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A TextView to prevent a bug with spans on JellyBean: http://code.google.com/p/android/issues/detail?id=35466
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// Copyright 2012 Pierre-Yves Ricau | |
// | |
// Licensed under the Apache License, Version 2.0 (the "License"); you may not | |
// use this file except in compliance with the License. You may obtain a copy of | |
// the License at | |
// | |
// http://www.apache.org/licenses/LICENSE-2.0 | |
// | |
// Unless required by applicable law or agreed to in writing, software | |
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT | |
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the | |
// License for the specific language governing permissions and limitations under | |
// the License. | |
package info.piwai.android; | |
import java.util.ArrayList; | |
import java.util.List; | |
import android.content.Context; | |
import android.text.SpannableStringBuilder; | |
import android.text.Spanned; | |
import android.util.AttributeSet; | |
import android.util.Log; | |
import android.widget.TextView; | |
/** | |
* <p> | |
* A {@link TextView} that insert spaces around its text spans where needed to | |
* prevent {@link IndexOutOfBoundsException} in {@link #onMeasure(int, int)} on | |
* Jelly Bean. | |
* <p> | |
* 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. | |
* <p> | |
* 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. | |
* <p> | |
* See http://code.google.com/p/android/issues/detail?id=35466 | |
* | |
* @author "Pierre-Yves Ricau" <[email protected]> | |
* | |
*/ | |
public class JellyBeanSpanFixTextView extends TextView { | |
private static class FixingResult { | |
public final boolean fixed; | |
public final List<Object> spansWithSpacesBefore; | |
public final List<Object> spansWithSpacesAfter; | |
public static FixingResult fixed(List<Object> spansWithSpacesBefore, List<Object> spansWithSpacesAfter) { | |
return new FixingResult(true, spansWithSpacesBefore, spansWithSpacesAfter); | |
} | |
public static FixingResult notFixed() { | |
return new FixingResult(false, null, null); | |
} | |
private FixingResult(boolean fixed, List<Object> spansWithSpacesBefore, List<Object> 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<Object> spansWithSpacesBefore = new ArrayList<Object>(spans.length); | |
List<Object> spansWithSpacesAfter = new ArrayList<Object>(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); | |
} | |
} |
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Need to fix and simplify isNotSpace() method: