优化

app/src/main/java/io/legado/app/ui/config/OtherConfigFragment.kt

@@ -74,6 +74,9 @@ class OtherConfigFragment : PreferenceFragmentCompat(),
                 }
                 toast(R.string.clear_cache_success)
             }
+            "defaultCover" -> {
+                
+            }
         }
         return super.onPreferenceTreeClick(preference)
     }

app/src/main/res/values-zh-rHK/strings.xml

@@ -719,4 +719,6 @@
     <string name="alipay_payment_qr_code">支付寶收款二維碼</string>
     <string name="qq_collection_qr_code">QQ收款二維碼</string>
     <string name="contributors_summary">gedoor,Invinciblelee等,详情请在github中查看</string>
+    <string name="clear_cache_summary">清除已下载书籍和字体缓存</string>
+    <string name="default_cover">默认封面</string>
 </resources>

app/src/main/res/values-zh-rTW/strings.xml

@@ -719,5 +719,7 @@
     <string name="alipay_payment_qr_code">支付寶收款二維碼</string>
     <string name="qq_collection_qr_code">QQ收款二維碼</string>
     <string name="contributors_summary">gedoor,Invinciblelee等,详情请在github中查看</string>
+    <string name="clear_cache_summary">清除已下载书籍和字体缓存</string>
+    <string name="default_cover">默认封面</string>
 
 </resources>

app/src/main/res/values-zh/strings.xml

@@ -719,4 +719,6 @@
     <string name="alipay_payment_qr_code">支付宝收款二维码</string>
     <string name="qq_collection_qr_code">QQ收款二维码</string>
     <string name="contributors_summary">gedoor,Invinciblelee等,详情请在github中查看</string>
+    <string name="clear_cache_summary">清除已下载书籍和字体缓存</string>
+    <string name="default_cover">默认封面</string>
 </resources>

app/src/main/res/values/strings.xml

@@ -720,5 +720,7 @@
     <string name="alipay_payment_qr_code">支付宝收款二维码</string>
     <string name="qq_collection_qr_code">QQ收款二维码</string>
     <string name="contributors_summary">gedoor,Invinciblelee等,详情请在github中查看</string>
+    <string name="clear_cache_summary">清除已下载书籍和字体缓存</string>
+    <string name="default_cover">默认封面</string>
 
 </resources>

app/src/main/res/xml/pref_config_other.xml

@@ -31,6 +31,11 @@
             app:allowDividerBelow="false"
             app:iconSpaceReserved="false" />
 
+        <io.legado.app.ui.widget.prefs.Preference
+            android:key="defaultCover"
+            android:title="@string/default_cover"
+            app:iconSpaceReserved="false" />
+
     </io.legado.app.ui.widget.prefs.PreferenceCategory>
 
     <io.legado.app.ui.widget.prefs.PreferenceCategory
@@ -60,6 +65,7 @@
         <io.legado.app.ui.widget.prefs.Preference
             android:key="cleanCache"
             android:title="@string/cleanCache"
+            android:summary="@string/clear_cache_summary"
             app:iconSpaceReserved="false" />
 
         <io.legado.app.ui.widget.prefs.SwitchPreference