随着Android 8.0在应用程序中使用自定义字体变得容易下载字体。 我们可以直接将字体添加到项目文件夹中的res/font/文件夹中，这样一来，字体就会自动在Android Studio中可用。

现在将fontFamily属性设置为字体列表或单击更多并选择您选择的字体。这将添加tools:fontFamily="@font/your_font_file"行到你的TextView。

这将自动生成几个文件。

1. 在values文件夹中，它将创建fonts_certs.xml。

2. 在Manifest中，它会添加这样的行:

  <meta-data
            android:name="preloaded_fonts"
            android:resource="@array/preloaded_fonts" /> 

3. preloaded_fonts.xml

<resources>
    <array name="preloaded_fonts" translatable="false">
        <item>@font/open_sans_regular</item>
        <item>@font/open_sans_semibold</item>
    </array>
</resources>

如果你把字体放在正确的地方，字体文件本身没有错误，你的代码应该像那样工作，RATTLESNAKE。

然而，如果你能在你的布局xml中定义一种字体，就会容易得多，就像这样:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity" >

    <!-- This text view is styled with the app theme -->
    <com.innovattic.font.FontTextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="This uses my font in bold italic style" />

    <!-- This text view is styled here and overrides the app theme -->
    <com.innovattic.font.FontTextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        app:flFont="anotherFont"
        android:textStyle="normal"
        android:text="This uses another font in normal style" />

    <!-- This text view is styled with a style and overrides the app theme -->
    <com.innovattic.font.FontTextView
        style="@style/StylishFont"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="This also uses another font in normal style" />

</LinearLayout>

随附res/values/styles.xml:

<?xml version="1.0" encoding="utf-8"?>
<resources xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools">

    <!-- Application theme -->
    <!-- Use a different parent if you don't want Holo Light -->
    <style name="AppTheme" parent="android:Theme.Holo.Light.DarkActionBar">
        <item name="android:textViewStyle">@style/MyTextViewStyle</item>
    </style>

    <!-- Style to use for ALL text views (including FontTextView) -->
    <!-- Use a different parent if you don't want Holo Light -->
    <style name="MyTextViewStyle" parent="@android:style/Widget.Holo.Light.TextView">
        <item name="android:textAppearance">@style/MyTextAppearance</item>
    </style>

    <!-- Text appearance to use for ALL text views (including FontTextView) -->
    <!-- Use a different parent if you don't want Holo Light -->
    <style name="MyTextAppearance" parent="@android:style/TextAppearance.Holo">
        <!-- Alternatively, reference this font with the name "aspergit" -->
        <!-- Note that only our own TextView's will use the font attribute -->
        <item name="flFont">someFont</item>
        <item name="android:textStyle">bold|italic</item>
    </style>

    <!-- Alternative style, maybe for some other widget -->
    <style name="StylishFont">
        <item name="flFont">anotherFont</item>
        <item name="android:textStyle">normal</item>
    </style>

</resources>

为此，我专门创建了几个工具。参考GitHub上的这个项目，或者看看这篇解释了整个事情的博客文章。

由于我对SO的所有解决方案都不满意，所以我提出了我的解决方案。这是基于标签的一个小技巧(即你不能在你的代码中使用标签)，我把字体路径放在那里。所以当定义视图时，你可以这样做:

<TextView
        android:id="@+id/textViewHello1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World 1"
        android:tag="fonts/Oswald-Regular.ttf"/>

或:

<TextView
        android:id="@+id/textViewHello2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Hello World 2"
        style="@style/OswaldTextAppearance"/>

<style name="OswaldTextAppearance">
        <item name="android:tag">fonts/Oswald-Regular.ttf</item>
        <item name="android:textColor">#000000</item>
</style>

现在你可以显式地访问/设置视图如下:

TextView textView = TextViewHelper.setupTextView(this, R.id.textViewHello1).setText("blah");

或者只是通过:

TextViewHelper.setupTextViews(this, (ViewGroup) findViewById(R.id.parentLayout)); // parentLayout is the root view group (relative layout in my case)

