如何使用特定主題的特定樣式？

Question

我想圍繞着樣式和主題。目前，我有我的應用程序一個主題：

<style name="WhiteTheme" parent="Theme.AppCompat.Light.NoActionBar"> 
    ... 
</style> 

我也有不同的看法很多款式，像這樣：

<style name="BodyText" parent="TextAppearance.AppCompat.Body1"> 
    <item name="android:textSize">14sp</item> 
    <item name="android:textColor">@color/default_text_color</item> 
</style> 

...我用這樣的：

<TextView 
    ... 
    android:textAppearance="@style/BodyText"/> 

現在，如果我要創建一個新主題，例如DarkTheme，我如何確保將所有引用BodyText作爲其TextAppearance的TextView指向新樣式？

Answer 1

創建你想擁有整個主題不同的資源生成的attr。

<attr name="someTextColor" format="color"/> 

在你的主題

現在，定義ATTRS

<style name="WhiteTheme" parent="Theme.AppCompat.Light.NoActionBar"> 
    <item name="someTextColor">@android:color/black</item> 
</style> 

<style name="DarkTheme" parent="Theme.AppCompat"> 
    <item name="someTextColor">@android:color/white</item> 
</style> 

現在你可以使用它們。

<style name="BodyText" parent="TextAppearance.AppCompat.Body1"> 
    <item name="android:textSize">14sp</item> 
    <item name="android:textColor">?attr/someTextColor</item> 
</style> 

您也可以從代碼

得到ATTR

/** 
* Returns color for attr from the {@link Theme} 
* 
* @param theme {@link Theme} to get int from 
* @param attr Attribute of the int 
* @return dimension for attr from the {@link Theme} 
*/ 
@ColorInt 
public static int getColor(@NonNull final Theme theme, @AttrRes final int attr) { 
    final TypedArray array = theme.obtainStyledAttributes(new int[]{attr}); 
    try { 
     return array.getColor(0, Color.TRANSPARENT); 
    } finally { 
     array.recycle(); 
    } 
} 

或者作爲ColorStateList

/** 
* Returns {@link ColorStateList} for attr from the {@link Theme} 
* 
* @param theme {@link Theme} to get int from 
* @param attr Attribute of the int 
* @return dimension for attr from the {@link Theme} 
*/ 
@Nullable 
public static ColorStateList getColorStateList(@NonNull final Theme theme, 
     @AttrRes final int attr) { 
    final TypedArray array = theme.obtainStyledAttributes(new int[]{attr}); 
    try { 
     return array.getColorStateList(0); 
    } finally { 
     array.recycle(); 
    } 
} 

然後

final int someTextColor = getColor(getTheme(), R.attr.someTextColor); 
// or 
final ColorStateList someTextColor = getColorStateList(getTheme(), R.attr.someTextColor); 

Answer 2

的主題爲TextView的

<style name="Theme1" parent="Theme.AppCompat.Light.DarkActionBar" > 
     <item name="android:textColor">@color/colorAccent</item> 
     <item name="android:shadowDy">1</item> 
     <item name="android:shadowRadius">0.7</item> 
     <item name="android:textAppearance">@style/MyRedTextAppearance</item> 
    </style> 

    <style name="MyRedTextAppearance" > 
     <item name="android:textColor">@color/colorAccent</item> 
     <item name="android:shadowDy">1</item> 
     <item name="android:shadowRadius">0.7</item> 
    </style> 


    <style name="Theme2" parent="Theme.AppCompat.Light.Dialog" > 
     <item name="android:textColor">@color/colorPrimaryDark</item> 
     <item name="android:shadowDy">1</item> 
     <item name="android:shadowRadius">0.7</item> 
     <item name="android:textAppearance">@style/MyBlueTextAppearance</item> 
    </style> 

    <style name="MyBlueTextAppearance" > 
     <item name="android:textColor">@color/colorPrimary</item> 
     <item name="android:shadowDy">1</item> 
     <item name="android:shadowRadius">0.7</item> 
    </style> 

Textviews將使用

<TextView 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content" 
     style="@style/Theme1" 
     android:text="Dummy"/> 

    <TextView 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content" 
     android:text="Dummy" 
     style="@style/Theme2"/>