// @author Bhavya Mehta package com.marshalchen.common.demoofui.listviewfilter.ui; import java.util.ArrayList; import java.util.Arrays; import java.util.Collections; import java.util.Locale; import android.app.Activity; import android.app.IntentService; import android.content.BroadcastReceiver; import android.content.Context; import android.content.Intent; import android.content.IntentFilter; import android.os.Bundle; import android.support.v4.content.LocalBroadcastManager; import android.text.Editable; import android.text.TextWatcher; import android.view.LayoutInflater; import android.view.View; import android.widget.EditText; import android.widget.Filter; import android.widget.ProgressBar; import android.widget.TextView; import com.marshalchen.common.demoofui.R; import com.marshalchen.common.demoofui.listviewfilter.PinnedHeaderAdapter; // Activity that display customized list view and search box public class ListViewFilterActivity extends Activity { private static final String POPULATE_FILTER = "ListViewFilterActivity_populateReceiver"; // an array of countries to display in the list static final String[] ITEMS = new String[]{"张三", "李四", "East Timor", "Ecuador", "Egypt", "El Salvador", "Equatorial Guinea", "Eritrea", "Estonia", "Ethiopia", "Faeroe Islands", "Falkland Islands", "Fiji", "Finland", "Afghanistan", "Albania", "Algeria", "American Samoa", "Andorra", "Angola", "Anguilla", "Antarctica", "Antigua and Barbuda", "Argentina", "Armenia", "Aruba", "Australia", "Austria", "Azerbaijan", "Bahrain", "Bangladesh", "Barbados", "Belarus", "Belgium", "Monaco", "Mongolia", "Montserrat", "Morocco", "Mozambique", "Myanmar", "Namibia", "Nauru", "Nepal", "Netherlands", "Netherlands Antilles", "New Caledonia", "New Zealand", "Guyana", "Haiti", "Heard Island and McDonald Islands", "Honduras", "Hong Kong", "Hungary", "Iceland", "India", "Indonesia", "Iran", "Iraq", "Ireland", "Israel", "Italy", "Jamaica", "Japan", "Jordan", "Kazakhstan", "Kenya", "Kiribati", "Kuwait", "Kyrgyzstan", "Laos", "Latvia", "Lebanon", "Lesotho", "Liberia", "Libya", "Liechtenstein", "Lithuania", "Luxembourg", "Nicaragua", "Niger", "Nigeria", "Niue", "Norfolk Island", "North Korea", "Northern Marianas", "Norway", "Oman", "Pakistan", "Palau", "Panama", "Papua New Guinea", "Paraguay", "Peru", "Philippines", "Pitcairn Islands", "Poland", "Portugal", "Puerto Rico", "Qatar", "French Southern Territories", "Gabon", "Georgia", "Germany", "Ghana", "Gibraltar", "Greece", "Greenland", "Grenada", "Guadeloupe", "Guam", "Guatemala", "Guinea", "Guinea-Bissau", "Martinique", "Mauritania", "Mauritius", "Mayotte", "Mexico", "Micronesia", "Moldova", "Bosnia and Herzegovina", "Botswana", "Bouvet Island", "Brazil", "British Indian Ocean Territory", "Saint Vincent and the Grenadines", "Samoa", "San Marino", "Saudi Arabia", "Senegal", "Seychelles", "Sierra Leone", "Singapore", "Slovakia", "Slovenia", "Solomon Islands", "Somalia", "South Africa", "South Georgia and the South Sandwich Islands", "South Korea", "Spain", "Sri Lanka", "Sudan", "Suriname", "Svalbard and Jan Mayen", "Swaziland", "Sweden", "Switzerland", "Syria", "Taiwan", "Tajikistan", "Tanzania", "Thailand", "The Bahamas", "The Gambia", "Togo", "Tokelau", "Tonga", "Trinidad and Tobago", "Tunisia", "Turkey", "Turkmenistan", "Turks and Caicos Islands", "Tuvalu", "Uganda", "Ukraine", "United Arab Emirates", "United Kingdom", "United States", "United States Minor Outlying Islands", "Uruguay", "Uzbekistan", "Vanuatu", "Vatican City", "Venezuela", "Vietnam", "Virgin Islands", "Wallis and Futuna", "Western Sahara", "British Virgin Islands", "Brunei", "Bulgaria", "Burkina Faso", "Burundi", "Cote d'Ivoire", "Cambodia", "Cameroon", "Canada", "Cape Verde", "Cayman Islands", "Central African Republic", "Chad", "Chile", "China", "Reunion", "Romania", "Russia", "Rwanda", "Sqo Tome and Principe", "Saint Helena", "Saint Kitts and Nevis", "Saint Lucia", "Saint Pierre and Miquelon", "Belize", "Benin", "Bermuda", "Bhutan", "Bolivia", "Christmas Island", "Cocos (Keeling) Islands", "Colombia", "Comoros", "Congo", "Cook Islands", "Costa Rica", "Croatia", "Cuba", "Cyprus", "Czech Republic", "Democratic Republic of the Congo", "Denmark", "Djibouti", "Dominica", "Dominican Republic", "Former Yugoslav Republic of Macedonia", "France", "French Guiana", "French Polynesia", "Macau", "Madagascar", "Malawi", "Malaysia", "Maldives", "Mali", "Malta", "Marshall Islands", "Yemen", "Yugoslavia", "Zambia", "Zimbabwe"}; // unsorted list items ArrayList<String> mItems; // array list to store section positions ArrayList<Integer> mListSectionPos; // array list to store listView data ArrayList<String> mListItems; // custom list view with pinned header PinnedHeaderListView mListView; // custom adapter PinnedHeaderAdapter mAdaptor; // search box EditText mSearchView; // loading view ProgressBar mLoadingView; // empty view TextView mEmptyView; PoplulateReceiver populateReceiver; @SuppressWarnings("unchecked") @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); // UI elements setupViews(); // Array to ArrayList mItems = new ArrayList<String>(Arrays.asList(ITEMS)); mListSectionPos = new ArrayList<Integer>(); mListItems = new ArrayList<String>(); populateReceiver = new PoplulateReceiver(); LocalBroadcastManager.getInstance(this) .registerReceiver(populateReceiver, new IntentFilter(POPULATE_FILTER)); // for handling configuration change if (savedInstanceState != null) { mListItems = savedInstanceState.getStringArrayList("mListItems"); mListSectionPos = savedInstanceState.getIntegerArrayList("mListSectionPos"); if (mListItems != null && mListItems.size() > 0 && mListSectionPos != null && mListSectionPos.size() > 0) { setListAdaptor(); } String constraint = savedInstanceState.getString("constraint"); if (constraint != null && constraint.length() > 0) { mSearchView.setText(constraint); setIndexBarViewVisibility(constraint); } } else { Intent populate = new Intent(this, PopulateService.class); populateReceiver.showLoading(); populate.putExtra("mListSectionPos", mListSectionPos); populate.putExtra("mListItems", mListItems); populate.putExtra("mItems", mItems); populate.putExtra("params", mItems); this.startService(populate); } } @Override public void onDestroy() { super.onDestroy(); if (populateReceiver != null) LocalBroadcastManager.getInstance(this).unregisterReceiver(populateReceiver); } private void setupViews() { setContentView(R.layout.list_filter_main_act); mSearchView = (EditText) findViewById(R.id.search_view); mLoadingView = (ProgressBar) findViewById(R.id.loading_view); mListView = (PinnedHeaderListView) findViewById(R.id.list_view); mEmptyView = (TextView) findViewById(R.id.empty_view); } // I encountered an interesting problem with a TextWatcher listening for // changes in an EditText. // The afterTextChanged method was called, each time, the device orientation // changed. // An answer on Stackoverflow let me understand what was happening: Android // recreates the activity, and // the automatic restoration of the state of the input fields, is happening // after onCreate had finished, // where the TextWatcher was added as a TextChangedListener.The solution to // the problem consisted in adding // the TextWatcher in onPostCreate, which is called after restoration has // taken place // // http://stackoverflow.com/questions/6028218/android-retain-callback-state-after-configuration-change/6029070#6029070 // http://stackoverflow.com/questions/5151095/textwatcher-called-even-if-text-is-set-before-adding-the-watcher @Override protected void onPostCreate(Bundle savedInstanceState) { mSearchView.addTextChangedListener(filterTextWatcher); super.onPostCreate(savedInstanceState); } private void setListAdaptor() { // create instance of PinnedHeaderAdapter and set adapter to list view mAdaptor = new PinnedHeaderAdapter(this, mListItems, mListSectionPos); mListView.setAdapter(mAdaptor); LayoutInflater inflater = (LayoutInflater) getSystemService(LAYOUT_INFLATER_SERVICE); // set header view View pinnedHeaderView = inflater.inflate(R.layout.list_filter_section_row_view, mListView, false); mListView.setPinnedHeaderView(pinnedHeaderView); // set index bar view IndexBarView indexBarView = (IndexBarView) inflater.inflate(R.layout.list_filter_index_bar_view, mListView, false); indexBarView.setData(mListView, mListItems, mListSectionPos); mListView.setIndexBarView(indexBarView); // set preview text view View previewTextView = inflater.inflate(R.layout.list_filter_preview_view, mListView, false); mListView.setPreviewView(previewTextView); // for configure pinned header view on scroll change mListView.setOnScrollListener(mAdaptor); } private TextWatcher filterTextWatcher = new TextWatcher() { public void afterTextChanged(Editable s) { String str = s.toString(); if (mAdaptor != null && str != null) mAdaptor.getFilter().filter(str); } public void beforeTextChanged(CharSequence s, int start, int count, int after) { } public void onTextChanged(CharSequence s, int start, int before, int count) { } }; public class ListFilter extends Filter { @Override protected FilterResults performFiltering(CharSequence constraint) { // NOTE: this function is *always* called from a background thread, // and // not the UI thread. String constraintStr = constraint.toString().toLowerCase(Locale.getDefault()); FilterResults result = new FilterResults(); if (constraint != null && constraint.toString().length() > 0) { ArrayList<String> filterItems = new ArrayList<String>(); synchronized (this) { for (int i = 0; i < mItems.size(); i++) { String item = mItems.get(i); if (item.toLowerCase(Locale.getDefault()).startsWith(constraintStr)) { filterItems.add(item); } } result.count = filterItems.size(); result.values = filterItems; } } else { synchronized (this) { result.count = mItems.size(); result.values = mItems; } } return result; } @Override protected void publishResults(CharSequence constraint, FilterResults results) { ArrayList<String> filtered = (ArrayList<String>) results.values; setIndexBarViewVisibility(constraint.toString()); // sort array and extract sections in background Thread Intent populate = new Intent(ListViewFilterActivity.this, PopulateService.class); populateReceiver.showLoading(); populate.putExtra("mListSectionPos", mListSectionPos); populate.putExtra("mListItems", mListItems); populate.putExtra("mItems", mItems); populate.putExtra("params", filtered); ListViewFilterActivity.this.startService(populate); } } private void setIndexBarViewVisibility(String constraint) { // hide index bar for search results if (constraint != null && constraint.length() > 0) { mListView.setIndexBarVisibility(false); } else { mListView.setIndexBarVisibility(true); } } private class PoplulateReceiver extends BroadcastReceiver { private void showLoading(View contentView, View loadingView, View emptyView) { contentView.setVisibility(View.GONE); loadingView.setVisibility(View.VISIBLE); emptyView.setVisibility(View.GONE); } private void showContent(View contentView, View loadingView, View emptyView) { contentView.setVisibility(View.VISIBLE); loadingView.setVisibility(View.GONE); emptyView.setVisibility(View.GONE); } private void showEmptyText(View contentView, View loadingView, View emptyView) { contentView.setVisibility(View.GONE); loadingView.setVisibility(View.GONE); emptyView.setVisibility(View.VISIBLE); } protected void showLoading() { // show loading indicator showLoading(mListView, mLoadingView, mEmptyView); } @Override public void onReceive(Context receiverContext, Intent receiverIntent) { mListItems = receiverIntent.getStringArrayListExtra("mListItems"); mListSectionPos = receiverIntent.getIntegerArrayListExtra("mListSectionPos"); if (mListItems.size() <= 0) { showEmptyText(mListView, mLoadingView, mEmptyView); } else { setListAdaptor(); showContent(mListView, mLoadingView, mEmptyView); } } } // sort array and extract sections in background Thread here we use // IntentService public static class PopulateService extends IntentService { ArrayList<Integer> mListSectionPos; ArrayList<String> mListItems; ArrayList<String> mItems; public PopulateService() { super("PopulateService"); } public void onHandleIntent(Intent intent) { this.mListSectionPos = intent.getIntegerArrayListExtra("mListSectionPos"); this.mListItems = intent.getStringArrayListExtra("mListItems"); this.mItems = intent.getStringArrayListExtra("mItems"); ArrayList<String> params = intent.getStringArrayListExtra("params"); mListItems.clear(); mListSectionPos.clear(); ArrayList<String> items = params; if (mItems.size() > 0) { // NOT forget to sort array Collections.sort(items); int i = 0; String prev_section = ""; while (i < items.size()) { String current_item = items.get(i).toString(); String current_section = current_item.substring(0, 1).toUpperCase(Locale.getDefault()); if (!prev_section.equals(current_section)) { mListItems.add(current_section); mListItems.add(current_item); // array list of section positions mListSectionPos.add(mListItems.indexOf(current_section)); prev_section = current_section; } else { mListItems.add(current_item); } i++; } } Intent resultIntent = new Intent(POPULATE_FILTER); resultIntent.putExtra("mListItems", mListItems); resultIntent.putExtra("mListSectionPos", mListSectionPos); LocalBroadcastManager.getInstance(this).sendBroadcast(resultIntent); } } @Override protected void onSaveInstanceState(Bundle outState) { if (mListItems != null && mListItems.size() > 0) { outState.putStringArrayList("mListItems", mListItems); } if (mListSectionPos != null && mListSectionPos.size() > 0) { outState.putIntegerArrayList("mListSectionPos", mListSectionPos); } String searchText = mSearchView.getText().toString(); if (searchText != null && searchText.length() > 0) { outState.putString("constraint", searchText); } super.onSaveInstanceState(outState); } }