Develop Reference

CefSharp Javascript registration and execution is not working in Release 79.1.36

I tried to upgrade CefSharp from Version 69.0.0.0 to 79.1.36.
I could not get the Javascript interaction working.
The registration changed from
this.Browser.RegisterJsObject
to
this.Browser.JavascriptObjectRepository.Register
according to https://github.com/cefsharp/CefSharp/issues/2990.
When I execute EvaluateScriptAsync, I get a response back with Status Canceled.
Trying to understand how to implement it correctly, I examined the CefSharp.WpfExample and noticed that the Javascript functionality in the example WPF application does not work either.
The Execute Javascript (asynchronously) does not do anything when clicking the Run button.
The Evaluate Javascript (Async) returns:
Uncaught ReferenceError: bound is not defined # about:blank:1:0
Did the Javascript functionality break in the latest release?
Update
Here is how it is used in our code.
This is the registration
public void RegisterJavaScriptHandler(string name, object handler)
{
try
{
CefSharpSettings.LegacyJavascriptBindingEnabled = true;
this.Browser.JavascriptObjectRepository.Register(name, handler, false, new BindingOptions() { CamelCaseJavascriptNames = false });
}
catch (Exception ex)
{
Console.WriteLine(ex);
}
}
This is the EvaluateScriptAsync part
public void InitializeLayers()
{
try
{
int count = _mapLogic.Layers.Count();
foreach (WMSLayer layer in _mapLogic.Layers)
{
if (!_loadedLayers.Contains(layer))
{
var script = string.Format("addWMSLayer('{0}', '{1}', '{2}', '{3}', '{4}', '{5}', '{6}', '{7}', '{8}', '{9}')",
layer.ProviderCode.Url, layer.AttributionText, layer.AttributionHref,
layer.Layer, layer.FormatCode.Format, layer.ServerType, layer.Res1, layer.Res2, layer.Res3, layer.Res4);
var response = this.ECBBrowser.Browser.EvaluateScriptAsync(script, new TimeSpan(0, 0, 1));
response.ContinueWith(t =>
{
count--;
if (count == 0) this.initializeMap();
});
_loadedLayers.Add(layer);
}
else
{
count--;
if(count == 0) this.initializeMap();
}
}
}
catch (Exception ex)
{
Console.WriteLine(ex);
}
}
Update II
I now believe something has changed with the resource loading.
This is what I have (unimportant parts are left out).
public class ECBSchemeHandler : IResourceHandler
{
private string _mimeType;
private Stream _stream;
public bool Open(IRequest request, out bool handleRequest, ICallback callback)
{
var result = open(request, callback);
handleRequest = result;
return result;
}
public bool Read(Stream dataOut, out int bytesRead, IResourceReadCallback callback)
{
return read(dataOut, out bytesRead, callback);
}
public bool ReadResponse(Stream dataOut, out int bytesRead, ICallback callback)
{
return read(dataOut, out bytesRead, callback);
}
private bool open(IRequest request, ICallback callback)
{
var u = new Uri(request.Url);
var file = u.Authority + u.AbsolutePath;
var ass = Assembly.GetExecutingAssembly();
var resourcePath = ECBConfiguration.DEFAULT_ASSEMBLY_NAMESPACE + "." + file.Replace("/", ".");
if (ass.GetManifestResourceInfo(resourcePath) != null)
{
Task.Run(() =>
{
using (callback)
{
_stream = ass.GetManifestResourceStream(resourcePath);
var fileExtension = Path.GetExtension(file);
_mimeType = ResourceHandler.GetMimeType(fileExtension);
callback.Continue();
}
});
return true;
}
else
{
callback.Dispose();
}
return false;
}
private bool read(Stream dataOut, out int bytesRead, IDisposable callback)
{
callback.Dispose();
if (_stream == null)
{
bytesRead = 0;
return false;
}
//Data out represents an underlying buffer (typically 32kb in size).
var buffer = new byte[dataOut.Length];
bytesRead = _stream.Read(buffer, 0, buffer.Length);
dataOut.Write(buffer, 0, buffer.Length);
return bytesRead > 0;
}
}
}

Using the built-in ResourceHandlers as pointed out by #amaitland solved the problem with the Javascript registration.

How to display a enum value using a user-entered int?

