Keyword Search for ListField in Blackberry - blackberry-jde

Question

I am creating a ListField. in each row of I am adding a image and 3 labelfield.
Can any one tell me how to create a keywordfilterField for this...
Thanks in advance
I am new to blackberry.
Little code will help me alot
This is my code for creating a custom list
class CustomListField extends ListField implements ListFieldCallback
{
String type;
int DISPLAY_WIDTH = Display.getWidth();
int DISPLAY_HEIGHT = Display.getHeight();
Vector mItems = new Vector();
Vector mine = new Vector();
Vector three= new Vector();
// SizedVFM mListManager = new SizedVFM(DISPLAY_WIDTH, DISPLAY_HEIGHT - 40);
Bitmap searchresult = Bitmap.getBitmapResource("res/searchresult.png");
HorizontalFieldManager hfManager;
Bitmap image ,image1;
int z = this.getRowHeight();
CustomListField(String text1,String text2,String type)
{
for (int i = 1; i < 31; i++)
{
mItems.addElement(text1 +String.valueOf(i));
mine.addElement(" "+text2);
three.addElement("31");
}
this.type=type;
this.setRowHeight((2*z));
this.setCallback(this);
this.setSize(20);
//mListManager.add(mListField);
//add(mListManager);
}
public void drawListRow(ListField field, Graphics g, int i, int y, int w)
{
// Draw the text.
image = Bitmap.getBitmapResource("res/searchresult.png");
String text = (String) get(field, i);
String mytext = (String)mine.elementAt(i);
String urtext=(String)three.elementAt(i);
g.drawBitmap(0, y, image.getWidth(),image.getHeight(), image, 0, 0);
g.drawText(text, image.getWidth(), y, 0, w);
g.setColor(Color.GRAY);
g.drawText(mytext, image.getWidth(), y+getFont().getHeight(), 0, w);
g.drawText(urtext,Graphics.getScreenWidth()*7/8,y,0,w);
if (i != 0)
{
g.drawLine(0, y, w, y);
}
}
public Object get(ListField listField, int index)
{
return mItems.elementAt(index);
}
public int getPreferredWidth(ListField listField)
{
return DISPLAY_WIDTH;
}
public int indexOfList(ListField listField, String prefix, int start)
{
return 0;
}
protected boolean touchEvent(TouchEvent message)
{
// If click, process Field changed
if ( message.getEvent() == TouchEvent.CLICK )
{
if(type.equals("Stops"))
UiApplication.getUiApplication().pushScreen(new SearchScreen("Services"));
else if(type.equals("Services"))
UiApplication.getUiApplication().pushScreen(new SearchScreen("Stops"));
return true;
}
return super.touchEvent(message);
}
}

Answer 1

The problem with KeywordFilterField is that it uses internally its own ListField, so I think it is going to be difficult to customize. If you wanted to use it as it is provided, you'll have to use it as follows:
//KeywordFilterField contains a ListField to display and a search edit field to type in the words
KeywordFilterField keywordFilterField = new KeywordFilterField();
//Instantiate the sorted collection:
CustomList cl = new CustomList(mItems);
//Pass the custom collection
keywordFilterField.setSourceList(cl, cl);
//Now you have to add two fields: first the list itself
myManager.add(keywordFilterField);
//And the search field, probably you'd want it at top:
myScreen.setTitle(keywordFilterField.getKeywordField());
You'll have to implement a custom sortable collection to hold the items you wan't to display:
class CustomList extends SortedReadableList implements KeywordProvider {
//In constructor, call super constructor with a comparator of <yourClass>
public CustomList(Vector elements)
{
super(new <yourClass>Comparator()); //pass comparator to sort
loadFrom(elements.elements());
}
//Interface implementation
public String[] getKeywords( Object element )
{
if(element instanceof <yourClass> )
{
return StringUtilities.stringToWords(element.toString());
}
return null;
}
void addElement(Object element)
{
doAdd(element);
}
//...
}
You have a full demo available inside the JDE samples folder. It is called keywordfilterdemo.
To use a custom list like the one you posted, you'll probably have to code a lot of stuff, like a custom EditField to type in the keywords receiving events on every typed character, linked to a search on a sortered collection (maybe you could use a SortedReadableList for this) which will select in your ListField the first search result returned by this collection.