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?
正如Jon所说，对我来说，这是最好的解决方案，你不需要在运行时设置任何文本，只使用这个自定义类HtmlTextView
public class HtmlTextView extends TextView {
public HtmlTextView(Context context) {
super(context);
}
public HtmlTextView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public HtmlTextView(Context context, AttributeSet attrs, int defStyleAttr)
{
super(context, attrs, defStyleAttr);
}
@TargetApi(21)
public HtmlTextView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
super(context, attrs, defStyleAttr, defStyleRes);
}
@Override
public void setText(CharSequence s,BufferType b){
super.setText(Html.fromHtml(s.toString()),b);
}
}
就是这样，现在只把它放在XML中
<com.fitc.views.HtmlTextView
android:id="@+id/html_TV"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/example_html" />
用你的Html字符串
<string name="example_html">
<![CDATA[
<b>Author:</b> Mr Donuthead<br/>
<b>Contact:</b> me@donut.com<br/>
<i>Donuts for life </i>
]]>
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。
