Android:如何在styles.xml中自定义声明XML命名空间?

时间:2015-03-30 19:18:05

标签: android xml android-layout layout android-styles

我正在尝试将自定义XML命名空间放在styles.xml中并在布局中继承它。我不知道如何在styles.xml中声明自定义XML命名空间,就像在布局xml中那样(例如xmlns:app="http://schemas.android.com/tools")。

如何在styles.xml

中使用自定义XML命名空间

我拥有的是什么:

  1. 字体资源ReallyCoolFont.ttf保存在asset/fonts

  2. my_layout.xml

    <TextView
        <!-- more attributes here -->
        app:customFont="fonts/ReallyCoolFont.ttf" 
        <!-- more attributes here -->
    </TextView>
    
  3. styles.xml

    <style name="CoolTextView">
        <!-- more items here -->
        <!-- more items here -->
    </style>
    
  4. 我想拥有什么:

    1. my_layout.xml

      <TextView
          <!-- more attributes here -->
          style="@style/CoolTextView
          <!-- more attributes here -->
      </TextView>
      
    2. styles.xml

      <style name="CoolTextView">
          <!-- more items here -->
          <item name="app:customFont">ReallyCoolFont.ttf</item>
          <!-- more items here -->
      </style>
      
    3. 我得到的错误:

      Error:(1403, 21) No resource found that matches the given name: attr     'app:customFont'.
      

8 个答案:

答案 0 :(得分:16)

1)您需要在res文件夹中的attr.xml文件中定义字体属性:

<attr name="myfonts" format="string"></attr>

2)你需要为TextView定义自定义样式,在这里我们使用我们定义的属性(myfonts):

<declare-styleable name="MyCustomStyle">
    <attr name="myfonts" />
</declare-styleable>

3)

<style name="CoolTextView">
    <item name="myfonts">ReallyCoolFont.ttf</item>
</style>

到目前为止的摘要:

<?xml version="1.0" encoding="utf-8"?>
<resources>

    <attr name="myfonts" format="string">
    </attr>

    <declare-styleable name="MyCustomStyle">
        <attr name="myfonts" />
    </declare-styleable> 

    <style name="CoolTextView">
        <item name="myfonts">ReallyCoolFont.ttf</item>
    </style>

</resources> 

4)现在您的布局将是:

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

    <com.example.MyCustomTextView
        android:id="@+id/result"
        style="@style/CoolTextView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:text="HELLO WORLD!"
        android:textSize="24dp"
        android:gravity="center" >
    </com.example.MyCustomTextView>

</RelativeLayout>

5)你的MyCustomTextView是:

public class MyCustomTextView extends TextView {


    private static final String TAG = "TextView";

    public MyCustomTextView(Context context) {
        super(context);
    }

    public MyCustomTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
        settingFont(context, attrs);
    }

    public MyCustomTextView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        settingFont(context, attrs);
    }


    private void settingFont(Context ctx, AttributeSet attrs) {
        TypedArray a = ctx.obtainStyledAttributes(attrs, R.styleable.MyCustomStyle);
        String customFont = a.getString(R.styleable.MyCustomStyle_myfonts);
        Typeface tf = null;
        try {
        tf = Typeface.createFromAsset(ctx.getAssets(), customFont);  
        } catch (Exception e) {
            Log.e(TAG,e.getMessage());
            a.recycle();
            return;
        }

        setTypeface(tf);  
        a.recycle();
    }


}

我假设您将资产中的字体放在 asset / fonts 目录中。

我强烈建议您阅读this

答案 1 :(得分:9)

您无需添加任何前缀即可在样式资源文件中引用自定义属性。这样做会很好用:

<style name="CoolTextView">
    <item name="customFont">ReallyCoolFont.ttf</item>
</style>

答案 2 :(得分:4)

你不需要任何前缀,没有它们就能工作。这是我的一个项目的代码,它可以正常工作

<style name="defaultTriangle">
    <item name="triangleColor">#FF33B5E5</item>
    <item name="triangleStrokeColor">@android:color/black</item>
    <item name="triangleStrokeWidth">3dp</item>
</style>


<si.kseneman.views.Triangle
    style="@style/defaultTriangle"
    android:layout_width="match_parent"
    android:layout_height="0dip"
    android:layout_weight="1"
    android:padding="10dp"
    android:rotation="0"
    />

答案 3 :(得分:4)

答案是不在样式中指定名称空间。

<?xml version="1.0" encoding="utf-8" ?>
<resources xmlns:custom="http://schemas.android.com/apk/res/com.custom.project">
    <style name="CustomStyle">
        <item name="android:layout_width">wrap_content</item>
        <item name="android:layout_height">wrap_content</item>

        <item name="customAttr">value</item> <!-- tee hee -->
    </style>
</resources>

答案 4 :(得分:2)

