If you want to display a bar graph, then lets try this code sample. This will help you in drawing a bar graph in blackberry.
//BarScreen - MainScreen class ---
import net.rim.device.api.ui.component.NullField;
import net.rim.device.api.ui.container.MainScreen;
import net.rim.device.api.ui.container.VerticalFieldManager;
public class BarScreen extends MainScreen
{
private BarGraphField _bar;
private boolean _barChanged = false;
private MainScreen _barScreen;
public BarScreen(long style)
{
super(style);
_barScreen = this;
//Graph data.
VerticalFieldManager graphLayout = new VerticalFieldManager(VerticalFieldManager.FIELD_VCENTER);
final int[] values = {60,50,40,30,20,10};
final int[] colors = {0x00FF0000,0x007F525D , 0x00E77471, 0x00C8B560, 0x00ADDFFF,0};
_bar = new BarGraphField(values, colors, 100, 5, 30, BarGraphField.PADDING_MEDIUM, BarGraphField.PADDING_HIGH, true);
//Add a focusable NullField for scrolling purposes.
this.add(new NullField(NullField.FOCUSABLE));
_bar.setPadding(20, 0, 0, 20);
graphLayout.add(_bar);
this.add(graphLayout);
this.add(new NullField(NullField.FOCUSABLE));
}
}
// BarGraphField class--------
import net.rim.device.api.ui.Graphics;
import net.rim.device.api.util.Arrays;
import net.rim.device.api.ui.Font;
public class BarGraphField extends GraphField
{
public static final int PADDING_NONE = 0;
public static final int PADDING_LOW = 4;
public static final int PADDING_MEDIUM = 8;
public static final int PADDING_HIGH = 12;
private int _scale, _increment, _barWidth, _barPadding, _scalePadding;
private boolean _showScale;
public BarGraphField(int[] values, int[] colors, int scale, int increment, int barWidth)
{
this(values, colors, scale, increment, barWidth, PADDING_MEDIUM, PADDING_MEDIUM, false);
}
public BarGraphField(int[] values, int[] colors, int scale, int increment, int barWidth, boolean showScale)
{
this(values, colors, scale, increment, barWidth, PADDING_MEDIUM, PADDING_MEDIUM, showScale);
}
public BarGraphField(int[] values, int[] colors, int scale, int increment, int barWidth, int barPadding,
int scalePadding, boolean showScale)
{
//Ensure the scale is greater than 0.
if (scale <= 0)
throw new IllegalArgumentException("Scale must be greater than 0.");
//Ensure the increment is greater than 0.
if (increment <= 0)
throw new IllegalArgumentException("Increment must be greater than 0.");
//Ensure the barWidth is greater than 0.
if (barWidth <= 0)
throw new IllegalArgumentException("Bar width must be greater than 0.");
//Ensure barPadding is a valid value.
switch (barPadding)
{
case PADDING_NONE:
case PADDING_LOW:
case PADDING_MEDIUM:
case PADDING_HIGH:
break;
default:
throw new IllegalArgumentException("Invalid bar padding specified");
}
//Ensure scalePadding is a valid value.
switch (scalePadding)
{
case PADDING_NONE:
case PADDING_LOW:
case PADDING_MEDIUM:
case PADDING_HIGH:
break;
default:
throw new IllegalArgumentException("Invalid scale padding specified");
}
//Ensure the number of bar values match the number of colors.
if (values.length != colors.length)
throw new IllegalArgumentException("Non matching array lengths for values and colors.");
//Ensure not values are greater than the scale value.
for(int count = values.length - 1; count >= 0; --count)
{
if (values[count] > scale)
throw new IllegalArgumentException("Value greater than scale.");
}
_values = values;
_colors = colors;
_scale = scale;
_increment = increment;
_barWidth = barWidth;
_barPadding = barPadding;
_scalePadding = scalePadding;
_showScale = showScale;
_width = calcWidth();
_height = calcHeight();
}
private int calcWidth()
{
int theWidth;
if (_showScale)
theWidth = Font.getDefault().getAdvance(Integer.toString(_scale)) + 8
+ (_values.length * _barWidth) + ((_values.length - 1) * _barPadding);
else
theWidth = 10 + (_values.length * _barWidth) + ((_values.length - 1) * _barPadding);
return theWidth;
}
private int calcHeight()
{
if (_showScale)
return 2 + (Font.getDefault().getHeight() * (_scale / _increment));
else if (_scalePadding == PADDING_NONE)
return 2 + (PADDING_LOW * (_scale / _increment));
else
return 2 + (_scalePadding * (_scale / _increment));
}
protected void paint(Graphics graphics)
{
int count, tempX, tempY, leftOver, graphHeight = 0;
int tickHeight; //The height of the scale ticks.
int tickIndent; //The distance to indent the scale ticks.
if (_showScale)
{
tickHeight = Font.getDefault().getHeight();
//Subtract 4 from the width of the scale (2 pixels for the scale width and 2 pixels for spacing).
tickIndent = Font.getDefault().getAdvance(Integer.toString(_scale)) - 4;
}
else
{
if (_scalePadding == PADDING_NONE)
tickHeight = PADDING_LOW;
else
tickHeight = _scalePadding;
tickIndent = 0;
}
//Wipe out any existing graph image data.
graphics.clear();
graphics.setColor(0);
//In case the increment doesn't divide into the scale evenly.
