/*
* Copyright (c) 2014-2017 Sean Liu.
*
* 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 com.github.baoti.pioneer.misc.util;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffXfermode;
import android.graphics.Rect;
import android.graphics.Xfermode;
import android.graphics.drawable.shapes.Shape;
import android.support.annotation.ColorInt;
import android.support.annotation.IntRange;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.text.TextPaint;
import android.text.style.CharacterStyle;
import android.text.style.MetricAffectingSpan;
import android.text.style.ReplacementSpan;
import android.text.style.UnderlineSpan;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
/**
* text span 工具类，提供可组合使用的 ReplacementSpan 实例。
* <br>可用于实现 绘制带圆角矩形背景的文字，甚至是绘制镂空的文字
* <br>NOTE:
* 按照 {@link android.text.BoringLayout} 与 {@literal android.text.TextLine} 的设计，
* {@literal <ReplacementSpan>1+2=<u>3</u></ReplacementSpan>} 中的{@literal <u>3</u>} 对应的{@link UnderlineSpan}是不生效的。
*
* Created by sean on 2017/10/1.
*/
public class Spans {
/**
* 自定义 ReplacementSpan 基类，回调方法新增 outRect 参数，接收外层 span 的尺寸
*/
public static class SupportSpan extends ReplacementSpan {
protected final Paint.FontMetricsInt fontMetricsInt = new Paint.FontMetricsInt();
protected final Rect frame = new Rect();
private int fixedWidth = -1;
@Override
public final int getSize(@NonNull Paint paint, CharSequence text, @IntRange(from = 0) int start, @IntRange(from = 0) int end, @Nullable Paint.FontMetricsInt fm) {
return getSize(frame, paint, text, start, end, fm);
}
@Override
public final void draw(@NonNull Canvas canvas, CharSequence text, @IntRange(from = 0) int start, @IntRange(from = 0) int end, float x, int top, int y, int bottom, @NonNull Paint paint) {
draw(frame, canvas, text, start, end, x, top, y, bottom, paint);
}
public int getSize(@NonNull Rect outRect, @NonNull Paint paint, CharSequence text, @IntRange(from = 0) int start, @IntRange(from = 0) int end, @Nullable Paint.FontMetricsInt fm) {
return getMinSize(outRect, paint, text, start, end, fm);
}
public int getMinSize(@NonNull Rect outRect, @NonNull Paint paint, CharSequence text, @IntRange(from = 0) int start, @IntRange(from = 0) int end, @Nullable Paint.FontMetricsInt fm) {
if (fm != null) {
paint.getFontMetricsInt(fm);
}
int width = fixedWidth >= 0 ? fixedWidth : (int) Math.ceil(paint.measureText(text, start, end));
paint.getFontMetricsInt(fontMetricsInt);
frame.right = width;
frame.top = fontMetricsInt.top;
frame.bottom = fontMetricsInt.bottom;
return width;
}
public void draw(@NonNull Rect outRect, @NonNull Canvas canvas, CharSequence text, @IntRange(from = 0) int start, @IntRange(from = 0) int end, float x, int top, int y, int bottom, @NonNull Paint paint) {
}
public int getFixedWidth() {
return fixedWidth;
}
public void setFixedWidth(int fixedWidth) {
this.fixedWidth = fixedWidth;
}
}
/**
* 可嵌套使用的 ReplacementSpan，支持接收其他 CharacterStyle 作为内层 span 并产生对应效果
*/
public static class SpanGroup extends SupportSpan {
private final List<CharacterStyle> styles;
public SpanGroup(CharacterStyle... styles) {
this.styles = new ArrayList<>(styles.length);
Collections.addAll(this.styles, styles);
}
@Override
public int getSize(@NonNull Rect outRect, @NonNull Paint paint, CharSequence text, @IntRange(from = 0) int start, @IntRange(from = 0) int end, @Nullable Paint.FontMetricsInt fm) {
int width = super.getSize(outRect, paint, text, start, end, fm);
if (styles != null) {
for (CharacterStyle style : styles) {
if (style instanceof SupportSpan) {
width = Math.max(width, ((SupportSpan) style).getSize(frame, paint, text, start, end, fm));
} else if (style instanceof ReplacementSpan) {
width = Math.max(width, ((ReplacementSpan) style).getSize(paint, text, start, end, fm));
} else if (paint instanceof TextPaint) {
