DefaultLabel.java

DefaultLabel.java

package com.nutiteq.ui;

import java.util.LinkedList;
import java.util.List;

import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Paint.Align;
import android.graphics.Paint.Style;
import android.graphics.Path;
import android.graphics.Rect;
import android.graphics.RectF;

import com.nutiteq.components.TextureInfo;
import com.nutiteq.style.LabelStyle;

/**
 * Simple text-based map label containing title and optional description.
 */
public class DefaultLabel extends Label {
  private static final LabelStyle DEFAULT_STYLE = LabelStyle.builder().build();

  private final String title;
  private final String description;
  private final LabelStyle style;

  private Paint paint = null;

  private int titleHeight;
  private int descriptionHeight;
  private int descriptionWidth;

  private int width;
  private int height;

  /**
   * Default constructor.
   * 
   * @param title
   *          label title.
   */
  public DefaultLabel(String title) {
    this(title, null);
  }

  /**
   * Constructor for label with both title and description. Description will be aligned to
   * the center of the label.
   * 
   * @param title
   *          label title.
   * @param description
   *          label description. Description supports \n separator for multiline texts.
   */
  public DefaultLabel(String title, String description) {
    this(title, description, DEFAULT_STYLE);
  }

  /**
   * Constructor for label with both title and description and description alignment style.
   * 
   * @param title
   *          label title.
   * @param description
   *          label description. Description supports \n separator for multiline texts.
   * @param descAlign
   *          description alignment style.
   */
  public DefaultLabel(String title, String description, Align descAlign) {
    this(title, description, LabelStyle.builder().setDescriptionAlign(descAlign).build());
  }

  /**
   * Constructor for label with title, description and custom label style.
   * 
   * @param title
   *          label title.
   * @param description
   *          label description. Description supports \n separator for multiline texts.
   * @param style
   *          label style.
   */
  public DefaultLabel(String title, String description, LabelStyle style) {
    this.title = title;
    this.description = description;
    this.style = style;
  }
  
  /**
   * Get label title.
   * 
   * @return label title.
   */
  public String getTitle() {
    return title;
  }

  /**
   * Get label description.
   * 
   * @return label description.
   */
  public String getDescription() {
    return description;
  }

  private void initializePaint() {
    paint = new Paint(Paint.ANTI_ALIAS_FLAG);
    paint.setTextAlign(style.descriptionAlign);
    paint.setStyle(Style.FILL);

    paint.setTypeface(style.titleFont);
    paint.setTextSize(style.titleSize);

    Rect titleSize = new Rect();
    paint.getTextBounds(title, 0, title.length(), titleSize);
    titleHeight = titleSize.height();

    if (description != null && description.length()>0) {
      paint.setTypeface(style.descriptionFont);
      paint.setTextSize(style.descriptionSize);

      String[] lines = wrapText(description, paint, style.descriptionWrapWidth, 0);
      Rect lineSize = new Rect();
      int descWidth = 0, descHeight = 0;
      for (String line : lines) {
        if (line.length() == 0) {
          line = " "; // HACKFIX: getTextBounds does not work with empty strings
        }
        paint.getTextBounds(line, 0, line.length(), lineSize);
        descHeight += lineSize.height();
        descWidth = Math.max(descWidth, lineSize.width());
      }

      descriptionHeight = descHeight;
      descriptionWidth = descWidth;
      width = (int) Math.max(titleSize.width(), descriptionWidth) + 2 * style.edgePadding;
      height = (int) titleSize.height() + descriptionHeight + 2 * style.edgePadding + lines.length * style.linePadding;
    } else {
      descriptionHeight = 0;
      descriptionWidth = 0;
      width = (int) titleSize.width() + 2 * style.edgePadding;
      height = (int) titleSize.height() + 2 * style.edgePadding;
    }
  }

  @Override
  public TextureInfo drawMarkerLabel() {
    if (paint == null) {
      initializePaint();
    }

    TextureInfo textureInfo = getTextureInfo(width, height + Math.max(0, style.triangleSize - style.borderSize));
    Canvas canvas = new Canvas(textureInfo.bitmap);

    // Draw background bubble
    paint.setColor(style.borderColor);
    canvas.drawRoundRect(new RectF(0, 0, width, height), style.roundedOutside, style.roundedOutside, paint);
    paint.setColor(style.backgroundColor);
    canvas.drawRoundRect(new RectF(style.borderSize, style.borderSize, width - style.borderSize, height - style.borderSize),
        style.roundedInside, style.roundedInside, paint);

