Java Development

[amardeepjaiman]

hi,

How to draw any image in background of MainScreen ? the solutions mentioned in other threads of forum, is not working .

The solution mentioned using Background Class works but that API is provided only in 4.7.

For other JDK problem still remains.

[simon_hain]

use a verticalfieldmanager with USE_ALL_HEIGHT and overwrite its paintBackground method.

[BBDeveloper]

package com.samples.backgroundImage;

import net.rim.device.api.ui.*;
import net.rim.device.api.ui.component.*;
import net.rim.device.api.ui.container.*;
import net.rim.device.api.system.*;

public class BackgroundImage extends UiApplication
{
    private Bitmap backgroundBitmap;
    private Bitmap fieldBitmap;
    
    public static void main(String[] args)
    {
            BackgroundImage theApp = new BackgroundImage();
            theApp.enterEventDispatcher();
    }
    
    public BackgroundImage()
    {
        //The background image.
        backgroundBitmap = Bitmap.getBitmapResource("background.png");
        
        MainScreen mainScreen = new MainScreen();
        
        HorizontalFieldManager horizontalFieldManager = new HorizontalFieldManager(HorizontalFieldManager.USE_ALL_WIDTH | HorizontalFieldManager.USE_ALL_HEIGHT){
            
            //Override the paint method to draw the background image.
            public void paint(Graphics graphics)
            {
                //Draw the background image and then call paint.
                graphics.drawBitmap(0, 0, 240, 240, backgroundBitmap, 0, 0);
                super.paint(graphics);
            }            
            
        };
        
        //The LabelField will show up through the transparent image.
        LabelField labelField = new LabelField("This is a label");
        
        //A bitmap field with a transparent image.
        //The background image will show up through the transparent BitMapField image.
        BitmapField bitmapField = new BitmapField(Bitmap.getBitmapResource("field.png"));

        //Add the manager to the screen.
        mainScreen.add(horizontalFieldManager);
        BasicEditField bef = new BasicEditField("To: ","",50,BasicEditField.FILTER_EMAIL);
        horizontalFieldManager.add(bef);
        //Add the fields to the manager.
        horizontalFieldManager.add(labelField);
        horizontalFieldManager.add(bitmapField);
        
        //Push the screen.
        pushScreen(mainScreen);
    }
}

[amardeepjaiman]

If i put listfield in a verticalFeildmanager, and put this manage into given horizontalfield manager, then this code doesnt work, and background image scrolls within list scroll. and some repainting occurs.

Message Edited by amardeepjaiman on 04-14-2009 07:33 PM

[pwerry]

Try this:

class MSBMainScreen extends MainScreen
{
    private VerticalFieldManager _container;
    private Bitmap               _BG;
    
    public MSBMainScreen() 
    {    
        super();
        
        setTitle( "Main Screen Background Hack" );
        
        _BG = Bitmap.getBitmapResource( "background.png" );
        
        _container = new VerticalFieldManager( Manager.VERTICAL_SCROLL | Manager.VERTICAL_SCROLLBAR ) {
            protected void paint( Graphics g )
            {
                // Instead of these next two lines, draw your bitmap
                int y = MSBMainScreen.this.getMainManager().getVerticalScroll();
                
                g.drawBitmap( 0, y, _BG.getWidth(), _BG.getHeight(), _BG, 0, 0 );
                
                super.paint( g );
            }
            
            // The keydown and navigation overrides are a workaround
            // for an optimization hack RIM performed, perhaps assuming that
            // Managers would not try to take control of painting on
            // a MainScreen.
            protected boolean keyDown( int keycode, int status )
            {
                invalidate();
                
                return super.keyDown( keycode, status );
            }
            
            protected boolean navigationMovement( int dx, int dy, int status, int time )
            {
                invalidate();
                
                return super.navigationMovement( dx, dy, status, time );
            }
        };
        
        super.add( _container );
    }
    
    
    public void add( Field field )
    {
        _container.add( field );
    }
    
    public void delete( Field field )
    {
        _container.delete( field );
    }
    
    // Implement the rest of the field manipulation functions to redirect ro the new container
    
} 

Cheers

*edit* This seems like a lot of hacking just to draw an image in the BG. Is there any specific piece of functionality you need from a MainScreen that you can't get from a FullScreen?

