java.lang.IllegalStateException: Cannot add header view to list -- setAdapter has already been called.

分析：android 4.2.X及以下的版本，addHeaderView必须在setAdapter之前，否则会抛出IllegalStateException。

android 4.2.X（API 17） ListView源码如下：

public void addHeaderView(View v, Object data, boolean isSelectable) {

if (mAdapter != null && ! (mAdapter instanceof HeaderViewListAdapter)) {
throw new IllegalStateException(
"Cannot add header view to list -- setAdapter has already been called.");
}

FixedViewInfo info = new FixedViewInfo();
info.view = v;
info.data = data;
info.isSelectable = isSelectable;
mHeaderViewInfos.add(info);

// in the case of re-adding a header view, or adding one later on,
// we need to notify the observer
if (mAdapter != null && mDataSetObserver != null) {
mDataSetObserver.onChanged();
}
}

　　

android 4.3.X（API 18）ListView源码如下：

public void addHeaderView(View v, Object data, boolean isSelectable) {
......

// Wrap the adapter if it wasn't already wrapped.
if (mAdapter != null) {
if (!(mAdapter instanceof HeaderViewListAdapter)) {
mAdapter = new HeaderViewListAdapter(mHeaderViewInfos, mFooterViewInfos, mAdapter);
}

// In the case of re-adding a header view, or adding one later on,
// we need to notify the observer.
if (mDataSetObserver != null) {
mDataSetObserver.onChanged();
}
}
}

所以为了兼容android4.2.x及以下的版本，最好先addHeaderView,后setAdapter.