I need to do 3 things with the CardsDriver: using the default constructor Card() display a default card. Then, take a user's int and display a Card object using the parameterized constructor Card(int n) (Using mod%). Finally use showDeck() to display all 52 cards. (As you can tell I kinda did this using the enhanced for loops at the end, it works but I do not think it is the best way.)
Would really like some help with at least the second problem. I just need to understand what I need to implement..
package cards;
import java.util.Scanner;
public class CardsDriver
{
private static Scanner keyboard = new Scanner(System.in);
public static void main (String[] args)
{
boolean another;
int n;
Card card = new Card();
do
{
System.out.println("Type a non-negative integer. Type -1 to
stop.");
n = keyboard.nextInt( );
if (n == -1)
{
another = false;
}
else
{
another = true;
}
} while (another == true);
System.out.println("All 52 Cards Follow:");
showDeck( );
}
private static int getNextInt()
{
return keyboard.nextInt();
}
private static void showDeck()
{
for (Face face : Face.values())
{
for (Suit suit : Suit.values())
System.out.println("The " + face + " of " + suit);
}
}
}
and here is my Card class
package cards;
public class Card {
private Face face;
private Suit suit;
public Card() {
face = Face.ACE;
suit = Suit.CLUBS;
}
public Card(Card existingCard) {
this.face = existingCard.face;
this.suit = existingCard.suit;
}
public Card(int n) {
face = Face.values()[n % 13];
suit = Suit.values()[n % 4];
}
public String toString() {
return "the" + face + "of" + suit;
}
}

Remember Me button in android app

I have recently created a new plugin for an android app I've been working on. This plugin requires the use of a remember me function that I cant seem to get working properly. Within my code I've designated the use of shared properties at the top and the string pass.
View thisScreensView = null;
String errormessage = "";
String errormessageTextColor = "";
String errormessageText = "";
String rememberTextText = "";
String rememberTextTextColor = "";
String voucherTextfieldPlaceholder = "";
String voucherTextfieldSecureTextEntry = "";
boolean voucherTextfieldSecureTextEntryBool = false;
String iphoneImage = "";
String ipadImage = "";
String errormessageInvalid = "";
String errormessageRemember = "";
private TextView errormessageTextView = null;
private EditText voucherTextfieldEditText = null;
private ImageView imageView = null;
private Button submitButton = null;
private Switch rememberSwitch = null;
private Drawable myHeaderImageDrawable = null;
private String alphaImage = "", pass;
private static BT_item screenObjectToLoad = null;
SharedPreferences sharedpreferences;
I have it assigning the variable pass into the designated text box with this code:
voucherTextfieldEditText.setVisibility(View.VISIBLE);
rememberSwitch = (Switch) thisScreensView.findViewById(R.id.rememberSwitch);
// set the switch to ON
rememberSwitch.setText(errormessageRemember);
rememberSwitch.setChecked(true);
// attach a listener to check for changes in state
rememberSwitch.setOnCheckedChangeListener(new OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (isChecked) {
BT_debugger.showIt(fragmentName + ":rememberSwitch is ON");
// switchStatus.setText("Switch is currently ON");
//voucherTextfieldEditText.setText(pref.getString(pass, null));
} else {
BT_debugger.showIt(fragmentName + ":rememberSwitch is OFF");
// switchStatus.setText("Switch is currently OFF");
}
}
});
// check the current state before we display the screen
if (rememberSwitch.isChecked()) {
BT_debugger.showIt(fragmentName + ":rememberSwitch is ON");
// switchStatus.setText("Switch is currently ON");
//voucherTextfieldEditText.setText(pass);
if (voucherTextfieldEditText!=null) {
//voucherTextfieldEditText.setText(sharedPreferences.getString(pass, ""));
}
if (pass != null) {
String textfield = sharedpreferences.getString("PASS", pass);
//voucherTextfieldEditText.setText(sharedPreferences.getString("PASS", pass));
voucherTextfieldEditText.setText(textfield);
}
}
else {
BT_debugger.showIt(fragmentName + ":rememberSwitch is OFF");
// switchStatus.setText("Switch is currently OFF");
}
//
// submit click listener..
submitButton = (Button) thisScreensView.findViewById(R.id.submitButtonVoucher);
submitButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
launchScreen(voucherTextfieldEditText.getText().toString());
}
});
// return the layout file as the view for this screen..
return thisScreensView;
}// onCreateView...
Then I set the shared preferences string "PASS" with this line of code:
if (loadScreenNickname.length() > 1 && !loadScreenNickname.equalsIgnoreCase("none")) {
// before we launch the next screen...
if (!rememberSwitch.isChecked()) {
voucherTextfieldEditText.setText("");
}
if (rememberSwitch.isChecked()){
//voucherTextfieldEditText.setText("");
//editor.putString(pass, voucherTextfieldEditText.getText().toString().trim());
//editor.apply();
pass = voucherTextfieldEditText.getText().toString();
SharedPreferences.Editor editor = sharedpreferences.edit();
editor.putString("PASS", pass);
editor.apply();
}
errormessageTextView.setVisibility(View.GONE);
errormessageTextView.invalidate();
//loadScreenObject(null, thisScreen);
try {
loadScreenWithNickname(loadScreenNickname);
foundIt = 1;
} catch (Exception ex){
Log.e ("eTutorPrism Error", "Caught this exception " + ex);
ex.printStackTrace();
}
break;
}
}
However anything I exit and restart the application, even if the remember me button is checked, it doesn't remember the previous value and the app ends up crashing due to a null. Everything else in the code works except the Remember Me. If anyones got any ideas I could use them?

