Question

I always thought CharSequence[] and String[] were essential the same, however :

I have some code that has the following :

CharSequence[] mEntries;
...
String[] mEntriesString = (String[]) mEntries;
ListAdapter adapter = new ArrayAdapter<String>(getContext(), R.layout.two_lines_list_preference_row, mEntriesString)

When the code runs I get

java.lang.ClassCastException: java.lang.CharSequence[] cannot be cast to java.lang.String[]

So two questions ?

• why can this cast not happen
• why does the ArrayAdapter not allow for a CharSequence[] in it’s constructor.

Answer 1

CharSequence is interface which String, StringBuffer, StringBuilder classes implements. So CharSequence can hold any of this implementation class’s Object And CharSequence#toString returns String, try –

String[] mEntriesString = new String[mEntries.length];
int i=0;
for(CharSequence ch: mEntries){
    mEntriesString[i++] = ch.toString(); 
}