if (style instanceof MetricAffectingSpan) {
((MetricAffectingSpan) style).updateMeasureState((TextPaint) paint);
}
}
}
}
frame.right = width;
return width;
}
@Override
public void draw(@NonNull Rect outRect, @NonNull Canvas canvas, CharSequence text, @IntRange(from = 0) int start, @IntRange(from = 0) int end, float x, int top, int y, int bottom, @NonNull Paint paint) {
for (CharacterStyle style : styles) {
if (style instanceof SupportSpan) {
((SupportSpan) style).draw(frame, canvas, text, start, end, x, top, y, bottom, paint);
} else if (style instanceof ReplacementSpan) {
((ReplacementSpan) style).draw(canvas, text, start, end, x, top, y, bottom, paint);
} else if (paint instanceof TextPaint) {
style.updateDrawState((TextPaint) paint);
}
}
}
}
/**
* 文本绘制，用于与 ReplacementSpan 组合。
* <br>因为 TextLine 默认不会为 ReplacementSpan 绘文字
*/
public static class TextSpan extends SpanGroup {
private final Paint.Align align;
private final Paint.Style style;
private final float strokeWidth;
public TextSpan(CharacterStyle... styles) {
this(null, styles);
}
public TextSpan(Paint.Align align, CharacterStyle... styles) {
this(align, null, 0, styles);
}
public TextSpan(Paint.Align align, Paint.Style style, float strokeWidth, CharacterStyle... styles) {
super(styles);
this.align = align;
this.strokeWidth = strokeWidth;
this.style = style;
}
@Override
public void draw(@NonNull Rect outRect, @NonNull Canvas canvas, CharSequence text, @IntRange(from = 0) int start, @IntRange(from = 0) int end, float x, int top, int y, int bottom, @NonNull Paint paint) {
Paint.Align oldAlign = paint.getTextAlign();
Paint.Style oldStyle = paint.getStyle();
float oldStrokeWidth = paint.getStrokeWidth();
if (align != null) {
paint.setTextAlign(align);
}
if (style != null) {
paint.setStyle(style);
}
if (strokeWidth > 0) {
paint.setStrokeWidth(strokeWidth);
}
super.draw(outRect, canvas, text, start, end, x, top, y, bottom, paint);
switch (paint.getTextAlign()) {
case CENTER:
canvas.drawText(text, start, end, x + (outRect.right - outRect.left) / 2, y, paint);
break;
default:
canvas.drawText(text, start, end, x, y, paint);
break;
}
paint.setTextAlign(oldAlign);
paint.setStyle(oldStyle);
paint.setStrokeWidth(oldStrokeWidth);
}
}
/**
* 镂空绘制样式
* <br>注意：不支持在该文本内再进行span分块，
* 如：{@literal <Hollow>ABC<fgcolor>DE</fgcolor></Hollow>}，
* 可改为：{@literal <Hollow>ABC</Hollow><Hollow><fgcolor>DE</fgcolor></Hollow>}
*/
public static class HollowSpan extends SpanGroup {
private final SpanGroup srcGroup;
private final PorterDuffXfermode xfermode = new PorterDuffXfermode(PorterDuff.Mode.DST_OUT);
private Bitmap bitmap;
private Canvas bitmapCanvas;
/**
* 镂空绘制
* @param styles 基础样式
* @param srcStyles 镂空样式
*/
public HollowSpan(CharacterStyle[] styles, CharacterStyle[] srcStyles) {
super(styles);
this.srcGroup = new SpanGroup(srcStyles);
}
/**
* 镂空绘制
* @param styles 基础样式
* @param srcGroup 镂空样式
*/
public HollowSpan(CharacterStyle[] styles, SpanGroup srcGroup) {
super(styles);
this.srcGroup = srcGroup;
}
@Override
public int getSize(@NonNull Rect outRect, @NonNull Paint paint, CharSequence text, @IntRange(from = 0) int start, @IntRange(from = 0) int end, @Nullable Paint.FontMetricsInt fm) {
int width = super.getSize(outRect, paint, text, start, end, fm);
srcGroup.getSize(outRect, paint, text, start, end, fm);
return width;
}
@Override
public void draw(@NonNull Rect outRect, @NonNull Canvas canvas, CharSequence text, @IntRange(from = 0) int start, @IntRange(from = 0) int end, float x, int top, int y, int bottom, @NonNull Paint paint) {
if (bitmap == null) {
bitmap = Bitmap.createBitmap(frame.right - frame.left, frame.bottom - frame.top, Bitmap.Config.ARGB_8888);
bitmapCanvas = new Canvas(bitmap);
}
bitmapCanvas.drawColor(Color.BLACK, PorterDuff.Mode.CLEAR);
bitmapCanvas.translate(-x, 0);
