如何将gridView替换为RecyclerView [英] How to replace gridView to RecyclerView
本文介绍了如何将gridView替换为RecyclerView的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我正在开发一个应用程序，其中我以前的同事使用GridView来显示数据，但是我想将recyclerview和cardadapter一起使用，但是我没有得到如何做的信息.
I am developing an app in which my previous colleague used GridView to show data,but i want to use recyclerview with cardadapter, but I am not getting how to do that.
这是我的mainActivity代码:
Here is my code for mainActivity:
public class ActivityCategoryList extends Activity {
GridView listCategory;
ProgressBar prgLoading;
TextView txtAlert;
// declare adapter object to create custom category list
AdapterCategoryList cla;
// create arraylist variables to store data from server
static ArrayList<Long> Category_ID = new ArrayList<Long>();
static ArrayList<String> Category_name = new ArrayList<String>();
static ArrayList<String> Category_image = new ArrayList<String>();
String CategoryAPI;
int IOConnect = 0;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.category_list);
ActionBar bar = getActionBar();
bar.setBackgroundDrawable(new ColorDrawable(getResources().getColor(R.color.header)));
bar.setDisplayHomeAsUpEnabled(true);
bar.setHomeButtonEnabled(true);
bar.setTitle("Category");
prgLoading = (ProgressBar) findViewById(R.id.prgLoading);
listCategory = (GridView) findViewById(R.id.listCategory);
txtAlert = (TextView) findViewById(R.id.txtAlert);
cla = new AdapterCategoryList(ActivityCategoryList.this);
// category API url
CategoryAPI = Constant.CategoryAPI+"?accesskey="+Constant.AccessKey;
// call asynctask class to request data from server
new getDataTask().execute();
// event listener to handle list when clicked
listCategory.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> arg0, View arg1, int position,
long arg3) {
// TODO Auto-generated method stub
// go to menu page
Intent iMenuList = new Intent(ActivityCategoryList.this, ActivityMenuList.class);
iMenuList.putExtra("category_id", Category_ID.get(position));
iMenuList.putExtra("category_name", Category_name.get(position));
startActivity(iMenuList);
overridePendingTransition(R.anim.open_next, R.anim.close_next);
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_category, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
switch (item.getItemId()) {
case R.id.cart:
// refresh action
Intent iMyOrder = new Intent(ActivityCategoryList.this, ActivityCart.class);
startActivity(iMyOrder);
overridePendingTransition (R.anim.open_next, R.anim.close_next);
return true;
case R.id.refresh:
IOConnect = 0;
listCategory.invalidateViews();
clearData();
new getDataTask().execute();
return true;
case android.R.id.home:
// app icon in action bar clicked; go home
this.finish();
overridePendingTransition(R.anim.open_main, R.anim.close_next);
return true;
default:
return super.onOptionsItemSelected(item);
}
}
// clear arraylist variables before used
void clearData(){
Category_ID.clear();
Category_name.clear();
Category_image.clear();
}
// asynctask class to handle parsing json in background
public class getDataTask extends AsyncTask<Void, Void, Void>{
// show progressbar first
getDataTask(){
if(!prgLoading.isShown()){
prgLoading.setVisibility(0);
txtAlert.setVisibility(8);
}
}
@Override
protected Void doInBackground(Void... arg0) {
// TODO Auto-generated method stub
// parse json data from server in background
parseJSONData();
return null;
}
@Override
protected void onPostExecute(Void result) {
// TODO Auto-generated method stub
// when finish parsing, hide progressbar
prgLoading.setVisibility(8);
// if internet connection and data available show data on list
// otherwise, show alert text
if((Category_ID.size() > 0) && (IOConnect == 0)){
listCategory.setVisibility(0);
listCategory.setAdapter(cla);
}else{
txtAlert.setVisibility(0);
}
}
}
// method to parse json data from server
public void parseJSONData(){
clearData();
try {
// request data from Category API
HttpClient client = new DefaultHttpClient();
HttpConnectionParams.setConnectionTimeout(client.getParams(), 15000);
HttpConnectionParams.setSoTimeout(client.getParams(), 15000);
HttpUriRequest request = new HttpGet(CategoryAPI);
HttpResponse response = client.execute(request);
InputStream atomInputStream = response.getEntity().getContent();
BufferedReader in = new BufferedReader(new InputStreamReader(atomInputStream));
String line;
String str = "";
while ((line = in.readLine()) != null){
str += line;
}
// parse json data and store into arraylist variables
JSONObject json = new JSONObject(str);
JSONArray data = json.getJSONArray("data");
for (int i = 0; i < data.length(); i++) {
JSONObject object = data.getJSONObject(i);
JSONObject category = object.getJSONObject("Category");
Category_ID.add(Long.parseLong(category.getString("Category_ID")));
Category_name.add(category.getString("Category_name"));
Category_image.add(category.getString("Category_image"));
Log.d("Category name", Category_name.get(i));
}
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
IOConnect = 1;
e.printStackTrace();
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
@Override
protected void onDestroy() {
// TODO Auto-generated method stub
//cla.imageLoader.clearCache();
listCategory.setAdapter(null);
super.onDestroy();
}
@Override
public void onConfigurationChanged(final Configuration newConfig)
{
// Ignore orientation change to keep activity from restarting
super.onConfigurationChanged(newConfig);
}
@Override
public void onBackPressed() {
// TODO Auto-generated method stub
super.onBackPressed();
finish();
overridePendingTransition(R.anim.open_main, R.anim.close_next);
}
}
这是适配器类的代码:
Class AdapterCategoryList扩展了BaseAdapter {
class AdapterCategoryList extends BaseAdapter {
private Activity activity;
public ImageLoader imageLoader;
public AdapterCategoryList(Activity act) {
this.activity = act;
imageLoader = new ImageLoader(act);
}
public int getCount() {
// TODO Auto-generated method stub
return ActivityCategoryList.Category_ID.size();
}
public Object getItem(int position) {
// TODO Auto-generated method stub
return position;
}
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
ViewHolder holder;
if(convertView == null){
LayoutInflater inflater = (LayoutInflater) activity
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = inflater.inflate(R.layout.category_list_item, null);
holder = new ViewHolder();
convertView.setTag(holder);
}else{
holder = (ViewHolder) convertView.getTag();
}
holder.txtText = (TextView) convertView.findViewById(R.id.txtText);
holder.imgThumb = (ImageView) convertView.findViewById(R.id.imgThumb);
holder.txtText.setText(ActivityCategoryList.Category_name.get(position));
imageLoader.DisplayImage(Constant.AdminPageURL+ActivityCategoryList.Category_image.get(position), holder.imgThumb);
return convertView;
}
static class ViewHolder {
TextView txtText;
ImageView imgThumb;
}
}
我对此并不陌生，我认为对于recyclerview，我们还需要创建一个列表类.
I am new to this, and I think for recyclerview we need to create a list class also.
如果有人对此有任何想法，您能帮我吗?
If anyone have any idea about this, can you help me?
推荐答案
我没有检查您的整个代码，但是归档此代码的关键步骤是:
I didn't check your whole code, but the key steps to archieve this is:
设置适配器
recyclerView.setAdapter(adpter);
和创建并设置LayoutManager
and create and set an LayoutManager
int columns=3;
reyclerView.setLayoutManager(new GridLayoutManager(context,columns););
请参见 RecyclerView文档和 查看全文