You are not initializing your sharedPreference. try to initialize it.
SharedPreferences sharedPreferences=getSharedPreferences("myPref",MODE_PRIVATE);

Google's Text-To-Speech API from Android app

I want to use Google's Text-To-Speech API in an Android app but I only could find the way to do it from web (Chrome). This is my first attempt to play "Hello world" from the app.
playTTS is the onClick and it is been executed, but no sound is played. Is there any JS/Java library I need to import? Is it possible to generate an audio file from it?
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myBrowser = new WebView(this);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment()).commit();
}
}
public void playTTS(View view) {
myBrowser.loadUrl("javascript:speechSynthesis.speak(
SpeechSynthesisUtterance('Hello World'))");
}

In Android java code your Activity/other Class should implement TextToSpeech.OnInitListener. You will get a TextToSpeech instance by calling TextToSpeech(context, this). (Where context refers to your application's Context -- can be this in an Activity.) You will then receive a onInit() callback with status which tells whether the TTS engine is available or not.
You can talk by calling tts.speak(textToBeSpoken, TextToSpeech.QUEUE_FLUSH, null) or tts.speak(textToBeSpoken, TextToSpeech.QUEUE_ADD, null). The first one will interrupt any "utterance" that is still being spoken and the latter one will add the new "utterance" to a queue. The last parameter is not mandatory. It could be an "utterance id" defined by you in case you want to monitor the TTS status by setting an UtteranceProgressListener. (Not necessary)
In Java code a simple "TTS talker" class could be something like:
public class MyTtsTalker implements TextToSpeech.OnInitListener {
private TextToSpeech tts;
private boolean ttsOk;
// The constructor will create a TextToSpeech instance.
MyTtsTalker(Context context) {
tts = new TextToSpeech(context, this);
}
#Override
// OnInitListener method to receive the TTS engine status
public void onInit(int status) {
if (status == TextToSpeech.SUCCESS) {
ttsOk = true;
}
else {
ttsOk = false;
}
}
// A method to speak something
#SuppressWarnings("deprecation") // Support older API levels too.
public void speak(String text, Boolean override) {
if (ttsOk) {
if (override) {
tts.speak(text, TextToSpeech.QUEUE_FLUSH, null);
}
else {
tts.speak(text, TextToSpeech.QUEUE_ADD, null);
}
}
}
}

