platform/platform-api/src/com/intellij/ui/ErrorLabel.java

   1 /*
   2  * Copyright 2000-2009 JetBrains s.r.o.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 package com.intellij.ui;
  17
  18 import javax.swing.*;
  19 import java.awt.*;
  20
  21 /**
  22  * @author kir
  23  */
  24 public class ErrorLabel extends JLabel {
  25
  26   private boolean myUnderline;
  27
  28   private Color myForeground;
  29   private String myTooltip;
  30
  31   public ErrorLabel() {
  32     this(null, null);
  33   }
  34
  35   public ErrorLabel(String text) {
  36     this(text, null);
  37   }
  38
  39   public ErrorLabel(String text, Icon icon) {
  40     super(text, icon, JLabel.LEFT);
  41     setOpaque(false);
  42   }
  43
  44   public void setErrorText(String text, Color color) {
  45     boolean newUnderline = text != null;
  46     myForeground = color;
  47     if (newUnderline) {
  48       updateLabelView(newUnderline, text);
  49     }
  50     else if (myUnderline) {
  51       updateLabelView(newUnderline, myTooltip);
  52     }
  53   }
  54
  55   public void setToolTipText(String text) {
  56     if (myUnderline) {
  57       myTooltip = text;
  58     }
  59     else {
  60       super.setToolTipText(text);
  61     }
  62   }
  63
  64
  65
  66   private void updateLabelView(boolean newUnderline, String tooltip) {
  67     super.setToolTipText(tooltip);
  68     myUnderline = newUnderline;
  69     repaint();
  70   }
  71
  72   protected void paintComponent(Graphics g) {
  73
  74     super.paintComponent(g);
  75
  76     if (getText() != null & myUnderline) {
  77       g.setColor(myForeground);
  78       int x = 0;
  79
  80       if (getIcon() != null) {
  81         x = getIcon().getIconWidth() + getIconTextGap();
  82       }
  83
  84       if (getHorizontalAlignment() == CENTER) {
  85         int w = g.getFontMetrics().stringWidth(getText());
  86         x += (getWidth() - x - w) >> 1;
  87       }
  88
  89       drawWave(this, g, x, getText());
  90     }
  91   }
  92
  93   public static void drawWave(Component c, Graphics g, int x, String text) {
  94     int y = getTextBaseLine(c);
  95
  96     y += 2;
  97
  98     int width = c.getFontMetrics(c.getFont()).stringWidth(text);
  99     int nLines = (width >> 1) + 1;
 100
 101     int xCurr = x;
 102     int yBottom = y + 1;
 103     int []xx = new int[nLines + 1];
 104     int []yy = new int[nLines + 1];
 105     int line = 0;
 106     for (; line < nLines; line += 2) {
 107       xx[line] = xCurr;
 108       yy[line] = yBottom;
 109
 110       xx[line + 1] = xCurr + 2;
 111       yy[line + 1] = yBottom - 2;
 112       xCurr += 4;
 113     }
 114
 115     g.drawPolyline(xx, yy, line);
 116   }
 117
 118   private static int getTextBaseLine(Component c) {
 119     FontMetrics fm = c.getFontMetrics(c.getFont());
 120     return (c.getHeight() >> 1) + ((fm.getHeight() >> 1) - fm.getDescent());
 121   }
 122 }