Java Development

[frandelbetis]

Hello,

I´m using TableLayoutManager in my project. This is an example of my problem:

I have this code:

public MyScreen() {
		setTitle("TableLayoutManager_Example");

		VerticalFieldManager vfm0 = new VerticalFieldManager();
		vfm0.setBorder(BorderFactory.createSimpleBorder(new XYEdges(10, 10, 10, 10), Border.STYLE_TRANSPARENT));
		VerticalFieldManager vfm = new VerticalFieldManager();
		vfm.setBorder(BorderFactory.createRoundedBorder(new XYEdges(5, 5, 5, 5)));




		TableLayoutManager table = new TableLayoutManager(new int[] { TableLayoutManager.USE_PREFERRED_SIZE,
				TableLayoutManager.SPLIT_REMAINING_WIDTH, }, null, 0, Manager.NO_HORIZONTAL_SCROLL
				| Manager.NO_VERTICAL_SCROLL);


		LabelField lb=new LabelField("Label1    ");
		HorizontalFieldManager hfm=new HorizontalFieldManager();
		TextField tf=new TextField();
		LabelField lb2=new LabelField("Label2",Field.FOCUSABLE);
		tf.setText("Text");
		tf.setMaxSize(5);

		hfm.add(lb2);
		hfm.add(tf);



		LabelField lb3=new LabelField("Label3");
		LabelField lb4=new LabelField("Label4",Field.FOCUSABLE);

		table.add(lb);
		table.add(hfm);
		table.add(new SeparatorField());
		table.add(new SeparatorField());
		table.add(lb3);
		table.add(lb4);

		vfm.add(table);
		vfm0.add(vfm);
		add(vfm0);
}

The problem is that I can´t put the focus in the TextField. If I just add to table the components lb and hfm  it works, but If I add others focusable components (like example) I can´t put the focus in the TextField, the focus set in Label4:

What can I do?

Thank you.

[peter_strange]

TableLayoutManager was written to handle one focusable element per 'cell' and as a result, will move focus to the next cell on focus movement events.  Have a good look at the navigationMovement() method to get an idea of the assumptions and the impact that this has. 

I don't think there is no easy way around this other than re-writing the focus movement methods in TableLayoutManager to detect that the cell has multiple possibilities and pass control to it for these events.  This would be doable, and if I was better and these things I might think it would be easy, but this is not something I am very good at.  Perhaps some other forum contributor might help if you decide that is what you want to do. 

[frandelbetis]

Finally, I´ve replaced the TableLayoutManager for GridFieldManager. However, I´m going to continue investigating about focus movement methods, like you´ve said me.

If I discover something, I will post it.

[frandelbetis · Accepted solution]

I´ve found a good solution. I´ve overwritten the navigationMovement method of TableLayoutManager. This is the code:

/**
	 * Navigation movement to allow for both cell to cell within a columns and row movement
	 */
	protected boolean navigationMovement(int dx, int dy, int status, int time) {
		int focusIndex = getFieldWithFocusIndex();
		int dirY = (dy > 0) ? 1 : -1;
		int absY = Math.abs(dy);

		for (int y = 0; y < absY; y++) {
			focusIndex += _columns * dirY;
			if (focusIndex < 0 || focusIndex >= getFieldCount()) {
				//#ifdef BlackBerrySDK4.5.0
				this.invalidate(); //ref #217
				//#endif
				return false;
			} else {
				Field f = getField(focusIndex);
				if (f.isFocusable()) {
					f.setFocus();
				} else
					y--; // do it over again
			}
		}

		int dirX = (dx > 0) ? 1 : -1;
		int absX = Math.abs(dx);
		for (int x = 0; x < absX; x++) {
			focusIndex += dirX;
			if (focusIndex < 0 || focusIndex >= getFieldCount()) {
				//#ifdef BlackBerrySDK4.5.0
				this.invalidate(); //Ref #217
				//#endif
				return false;
			} else {
				Field f = getField(focusIndex);
				if (f.isFocusable()) {

////////////////////////NEW CODE /////////////////////////////////////

					if(f instanceof Manager){
						int fieldsInManager=((Manager)f).getFieldCount();
						if(fieldsInManager>0){
							for(int i=0;i<fieldsInManager;i++){
								Field field=((Manager)f).getField(i);
								if(field.isFocusable()){
									field.setFocus();
								}
							}
						}
					}
//////////////////////////////////////////////////////////////////////
				} else
					x--; // do it over again
			}
			focusIndex += dirX;
		}

		//#ifdef BlackBerrySDK4.5.0
		this.invalidate(); //ref #217
		//#endif

		return true;
	}

 I look for a manager inside the cell. If I found it, I set the focus in its elements. This works with a manager with one or more focusable elements. 

If you see it right, you could add this code to your original code 

Thank you.

[peter_strange]

Not sure your code copes with both left and right trackpad movements properly.  That said, it is along the lines I was thinking when I posted previously.  I think there are Manager focus methods, like nextFocus that might make it easier to figure out.  Your approach is a little 'bruteforce', I suspect there are better ways. 

Anyway, if it is working well enough for you, great.  I think your code would be a good start for the next person who has this problem.