我接下来做了自定义字体 的 CustomTextView

public class KlavikaTextView extends TextView {

  private final static int KLAVIKA_BOLD = 0;
  private final static int KLAVIKA_BOLD_ITALIC = 1;
  private final static int KLAVIKA_LIGHT = 2;
  private final static int KLAVIKA_LIGHT_ITALIC = 3;
  private final static int KLAVIKA_MEDIUM = 4;
  private final static int KLAVIKA_MEDIUM_ITALIC = 5;
  private final static int KLAVIKA_REGULAR = 6;
  private final static int KLAVIKA_REGULAR_ITALIC = 7;

public KlavikaTextView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
    parseAttributes(context, attrs);
}

public KlavikaTextView(Context context, AttributeSet attrs) {
    super(context, attrs);
    parseAttributes(context, attrs);
}

public KlavikaTextView(Context context) {
    super(context);

}

private void parseAttributes(Context context, AttributeSet attrs) {
    TypedArray values = context.obtainStyledAttributes(attrs, R.styleable.KlavikaTextView);

    // The value 0 is a default, but shouldn't ever be used since the attr is an enum
    int typeface = values.getInt(R.styleable.KlavikaTextView_typeface, KLAVIKA_REGULAR);

    // You can instantiate your typeface anywhere, I would suggest as a
    // singleton somewhere to avoid unnecessary copies
    switch (typeface) {
      case KLAVIKA_BOLD:
        setTypeface(App.klavikaBold);
        break;
      case KLAVIKA_BOLD_ITALIC:
        setTypeface(App.klavikaBoldItalic);
        break;
      case KLAVIKA_LIGHT:
        setTypeface(App.klavikaLight);
        break;
      case KLAVIKA_LIGHT_ITALIC:
        setTypeface(App.klavikaLightItalic);
        break;
      case KLAVIKA_MEDIUM:
        setTypeface(App.klavikaMedium);
        break;
      case KLAVIKA_MEDIUM_ITALIC:
        setTypeface(App.klavikaMediumItalic);
        break;
      case KLAVIKA_REGULAR_ITALIC:
        setTypeface(App.klavikaRegularItalic);
        break;
      case KLAVIKA_REGULAR:
      default:
        setTypeface(App.klavikaRegular);
        break;

    }
}}

然后在值中我创建了 attr.xml

 <!-- Define the values for the attribute -->
<attr name="typeface" format="enum">
    <enum name="klavika_bold" value="0" />
    <enum name="klavika_bold_italic" value="1" />
    <enum name="klavika_light" value="2" />
    <enum name="klavika_light_italic" value="3" />
    <enum name="klavika_medium" value="4" />
    <enum name="klavika_medium_italic" value="5" />
    <enum name="klavika_regular" value="6" />
    <enum name="klavika_regular_italic" value="7" />
</attr>

<!--
     Tell Android that the class "KlavikaTextView" can be styled,
     and which attributes it supports-->
<declare-styleable name="KlavikaTextView">
    <attr name="typeface" />
</declare-styleable>

接下来创建样式

  <style name="TextView.Example">
    <item name="typeface">klavika_bold</item>
  </style>

您可以将此样式用于xml布局

style="@style/TextView.Example" 

答案 5 :(得分:1)

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

    <style name="my_style"> <item name="custom:tag">some_value</item> </style>

</resources>

您正在尝试将XML命名空间应用于属性值,但该属性值无法正常工作。在这种情况下,您应该直接指定包名称,如下所示:

 <style name="my_style"> <item name="com.my.project:tag">some_value</item> </style>

答案 6 :(得分:1)

通过代码

快速解决方案

 String pathFont = "fonts/ReallyCoolFont.ttf";
 TextView text = (TextView) findViewById(R.id.TextView1);
 Typeface fontFace = Typeface.createFromAsset( getAssets(), pathFont );
 text.setTypeface( fontFace );

第三方库,用XML解决问题!

1 - https://github.com/leok7v/android-textview-custom-fonts

2 - https://github.com/ragunathjawahar/android-typeface-textview

我的建议

您将有其他需求,并为每个组件 你必须自定义一个类。

您有其他布局和N TextView 组件的另一个问题 为了维护 ,你将会有很多工作。

我在我的活动的OnCreate中的项目中使用此方法 如果我需要更改字体,我必须这样做 仅在每个活动的OnCreate方法中。

 private static final String FONT = "ReallyCoolFont.ttf";

public static void allTextView(final Context context, final View root) {
      String fontPath = FONT;
    try {
        if (root instanceof ViewGroup) {
            ViewGroup viewGroup = (ViewGroup) root;
            int childCount = viewGroup.getChildCount();
            for (int i = 0; i < childCount; i++)
                allTextView(context, viewGroup.getChildAt(i) );
        } else if (root instanceof TextView)
            ((TextView) root).setTypeface(Typeface.createFromAsset(context.getAssets(), fontPath));
    } catch (Exception e) { 
        e.printStackTrace();
    }
}

// call in OnCreate Activity    
allTextView(this, findViewById(R.layout.main) );

答案 7 :(得分:0)

使用<declare-styleable>标记定义自定义属性;通常该文件名为attrs.xml。命名空间声明中将包含您应用的包名称。

此处描述了整个过程:Creating a View Class | Android Developers