actionbar spinner-用法实例

今天需要更改一个actionbar上的spinner的字体颜色，结果试了好长时间都没有解决，最后才发现，原来他是在代码下增加的一个textview，然后使用adapter加载的，并不是直接用framework下的布局。现在总结下spinner的使用方法，直接见下面的代码

1）首先要有一个spinneradapter来跟spinner进行数据加载

 private BaseAdapter mStackAdapter = new BaseAdapter() {
        @Override
        public int getCount() {
            return mState.stack.size();
        }

        @Override
        public DocumentInfo getItem(int position) {
            return mState.stack.get(mState.stack.size() - position - 1);
        }

        @Override
        public long getItemId(int position) {
            return position;
        }

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            if (convertView == null) {
                convertView = LayoutInflater.from(parent.getContext())
                        .inflate(R.layout.item_title, parent, false);
            }

            final TextView title = (TextView) convertView.findViewById(android.R.id.title);
            final DocumentInfo doc = getItem(position);

            if (position == 0) {
                final RootInfo root = getCurrentRoot();
                title.setText(root.title);
            } else {
                title.setText(doc.displayName);
            }    

            // No padding when shown in actionbar
            convertView.setPadding(0, 0, 0, 0);
            return convertView;
        }
@Override
        public View getDropDownView(int position, View convertView, ViewGroup parent) {
            if (convertView == null) {
                convertView = LayoutInflater.from(parent.getContext())
                        .inflate(R.layout.item_title, parent, false);
            }

            final ImageView subdir = (ImageView) convertView.findViewById(R.id.subdir);
            final TextView title = (TextView) convertView.findViewById(android.R.id.title);
            final DocumentInfo doc = getItem(position);

            if (position == 0) {
                final RootInfo root = getCurrentRoot();
                title.setText(root.title);
                subdir.setVisibility(View.GONE);
            } else {
                title.setText(doc.displayName);
                subdir.setVisibility(View.VISIBLE);
            }

            return convertView;
        }
    };

上面有两个比较重要的方法

一个是getview：这个方法是加载提示prompt用的

一个是getDropView：这个是加载下拉框用的

2）添加dropview点击监听事件

    private OnNavigationListener mStackListener = new OnNavigationListener() {
        @Override
        public boolean onNavigationItemSelected(int itemPosition, long itemId) {
            if (mIgnoreNextNavigation) {
                mIgnoreNextNavigation = false;
                return false;
            }    

            while (mState.stack.size() > itemPosition + 1) {
                mState.stackTouched = true;
                mState.stack.pop();
            }
            onCurrentDirectoryChanged(ANIM_UP);
            return true;
        }
    }; 

3）添加spinneradapter跟dropview

actionBar.setListNavigationCallbacks(mStackAdapter, mStackListener);
actionBar.setSelectedNavigationItem(mStackAdapter.getCount() - 1);