How to setBackground of Field in Blackberry 4.5? - blackberry

Question

I have defined a BitmapButtonField in Blackberry. But the default grey color background does not go. And the Bluish onFocus border?
How to change them in BB 4.5

Answer 1

Hi this is bitmap button and background color Red
manager=new Field(Field.FOCUSABLE){
protected void onFocus(int direction) {
super.onFocus(direction);
flag1=true;
invalidate();
}
protected void onUnfocus() {
flag1=false;
invalidate();
}
protected void layout(int width, int height) {
setExtent(image.getWidth(),image.getHeight());
}
protected void paint(Graphics graphics) {
if(flag1){
graphics.setBackgroundColor(Color.RED);
graphics.clear();
graphics.drawBitmap(0, 0, image.getWidth(),image.getHeight(), image_hover,0,0);
}else{
graphics.drawBitmap(0, 0, image.getWidth(),image.getHeight(), image,0,0);
}
}
protected boolean navigationClick(int status, int time) {
fieldChangeNotify(1);
return true;
}
};
manager.setChangeListener(this);
add(manager);
output as following image
This is background image and with default background color
manager1=new Field(Field.FOCUSABLE){
protected void onFocus(int direction) {
super.onFocus(direction);
flag2=true;
invalidate();
}
protected void onUnfocus() {
button=image;
flag2=false;
invalidate();
}
protected void layout(int width, int height) {
setExtent(image.getWidth(),image.getHeight());
}
protected void paint(Graphics graphics) {
if(flag2)
graphics.drawBitmap(0, 0, image.getWidth(),image.getHeight(), image_hover,0,0);
else
graphics.drawBitmap(0, 0, image.getWidth(),image.getHeight(), image,0,0);
}
protected boolean navigationClick(int status, int time) {
fieldChangeNotify(1);
return true;
}
};
manager1.setChangeListener(this);
add(manager1);
out put as following
Fully functional class is following for better understanding
import net.rim.device.api.system.Bitmap;
import net.rim.device.api.ui.Color;
import net.rim.device.api.ui.Field;
import net.rim.device.api.ui.FieldChangeListener;
import net.rim.device.api.ui.Graphics;
import net.rim.device.api.ui.UiApplication;
import net.rim.device.api.ui.component.Dialog;
import net.rim.device.api.ui.container.MainScreen;
public class StartUp extends UiApplication{
public static void main(String[] args) {
StartUp up=new StartUp();
up.enterEventDispatcher();
}
public StartUp()
{
pushScreen(new Demoscreen());
}
class Demoscreen extends MainScreen implements FieldChangeListener
{
Bitmap image,image_hover;
boolean flag1,flag2;
Field manager=null,manager1=null;
public Demoscreen() {
image=Bitmap.getBitmapResource("Download_48x48.png");
image_hover=Bitmap.getBitmapResource("Download_48x48.png");
manager=new Field(Field.FOCUSABLE){
protected void onFocus(int direction) {
super.onFocus(direction);
flag1=true;
invalidate();
}
protected void onUnfocus() {
flag1=false;
invalidate();
}
protected void layout(int width, int height) {
setExtent(image.getWidth(),image.getHeight());
}
protected void paint(Graphics graphics) {
if(flag1){
graphics.setBackgroundColor(Color.RED);
graphics.clear();
graphics.drawBitmap(0, 0, image.getWidth(),image.getHeight(), image_hover,0,0);
}else{
graphics.drawBitmap(0, 0, image.getWidth(),image.getHeight(), image,0,0);
}
}
protected boolean navigationClick(int status, int time) {
fieldChangeNotify(1);
return true;
}
};
manager.setChangeListener(this);
add(manager);
manager1=new Field(Field.FOCUSABLE){
protected void onFocus(int direction) {
super.onFocus(direction);
flag2=true;
invalidate();
}
protected void onUnfocus() {
flag2=false;
invalidate();
}
protected void layout(int width, int height) {
setExtent(image.getWidth(),image.getHeight());
}
protected void paint(Graphics graphics) {
if(flag2)
graphics.drawBitmap(0, 0, image.getWidth(),image.getHeight(), image_hover,0,0);
else
graphics.drawBitmap(0, 0, image.getWidth(),image.getHeight(), image,0,0);
}
protected boolean navigationClick(int status, int time) {
fieldChangeNotify(1);
return true;
}
};
manager1.setChangeListener(this);
add(manager1);
}
public void fieldChanged(Field field, int context) {
if(field==manager)
{
displayDialog("I am first field");
}else if(field==manager1)
{
displayDialog("I am second field");
}
}
public void displayDialog(final String message)
{
UiApplication.getUiApplication().invokeLater(new Runnable() {
public void run() {
Dialog.inform(message);
}
});
}
}
}
For more details please visit following link for BackgroundsBackground logic for 4.5 OS

Answer 2

Check following links for customized Button Field:
Implement advanced buttons, fields, and managers.
User Defined Buttons - Create a Custom Button From an Image
Blackberry Custom Button Field
How to create a Custom Button Field in Blackberry
Normally overriding applyTheme(..) (an empty implementation) removes default styling of a field. Also we need to override paint(..), paintBackground(..), drawFocus(..) and change their implementation according to current focus status of the field. Below is a code snippet for the case when I extend a Field for making Custom Button Field.
private final Bitmap focusedBitMap = Bitmap.getBitmapResource("focused.png");
private final Bitmap unfocusedBitmap = Bitmap.getBitmapResource("unfocused.png");
protected void paint(Graphics graphics) {
// paint background
graphics.setBackgroundColor(isFocus() ? Color.RED : Color.GREEN);
graphics.clear();
// draw button image
Bitmap myBitmap = isFocus() ? focusedBitMap : unfocusedBitmap;
if (myBitmap != null) {
// image position calculation
int imageX = 0;
int imageY = 0;
graphics.drawBitmap(imageX, imageY,
myBitmap.getWidth(), myBitmap.getHeight(),
myBitmap, 0, 0);
}
}
protected void drawFocus(Graphics graphics, boolean on) {
}
public boolean isFocusable() {
return true;
}