Troubleshooting guide

25
1: Creating UIs
// Update the cached font in case it has been changed.
_font = getFont();
_labelHeight = _font.getHeight();
_labelWidth = _font.getAdvance(_label);
// Calculate width.
width = Math.min( width, getPreferredWidth() );
// Calculate height.
height = Math.min( height, getPreferredHeight() );
// Set dimensions.
setExtent( width, height );
}
/*
* Redraws this button. The field’s manager invokes this method during the
* repainting process to instruct this field to repaint itself.
*/
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 ),