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以前只是简单的重写个BaseAdapter,将getView方法保持抽象。而ViewHolder没有抽象过。。。
ViewHolder (用了一个集合+泛型管理存取view)
/** * author : stone * email : aa86799@163.com * time : 15/7/24 14 27 */ public class StoneViewHolder { private int mPosition; private View mConvertView; private SparseArray<View> mViews; //管理listView-item中的view public StoneViewHolder(Context context, int layoutId, int position, ViewGroup parent) { this.mPosition = position; this.mConvertView = LayoutInflater.from(context).inflate(layoutId, parent, false); this.mConvertView.setTag(this); this.mViews = new SparseArray<View>(); } public View getConvertView() { return mConvertView; } public static StoneViewHolder getInstance(Context context, int layoutId, int position, View convertView, ViewGroup parent) { if (convertView == null) { return new StoneViewHolder(context, layoutId, position, parent); } else { StoneViewHolder holder = (StoneViewHolder) convertView.getTag(); holder.mPosition = position; //更新复用的convertView中 position return holder; } } public <T extends View> T getView(int viewId) { View view = mViews.get(viewId); if (view == null) { view = mConvertView.findViewById(viewId); mViews.put(viewId, view); } return (T) view; } public <T> void setTag(int viewId, T tag) { getView(viewId).setTag(tag); } public <T> T getTag(int viewId) { return (T) getView(viewId).getTag(); } /*------------------------ 设置view属性(以后扩展) --------------------------------*/ public StoneViewHolder setText(int viewId, String text) { ((TextView)getView(viewId)).setText(text); return this; } public StoneViewHolder setText(int viewId, int resId) {//R.string. ((TextView)getView(viewId)).setText(resId); return this; } public StoneViewHolder setImageBitmap(int viewId, Bitmap bitmap) { ((ImageView)getView(viewId)).setImageBitmap(bitmap); return this; } public StoneViewHolder setImageResource(int viewId, int resId) { ((ImageView)getView(viewId)).setImageResource(resId); return this; } }
/** * author : stone * email : aa86799@163.com * time : 15/7/24 14 46 */ public abstract class StoneListAdapter<T> extends BaseAdapter { private List<T> mData; private Context mContext; private int mLayoutID; public StoneListAdapter(Context context, int layoutID, List<T> data) { this.mContext = context; this.mLayoutID = layoutID; this.mData = data == null ? new ArrayList<T>() : data; } @Override public int getCount() { return mData.size(); } @Override public T getItem(int position) { return mData.get(position); } @Override public long getItemId(int position) { return position; } @Override public View getView(int position, View convertView, ViewGroup parent) { StoneViewHolder holder = StoneViewHolder.getInstance(mContext, mLayoutID, position, convertView, parent); getView(mContext, holder, position); return holder.getConvertView(); } protected abstract void getView(Context context, StoneViewHolder holder, int position); }
stoneBaseAdapter = new StoneListAdapter<User>(ListViewActivity.this, R.layout.activity_listview_item, mData) { @Override protected void getView(Context context, final StoneViewHolder holder, final int position) { User user = getItem(position); holder.setText(R.id.tv_id, user.getId()).setText(R.id.tv_name, user.getName()) .setText(R.id.tv_age, user.getAge() + ""); holder.getView(R.id.btn_test).setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { } }); } };
如果 listView.setOnItemClickListener(listener); 且item中的 button.setOnClickListener(listener);
不管怎么点击,button会一直被触发...
只需要在item的root-layout中 添加 一个属性: android:descendantFocusability="blocksDescendants"
关于item-view复用后,显示混乱:
有时条目过多,滑动到下一屏数据时,有些view复用后,view的状态(比如CheckBox的选种状态,ImageView的图片重复出现)会变乱。
一般处理呢,需要有一个机制,来管理一种对应关系: 当前position对应哪种状态
比如说checkBox选中状态混乱:
class MyAdapter extends StoneListAdapter<User> { private SparseBooleanArray mCheckStateArray; public MyAdapter(Context context, int layoutID, List data) { super(context, layoutID, data); this.mCheckStateArray = new SparseBooleanArray(); } public void setChecked(int position, boolean isChecked) { mCheckStateArray.put(position, isChecked); } public boolean isChecked(int position) { return mCheckStateArray.get(position); } @Override protected void getView(Context context, final StoneViewHolder holder, final int position) { CheckBox cb = holder.getView(R.id.cb_check); cb.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() { @Override public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) { setChecked(position, isChecked);//记录状态,防缓存显示 } }); cb.setChecked(isChecked(position)); } }
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Android BaseAdapter和ViewHolder 优化
原文地址:http://blog.csdn.net/jjwwmlp456/article/details/47043585