leftOver = _scale % _increment;
tempY = 0;
//Draw the scale.
for (count = _scale; count > leftOver; count-=_increment)
{
graphics.fillRect(tickIndent, tempY, 6, 2);
if (_showScale)
graphics.drawText(Integer.toString(count), 0, tempY);
tempY += tickHeight;
}
tempX = tickIndent + 6;
//Draw the x axis.
graphics.fillRect(tempX, tempY, _width - tempX, 2);
//Draw the y axis.
graphics.fillRect(tempX, 0, 2, _height);
tempX = _width - _barWidth;
//Draw the bars.
for (count = _values.length - 1; count >= 0; --count)
{
graphics.setColor(_colors[count]);
//Calculate the top bar as a percentage of the available graphing space
//relating to the value. Graphing space is _height - 2 (2 pixel y axis).
tempY = _height - (((_height - 2) * _values[count]) / _scale);
graphHeight = _height - tempY - 2;
graphics.fillRect(tempX, tempY, _barWidth, graphHeight);
//Calculate the next graph starting point.
tempX -= (_barWidth + _barPadding);
}
}
public int getBarPadding()
{
return _barPadding;
}
public int getBarWidth()
{
return _barWidth;
}
public int getIncrement()
{
return _increment;
}
public int getScale()
{
return _scale;
}
public int getScalePadding()
{
return _scalePadding;
}
public boolean isScaleVisible()
{
return _showScale;
}
public void setBarPadding(int barPadding)
{
//Don't do anything unless the bar padding has changed.
if (_barPadding != barPadding)
{
//Ensure barPadding is a valid value.
switch (barPadding)
{
case PADDING_NONE:
case PADDING_LOW:
case PADDING_MEDIUM:
case PADDING_HIGH:
break;
default:
throw new IllegalArgumentException("Invalid bar padding specified");
}
_barPadding = barPadding;
_width = calcWidth();
}
}
public void setBarWidth(int barWidth)
{
//Dont do anything unless the bar width has changed.
if (_barWidth != barWidth)
{
//Ensure the barWidth is greater than 0.
if (barWidth <= 0)
throw new IllegalArgumentException("Bar width must be greater than 0.");
_barWidth = barWidth;
_width = calcWidth();
}
}
public void setGraphData(int[] values, int[] colors)
{
//Don't do anything unless the data has changed.
if (!Arrays.equals(_values, values) || !Arrays.equals(_colors, colors))
{
//Ensure the number of values match the number of colors.
if (values.length != colors.length)
throw new IllegalArgumentException("Non matching array lengths for bars and colors.");
//Ensure not values are greater than the scale value.
for(int count = values.length - 1; count >= 0; --count)
{
if (values[count] > _scale)
throw new IllegalArgumentException("Value greater than scale.");
}
_values = values;
_colors = colors;
_width = calcWidth();
_height = calcHeight();
}
}
public void setIncrement(int increment)
{
//Don't do anything unless the increment has changed.
if (_increment != increment)
{
//Ensure the increment is greater than 0.
if (increment <= 0)
throw new IllegalArgumentException("Increment must be greater than 0.");
//Only the height changes with an increment change.
_increment = increment;
_height = calcHeight();
}
}
public void setScale(int scale)
{
///Don't do anything unless the scale has changed.
if (_scale != scale)
{
//Ensure the scale is greater than 0.
if (scale <= 0)
throw new IllegalArgumentException("Scale must be greater than 0.");
//Ensure no values are greater than the scale value.
for(int count = _values.length - 1; count >= 0; --count)
{
if (_values[count] > scale)
throw new IllegalArgumentException("Value greater than scale.");
}
_scale = scale;
_width = calcWidth();
_height = calcHeight();
}
}
public void setScalePadding(int scalePadding)
{
//Don't do anything unless the scale padding has changed.
if (_scalePadding != scalePadding)
{
//Ensure scalePadding is a valid value.
switch (scalePadding)
{
case PADDING_NONE:
case PADDING_LOW:
case PADDING_MEDIUM:
case PADDING_HIGH:
break;
default:
throw new IllegalArgumentException("Invalid scale padding specified");
}
_scalePadding = scalePadding;
_height = calcHeight();
}
}
public void setScaleVisible(boolean showScale)
{
//Don't do anything unless the flag has changed.
if (_showScale != showScale)
{
_showScale = showScale;
_width = calcWidth();
_height = calcHeight();
}
}
}
//GraphField class ------
import net.rim.device.api.ui.Field;
public abstract class GraphField extends Field
{
protected int[] _values;
protected int[] _colors;
protected int _width;
protected int _height;
GraphField()
{
super();
}
public int getColor(int index)
{
return _colors[index];
}
public int[] getColors()
{
return _colors;
}
public int getValue(int index)
{
return _values[index];
}
public int[] getValues()
{
return _values;
}
public void setGraphData(int[] values, int[] colors)
{
_values = values;
_colors = colors;
}
public int getPreferredHeight()
{
return _height;
}
public int getPreferredWidth()
{
return _width;
}
protected void layout(int width, int height)
{
int w, h;
if (width >= _width)
{
w = _width;
}
else
{
w = width;
}
if (height >= _height)
{
h = _height;
}
else
{
h = height;
}
setExtent(w, h);
}
}