Code for TTS:
import android.annotation.TargetApi;
import android.content.Context;
import android.os.Build;
import android.speech.tts.TextToSpeech;
import android.speech.tts.UtteranceProgressListener;
import android.util.Log;
import android.webkit.JavascriptInterface;
import android.webkit.WebView;
import android.widget.Toast;
import java.util.HashMap;
import java.util.Locale;
public class KiwixTextToSpeech {
public static final String TAG_ASKQ = "askq;
private Context context;
private OnSpeakingListener onSpeakingListener;
private WebView webView;
private TextToSpeech tts;
private boolean initialized = false;
/**
* Constructor.
*
* #param context the context to create TextToSpeech with
* #param webView {#link android.webkit.WebView} to take contents from
* #param onInitSucceedListener listener that receives event when initialization of TTS is done
* (and does not receive if it failed)
* #param onSpeakingListener listener that receives an event when speaking just started or
* ended
*/
public KiwixTextToSpeech(Context context, WebView webView,
final OnInitSucceedListener onInitSucceedListener,
final OnSpeakingListener onSpeakingListener) {
Log.d(TAG_ASKQ, "Initializing TextToSpeech");
this.context = context;
this.onSpeakingListener = onSpeakingListener;
this.webView = webView;
this.webView.addJavascriptInterface(new TTSJavaScriptInterface(), "tts");
initTTS(onInitSucceedListener);
}
#TargetApi(Build.VERSION_CODES.ICE_CREAM_SANDWICH_MR1)
private void initTTS(final OnInitSucceedListener onInitSucceedListener) {
tts = new TextToSpeech(context, new TextToSpeech.OnInitListener() {
#Override
public void onInit(int status) {
if (status == TextToSpeech.SUCCESS) {
Log.d(TAG_ASKQ, "TextToSpeech was initialized successfully.");
initialized = true;
onInitSucceedListener.onInitSucceed();
} else {
Log.e(TAG_ASKQ, "Initilization of TextToSpeech Failed!");
}
}
});
tts.setOnUtteranceProgressListener(new UtteranceProgressListener() {
#Override
public void onStart(String utteranceId) {
}
#Override
public void onDone(String utteranceId) {
Log.e(TAG_ASKQ, "TextToSpeech: " + utteranceId);
onSpeakingListener.onSpeakingEnded();
}
#Override
public void onError(String utteranceId) {
Log.e(TAG_ASKQ, "TextToSpeech: " + utteranceId);
onSpeakingListener.onSpeakingEnded();
}
});
}
/**
* Reads the currently selected text in the WebView.
*/
public void readSelection() {
webView.loadUrl("javascript:tts.speakAloud(window.getSelection().toString());", null);
}
/**
* Starts speaking the WebView content aloud (or stops it if TTS is speaking now).
*/
public void readAloud() {
if (tts.isSpeaking()) {
if (tts.stop() == TextToSpeech.SUCCESS) {
onSpeakingListener.onSpeakingEnded();
}
} else {
Locale locale = LanguageUtils.ISO3ToLocale(ZimContentProvider.getLanguage());
int result;
if (locale == null
|| (result = tts.isLanguageAvailable(locale)) == TextToSpeech.LANG_MISSING_DATA
|| result == TextToSpeech.LANG_NOT_SUPPORTED) {
Log.d(TAG_ASKQ, "TextToSpeech: language not supported: " +
ZimContentProvider.getLanguage() + " (" + locale.getLanguage() + ")");
Toast.makeText(context,
context.getResources().getString(R.string.tts_lang_not_supported),
Toast.LENGTH_LONG).show();
} else {
tts.setLanguage(locale);
// We use JavaScript to get the content of the page conveniently, earlier making some
// changes in the page
webView.loadUrl("javascript:" +
"body = document.getElementsByTagName('body')[0].cloneNode(true);" +
// Remove some elements that are shouldn't be read (table of contents,
// references numbers, thumbnail captions, duplicated title, etc.)
"toRemove = body.querySelectorAll('sup.reference, #toc, .thumbcaption, " +
" title, .navbox');" +
"Array.prototype.forEach.call(toRemove, function(elem) {" +
" elem.parentElement.removeChild(elem);" +
"});" +
"tts.speakAloud(body.innerText);");
}
}
}
/**
* Returns whether the TTS is initialized.
*
* #return <code>true</code> if TTS is initialized; <code>false</code> otherwise
*/
public boolean isInitialized() {
return initialized;
}
/**
* Releases the resources used by the engine.
*
* #see android.speech.tts.TextToSpeech#shutdown()
*/
public void shutdown() {
tts.shutdown();
}
/**
* The listener which is notified when initialization of the TextToSpeech engine is successfully
* done.
*/
public interface OnInitSucceedListener {
public void onInitSucceed();
}
/**
* The listener that is notified when speaking starts or stops (regardless of whether it was a
* result of error, user, or because whole text was read).
*
* Note that the methods of this interface may not be called from the UI thread.
*/
public interface OnSpeakingListener {
public void onSpeakingStarted();
public void onSpeakingEnded();
}
private class TTSJavaScriptInterface {
#JavascriptInterface
#SuppressWarnings("unused")
public void speakAloud(String content) {
String[] lines = content.split("\n");
for (int i = 0; i < lines.length - 1; i++) {
String line = lines[i];
tts.speak(line, TextToSpeech.QUEUE_ADD, null);
}
HashMap<String, String> params = new HashMap<>();
// The utterance ID isn't actually used anywhere, the param is passed only to force
// the utterance listener to be notified
params.put(TextToSpeech.Engine.KEY_PARAM_UTTERANCE_ID, "kiwixLastMessage");
tts.speak(lines[lines.length - 1], TextToSpeech.QUEUE_ADD, params);
if (lines.length > 0) {
onSpeakingListener.onSpeakingStarted();
}
}
}
}

How to create dependant dropndown/selection cell In GWT celltable 2.3?

