Rokuon.java :  » UnTagged » kyoto-gtug » rokuon » client » Android Open Source

package rokuon.client;

import rokuon.shared.FieldVerifier;
import com.google.gwt.core.client.EntryPoint;
import com.google.gwt.core.client.GWT;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.event.dom.client.KeyCodes;
import com.google.gwt.event.dom.client.KeyUpEvent;
import com.google.gwt.event.dom.client.KeyUpHandler;
import com.google.gwt.user.client.rpc.AsyncCallback;
import com.google.gwt.user.client.ui.Button;
import com.google.gwt.user.client.ui.DialogBox;
import com.google.gwt.user.client.ui.HTML;
import com.google.gwt.user.client.ui.Label;
import com.google.gwt.user.client.ui.RootPanel;
import com.google.gwt.user.client.ui.TextBox;
import com.google.gwt.user.client.ui.VerticalPanel;

/**
 * Entry point classes define <code>onModuleLoad()</code>.
 */
public class Rokuon implements EntryPoint {
  /**
   * The message displayed to the user when the server cannot be reached or
   * returns an error.
   */
  private static final String SERVER_ERROR = "An error occurred while " + "attempting to contact the server. Please check your network " + "connection and try again.";

  /**
   * Create a remote service proxy to talk to the server-side Greeting service.
   */
  private final GreetingServiceAsync greetingService = GWT.create( GreetingService.class );

  /**
   * This is the entry point method.
   */
  public void onModuleLoad() {
    final Button sendButton = new Button( "Send" );
    final TextBox nameField = new TextBox();
    nameField.setText( "GWT User" );
    final Label errorLabel = new Label();

    // We can add style names to widgets
    sendButton.addStyleName( "sendButton" );

    // Add the nameField and sendButton to the RootPanel
    // Use RootPanel.get() to get the entire body element
    RootPanel.get( "nameFieldContainer" ).add( nameField );
    RootPanel.get( "sendButtonContainer" ).add( sendButton );
    RootPanel.get( "errorLabelContainer" ).add( errorLabel );

    // Focus the cursor on the name field when the app loads
    nameField.setFocus( true );
    nameField.selectAll();

    // Create the popup dialog box
    final DialogBox dialogBox = new DialogBox();
    dialogBox.setText( "Remote Procedure Call" );
    dialogBox.setAnimationEnabled( true );
    final Button closeButton = new Button( "Close" );
    // We can set the id of a widget by accessing its Element
    closeButton.getElement().setId( "closeButton" );
    final Label textToServerLabel = new Label();
    final HTML serverResponseLabel = new HTML();
    VerticalPanel dialogVPanel = new VerticalPanel();
    dialogVPanel.addStyleName( "dialogVPanel" );
    dialogVPanel.add( new HTML( "<b>Sending name to the server:</b>" ) );
    dialogVPanel.add( textToServerLabel );
    dialogVPanel.add( new HTML( "<br><b>Server replies:</b>" ) );
    dialogVPanel.add( serverResponseLabel );
    dialogVPanel.setHorizontalAlignment( VerticalPanel.ALIGN_RIGHT );
    dialogVPanel.add( closeButton );
    dialogBox.setWidget( dialogVPanel );

    // Add a handler to close the DialogBox
    closeButton.addClickHandler( new ClickHandler() {
      public void onClick( ClickEvent event ) {
        dialogBox.hide();
        sendButton.setEnabled( true );
        sendButton.setFocus( true );
      }
    } );

    // Create a handler for the sendButton and nameField
    class MyHandler implements ClickHandler, KeyUpHandler {
      /**
       * Fired when the user clicks on the sendButton.
       */
      public void onClick( ClickEvent event ) {
        sendNameToServer();
      }

      /**
       * Fired when the user types in the nameField.
       */
      public void onKeyUp( KeyUpEvent event ) {
        if ( event.getNativeKeyCode() == KeyCodes.KEY_ENTER ) {
          sendNameToServer();
        }
      }

      /**
       * Send the name from the nameField to the server and wait for a response.
       */
      private void sendNameToServer() {
        // First, we validate the input.
        errorLabel.setText( "" );
        String textToServer = nameField.getText();
        if ( !FieldVerifier.isValidName( textToServer ) ) {
          errorLabel.setText( "Please enter at least four characters" );
          return;
        }

        // Then, we send the input to the server.
        sendButton.setEnabled( false );
        textToServerLabel.setText( textToServer );
        serverResponseLabel.setText( "" );
        greetingService.greetServer( textToServer, new AsyncCallback<String>() {
          public void onFailure( Throwable caught ) {
            // Show the RPC error message to the user
            dialogBox.setText( "Remote Procedure Call - Failure" );
            serverResponseLabel.addStyleName( "serverResponseLabelError" );
            serverResponseLabel.setHTML( SERVER_ERROR );
            dialogBox.center();
            closeButton.setFocus( true );
          }

          public void onSuccess( String result ) {
            dialogBox.setText( "Remote Procedure Call" );
            serverResponseLabel.removeStyleName( "serverResponseLabelError" );
            serverResponseLabel.setHTML( result );
            dialogBox.center();
            closeButton.setFocus( true );
          }
        } );
      }
    }

    // Add a handler to send the name to the server
    MyHandler handler = new MyHandler();
    sendButton.addClickHandler( handler );
    nameField.addKeyUpHandler( handler );
  }
}