我有一个TextView
里面有一个SpannableString
来突出显示搜索到的词。像这样:
<TextView android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/textBox"
android:textSize="16sp"
android:paddingTop="10dp"
android:paddingLeft="20dp"
android:paddingRight="20dp"
android:lineSpacingExtra="5dp"
android:textColor="@color/TextGray"/>
可以看到,我正在使用
android:lineSpacingExtra
来给线条一个很好的间距,但是这会导致SpannableString
背景太高。我想保持两行之间的间距,但要缩短SpannableString
。这怎么可能?
最佳答案
您可以通过扩展ReplacementSpan来创建自己的跨度。在draw
方法中,可以考虑从fontSpacing
参数获得的Paint
。
这样地:
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Paint.FontMetricsInt;
import android.graphics.RectF;
import android.text.style.ReplacementSpan;
public class BetterHighlightSpan extends ReplacementSpan {
private int backgroundColor;
public BetterHighlightSpan(int backgroundColor) {
super();
this.backgroundColor = backgroundColor;
}
@Override
public int getSize(Paint paint, CharSequence text, int start, int end, FontMetricsInt fm) {
return Math.round(paint.measureText(text, start, end));
}
@Override
public void draw(Canvas canvas, CharSequence text, int start, int end, float x, int top, int y, int bottom,
Paint paint) {
// save current color
int oldColor = paint.getColor();
// calculate new bottom position considering the fontSpacing
float fontSpacing = paint.getFontSpacing();
float newBottom = bottom - fontSpacing;
// change color and draw background highlight
RectF rect = new RectF(x, top, x + paint.measureText(text, start, end), newBottom);
paint.setColor(backgroundColor);
canvas.drawRect(rect, paint);
// revert color and draw text
paint.setColor(oldColor);
canvas.drawText(text, start, end, x, y, paint);
}
}
你可以这样使用它:
TextView textView = (TextView) findViewById(R.id.textView);
SpannableStringBuilder builder = new SpannableStringBuilder("here some text and more of it");
builder.setSpan(new BetterHighlightSpan(Color.CYAN), 4, 8, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
textView.setText(builder);
我没法测试,但你可以改进。