Message Edited by pwerry on 04-15-2009 03:07 AM

[Rajat_10Sep]

Hi,

Thanks a lot your solution it really works.

One more thing we have to also overide moveFocus() of Manager so that in case of trackball move , image get painted properly.

here is the code for that

protected int moveFocus(int amount, int status, int time){
              invalidate();
               return super.moveFocus(amount, status, time);
            } 

The reason behind using mainscreen might be to avoid implementation on touch events.

[pwerry]

Hi Rajat,

Overriding navigationMovement() should be enough. Are you observing something different? 

[Rajat_10Sep]

Hi,

Yes actually I am also adding listField in this manager, so when i scroll with in listfield the image in manager do not paint itself properly so i added that piece of code and it worked fined

[pwerry]

That's very odd because that's exactly how I tested this one. 

Check this out and let me know if there's something you do differently:

class MSBMain extends UiApplication
{
    public static void main( String[] args )
    {
        new MSBMain().enterEventDispatcher();
    }
    
    MSBMain() 
    {
        // The following is really lazy code. Do not do this in
        // a consumer grade app :)
        
        String[] objects = new String[20];
        
        for ( int i = 0; i < 20; i++ )
        {
            objects[i] = "Line: " + (i + 1);
        }
        
        ObjectListField olf = new ObjectListField();
        olf.set( objects );
        
        MSBMainScreen msbms = new MSBMainScreen();
        
        msbms.add( olf );
            
        pushScreen( msbms );
    }
} 

[Rajat_10Sep]

Hi,

Sorry for replying late

below is the code which i am using

import net.rim.device.api.ui.container.MainScreen;
import net.rim.device.api.ui.container.VerticalFieldManager;
import net.rim.device.api.ui.component.BitmapField;
import net.rim.device.api.ui.Graphics;
import net.rim.device.api.ui.Field;
import net.rim.device.api.ui.component.ListField;
import net.rim.device.api.ui.component.ListFieldCallback;
import net.rim.device.api.system.Bitmap;
import net.rim.device.api.ui.Manager;

class MSBMainScreen extends MainScreen
                    implements ListFieldCallback {
    
    String Data[] = {"Task ID","Priority","Task Name","Location","Task Type","State","AAA","BBB","CCCC","DDD","EEE","FFFF","GGGG","HHHH","IIII"};    
    
    private VerticalFieldManager objManager;
    private Bitmap               objBitmap;
    
  ListField objList = null;
    
    public MSBMainScreen(){    
        super();
        drawComponent();
        setTitle( "Inbox Screen" );
        
        objBitmap = Bitmap.getBitmapResource( "watermark.png");
        
        objManager = new VerticalFieldManager( Manager.VERTICAL_SCROLL | Manager.VERTICAL_SCROLLBAR ) {
            protected void paint( Graphics g ){
                int y = MSBMainScreen.this.getMainManager().getVerticalScroll();
                
                g.drawBitmap( 0, y, objBitmap.getWidth(), objBitmap.getHeight(), objBitmap, 0, 0 );
                super.paint( g );
            }
            
            
                       
            protected boolean keyDown( int keycode, int status ){
                invalidate();
                return super.keyDown( keycode, status );
            }
            
            protected boolean navigationMovement( int dx, int dy, int status, int time ){
                invalidate();
                return super.navigationMovement( dx, dy, status, time );
            }
            
            protected int moveFocus(int amount, int status, int time){
               invalidate();
               return super.moveFocus(amount, status, time);
            }
            
        };
        
        add(objList);
        
        super.add( objManager );
    }
    
    
    public void add( Field field ){
        objManager.add( field );
    }
    
    public void delete( Field field ){
        objManager.delete( field );
    }
    
    public void drawListRow(ListField listField, Graphics g, int index, int y, int width){
       g.drawText(Data[index], /*10*/10, /*CTIAMain.ROW_HEIGHT*index*/y );  
    }
    
    public int indexOfList(ListField listField, String prefix, int start){
       
            return 0;
    }
    
    public Object get(ListField listField, int index){
           return Data[index];
    } 
    
    public int getPreferredWidth(ListField listField){
        return 0;
    }
    
    private void drawComponent(){
                 
        objList = new ListField(Data.length);
        objList.setCallback(this);
        
    }
    
} 

If i comment moveFocu() then , when i press trackball the image below list does not paint itself properly, but if i uncomment moveFocu() it works fine.