这是解决方案

TextView questionValue = (TextView) findViewById(R.layout.TextView01);
questionValue.setTypeface(null, Typeface.BOLD);

最好的方法是:

TextView tv = findViewById(R.id.textView);
tv.setTypeface(Typeface.DEFAULT_BOLD);

4种方法使Android TextView粗体-完整的答案在这里。

Using android:textStyle attribute <TextView android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="TEXTVIEW 1" android:textStyle="bold" /> Use bold|italic for bold and italic. using setTypeface() method textview2.setTypeface(null, Typeface.BOLD); textview2.setText("TEXTVIEW 2"); HtmlCompat.fromHtml() method, Html.fromHtml() was deprecated in API level 24. String html="This is <b>TEXTVIEW 3</b>"; textview3.setText(HtmlCompat.fromHtml(html,Typeface.BOLD));

textView.setPaintFlags(textView.getPaintFlags() | Paint.FAKE_BOLD_TEXT_FLAG)

要移除，请使用

textView.setPaintFlags(textView.getPaintFlags() & ~Paint.FAKE_BOLD_TEXT_FLAG)

或者用Kotlin:

fun TextView.makeBold() {
    this.paintFlags = this.paintFlags or Paint.FAKE_BOLD_TEXT_FLAG
}

fun TextView.removeBold() {
    this.paintFlags = this.paintFlags and (Paint.FAKE_BOLD_TEXT_FLAG.inv())
}

你可以这样做

ty.setTypeface(Typeface.createFromAsset(ctx.getAssets(), "fonts/magistral.ttf"), Typeface.BOLD);

在XML中

android:textStyle="bold" //only bold
android:textStyle="italic" //only italic
android:textStyle="bold|italic" //bold & italic

你只能使用特定的字体sans, serif和monospace通过xml, Java代码可以使用自定义字体

android:typeface="monospace" // or sans or serif

以编程方式(Java代码)

TextView textView = (TextView) findViewById(R.id.TextView1);

textView.setTypeface(Typeface.SANS_SERIF); //only font style
textView.setTypeface(null,Typeface.BOLD); //only text style(only bold)
textView.setTypeface(null,Typeface.BOLD_ITALIC); //only text style(bold & italic)
textView.setTypeface(Typeface.SANS_SERIF,Typeface.BOLD); 
                                         //font style & text style(only bold)
textView.setTypeface(Typeface.SANS_SERIF,Typeface.BOLD_ITALIC);
                                         //font style & text style(bold & italic)