conversations-classic/src/main/java/eu/siacs/conversations/utils/StylingHelper.java
2017-11-07 23:28:14 +01:00

131 lines
4.7 KiB
Java

/*
* Copyright (c) 2017, Daniel Gultsch All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation and/or
* other materials provided with the distribution.
*
* 3. Neither the name of the copyright holder nor the names of its contributors
* may be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package eu.siacs.conversations.utils;
import android.graphics.Color;
import android.graphics.Typeface;
import android.support.annotation.ColorInt;
import android.text.Editable;
import android.text.ParcelableSpan;
import android.text.Spanned;
import android.text.TextWatcher;
import android.text.style.ForegroundColorSpan;
import android.text.style.StrikethroughSpan;
import android.text.style.StyleSpan;
import android.text.style.TypefaceSpan;
import android.widget.EditText;
import java.util.Arrays;
import java.util.List;
import eu.siacs.conversations.ui.text.QuoteSpan;
public class StylingHelper {
private static List<? extends Class<? extends ParcelableSpan>> SPAN_CLASSES = Arrays.asList(
StyleSpan.class,
StrikethroughSpan.class,
TypefaceSpan.class,
ForegroundColorSpan.class
);
public static void clear(final Editable editable) {
final int end = editable.length() - 1;
for (Class<? extends ParcelableSpan> clazz : SPAN_CLASSES) {
for (ParcelableSpan span : editable.getSpans(0, end, clazz)) {
editable.removeSpan(span);
}
}
}
public static void format(final Editable editable, @ColorInt int textColor) {
for (ImStyleParser.Style style : ImStyleParser.parse(editable)) {
final int keywordLength = style.getKeyword().length();
editable.setSpan(createSpanForStyle(style), style.getStart() + keywordLength, style.getEnd() - keywordLength + 1, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
makeKeywordOpaque(editable, style.getStart(), style.getStart() + keywordLength, textColor);
makeKeywordOpaque(editable, style.getEnd() - keywordLength + 1, style.getEnd() + 1, textColor);
}
}
private static ParcelableSpan createSpanForStyle(ImStyleParser.Style style) {
switch (style.getKeyword()) {
case "*":
return new StyleSpan(Typeface.BOLD);
case "_":
return new StyleSpan(Typeface.ITALIC);
case "~":
return new StrikethroughSpan();
case "`":
case "```":
return new TypefaceSpan("monospace");
default:
throw new AssertionError("Unknown Style");
}
}
private static void makeKeywordOpaque(final Editable editable, int start, int end, @ColorInt int fallbackTextColor) {
QuoteSpan[] quoteSpans = editable.getSpans(start, end, QuoteSpan.class);
@ColorInt int textColor = quoteSpans.length > 0 ? quoteSpans[0].getColor() : fallbackTextColor;
@ColorInt int keywordColor = transformColor(textColor);
editable.setSpan(new ForegroundColorSpan(keywordColor), start, end, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
}
private static
@ColorInt
int transformColor(@ColorInt int c) {
return Color.argb(Math.round(Color.alpha(c) * 0.6f), Color.red(c), Color.green(c), Color.blue(c));
}
public static class MessageEditorStyler implements TextWatcher {
private final EditText mEditText;
public MessageEditorStyler(EditText editText) {
this.mEditText = editText;
}
@Override
public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
}
@Override
public void afterTextChanged(Editable editable) {
clear(editable);
format(editable, mEditText.getCurrentTextColor());
}
}
}