I am using gwt2.3 celltable.
In my celltable there will be multiple column out of that few columns are dependent.
ex. Name and address columns are dependent
Name and address columns contains my custom selection cells.
In Name column : 1 cell contains jon,tom,steve
when Name cell contains jon then I want to set US & UK in address cell
if user changes Name cell to tom then I want to set india & china in address cell
if user changes Name cell to steve then I want to set japana & bhutan in address cell
I want to change dependent data from address cell when name cells selection changes.
How I can achieve this thing? Any sample code or pointers to do this?

This solution is for GWT 2.5, but it should probably work in 2.3.
I think the best is that you modify your RecordInfo element when you change the selection on the first column. You can do it similar to this in your CustomSelectionCell:
#Override
public void onBrowserEvent(Context context, Element parent, C value, NativeEvent event, ValueUpdater<C> valueUpdater) {
super.onBrowserEvent(context, parent, value, event, valueUpdater);
if (BrowserEvents.CHANGE.equals(event.getType())) {
Xxxxx newValue = getSelectedValueXxxxx();
valueUpdater.update(newValue);
}
}
Then where you use your cell add a fieldUpdater like this, that will update the RecordInfo with the new value and ask to redraw the row:
column.setFieldUpdater(new FieldUpdater<.....>() {
....
recordInfo.setXxxxx(newValue);
cellTable.redrawRow(index);
....
});
This will call the render of the other CustomSelectionCell, in there you will be able to check if the value of the RecordInfo has changed and update the seletion values as needed. Example:
#Override
public void render(Context context, C value, SafeHtmlBuilder sb) {
if (!value.getXxxxx().equals(this.lastValue)) {
this.items = loadItemsForValueXxxx(value.getXxxxx());
}
.... // Your usual render.
}
Be careful when you changed the items to set a default selected item too.

This is my implementation of DynamicSelectionCell.
DynamicSelectionCell allows you to render different options for different rows in the same GWT table.
Use a single DynamicSelectionCell object and use the addOption method to add options for each row. Options are stored in a Map with the Key being the row number.
For each row $i in the table the options stored in the Map for key $i are rendered.
Works on DataGrid, CellTable.
CODE
public class DynamicSelectionCell extends AbstractInputCell<String, String> {
public TreeMap<Integer, List<String>> optionsMap = new TreeMap<Integer, List<String>>();
interface Template extends SafeHtmlTemplates {
#Template("<option value=\"{0}\">{0}</option>")
SafeHtml deselected(String option);
#Template("<option value=\"{0}\" selected=\"selected\">{0}</option>")
SafeHtml selected(String option);
}
private static Template template;
private TreeMap<Integer, HashMap<String, Integer>> indexForOption = new TreeMap<Integer, HashMap<String, Integer>>();
/**
* Construct a new {#link SelectionCell} with the specified options.
*
* #param options the options in the cell
*/
public DynamicSelectionCell() {
super("change");
if (template == null) {
template = GWT.create(Template.class);
}
}
public void addOption(List<String> newOps, int key){
optionsMap.put(key, newOps);
HashMap<String, Integer> localIndexForOption = new HashMap<String, Integer>();
indexForOption.put(ind, localIndexForOption);
refreshIndexes();
}
public void removeOption(int index){
optionsMap.remove(index);
refreshIndexes();
}
private void refreshIndexes(){
int ind=0;
for (List<String> options : optionsMap.values()){
HashMap<String, Integer> localIndexForOption = new HashMap<String, Integer>();
indexForOption.put(ind, localIndexForOption);
int index = 0;
for (String option : options) {
localIndexForOption.put(option, index++);
}
ind++;
}
}
#Override
public void onBrowserEvent(Context context, Element parent, String value,
NativeEvent event, ValueUpdater<String> valueUpdater) {
super.onBrowserEvent(context, parent, value, event, valueUpdater);
String type = event.getType();
if ("change".equals(type)) {
Object key = context.getKey();
SelectElement select = parent.getFirstChild().cast();
String newValue = optionsMap.get(context.getIndex()).get(select.getSelectedIndex());
setViewData(key, newValue);
finishEditing(parent, newValue, key, valueUpdater);
if (valueUpdater != null) {
valueUpdater.update(newValue);
}
}
}
#Override
public void render(Context context, String value, SafeHtmlBuilder sb) {
// Get the view data.
Object key = context.getKey();
String viewData = getViewData(key);
if (viewData != null && viewData.equals(value)) {
clearViewData(key);
viewData = null;
}
int selectedIndex = getSelectedIndex(viewData == null ? value : viewData, context.getIndex());
sb.appendHtmlConstant("<select tabindex=\"-1\">");
int index = 0;
try{
for (String option : optionsMap.get(context.getIndex())) {
if (index++ == selectedIndex) {
sb.append(template.selected(option));
} else {
sb.append(template.deselected(option));
}
}
}catch(Exception e){
System.out.println("error");
}
sb.appendHtmlConstant("</select>");
}
private int getSelectedIndex(String value, int ind) {
Integer index = indexForOption.get(ind).get(value);
if (index == null) {
return -1;
}
return index.intValue();
}
}

