是否有可能为一个TextView内的不同文本块设置多个样式?

例如,我将文本设置如下:

tv.setText(line1 + "\n" + line2 + "\n" + word1 + "\t" + word2 + "\t" + word3);

是否可以为每个文本元素设置不同的样式?例如,行1加粗,字1斜体等。

开发者指南的常见任务和如何在Android中执行这些任务包括选择,突出显示或样式化文本部分:

// Get our EditText object. EditText vw = (EditText)findViewById(R.id.text); // Set the EditText's text. vw.setText("Italic, highlighted, bold."); // If this were just a TextView, we could do: // vw.setText("Italic, highlighted, bold.", TextView.BufferType.SPANNABLE); // to force it to use Spannable storage so styles can be attached. // Or we could specify that in the XML. // Get the EditText's internal text storage Spannable str = vw.getText(); // Create our span sections, and assign a format to each. str.setSpan(new StyleSpan(android.graphics.Typeface.ITALIC), 0, 7, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE); str.setSpan(new BackgroundColorSpan(0xFFFFFF00), 8, 19, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE); str.setSpan(new StyleSpan(android.graphics.Typeface.BOLD), 21, str.length() - 1, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);

但这使用了文本中的显式位置编号。有更干净的方法吗?


当前回答

下面是一个使用HTMLBuilder的简单方法

    myTextView.setText(new HtmlBuilder().
                    open(HtmlBuilder.Type.BOLD).
                    append("Some bold text ").
                    close(HtmlBuilder.Type.BOLD).
                    open(HtmlBuilder.Type.ITALIC).
                    append("Some italic text").
                    close(HtmlBuilder.Type.ITALIC).
                    build()
    );

结果:

一些粗体字一些斜体字

其他回答

下面是一个使用HTMLBuilder的简单方法

    myTextView.setText(new HtmlBuilder().
                    open(HtmlBuilder.Type.BOLD).
                    append("Some bold text ").
                    close(HtmlBuilder.Type.BOLD).
                    open(HtmlBuilder.Type.ITALIC).
                    append("Some italic text").
                    close(HtmlBuilder.Type.ITALIC).
                    build()
    );

结果:

一些粗体字一些斜体字

现在<b>元素已弃用。<strong>呈现为<b>, <em>呈现为<i>。

tv.setText(Html.fromHtml("<strong>bold</strong> and <em>italic</em> "));

这对我来说很好

尝试HTML . fromhtml(),并用粗体和斜体HTML标记你的文本,例如:

Spanned text = Html.fromHtml("This mixes <b>bold</b> and <i>italic</i> stuff");
textView.setText(text);

使用SpannableString是实现这一目标的好方法

我使用了几个函数使其易于应用,我将首先解释每个函数的思想,然后显示代码:

String.getAllIndexOf(pattern: String): This will search the patter on the string and return an index list of where the pattern start. Ex: given the string "abcdefabc" and I call the method passing the "abc" as the searched pattern, the method should return the list: listOf(0, 6) The is a class to receive the pattern and a list of styles (in case you desire to apply different styles to the same pattern in sequence) SpannableString.applyStyle(context: Context, vararg patternAndStyles: PatternAndStyles): This will apply the styles to the given patterns


现在,在代码上:

