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Users tend to mistake aligning a view vertically by using android:layout_gravity=”center_vertical”. This holds true in other layouts but does not work under a RelativeLayout.
You will have to use the attribute android:layout_centerVertical=”true“ to make this work.
I had a previous post regarding rotating a JLabel and that involved creating a class that extends the BasicLabelUI class to do the rotation. JButton also has a class of its own called BasicButtonUI that you need to inherit in order to do rotation vertically.
To set the JButton to a certain angle, just set the parameter as either 90 or 270 in the VerticalButtonUI class. Kudos to the developer who created this class (I don’t know who).
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jButton2.setUI(new VerticalButtonUI(90)); |
Here is the code for the VerticalButtonUI class.
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public class VerticalButtonUI extends BasicButtonUI { protected int angle; public VerticalButtonUI(int angle) { super(); this.angle = angle; } @Override public Dimension getPreferredSize(JComponent c) { Dimension dim = super.getPreferredSize(c); return new Dimension( dim.height, dim.width ); } private static Rectangle paintIconR = new Rectangle(); private static Rectangle paintTextR = new Rectangle(); private static Rectangle paintViewR = new Rectangle(); private static Insets paintViewInsets = new Insets(0, 0, 0, 0); @Override public void paint(Graphics g, JComponent c) { JButton button = (JButton)c; String text = button.getText(); Icon icon = (button.isEnabled()) ? button.getIcon() : button.getDisabledIcon(); if ((icon == null) && (text == null)) { return; } FontMetrics fm = g.getFontMetrics(); paintViewInsets = c.getInsets(paintViewInsets); paintViewR.x = paintViewInsets.left; paintViewR.y = paintViewInsets.top; // Use inverted height & width paintViewR.height = c.getWidth() - (paintViewInsets.left + paintViewInsets.right); paintViewR.width = c.getHeight() - (paintViewInsets.top + paintViewInsets.bottom); paintIconR.x = paintIconR.y = paintIconR.width = paintIconR.height = 0; paintTextR.x = paintTextR.y = paintTextR.width = paintTextR.height = 0; Graphics2D g2 = (Graphics2D) g; AffineTransform tr = g2.getTransform(); if (angle == 90) { g2.rotate( Math.PI / 2 ); g2.translate( 0, - c.getWidth() ); paintViewR.x = c.getHeight()/2 - (int)fm.getStringBounds(text, g).getWidth()/2; paintViewR.y = c.getWidth()/2 - (int)fm.getStringBounds(text, g).getHeight()/2; } else if (angle == 270) { g2.rotate( - Math.PI / 2 ); g2.translate( - c.getHeight(), 0 ); paintViewR.x = c.getHeight()/2 - (int)fm.getStringBounds(text, g).getWidth()/2; paintViewR.y = c.getWidth()/2 - (int)fm.getStringBounds(text, g).getHeight()/2; } if (icon != null) { icon.paintIcon(c, g, paintIconR.x, paintIconR.y); } if (text != null) { int textX = paintTextR.x; int textY = paintTextR.y + fm.getAscent(); if (button.isEnabled()) { paintText(g,c,new Rectangle(paintViewR.x,paintViewR.y,textX,textY),text); } else { paintText(g,c,new Rectangle(paintViewR.x,paintViewR.y,textX,textY),text); } } g2.setTransform( tr ); } } |
To rotate a JLabel‘s text vertically, you only need to use this class and pass it as a parameter to the JLabel‘s setUI() method. Kudos to the developer who created this class to make it easy for other developers to plug this class in and create a vertical JLabel in an instant.
To use this class, check the code below:
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JLabel jl = new JLabel("TEST"); jl.setUI(new VerticalLabelUI(true)); |
This is the code for the VerticalLabelUI class.
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public class VerticalLabelUI extends BasicLabelUI { static { labelUI = new VerticalLabelUI(false); } protected boolean clockwise; public VerticalLabelUI(boolean clockwise) { super(); this.clockwise = clockwise; } @Override public Dimension getPreferredSize(JComponent c) { Dimension dim = super.getPreferredSize(c); return new Dimension( dim.height, dim.width ); } private static Rectangle paintIconR = new Rectangle(); private static Rectangle paintTextR = new Rectangle(); private static Rectangle paintViewR = new Rectangle(); private static Insets paintViewInsets = new Insets(0, 0, 0, 0); @Override public void paint(Graphics g, JComponent c) { JLabel label = (JLabel)c; String text = label.getText(); Icon icon = (label.isEnabled()) ? label.getIcon() : label.getDisabledIcon(); if ((icon == null) && (text == null)) { return; } FontMetrics fm = g.getFontMetrics(); paintViewInsets = c.getInsets(paintViewInsets); paintViewR.x = paintViewInsets.left; paintViewR.y = paintViewInsets.top; // Use inverted height & width paintViewR.height = c.getWidth() - (paintViewInsets.left + paintViewInsets.right); paintViewR.width = c.getHeight() - (paintViewInsets.top + paintViewInsets.bottom); paintIconR.x = paintIconR.y = paintIconR.width = paintIconR.height = 0; paintTextR.x = paintTextR.y = paintTextR.width = paintTextR.height = 0; String clippedText = layoutCL(label, fm, text, icon, paintViewR, paintIconR, paintTextR); Graphics2D g2 = (Graphics2D) g; AffineTransform tr = g2.getTransform(); if (clockwise) { g2.rotate( Math.PI / 2 ); g2.translate( 0, - c.getWidth() ); } else { g2.rotate( - Math.PI / 2 ); g2.translate( - c.getHeight(), 0 ); } if (icon != null) { icon.paintIcon(c, g, paintIconR.x, paintIconR.y); } if (text != null) { int textX = paintTextR.x; int textY = paintTextR.y + fm.getAscent(); if (label.isEnabled()) { paintEnabledText(label, g, clippedText, textX, textY); } else { paintDisabledText(label, g, clippedText, textX, textY); } } g2.setTransform( tr ); } } |