    // Draw triangle
    Path triangleOutside = new Path();
    triangleOutside.moveTo(0, 0);
    triangleOutside.lineTo(style.triangleSize, 0);
    triangleOutside.lineTo(style.triangleSize / 2, style.triangleSize);
    triangleOutside.lineTo(0, 0);

    float newBorderSize = (int) (style.borderSize * 1.4);
    Path triangleInside = new Path();
    triangleInside.moveTo(newBorderSize, 0);
    triangleInside.lineTo(style.triangleSize - newBorderSize, 0);
    triangleInside.lineTo(style.triangleSize / 2, style.triangleSize - newBorderSize * 1.5f);
    triangleInside.lineTo(newBorderSize, 0);

    canvas.translate(width / 2 - style.triangleSize / 2, height - style.borderSize);
    paint.setColor(style.borderColor);
    canvas.drawPath(triangleOutside, paint);
    paint.setColor(style.backgroundColor);
    canvas.drawPath(triangleInside, paint);
    canvas.setMatrix(null);

    // Draw text
    paint.setColor(style.titleColor);
    paint.setTypeface(style.titleFont);
    paint.setTextSize(style.titleSize);
    Align align = paint.getTextAlign();
    paint.setTextAlign(style.titleAlign);
    canvas.drawText(title, width / 2, style.edgePadding + titleHeight, paint);
    paint.setTextAlign(align);
    if (description != null) {
      paint.setColor(style.descriptionColor);
      paint.setTypeface(style.descriptionFont);
      paint.setTextSize(style.descriptionSize);
      int x = style.edgePadding;
      if (Align.CENTER.equals(paint.getTextAlign())) {
        x = width / 2;
      } else if (Align.RIGHT.equals(paint.getTextAlign())) {
        x = width - style.edgePadding;
      }
      drawString(canvas, paint, description, x, style.edgePadding + titleHeight);
    }

    return textureInfo;
  }
  
  @Override
  public float getMarkerLabelAlpha() {
    return style.alpha;
  }

  private void drawString(Canvas canvas, Paint paint, String str, int x, int y) {
    Rect bounds = new Rect();
    String[] lines = wrapText(str, paint, style.descriptionWrapWidth, 0);

    int yoff = 0;
    for (String line : lines) {
      if (line.length() == 0) {
        line = " "; // HACKFIX: getTextBounds does not work with empty strings
      }
      paint.getTextBounds(line, 0, line.length(), bounds);
      yoff += bounds.height() + style.linePadding;
      canvas.drawText(line, x, y + yoff, paint);
    }
  }

  private static String[] wrapText(String text, Paint paint, int wrapWidth, int currentX) {
    // wrapped text lines
    final List<String> wt = new LinkedList<String>();
    final int len = text.length();
    if (len == 0) {
      return new String[0];
    }

    int first = 0;
    int last = 0;
    boolean emptylineflag = false;
    for (int i = 0; i < len; i++) {
      // split at '\n'
      if (text.charAt(i) == '\n') {
        wt.add(text.substring(first, i));
        first = i + 1;
        last = i;
        emptylineflag = false;
        continue;
      }

      // update last if necessary
      if (text.charAt(i) == ' ') {
        last = i;
        // don't check to split - we would have splitted at the previous char
        continue;
      }
      
      // check that wrapping is switched on
      if (wrapWidth < 0) {
        continue;
      }

      // check length, see if we should split
      float w = paint.measureText(text, first, i + 1);
      // we should not split if we printed nothing on the previous line
      if ((first == 0 && w + currentX > wrapWidth) || (first != 0 && w > wrapWidth)) {
        // yep, we should split, first to last, then the rest
        // if last is equal to first, the first word doesn't fit, so add an
        // empty string
        // but set a flag to avoid adding it again
        if (first < last || (first == last && !emptylineflag)) {
          String s = text.substring(first, last);
          wt.add(s);
        }
        if (first < last) {
          // start with last+1
          emptylineflag = false;
          first = last + 1;
        } else {
          emptylineflag = true;
        }
      }
    }

    // add the last string
    wt.add(text.substring(first));
    return wt.toArray(new String[wt.size()]);
  }
}