+ * A {@link TextView} that insert spaces around its text spans where needed to
+ * prevent {@link IndexOutOfBoundsException} in {@link #onMeasure(int, int)} on
+ * Jelly Bean.
+ *
+ * When {@link #onMeasure(int, int)} throws an exception, we try to fix the text
+ * by adding spaces around spans, until it works again. We then try removing
+ * some of the added spans, to minimize the insertions.
+ *
+ * The fix is time consuming (a few ms, it depends on the size of your text),
+ * but it should only happen once per text change.
+ *
+ * See http://code.google.com/p/android/issues/detail?id=35466
+ *
+ * @author "Pierre-Yves Ricau"
+ *
+ */
+public class JellyBeanSpanFixTextView extends TextView {
+
+ private static class FixingResult {
+ public final boolean fixed;
+ public final List spansWithSpacesBefore;
+ public final List spansWithSpacesAfter;
+
+ public static FixingResult fixed(List spansWithSpacesBefore, List spansWithSpacesAfter) {
+ return new FixingResult(true, spansWithSpacesBefore, spansWithSpacesAfter);
+ }
+
+ public static FixingResult notFixed() {
+ return new FixingResult(false, null, null);
+ }
+
+ private FixingResult(boolean fixed, List spansWithSpacesBefore, List spansWithSpacesAfter) {
+ this.fixed = fixed;
+ this.spansWithSpacesBefore = spansWithSpacesBefore;
+ this.spansWithSpacesAfter = spansWithSpacesAfter;
+ }
+ }
+
+ private static final String TAG = JellyBeanSpanFixTextView.class.getSimpleName();
+
+ public JellyBeanSpanFixTextView(Context context, AttributeSet attrs, int defStyle) {
+ super(context, attrs, defStyle);
+ }
+
+ public JellyBeanSpanFixTextView(Context context, AttributeSet attrs) {
+ super(context, attrs);
+ }
+
+ public JellyBeanSpanFixTextView(Context context) {
+ super(context);
+ }
+
+ @Override
+ protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
+ try {
+ super.onMeasure(widthMeasureSpec, heightMeasureSpec);
+ } catch (IndexOutOfBoundsException e) {
+ fixOnMeasure(widthMeasureSpec, heightMeasureSpec);
+ }
+ }
+
+ /**
+ * If possible, fixes the Spanned text by adding spaces around spans when
+ * needed.
+ */
+ private void fixOnMeasure(int widthMeasureSpec, int heightMeasureSpec) {
+ CharSequence text = getText();
+ if (text instanceof Spanned) {
+ SpannableStringBuilder builder = new SpannableStringBuilder(text);
+ fixSpannedWithSpaces(builder, widthMeasureSpec, heightMeasureSpec);
+ } else {
+ //if (BuildConfig.DEBUG) {
+ // Log.d(TAG, "The text isn't a Spanned");
+ //}
+ fallbackToString(widthMeasureSpec, heightMeasureSpec);
+ }
+ }
+
+ /**
+ * Add spaces around spans until the text is fixed, and then removes the
+ * unneeded spaces
+ */
+ private void fixSpannedWithSpaces(SpannableStringBuilder builder, int widthMeasureSpec, int heightMeasureSpec) {
+ long startFix = System.currentTimeMillis();
+
+ FixingResult result = addSpacesAroundSpansUntilFixed(builder, widthMeasureSpec, heightMeasureSpec);
+
+ if (result.fixed) {
+ removeUnneededSpaces(widthMeasureSpec, heightMeasureSpec, builder, result);
+ } else {
+ fallbackToString(widthMeasureSpec, heightMeasureSpec);
+ }
+
+ //if (BuildConfig.DEBUG) {
+ // long fixDuration = System.currentTimeMillis() - startFix;
+ // Log.d(TAG, "fixSpannedWithSpaces() duration in ms: " + fixDuration);
+ //}
+ }
+
+ private FixingResult addSpacesAroundSpansUntilFixed(SpannableStringBuilder builder, int widthMeasureSpec, int heightMeasureSpec) {
+
+ Object[] spans = builder.getSpans(0, builder.length(), Object.class);
+ List spansWithSpacesBefore = new ArrayList(spans.length);
+ List spansWithSpacesAfter = new ArrayList(spans.length);
+
+ for (Object span : spans) {
+ int spanStart = builder.getSpanStart(span);
+ if (isNotSpace(builder, spanStart - 1)) {
+ builder.insert(spanStart, " ");
+ spansWithSpacesBefore.add(span);
+ }
+
+ int spanEnd = builder.getSpanEnd(span);
+ if (isNotSpace(builder, spanEnd)) {
+ builder.insert(spanEnd, " ");
+ spansWithSpacesAfter.add(span);
+ }
+
+ try {
+ setTextAndMeasure(builder, widthMeasureSpec, heightMeasureSpec);
+ return FixingResult.fixed(spansWithSpacesBefore, spansWithSpacesAfter);
+ } catch (IndexOutOfBoundsException notFixed) {
+ }
+ }
+ //if (BuildConfig.DEBUG) {
+ // Log.d(TAG, "Could not fix the Spanned by adding spaces around spans");
+ //}
+ return FixingResult.notFixed();
+ }
+
+ private boolean isNotSpace(CharSequence text, int where) {
+ return text.charAt(where) != ' ';
+ }
+
+ private void setTextAndMeasure(CharSequence text, int widthMeasureSpec, int heightMeasureSpec) {
+ setText(text);
+ super.onMeasure(widthMeasureSpec, heightMeasureSpec);
+ }
+
+ private void removeUnneededSpaces(int widthMeasureSpec, int heightMeasureSpec, SpannableStringBuilder builder, FixingResult result) {
+
+ for (Object span : result.spansWithSpacesAfter) {
+ int spanEnd = builder.getSpanEnd(span);
+ builder.delete(spanEnd, spanEnd + 1);
+ try {
+ setTextAndMeasure(builder, widthMeasureSpec, heightMeasureSpec);
+ } catch (IndexOutOfBoundsException ignored) {
+ builder.insert(spanEnd, " ");
+ }
+ }
+
+ boolean needReset = true;
+ for (Object span : result.spansWithSpacesBefore) {
+ int spanStart = builder.getSpanStart(span);
+ builder.delete(spanStart - 1, spanStart);
+ try {
+ setTextAndMeasure(builder, widthMeasureSpec, heightMeasureSpec);
+ needReset = false;
+ } catch (IndexOutOfBoundsException ignored) {
+ needReset = true;
+ int newSpanStart = spanStart - 1;
+ builder.insert(newSpanStart, " ");
+ }
+ }
+
+ if (needReset) {
+ setText(builder);
+ super.onMeasure(widthMeasureSpec, heightMeasureSpec);
+ }
+ }
+
+ private void fallbackToString(int widthMeasureSpec, int heightMeasureSpec) {
+ //if (BuildConfig.DEBUG) {
+ // Log.d(TAG, "Fallback to unspanned text");
+ //}
+ String fallbackText = getText().toString();
+ setTextAndMeasure(fallbackText, widthMeasureSpec, heightMeasureSpec);
+ }
+
+}