Added method XmlElement::getChildByAttribute().

modules/juce_core/xml/juce_XmlElement.cpp

@@ -562,6 +562,8 @@ XmlElement* XmlElement::getChildElement (const int index) const noexcept
 
 XmlElement* XmlElement::getChildByName (StringRef childName) const noexcept
 {
+    jassert (! childName.isEmpty());
+
     for (XmlElement* child = firstChildElement; child != nullptr; child = child->nextListItem)
         if (child->hasTagName (childName))
             return child;
@@ -569,6 +571,17 @@ XmlElement* XmlElement::getChildByName (StringRef childName) const noexcept
     return nullptr;
 }
 
+XmlElement* XmlElement::getChildByAttribute (StringRef attributeName, StringRef attributeValue) const noexcept
+{
+    jassert (! attributeName.isEmpty());
+
+    for (XmlElement* child = firstChildElement; child != nullptr; child = child->nextListItem)
+        if (child->compareAttribute (attributeName, attributeValue))
+            return child;
+
+    return nullptr;
+}
+
 void XmlElement::addChildElement (XmlElement* const newNode) noexcept
 {
     if (newNode != nullptr)

modules/juce_core/xml/juce_XmlElement.h

@@ -483,10 +483,20 @@ public:
 
         @param tagNameToLookFor     the tag name of the element you want to find
         @returns the first element with this tag name, or nullptr if none is found
-        @see getNextElement, isTextElement, getChildElement
+        @see getNextElement, isTextElement, getChildElement, getChildByAttribute
     */
     XmlElement* getChildByName (StringRef tagNameToLookFor) const noexcept;
 
+    /** Returns the first sub-element which has an attribute that matches the given value.
+
+        @param attributeName     the name of the attribute to check
+        @param attributeValue    the target value of the attribute
+        @returns the first element with this attribute value, or nullptr if none is found
+        @see getChildByName
+    */
+    XmlElement* getChildByAttribute (StringRef attributeName,
+                                     StringRef attributeValue) const noexcept;
+
     //==============================================================================
     /** Appends an element to this element's list of children.