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POinsert method for an array of objects c++
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copied!<p>I have an array of integer data called values and I need to insert a new Integerdata into the array. I have thought about making a temp array to copy all the contents and then make a new array with a size + 1 the original but I keep getting many errors. any help? </p> <pre><code>class IntegerData : public Data { public: int value; // This is the syntax for a constructor that initializes the // properties value to the parameters IntegerData(int value) : value(value) {} } class ArrayCollection : Collection { // length of values is always the same as count Data ** values; int count; public: ArrayCollection() { // initialize the array to NULL this->values = NULL; this->count = 0; } ~ArrayCollection() { // must clean up the internally allocated array here if (values != NULL) { delete [] values; } } /** * Returns the count of the number of elements in the Collection */ int size() const { return count; } /** * Gets the Data value at the specified index. If index >= size() then * NULL is returned. */ Data * get(int index) { if (index >= size()) { return NULL; } else { return values[index]; } } ????-- I need help with this method-- // I try to dynamically allocate tempArray but I get the error message saying: cannot // allocate an object of abstract type 'Data' void insert(Data * other){ count++; Data **tempArray = new Data[count]; for(int i = 0; i < count; i++){ tempArray[i] = values[i]; } delete [] values; values = tempArray; } } int main(int argc, const char * argv[]) { // create an ArrayCollection for our collection of integers ArrayCollection * collection = new ArrayCollection(); if (argc == 1) { // they didn't provide any arguments to the program, insert a // value of zero so that the main function still works collection->insert(new IntegerData(0)); } else { for (int i = 1; i < argc; i++) { // read user input for integer value int x = atoi(argv[i]); // insert it to our collection collection->insert(new IntegerData(x)); } } // print the collection cout << collection->toString() << endl; // check the implementation of member IntegerData * five = new IntegerData(5); cout << "five is a member of collection? " << collection->member(five) << endl; // now we are going to insert and remove a few items -- MARKER (a) IntegerData * v0 = (IntegerData *)collection->get(0); collection->remove(v0); cout << collection->toString() << endl; // check after removing the 0th element -- MARKER (b) cout << "five is a member of collection? " << collection->member(five) << endl; collection->insert(v0); cout << collection->toString() << endl; // check after inserting the 0th element back cout << "five is a member of collection? " << collection->member(five) << endl; // clean up memory delete five; // must delete IntegerData instances that we allocated in main // because they are not deleted by the data structure for (int i = 0; i < collection->size(); i++) { delete collection->get(i); } // now delete the data structure -- MARKER (c) delete collection; } </code></pre>

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