试试这个

TextView headerText= new TextView(getApplicationContext());
RelativeLayout.LayoutParams lp = new RelativeLayout.LayoutParams(ActionBar.LayoutParams.WRAP_CONTENT, ActionBar.LayoutParams.WRAP_CONTENT);
headerText.setLayoutParams(lp);
headerText.setText("Welcome!");
headerText.setTextSize(20);
headerText.setTextColor(Color.parseColor("#FFFFFF"));
Typeface tf = Typeface.createFromAsset(getAssets(), "fonts/wesfy_regular.ttf");
headerText.setTypeface(tf);
getSupportActionBar().setDisplayOptions(ActionBar.DISPLAY_SHOW_CUSTOM);
getSupportActionBar().setCustomView(headerText);

您可以使用自定义TypefaceSpan类来实现这一点。它优于上面提到的customView方法，因为它在使用其他操作栏元素(如展开操作视图)时不会中断。

这样一个类的使用应该是这样的:

SpannableString s = new SpannableString("My Title");
s.setSpan(new TypefaceSpan(this, "MyTypeface.otf"), 0, s.length(),
        Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);

// Update the action bar title with the TypefaceSpan instance
ActionBar actionBar = getActionBar();
actionBar.setTitle(s);

自定义TypefaceSpan类传递给您的Activity上下文和assets/fonts目录中的字体名称。它加载文件并在内存中缓存一个新的字体实例。TypefaceSpan的完整实现非常简单:

/**
 * Style a {@link Spannable} with a custom {@link Typeface}.
 * 
 * @author Tristan Waddington
 */
public class TypefaceSpan extends MetricAffectingSpan {
      /** An <code>LruCache</code> for previously loaded typefaces. */
    private static LruCache<String, Typeface> sTypefaceCache =
            new LruCache<String, Typeface>(12);

    private Typeface mTypeface;

    /**
     * Load the {@link Typeface} and apply to a {@link Spannable}.
     */
    public TypefaceSpan(Context context, String typefaceName) {
        mTypeface = sTypefaceCache.get(typefaceName);

        if (mTypeface == null) {
            mTypeface = Typeface.createFromAsset(context.getApplicationContext()
                    .getAssets(), String.format("fonts/%s", typefaceName));

            // Cache the loaded Typeface
            sTypefaceCache.put(typefaceName, mTypeface);
        }
    }

    @Override
    public void updateMeasureState(TextPaint p) {
        p.setTypeface(mTypeface);

        // Note: This flag is required for proper typeface rendering
        p.setFlags(p.getFlags() | Paint.SUBPIXEL_TEXT_FLAG);
    }

    @Override
    public void updateDrawState(TextPaint tp) {
        tp.setTypeface(mTypeface);

        // Note: This flag is required for proper typeface rendering
        tp.setFlags(tp.getFlags() | Paint.SUBPIXEL_TEXT_FLAG);
    }
}

简单地复制上面的类到你的项目中，并在你的活动的onCreate方法中实现它，如上所示。

为了补充@Sam_D的答案，我必须这样做才能使它工作:

this.setTitle("my title!");
((TextView)v.findViewById(R.id.title)).setText(this.getTitle());
TextView title = ((TextView)v.findViewById(R.id.title));
title.setEllipsize(TextUtils.TruncateAt.MARQUEE);
title.setMarqueeRepeatLimit(1);
// in order to start strolling, it has to be focusable and focused
title.setFocusable(true);
title.setSingleLine(true);
title.setFocusableInTouchMode(true);
title.requestFocus();

这似乎有点过分-两次引用v.f entviewbyid (R.id.title)) -但这是唯一的方法，它会让我这样做。

int titleId = getResources().getIdentifier("action_bar_title", "id",
            "android");
    TextView yourTextView = (TextView) findViewById(titleId);
    yourTextView.setTextColor(getResources().getColor(R.color.black));
    yourTextView.setTypeface(face);

我同意这不是完全支持的，但以下是我所做的。您可以为操作栏使用自定义视图(它将显示在图标和操作项之间)。我正在使用一个自定义视图，我已经禁用了本机标题。我所有的活动都继承自一个活动，它在onCreate中有这样的代码:

this.getActionBar().setDisplayShowCustomEnabled(true);
this.getActionBar().setDisplayShowTitleEnabled(false);

LayoutInflater inflator = LayoutInflater.from(this);
View v = inflator.inflate(R.layout.titleview, null);

//if you need to customize anything else about the text, do it here.
//I'm using a custom TextView with a custom font in my layout xml so all I need to do is set title
((TextView)v.findViewById(R.id.title)).setText(this.getTitle());

//assign the view to the actionbar
this.getActionBar().setCustomView(v);

我的layout xml (R.layout。标题视图在上面的代码)看起来像这样:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@android:color/transparent" >

<com.your.package.CustomTextView
        android:id="@+id/title"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerVertical="true"
            android:layout_marginLeft="10dp"
            android:textSize="20dp"
            android:maxLines="1"
            android:ellipsize="end"
            android:text="" />
</RelativeLayout>

试试这个

public void findAndSetFont(){
        getActionBar().setTitle("SOME TEST TEXT");
        scanForTextViewWithText(this,"SOME TEST TEXT",new SearchTextViewInterface(){

            @Override
            public void found(TextView title) {

            } 
        });
    }

public static void scanForTextViewWithText(Activity activity,String searchText, SearchTextViewInterface searchTextViewInterface){
    if(activity == null|| searchText == null || searchTextViewInterface == null)
        return;
    View view = activity.findViewById(android.R.id.content).getRootView();
    searchForTextViewWithTitle(view, searchText, searchTextViewInterface);
}

private static void searchForTextViewWithTitle(View view, String searchText, SearchTextViewInterface searchTextViewInterface)
{
    if (view instanceof ViewGroup)
    {
        ViewGroup g = (ViewGroup) view;
        int count = g.getChildCount();
        for (int i = 0; i < count; i++)
            searchForTextViewWithTitle(g.getChildAt(i), searchText, searchTextViewInterface);
    }
    else if (view instanceof TextView)
    {
        TextView textView = (TextView) view;
        if(textView.getText().toString().equals(searchText))
            if(searchTextViewInterface!=null)
                searchTextViewInterface.found(textView);
    }
}
public interface SearchTextViewInterface {
    void found(TextView title);
}