Varun Tulsian's answer is very good, but the code is incomplete.
The DynamicSelectionCell stores each rows' options in a map. When the cell updates or renders itself, it matches the row index from your Context to its matching row list in your map.
For posterity, see the simplified and updated version below:
public class DynamicSelectionCell extends AbstractInputCell<String, String> {
interface Template extends SafeHtmlTemplates {
#Template("<option value=\"{0}\">{0}</option>")
SafeHtml deselected(String option);
#Template("<option value=\"{0}\" selected=\"selected\">{0}</option>")
SafeHtml selected(String option);
}
private static Template template;
/**
* key: rowIndex
* value: List of options to show for this row
*/
public TreeMap<Integer, List<String>> optionsMap = new TreeMap<Integer, List<String>>();
/**
* Construct a new {#link SelectionCell} with the specified options.
*
*/
public DynamicSelectionCell() {
super("change");
if (template == null) {
template = GWT.create(Template.class);
}
}
public void addOptions(List<String> newOps, int rowIndex) {
optionsMap.put(rowIndex, newOps);
}
public void removeOptions(int rowIndex) {
optionsMap.remove(rowIndex);
}
#Override
public void onBrowserEvent(Context context, Element parent, String value,
NativeEvent event, ValueUpdater<String> valueUpdater) {
super.onBrowserEvent(context, parent, value, event, valueUpdater);
String type = event.getType();
if ("change".equals(type)) {
Object key = context.getKey();
SelectElement select = parent.getFirstChild().cast();
String newValue = optionsMap.get(context.getIndex()).get(select.getSelectedIndex());
setViewData(key, newValue);
finishEditing(parent, newValue, key, valueUpdater);
if (valueUpdater != null) {
valueUpdater.update(newValue);
}
}
}
#Override
public void render(Context context, String value, SafeHtmlBuilder sb) {
// Get the view data.
Object key = context.getKey();
String viewData = getViewData(key);
if (viewData != null && viewData.equals(value)) {
clearViewData(key);
viewData = null;
}
int selectedIndex = getSelectedIndex(viewData == null ? value : viewData, context.getIndex());
sb.appendHtmlConstant("<select tabindex=\"-1\">");
int index = 0;
try {
for (String option : optionsMap.get(context.getIndex())) {
if (index++ == selectedIndex) {
sb.append(template.selected(option));
} else {
sb.append(template.deselected(option));
}
}
} catch (Exception e) {
System.out.println("error");
}
sb.appendHtmlConstant("</select>");
}
private int getSelectedIndex(String value, int rowIndex) {
if (optionsMap.get(rowIndex) == null) {
return -1;
}
return optionsMap.get(rowIndex).indexOf(value);
}
}

Or you could do something like creating a custom cell, which has methods you can call in the getValue of that particular column
say
final DynamicSelectionCell selection = new DynamicSelectionCell("...");
Column<GraphFilterCondition, String> operandColumn=new Column<GraphFilterCondition, String>(selection) {
#Override
public String getValue(FilterCondition object) {
if(object.getWhereCol()!=null){
((DynamicSelectionCell)this.getCell()).addOptions(new String[]{">","<",">="});
}
if(object.getWhereCondition()!=null){
return object.getWhereCondition().getGuiName();
}
return "";
}
};
This should work I guess.
Also check this other question