Find string which width is optimal to the TextView and set it as text

Description

Demo Code

import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;

import android.support.annotation.ArrayRes;
import android.view.ViewTreeObserver;
import android.widget.TextView;

public class Main {
  private static final Comparator<String> lengthComparator = new Comparator<String>() {
    @Override//from   www .j a  v  a 2 s  .  com
    public int compare(String lhs, String rhs) {
      return lhs.length() - rhs.length();
    }
  };

  /**
   * Find string which width is optimal to the TextView and set it as text
   * 
   * @param textView
   *          can be not measured yet
   * @param stringArray
   *          id of string array, can be unsorted
   */
  public static void setOptimalWidthText(final TextView textView,
      @ArrayRes int stringArray) {
    setOptimalWidthText(textView, textView.getContext().getResources()
        .getStringArray(stringArray));
  }

  /**
   * Finds string which width is optimal to the TextView and set it as text
   * 
   * @param textView
   *          can be not measured yet
   * @param strings
   *          can be unsorted
   */
  public static void setOptimalWidthText(final TextView textView,
      final String... strings) {
    if (strings.length == 0) {
      textView.setText("");
    } else if (strings.length == 1) {
      textView.setText(strings[0]);
    } else {
      textView.getViewTreeObserver().addOnGlobalLayoutListener(
          new ViewTreeObserver.OnGlobalLayoutListener() {
            @Override
            public void onGlobalLayout() {
              int measuredWidth = textView.getMeasuredWidth();
              setOptimalWidthText(textView, measuredWidth, strings);
              textView.getViewTreeObserver().removeGlobalOnLayoutListener(this);
            }
          });
    }
  }

  /**
   * Finds string which width is optimal to the TextView and set it as text.
   * 
   * @param textView
   *          can be not measured yet
   * @param width
   *          value to compare with strings width
   * @param strings
   *          can be unsorted
   */
  private static void setOptimalWidthText(final TextView textView, int width,
      final String... strings) {
    textView.setText(getOptimalWidthString(textView, width, strings));
  }

  /**
   * Find string which width is optimal to the TextView.
   * 
   * @param textView
   *          can be not measured yet
   * @param width
   *          value to compare with strings width
   * @param strings
   *          can be unsorted
   * @return optimal width string from width
   */
  public static String getOptimalWidthString(final TextView textView,
      int width, final String... strings) {
    List<String> collection = Arrays.asList(strings);
    if (!isSorted(collection, lengthComparator))
      Collections.sort(collection, lengthComparator);
    Iterator<String> i = collection.iterator();
    String result = i.next();
    String current;
    while (i.hasNext() && getTextSize(textView, current = i.next()) < width) {
      result = current;
    }
    return result;
  }

  private static <T extends Comparable> boolean isSorted(Iterable<T> iterable,
      Comparator<T> comparator) {
    T previous = null;
    for (T t : iterable) {
      if (previous != null && comparator.compare(previous, t) < 0)
        return false;
      previous = t;
    }
    return true;
  }

  /**
   * Return the width of the testText.
   * 
   * @return the width of testText placed in the textView
   */
  private static float getTextSize(TextView textView, String testText) {
    return textView.getPaint().measureText(testText);
  }
}
Find string which width is optimal to the TextView and set it as text - Android User Interface

Description

Demo Code

Related Tutorials