getAllIndexOf fun String.getAllIndexOf(pattern: String): List<Int> { val allRecordsOfText = mutableListOf<Int>() var index = 0 while(index >= 0) { val newStart = if (allRecordsOfText.isEmpty()) { 0 } else { allRecordsOfText.last() + pattern.length } index = this.subSequence(newStart, this.length).indexOf(pattern) if (index >= 0) { allRecordsOfText.add(newStart + index) } } return allRecordsOfText.toList() } Class to receive the pattern and styles @Parcelize class PatternAndStyles( val pattern: String, val styles: List<Int> ) : Parcelable applyStyle fun SpannableString.applyStyle(context: Context, vararg patternAndStyles: PatternAndStyles) { for (patternStyle in patternAndStyles.toList()) { this.toString().getAllIndexOf(patternStyle.pattern).forEachIndexed { index, start -> val end = start + patternStyle.pattern.length val styleIndex = if (patternStyle.styles.size > index) index else patternStyle.styles.size - 1 this.setSpan( TextAppearanceSpan(context, patternStyle.styles[styleIndex]), start, end, SPAN_EXCLUSIVE_EXCLUSIVE ) } } } How to use it in the end val stringToApplyStyle = "abc def abc def" val text = SpannableString(stringToApplyStyle) text.applyStyle( this.applicationContext, PatternAndStyles("abc", listOf(R.style.Style1, R.style.Style2)), PatternAndStyles("def", listOf(R.style.Style3)) ) The output:

当它被传递给样式到模式“abc”时,两者都被使用 但是在模式“def”中,第二条记录重用了列表中给出的最后一个样式

使用SpannableString而不是html标记更轻量级。它帮助我看到可视化的例子,所以这里是一个补充的答案。

这是一个单一的TextView。

// set the text
SpannableString s1 = new SpannableString("bold\n");
SpannableString s2 = new SpannableString("italic\n");
SpannableString s3 = new SpannableString("foreground color\n");
SpannableString s4 = new SpannableString("background color\n");
SpannableString s5 = new SpannableString("underline\n");
SpannableString s6 = new SpannableString("strikethrough\n");
SpannableString s7 = new SpannableString("bigger\n");
SpannableString s8 = new SpannableString("smaller\n");
SpannableString s9 = new SpannableString("font\n");
SpannableString s10 = new SpannableString("URL span\n");
SpannableString s11 = new SpannableString("clickable span\n");
SpannableString s12 = new SpannableString("overlapping spans\n");

// set the style
int flag = Spanned.SPAN_EXCLUSIVE_EXCLUSIVE;
s1.setSpan(new StyleSpan(Typeface.BOLD), 0, s1.length(), flag);
s2.setSpan(new StyleSpan(Typeface.ITALIC), 0, s2.length(), flag);
s3.setSpan(new ForegroundColorSpan(Color.RED), 0, s3.length(), flag);
s4.setSpan(new BackgroundColorSpan(Color.YELLOW), 0, s4.length(), flag);
s5.setSpan(new UnderlineSpan(), 0, s5.length(), flag);
s6.setSpan(new StrikethroughSpan(), 0, s6.length(), flag);
s7.setSpan(new RelativeSizeSpan(2), 0, s7.length(), flag);
s8.setSpan(new RelativeSizeSpan(0.5f), 0, s8.length(), flag);
s9.setSpan(new TypefaceSpan("monospace"), 0, s9.length(), flag);
s10.setSpan(new URLSpan("https://developer.android.com"), 0, s10.length(), flag);
s11.setSpan(new ClickableSpan() {
    @Override
    public void onClick(View widget) {
        Toast.makeText(getApplicationContext(), "Span clicked", Toast.LENGTH_SHORT).show();
    }
}, 0, s11.length(), flag);
s12.setSpan(new ForegroundColorSpan(Color.RED), 0, 11, flag);
s12.setSpan(new BackgroundColorSpan(Color.YELLOW), 4, s12.length(), flag);
s12.setSpan(new UnderlineSpan(), 4, 11, flag);

// build the string
SpannableStringBuilder builder = new SpannableStringBuilder();
builder.append(s1);
builder.append(s2);
builder.append(s3);
builder.append(s4);
builder.append(s5);
builder.append(s6);
builder.append(s7);
builder.append(s8);
builder.append(s9);
builder.append(s10);
builder.append(s11);
builder.append(s12);

// set the text view with the styled text
textView.setText(builder);
// enables clicking on spans for clickable span and url span
textView.setMovementMethod(LinkMovementMethod.getInstance());

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 跨度类型

这个例子最初的灵感来自这里。