你问的魔法课是什么?主要是从另一个SO帖子中粘来的，为活动和片段提供了helper方法:

import android.app.Activity;
import android.content.Context;
import android.graphics.Typeface;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;

import java.util.HashMap;
import java.util.Map;

public class TextViewHelper {
    private static final Map<String, Typeface> mFontCache = new HashMap<>();

    private static Typeface getTypeface(Context context, String fontPath) {
        Typeface typeface;
        if (mFontCache.containsKey(fontPath)) {
            typeface = mFontCache.get(fontPath);
        } else {
            typeface = Typeface.createFromAsset(context.getAssets(), fontPath);
            mFontCache.put(fontPath, typeface);
        }
        return typeface;
    }

    public static void setupTextViews(Context context, ViewGroup parent) {
        for (int i = parent.getChildCount() - 1; i >= 0; i--) {
            final View child = parent.getChildAt(i);
            if (child instanceof ViewGroup) {
                setupTextViews(context, (ViewGroup) child);
            } else {
                if (child != null) {
                    TextViewHelper.setupTextView(context, child);
                }
            }
        }
    }

    public static void setupTextView(Context context, View view) {
        if (view instanceof TextView) {
            if (view.getTag() != null) // also inherited from TextView's style
            {
                TextView textView = (TextView) view;
                String fontPath = (String) textView.getTag();
                Typeface typeface = getTypeface(context, fontPath);
                if (typeface != null) {
                    textView.setTypeface(typeface);
                }
            }
        }
    }

    public static TextView setupTextView(View rootView, int id) {
        TextView textView = (TextView) rootView.findViewById(id);
        setupTextView(rootView.getContext().getApplicationContext(), textView);
        return textView;
    }

    public static TextView setupTextView(Activity activity, int id) {
        TextView textView = (TextView) activity.findViewById(id);
        setupTextView(activity.getApplicationContext(), textView);
        return textView;
    }
}

最简单的解决方案android支持现在!

使用自定义字体在xml:

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:fontFamily="@font/[your font resource]"/>

看详细信息:

https://developer.android.com/guide/topics/ui/look-and-feel/fonts-in-xml.html

我知道已经有了很好的答案，但这里有一个完全工作的实现。

这是自定义文本视图:

package com.mycompany.myapp.widget;

/**
 * Text view with a custom font.
 * <p/>
 * In the XML, use something like {@code customAttrs:customFont="roboto-thin"}. The list of fonts
 * that are currently supported are defined in the enum {@link CustomFont}. Remember to also add
 * {@code xmlns:customAttrs="http://schemas.android.com/apk/res-auto"} in the header.
 */
public class CustomFontTextView extends TextView {

    private static final String sScheme =
            "http://schemas.android.com/apk/res-auto";
    private static final String sAttribute = "customFont";

    static enum CustomFont {
        ROBOTO_THIN("fonts/Roboto-Thin.ttf"),
        ROBOTO_LIGHT("fonts/Roboto-Light.ttf");

        private final String fileName;

        CustomFont(String fileName) {
            this.fileName = fileName;
        }

        static CustomFont fromString(String fontName) {
            return CustomFont.valueOf(fontName.toUpperCase(Locale.US));
        }

        public Typeface asTypeface(Context context) {
            return Typeface.createFromAsset(context.getAssets(), fileName);
        }
    }

    public CustomFontTextView(Context context, AttributeSet attrs) {
        super(context, attrs);

        if (isInEditMode()) {
            return;
        } else {
            final String fontName = attrs.getAttributeValue(sScheme, sAttribute);

            if (fontName == null) {
                throw new IllegalArgumentException("You must provide \"" + sAttribute + "\" for your text view");
            } else {
                final Typeface customTypeface = CustomFont.fromString(fontName).asTypeface(context);
                setTypeface(customTypeface);
            }
        }
    }
}

这里是自定义属性。这应该进入你的res/attrs.xml文件:

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <declare-styleable name="CustomFontTextView">
        <attr name="customFont" format="string"/>
    </declare-styleable>
</resources>

下面是你如何使用它。我将使用一个相对布局来包装它并显示customAttr声明，但它显然可以是您已经拥有的任何布局。

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:customAttrs="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <com.mycompany.myapp.widget.CustomFontTextView
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:text="foobar"
         customAttrs:customFont="roboto_thin" />

</RelativeLayout>

是的，就像Dipali说的那样，下载字体非常简单。

你是这样做的……

Place a TextView. In the properties pane, select the fontFamily dropdown. If it isn't there, find the caret thingy (the > and click on it to expand textAppearance) under the. Expand the font-family drop down. In the little list, scroll all the way down till you see more fonts This will open up a dialog box where you can search from Google Fonts Search for the font you like with the search bar at the top Select your font. Select the style of the font you like (i.e. bold, normal, italic, etc) In the right pane, choose the radio button that says Add font to project Click okay. Now your TextView has the font you like!

奖金: 如果你想在你的应用程序中使用所选字体的文本样式，只需添加<item name="android:fontfamily">@font/fontnamehere</item>到你的styles.xml