super.draw(outRect, bitmapCanvas, text, start, end, x, top, y, bottom, paint);
Xfermode oldXfermode = paint.getXfermode();
paint.setXfermode(this.xfermode);
srcGroup.draw(outRect, bitmapCanvas, text, start, end, x, top, y, bottom, paint);
paint.setXfermode(oldXfermode);
canvas.drawBitmap(bitmap, x, 0, null);
}
}
/**
* 调试绘制，画 top/bottom/ascent/descent 位置的线
*/
public static class DebugSpan extends SpanGroup {
public DebugSpan(CharacterStyle... styles) {
super(styles);
}
@Override
public void draw(@NonNull Rect outRect, @NonNull Canvas canvas, CharSequence text, @IntRange(from = 0) int start, @IntRange(from = 0) int end, float x, int top, int y, int bottom, @NonNull Paint paint) {
drawDebugLines(outRect, canvas, x, top, y, bottom, paint);
super.draw(outRect, canvas, text, start, end, x, top, y, bottom, paint);
}
protected void drawDebugLines(Rect outRect, @NonNull Canvas canvas, float x, int top, int y, int bottom, @NonNull Paint paint) {
int width = frame.width();
int oldColor = paint.getColor();
// x, y
canvas.drawLine(x, y, x + width, y, paint);
// x, top
paint.setColor(Color.RED);
canvas.drawLine(x, top, x + width, top, paint);
canvas.drawLine(x, y + fontMetricsInt.top, x + width, bottom, paint);
// x, ascent
paint.setColor(Color.GREEN);
canvas.drawLine(x, y + paint.ascent(), x + width, bottom, paint);
canvas.drawLine(x, y + fontMetricsInt.ascent, x + width, y + fontMetricsInt.ascent, paint);
// x, descent
paint.setColor(Color.BLUE);
canvas.drawLine(x, y + paint.descent(), x + width, top, paint);
canvas.drawLine(x, y + fontMetricsInt.descent, x + width, y + fontMetricsInt.descent, paint);
// x, bottom
paint.setColor(Color.YELLOW);
canvas.drawLine(x, bottom, x + width, bottom, paint);
canvas.drawLine(x, y + fontMetricsInt.bottom, x + width, top, paint);
paint.setColor(oldColor);
}
}
/**
* 图形绘制，可使用 Shape 绘制图形，如：圆角矩形
*/
public static class ShapeSpan extends SpanGroup {
private final Shape shape;
private final Paint.Style style;
private final int strokeWidth;
@ColorInt
private final int color;
private final boolean includePad; // true：高度为 bottom - top，false：高度为 descent - ascent
public ShapeSpan(Shape shape, Paint.Style style, int strokeWidth, @ColorInt int color, boolean includePad, CharacterStyle... styles) {
super(styles);
this.shape = shape;
this.style = style;
this.strokeWidth = strokeWidth;
this.color = color;
this.includePad = includePad;
}
@Override
public int getSize(@NonNull Rect outRect, @NonNull Paint paint, CharSequence text, @IntRange(from = 0) int start, @IntRange(from = 0) int end, @Nullable Paint.FontMetricsInt fm) {
int width = super.getSize(outRect, paint, text, start, end, fm);
if (includePad) {
shape.resize(frame.right - strokeWidth, fontMetricsInt.bottom - fontMetricsInt.top - strokeWidth);
} else {
shape.resize(frame.right - strokeWidth, fontMetricsInt.descent - fontMetricsInt.ascent - strokeWidth);
}
return width;
}
@Override
public void draw(@NonNull Rect outRect, @NonNull Canvas canvas, CharSequence text, @IntRange(from = 0) int start, @IntRange(from = 0) int end, float x, int top, int y, int bottom, @NonNull Paint paint) {
float oldStrokeWidth = paint.getStrokeWidth();
Paint.Style oldStyle = paint.getStyle();
int oldColor = paint.getColor();
paint.setStrokeWidth(strokeWidth);
paint.setStyle(style);
paint.setColor(color);
canvas.save();
if (includePad) {
canvas.translate(x + strokeWidth / 2, strokeWidth / 2);
} else {
canvas.translate(x + strokeWidth / 2, fontMetricsInt.ascent - fontMetricsInt.top + strokeWidth / 2);
}
shape.draw(canvas, paint);
canvas.restore();
paint.setColor(oldColor);
paint.setStyle(oldStyle);
paint.setStrokeWidth(oldStrokeWidth);
float oldTextSize = paint.getTextSize();
paint.setTextSize(oldTextSize * 0.8f);
super.draw(outRect, canvas, text, start, end, x, top, y, bottom, paint);
paint.setTextSize(oldTextSize);
}
}
}
