Question

I am developing an application which requires me to create a progress bar moving from right to left.

I tried using GaugeField by filling startVal as 100 and then on decrementing it but I couldn’t achieve it.

Is there any way in BlackBerry say paint() method or drawRect() using timer where we can fill it from right to left?

Answer 1

Check following code for an implementation of Custom GaugeField.

Output

Implementation of CustomGaugeField

class CustomGaugeField extends GaugeField {
    // Default constructor, need improvement
    public CustomGaugeField() {
        super("", 0, 100, 0, GaugeField.PERCENT);
    }

    // Colors
    private static final int BG_COLOR = 0xd6d7d6;
    private static final int BAR_COLOR = 0x63cb52;
    private static final int FONT_COLOR = 0x5a55c6;

    protected void paint(Graphics graphics) {
        int xProgress = (int) ((getWidth() / 100.0) * getValue());
        int xProgressInv = getWidth() - xProgress;

        // draw background
        graphics.setBackgroundColor(BG_COLOR);
        graphics.clear();

        // draw progress bar
        graphics.setColor(BAR_COLOR);
        graphics.fillRect(xProgressInv, 0, xProgress, getHeight());

        // draw progress indicator text
        String text = getValue() + "%";
        Font font = graphics.getFont();
        int xText = (getWidth() - font.getAdvance(text)) / 2;
        int yText = (getHeight() - font.getHeight()) / 2;
        graphics.setColor(FONT_COLOR);
        graphics.drawText(text, xText, yText);
    }
}

How to use

class MyScreen extends MainScreen {

    public MyScreen() {
        setTitle("Custom GaugeField Demo");
        GaugeField gField;
        for (int i = 0; i < 6; i++) {
            gField = new CustomGaugeField();
            gField.setMargin(10, 10, 10, 10);
            add(gField);
        }
        startProgressTimer();
    }

    private void startProgressTimer() {
        TimerTask ttask = new TimerTask() {
            public void run() {
                Field f;
                for (int i = 0; i < getFieldCount(); i++) {
                    f = getField(i);
                    if (f instanceof CustomGaugeField) {
                        final CustomGaugeField gField = (CustomGaugeField) f;
                        final int increment = (i + 1) * 2;
                        UiApplication.getUiApplication().invokeLater(
                            new Runnable() {
                                public void run() {
                                    gField.setValue((gField.getValue() + increment) % 101);
                                }
                            }
                        );
                    }
                }

            }
        };

        Timer ttimer = new Timer();
        ttimer.schedule(ttask, 1000, 300);
    }
}