Question

I’m trying to make an embedded web page on my blackberry app, and I’m having trouble setting the starting URL.

I can only set the URL when I do it from a callback from a TextField. When I try to do it after I push the new screen on, the app no longer works (it does nothing when you try to run it.

The code that works is the following:

protected boolean keyChar(char key, int status, int time) 
{
    if ( key == Characters.ENTER ) 
    {
        Application.getApplication().invokeLater( new Runnable() 
            {
                public void run() {                     
                    //progressBar.reset("", 0, 100, 0);
                    browserField.requestContent(locationBar.getText().trim());
                } 
            });
        return true;
    } 
    return super.keyChar(key, status, time);
}

When I try to set it automatically after everything is created, nothing happens when I run the app.

Code snippet

public MyApp() 
{
    pushScreen(new BrowserFieldScreen());

    // if I have this here, the app will not open
    Application.getApplication().invokeLater( new Runnable() 
        {
            public void run() {                     
                gBrowserField.requestContent("http://google.com");
            } 
    });
}

The complete program:

package mypackage;

import java.util.Enumeration;
import java.util.Hashtable;

import net.rim.device.api.browser.field.ContentReadEvent;
import net.rim.device.api.browser.field2.BrowserField;
import net.rim.device.api.browser.field2.BrowserFieldListener;
import net.rim.device.api.system.Application;
import net.rim.device.api.system.Characters;
import net.rim.device.api.ui.Color;
import net.rim.device.api.ui.Field;
import net.rim.device.api.ui.Manager;
import net.rim.device.api.ui.UiApplication;
import net.rim.device.api.ui.component.GaugeField;
import net.rim.device.api.ui.component.TextField;
import net.rim.device.api.ui.container.MainScreen;
import net.rim.device.api.ui.container.VerticalFieldManager;
import net.rim.device.api.ui.decor.BackgroundFactory;

import org.w3c.dom.Document;  

/**
 * BrowserField2ProgressTracker
 * - A BrowserField2 Mini-browser application that keeps track of page-loading progress
 *   and displays progress information to the user.
 */

public class MyApp extends UiApplication {


    static BrowserField gBrowserField;
    public static void main(String[] args){
        MyApp theApp = new MyApp();
        theApp.enterEventDispatcher();
    } 

    public MyApp() {
        pushScreen(new BrowserFieldScreen());
    /*  
        if I have this hear, the ap will not open
        Application.getApplication().invokeLater( new Runnable() {
            public void run() {                     
                gBrowserField.requestContent("http://google.com");
            } 
        });
    }
    */
}

/**
 * BrowserFieldScreen
 * - A screen that contains a location bar, a progress bar, and a browser field
 */
class BrowserFieldScreen extends MainScreen {

    // The location bar where URL will be typed in
    private TextField locationBar;  


    // The BrowserField 
    private BrowserField browserField;


    public BrowserFieldScreen() {
//      progressTracker = new BrowserFieldLoadProgressTracker(10f);
        createGUI();


    }

    private void createGUI() {

        VerticalFieldManager mainManager = new VerticalFieldManager(Field.USE_ALL_WIDTH | Field.USE_ALL_HEIGHT | Manager.VERTICAL_SCROLLBAR | Manager.HORIZONTAL_SCROLLBAR );

        locationBar = new TextField() {

            protected boolean keyChar(char key, int status, int time) {
                if ( key == Characters.ENTER ) {
                    Application.getApplication().invokeLater( new Runnable() {
                        public void run() {                     
                            //progressBar.reset("", 0, 100, 0);
                            browserField.requestContent(locationBar.getText().trim());
                        } 
                    });
                    return true;
                } 
                return super.keyChar(key, status, time);
            } 
        };

        locationBar.setBackground(BackgroundFactory.createSolidBackground(Color.BEIGE));
        locationBar.setText("http://google.com");
        browserField = new BrowserField();

        MyApp.gBrowserField=browserField;
        mainManager.add(locationBar);
        mainManager.add(browserField);
        add(mainManager);   
    } 
}

Answer 1

I don’t think you can call invokeLater() until your app, theApp has enter the main event thread. Which is done by calling theApp.enterEventDispatcher()

instead try changing your BrowserFieldScreen constructor to:

public BrowserFieldScreen() {
    //      progressTracker = new BrowserFieldLoadProgressTracker(10f);
    createGUI();
    browserField.requestContent("http://google.com");
}