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

这是一个帮助函数。当你有多种语言的时候非常有用!

private void setColor(TextView view, String fulltext, String subtext, int color) {
    view.setText(fulltext, TextView.BufferType.SPANNABLE);
    Spannable str = (Spannable) view.getText();
    int i = fulltext.indexOf(subtext);
    str.setSpan(new ForegroundColorSpan(color), i, i + subtext.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
}

只是补充一个公认的答案，因为所有的答案似乎都在谈论android.graphics.Color only:如果我想要的颜色是在res/values/colors.xml中定义的呢?

例如，考虑colors.xml中定义的材质设计颜色:

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <color name="md_blue_500">#2196F3</color>
</resources>

(android_material_design_colors .xml是你最好的朋友)

然后使用contextcompast . getcolor (getContext()， R.color.md_blue_500)，在这里您将使用Color。蓝色，所以:

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

就变成:

wordtoSpan.setSpan(new ForegroundColorSpan(ContextCompat.getColor(getContext(), R.color.md_blue_500)), 15, 30, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);

我发现:

在Android中使用跨度- Michael Spitsin - Medium

通过传递String和Color在文本上设置颜色:

private String getColoredSpanned(String text, String color) {
  String input = "<font color=" + color + ">" + text + "</font>";
  return input;
}

通过调用下面的代码设置TextView / Button / EditText等文本:

TextView:

TextView txtView = (TextView)findViewById(R.id.txtView);

获取彩色字符串:

String name = getColoredSpanned("Hiren", "#800000");

在TextView上设置文本:

txtView.setText(Html.fromHtml(name));

Done

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

从开发人员文档中，更改一个可伸缩对象的颜色和大小:

1-创建类:

    class RelativeSizeColorSpan(size: Float,@ColorInt private val color: Int): RelativeSizeSpan(size) {

    override fun updateDrawState(textPaint: TextPaint?) {
        super.updateDrawState(textPaint)
        textPaint?.color = color
    } 
}

2 .使用该类创建你的spannable:

    val spannable = SpannableStringBuilder(titleNames)
spannable.setSpan(
    RelativeSizeColorSpan(1.5f, Color.CYAN), // Increase size by 50%
    titleNames.length - microbe.name.length, // start
    titleNames.length, // end
    Spannable.SPAN_EXCLUSIVE_INCLUSIVE
)