我正在尝试在TextView / EditText中格式化Hashtags(比如Material Design Specs中提到的Chips).我可以使用ReplacementSpan格式化背景.但问题是我无法增加TextView / EditText中的行间距.见下图
/**
* First draw a rectangle
* Then draw text on top
*/
@Override
public void draw(Canvas canvas,CharSequence text,int start,int end,float x,int top,int y,int bottom,Paint paint) {
RectF rect = new RectF(x,top,x + measureText(paint,text,start,end),bottom);
paint.setColor(backgroundColor);
canvas.drawRoundRect(rect,CORNER_RADIUS,paint);
paint.setColor(textColor);
canvas.drawText(text,end,x,y,paint);
}
最佳答案
我不久前遇到过类似的问题,这是我提出的解决方案：
在xml中托管TextView：
viewmodel.renderedTagBadges}">
ReplacementSpan的自定义版本
public class TagBadgeSpannable extends ReplacementSpan implements LineHeightSpan {
private static int CORNER_RADIUS = 30;
private final int textColor;
private final int backgroundColor;
private final int lineHeight;
public TagBadgeSpannable(int lineHeight,int textColor,int backgroundColor) {
super();
this.textColor = textColor;
this.backgroundColor = backgroundColor;
this.lineHeight = lineHeight;
}
@Override
public void draw(Canvas canvas,Paint paint) {
final float textSize = paint.getTextSize();
final float textLength = x + measureText(paint,end);
final float badgeHeight = textSize * 2.25f;
final float textOffsetVertical = textSize * 1.45f;
RectF badge = new RectF(x,textLength,y + badgeHeight);
paint.setColor(backgroundColor);
canvas.drawRoundRect(badge,paint);
paint.setColor(textColor);
canvas.drawText(text,y + textOffsetVertical,paint);
}
@Override
public int getSize(Paint paint,Paint.FontMetricsInt fm) {
return Math.round(paint.measureText(text,end));
}
private float measureText(Paint paint,int end) {
return paint.measureText(text,end);
}
@Override
public void chooseHeight(CharSequence charSequence,int i,int i1,int i2,int i3,Paint.FontMetricsInt fontMetricsInt) {
fontMetricsInt.bottom += lineHeight;
fontMetricsInt.descent += lineHeight;
}
}
最后是一个创建Spannable的构建器
public class AndroidTagBadgeBuilder implements TagBadgeBuilder {
private final SpannableStringBuilder stringBuilder;
private final String textColor;
private final int lineHeight;
public AndroidTagBadgeBuilder(SpannableStringBuilder stringBuilder,int lineHeight,String textColor) {
this.stringBuilder = stringBuilder;
this.lineHeight = lineHeight;
this.textColor = textColor;
}
@Override
public void appendTag(String tagName,String badgeColor) {
final String nbspSpacing = "\u202F\u202F"; // none-breaking spaces
String badgeText = nbspSpacing + tagName + nbspSpacing;
stringBuilder.append(badgeText);
stringBuilder.setSpan(
new TagBadgeSpannable(lineHeight,Color.parseColor(textColor),Color.parseColor(badgeColor)),stringBuilder.length() - badgeText.length(),stringBuilder.length()- badgeText.length() + badgeText.length(),Spanned.SPAN_EXCLUSIVE_EXCLUSIVE
);
stringBuilder.append(" ");
}
@Override
public CharSequence getTags() {
return stringBuilder;
}
@Override
public void clear() {
stringBuilder.clear();
stringBuilder.clearSpans();
}
}
结果将如下所示：
根据自己的喜好调整TagBadgeSpannable中的度量.
我已经使用此代码上传了一个非常小的示例项目到github,所以请随时查看.
注意：该示例使用Android Databinding并编写MVVM样式
