Troubleshooting guide

ManualsBrandsBlackberry ManualsOtherJAVA DEVELOPMENT ENVIRONMENT - - CRYPTOGRAPHIC SMART CARD DRIVER - DEVELOPMENT GUIDE

1: Creating UIs

Define the appearance

of the custom field.

1. Perform complex calculations in layout()instead of in paint().

2. Implement paint().

protected void paint(Graphics graphics) {

int textX, textY, textWidth;

int w = getWidth();

switch(_shape) {

case TRIANGLE:

int h = (w>>1);

int m = (w>>1)-1;

graphics.drawLine(0, h-1, m, 0);

graphics.drawLine(m, 0, w-1, h-1);

graphics.drawLine(0, h-1, w-1, h-1);

textWidth = Math.min(_labelWidth,h);

textX = (w - textWidth) >> 1;

textY = h >> 1;

break;

case OCTAGON:

int x = 5*w/17;

int x2 = w-x-1;

int x3 = w-1;

graphics.drawLine(0, x, 0, x2);

graphics.drawLine(x3, x, x3, x2);

graphics.drawLine(x, 0, x2, 0);

graphics.drawLine(x, x3, x2, x3);

graphics.drawLine(0, x, x, 0);

graphics.drawLine(0, x2, x, x3);

graphics.drawLine(x2, 0, x3, x);

graphics.drawLine(x2, x3, x3, x2);

textWidth = Math.min(_labelWidth, w - 6);

textX = (w-textWidth) >> 1;

textY = (w-_labelHeight) >> 1;

break;

case RECTANGLE: default:

graphics.drawRect(0, 0, w, getHeight());

textX = 4;

textY = 2;

textWidth = w - 6;

break;

}

graphics.drawText(_label, textX, textY, (int)( getStyle() & DrawStyle.ELLIPSIS |

DrawStyle.HALIGN_MASK ), textWidth );

}

The fields manager invokes paint() to redraw the field whenever an area of the field is marked as invalid.

Paint a field only within

the visible region.

>Invoke Graphics.getClippingRect().

Manage focus events. >Use the Field.FOCUSABLE style and implement Field.moveFocus().

Change the appearance

of the default focus

indicator.

> Override drawFocus().

Task Steps