当我试图理解一个新概念时，我总是发现视觉例子很有帮助。

背景颜色

SpannableString spannableString = new SpannableString("Hello World!");
BackgroundColorSpan backgroundSpan = new BackgroundColorSpan(Color.YELLOW);
spannableString.setSpan(backgroundSpan, 0, spannableString.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
textView.setText(spannableString);

前景颜色

SpannableString spannableString = new SpannableString("Hello World!");
ForegroundColorSpan foregroundSpan = new ForegroundColorSpan(Color.RED);
spannableString.setSpan(foregroundSpan, 0, spannableString.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
textView.setText(spannableString);

结合

SpannableString spannableString = new SpannableString("Hello World!");
ForegroundColorSpan foregroundSpan = new ForegroundColorSpan(Color.RED);
BackgroundColorSpan backgroundSpan = new BackgroundColorSpan(Color.YELLOW);
spannableString.setSpan(foregroundSpan, 0, 8, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
spannableString.setSpan(backgroundSpan, 3, spannableString.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
textView.setText(spannableString);

进一步的研究

解释SPAN_EXCLUSIVE_EXCLUSIVE等Span标志的含义 Android Spanned, SpannedString, Spannable, SpannableString和CharSequence

设置你的TextView的文本跨度，并为你的文本定义一个ForegroundColorSpan。

TextView textView = (TextView)findViewById(R.id.mytextview01);    
Spannable wordtoSpan = new SpannableString("I know just how to whisper, And I know just how to cry,I know just where to find the answers");          
wordtoSpan.setSpan(new ForegroundColorSpan(Color.BLUE), 15, 30, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);    
textView.setText(wordtoSpan);

另一个答案将非常相似，但不需要设置TextView的文本两次

TextView TV = (TextView)findViewById(R.id.mytextview01);

Spannable wordtoSpan = new SpannableString("I know just how to whisper, And I know just how to cry,I know just where to find the answers");        

wordtoSpan.setSpan(new ForegroundColorSpan(Color.BLUE), 15, 30, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);

TV.setText(wordtoSpan);

您可以在Kotlin中使用扩展函数

fun CharSequence.colorizeText(
    textPartToColorize: CharSequence,
    @ColorInt color: Int
): CharSequence = SpannableString(this).apply {
    val startIndexOfText = this.indexOf(textPartToColorize.toString())
    setSpan(ForegroundColorSpan(color), startIndexOfText, startIndexOfText.plus(textPartToColorize.length), 0)
}

用法:

val colorizedText = "this text will be colorized"
val myTextToColorize = "some text, $colorizedText continue normal text".colorizeText(colorizedText,ContextCompat.getColor(context, R.color.someColor))
viewBinding.myTextView.text = myTextToColorize

我也有同样的问题。 @Dano的回答绝对正确。但这对我没用。 之后，我发现问题，我已经添加ClickableSpan。它会把我的颜色改成另一种颜色(强调色)

问题

当你在ForegroundColorSpan或UnderlineSpan后添加ClickableSpan时，SpannableStringBuilder将不会改变颜色和undline。

解决方案

1. 与ClickableSpan

你可以覆盖ClickableSpan内部的updateDrawState方法。 在updateDrawState方法中，您应该删除超级回调。 之后，你应该根据需要修改你的文本绘制。

2. 没有ClickableSpan

添加ForegroundColorSpan来改变文本颜色 Add UnderlineSpan在文本中添加下划线。

First Part **Second Part should be Bold** last Part

此文本应该使用SpannableString进行更改

import android.graphics.Typeface.BOLD
import android.text.Spannable
import android.text.Spannable.SPAN_EXCLUSIVE_EXCLUSIVE
import android.text.SpannableString
import android.text.style.BackgroundColorSpan
import android.text.style.ForegroundColorSpan
import android.text.style.StyleSpan

val firstPart = "First Part  "
val secondPart = "Second Part should be Bold"
val thirdPart = "  last Part"
val finalString = firstPart + secondPart + thirdPart

val sb: Spannable = SpannableString(finalString).also {
                // ... Change text Colour
                it.setSpan(
                    ForegroundColorSpan(getColor(requireContext(), R.color.pink)),
                    finalString.indexOf(secondPart),
                    finalString.indexOf(secondPart) + secondPart.length,
                    SPAN_EXCLUSIVE_EXCLUSIVE
                )
                // ... Make the text Bold
                it.setSpan(
                    StyleSpan(BOLD),
                    finalString.indexOf(secondPart),
                    finalString.indexOf(secondPart) + secondPart.length,
                    SPAN_EXCLUSIVE_EXCLUSIVE
                )
                // ... Change Background Colour
                it.setSpan(
                    BackgroundColorSpan(getColor(requireContext(), R.color.lightPink)),
                    finalString.indexOf(secondPart) - 1,
                    finalString.indexOf(secondPart) + secondPart.length + 1,
                    SPAN_EXCLUSIVE_EXCLUSIVE
                )
}

yourTextView.text = sb