我有一个活动，其中的项目来自数据库，我想要设置相同的图标。我尝试了listview，但听说了recyclerview，但我似乎无法找到解决方法，我该如何加载它。请帮助
这是我的列表视图：
public class TypeMenu extends AppCompatActivity {
private String TAG = TypeMenu.class.getSimpleName();
String bid;
private ProgressDialog pDialog;
private ListView lv;
private static final String TAG_BID = "bid";
// URL to get contacts JSON
private static String url = "http://cloud....com/brtemp/index.php";
ArrayList<HashMap<String, String>> contactList;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_type_menu);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
contactList = new ArrayList<>();
lv = (ListView) findViewById(R.id.list);
new GetContacts().execute();
// on seleting single product
// launching Edit Product Screen
lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
// getting values from selected ListItem
HashMap<String, String> selected = contactList.get(position);
String selectedId= selected.get("id");
Intent in = new Intent(getApplicationContext(), SubMenu.class);
// sending pid to next activity
in.putExtra("id",selectedId);
startActivityForResult(in, 100);
Toast.makeText(getApplicationContext(),"Toast" +selectedId ,Toast.LENGTH_SHORT).show();
}
});
}
/**
* Async task class to get json by making HTTP call
*/
private class GetContacts extends AsyncTask<Void, Void, Void> {
@Override
protected void onPreExecute() {
super.onPreExecute();
// Showing progress dialog
pDialog = new ProgressDialog(TypeMenu.this);
pDialog.setMessage("Please wait...");
pDialog.setCancelable(false);
pDialog.show();
// Toast.makeText(getApplicationContext(),"Toast",Toast.LENGTH_LONG).show();
}
@Override
protected Void doInBackground(Void... arg0) {
HttpHandler sh = new HttpHandler();
// Making a request to url and getting response
String jsonStr = sh.makeServiceCall(url);
Log.e(TAG, "Response from url: " + jsonStr);
if (jsonStr != null) {
try {
JSONArray jsonArry = new JSONArray(jsonStr);
for (int i = 0; i < jsonArry.length(); i++)
{
JSONObject c = jsonArry.getJSONObject(i);
String id = c.getString("id");
String type = c.getString("type");
HashMap<String, String> contact = new HashMap<>();
contact.put("id", id);
contact.put("type", type);
contactList.add(contact);
}
} catch (final JSONException e) {
Log.e(TAG, "Json parsing error: " + e.getMessage());
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(getApplicationContext(),
"Json parsing error: " + e.getMessage(),
Toast.LENGTH_LONG)
.show();
}
});
}
} else {
Log.e(TAG, "Couldn't get json from server.");
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(getApplicationContext(),
"Couldn't get json from server. Check LogCat for possible errors!",
Toast.LENGTH_LONG)
.show();
}
});
}
return null;
}
@Override
protected void onPostExecute(Void result) {
super.onPostExecute(result);
// Dismiss the progress dialog
if (pDialog.isShowing())
pDialog.dismiss();
/**
* Updating parsed JSON data into ListView
* */
ListAdapter adapter = new SimpleAdapter(
TypeMenu.this, contactList,
R.layout.list_item, new String[]{ "type","id"},
new int[]{
R.id.type});
lv.setAdapter(adapter);
}
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
onBackPressed();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
}
这是我的list_item.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal"
>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
>
<TextView
android:id="@+id/id"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="15dp"
/>
<TextView
android:id="@+id/type"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="10dp"
/>
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
>
<ImageView
android:id="@+id/arrow1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:paddingTop="10dp"
android:paddingRight="10dp"
android:paddingBottom="10dp"
/>
</LinearLayout>
</LinearLayout>
答案 0 :(得分：1)
试试这个：
这里是lsit_item.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView
android:id="@+id/id"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="15dp" />
<TextView
android:id="@+id/type"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="10dp" />
</LinearLayout>
<ImageView
android:id="@+id/arrow1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:paddingBottom="10dp"
android:paddingRight="10dp"
android:paddingTop="10dp"/>
</LinearLayout>
在您的活动中初始化此内容;
int[] images = new int[]{
R.drawable.dropdown,
};
// Keys used in Hashmap
String[] from = { "image","id","type" };
// Ids of views in listview_layout
int[] to = { R.id.arrow1,R.id.id,R.id.type};
在doInbanckground
for (int i = 0; i < jsonArry.length(); i++)
{
JSONObject c = jsonArry.getJSONObject(i);
String id = c.getString("id");
String type = c.getString("type");
HashMap<String, String> contact = new HashMap<>();
contact.put("id", id);
contact.put("type", type);
contact.put("image", Integer.toString(images[0]) );
contactList.add(contact);
}
同时在onPostExecute替换上面的代码中添加此内容：
ListAdapter adapter = new SimpleAdapter(
TypeMenu.this, contactList,
R.layout.list_item, from,to);
lv.setAdapter(adapter);
答案 1 :(得分：0)
您需要创建自定义RecylerView adapter
第1步：gradle：
dependencies {
...
compile "com.android.support:recyclerview-v7:23.0.1"
}
第2步：layout/activity_name.xml
<android.support.v7.widget.RecyclerView
android:id="@+id/my_recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scrollbars="vertical" />
第3步：创建自定义适配器
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
private ArrayList<String> mDataset;
// Provide a reference to the views for each data item
// Complex data items may need more than one view per item, and
// you provide access to all the views for a data item in a view holder
public class ViewHolder extends RecyclerView.ViewHolder {
// each data item is just a string in this case
public TextView txtHeader;
public TextView txtFooter;
public ViewHolder(View v) {
super(v);
txtHeader = (TextView) v.findViewById(R.id.firstLine);
txtFooter = (TextView) v.findViewById(R.id.secondLine);
}
}
public MyAdapter(ArrayList<String> myDataset) {
mDataset = myDataset;
}
// Create new views (invoked by the layout manager)
@Override
public MyAdapter.ViewHolder onCreateViewHolder(ViewGroup parent,
int viewType) {
// create a new view
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.rowlayout, parent, false);
// set the view's size, margins, paddings and layout parameters
ViewHolder vh = new ViewHolder(v);
return vh;
}
// Replace the contents of a view (invoked by the layout manager)
@Override
public void onBindViewHolder(ViewHolder holder, int position) {
// - get element from your dataset at this position
// - replace the contents of the view with that element
final String name = mDataset.get(position);
holder.txtHeader.setText(mDataset.get(position));
holder.txtHeader.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
remove(name);
}
});
holder.txtFooter.setText("Footer: " + mDataset.get(position));
}
// Return the size of your dataset (invoked by the layout manager)
@Override
public int getItemCount() {
return mDataset.size();
}
}
第4步：在activity.java
setContentView(R.layout.my_activity);
mRecyclerView = (RecyclerView) findViewById(R.id.my_recycler_view);
// use this setting to improve performance if you know that changes
// in content do not change the layout size of the RecyclerView
mRecyclerView.setHasFixedSize(true);
// use a linear layout manager
mLayoutManager = new LinearLayoutManager(this);
mRecyclerView.setLayoutManager(mLayoutManager);
// specify an adapter (see also next example)
mAdapter = new MyAdapter(myDataset);
mRecyclerView.setAdapter(mAdapter);