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POAdd subclasses of templated base-class to container without super-base-class?
 

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    <p>I'm trying to create a vector (or any STL container, really) that could hold a set of various objects that are subclasses of one specific type. The problem is that my base class is templated.</p> <p>From what I can tell, I have to create an interface/abstract super base class (not sure what the preferred C++ terminology is). I'd prefer not to do this, and just use my (templated) abstract base class. Below is some example code.</p> <p>Basically, is there a way not to require the <code>WidgetInterface</code>? Someway to tell the compiler to ignore template requirements? If I must have <code>WidgetInterface</code>, am I going the right way with the following?</p> <pre><code>#include &lt;vector&gt; #include "stdio.h" enum SomeEnum{ LOW = 0, HIGH = 112358 }; // Would like to remove this WidgetInterface class WidgetInterface{ public: // have to define this so we can call it while iterating // (would remove from Widget if ended up using this SuperWidget // non-template baseclass method) virtual void method() = 0; }; template &lt;class TDataType&gt; class AbstractWidget : public WidgetInterface{ public: TDataType mData; virtual void method() = 0; // ... bunch of helper methods etc }; class EnumWidget : public AbstractWidget&lt;SomeEnum&gt;{ public: EnumWidget(){ mData = HIGH; } void method(){ printf("%d\n", mData); // sprintf for simplicity } }; class IntWidget : public AbstractWidget&lt;int&gt;{ public: IntWidget(){ mData = -1; } void method(){ printf("%d\n", mData); // sprintf for simplicity } }; int main(){ // this compiles but isn't a workable solution, not generic enough std::vector&lt; AbstractWidget&lt;int&gt;* &gt; widgets1; // only way to do store abitary subclasses? std::vector&lt;WidgetInterface*&gt; widgets2; widgets2.push_back(new EnumWidget()); widgets2.push_back(new IntWidget()); for(std::vector&lt;WidgetInterface*&gt;::iterator iter = widgets2.begin(); iter != widgets2.end(); iter++){ (*iter)-&gt;method(); } // This is what i'd _like_ to do, without needing WidgetInterface // std::vector&lt; AbstractWidget* &gt; widgets3; return 0; } </code></pre>
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