence(0, 1).charAt(0); } else { return Long.MAX_VALUE; } } class HeaderViewHolder { TextView text; } /** * -------------------------- MULTI-SELECTION METHODS -------------- */ public void setNewSelection(int position, boolean value) { mSelection.put(position, value); notifyDataSetChanged(); } public boolean isPositionChecked(int position) { Boolean result = mSelection.get(position); return result == null ? false : result; } public Set<Integer> getCurrentCheckedPosition() { return mSelection.keySet(); } public void removeSelection(int position) { mSelection.remove(position); notifyDataSetChanged(); } public void clearSelection() { mSelection.clear(); notifyDataSetChanged(); } @Override public View getView(int position, View convertView, ViewGroup parent) { // let the adapter handle setting up the row views View v = super.getView(position, convertView, parent); /** * Change color for multi-selection */ // default color v.setBackgroundColor(Color.TRANSPARENT); if (mSelection.get(position) != null && mSelection.get(position).booleanValue()) { // this is a selected position, change color! v.setBackgroundColor(parent.getResources().getColor(R.color.emphasis)); } return v; } }