我想为列表视图创建一个自定义适配器。有没有任何文章可以告诉我如何创建一个,并解释它是如何工作的?
当前回答
import android.app.Activity;
import android.content.Context;
import android.text.Html;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;
import org.json.JSONObject;
import java.util.ArrayList;
public class OurteamAdapter extends BaseAdapter {
Context cont;
ArrayList<OurteamModel> llist;
OurteamAdapter madap;
LayoutInflater inflater;
JsonHelper Jobj;
String Id;
JSONObject obj = null;
int position = 0;
public OurteamAdapter(Context c,ArrayList<OurteamModel> Mi)
{
this.cont = c;
this.llist = Mi;
}
@Override
public int getCount()
{
// TODO Auto-generated method stub
return llist.size();
}
@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return llist.get(position);
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
@Override
public View getView(final int position, View convertView, ViewGroup parent)
{
// TODO Auto-generated method stub
if(convertView == null)
{
LayoutInflater in = (LayoutInflater) cont.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
convertView = in.inflate(R.layout.doctorlist, null);
}
TextView category = (TextView) convertView.findViewById(R.id.button1);
TextView title = (TextView) convertView.findViewById(R.id.button2);
ImageView i1=(ImageView) convertView.findViewById(R.id.imageView1);
category.setText(Html.fromHtml(llist.get(position).getGalleryName()));
title.setText(Html.fromHtml(llist.get(position).getGalleryDetail()));
if(llist.get(position).getImagesrc()!=null)
{
i1.setImageBitmap(llist.get(position).getImagesrc());
}
else
{
i1.setImageResource(R.drawable.anandlogo);
}
return convertView;
}
}
其他回答
public class CustomAdapter extends BaseAdapter{
ArrayList<BookPojo> data;
Context ctx;
int index=0;
public CustomAdapter(ArrayList<BookPojo> data, Context ctx) {
super();
this.data = data;
this.ctx = ctx;
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return data.size();
}
@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return data.get(position);
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return position;
}
@Override
public View getView(int position, View convertview, ViewGroup parent) {
// TODO Auto-generated method stub
View v=convertview;
if(v==null){
LayoutInflater vi=LayoutInflater.from(ctx);
v=vi.inflate(R.layout.messgeview,null);
}
RelativeLayout rlmessage=(RelativeLayout)v.findViewById(R.id.rlmessgeview);
TextView tvisdn=(TextView)v.findViewById(R.id.tvisdn);
TextView tvtitle=(TextView)v.findViewById(R.id.tvtitle);
TextView tvauthor=(TextView)v.findViewById(R.id.tvauthor);
TextView tvprice=(TextView)v.findViewById(R.id.tvprice);
BookPojo bpj=data.get(position);
tvisdn.setText(bpj.isdn+"");
tvtitle.setText(bpj.title);
tvauthor.setText(bpj.author);
tvprice.setText(bpj.price+"");
if(index%2==0)
{
rlmessage.setBackgroundColor(Color.BLUE);
}
else
{
rlmessage.setBackgroundColor(Color.YELLOW);
}
index++;
return v;
}
}
这很简单。
import android.content.Context;
import android.content.DialogInterface;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v7.app.AlertDialog;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
import java.util.List;
/**
* Created by Belal on 9/14/2017.
*/
//we need to extend the ArrayAdapter class as we are building an adapter
public class MyListAdapter extends ArrayAdapter<Hero> {
//the list values in the List of type hero
List<Hero> heroList;
//activity context
Context context;
//the layout resource file for the list items
int resource;
//constructor initializing the values
public MyListAdapter(Context context, int resource, List<Hero> heroList) {
super(context, resource, heroList);
this.context = context;
this.resource = resource;
this.heroList = heroList;
}
//this will return the ListView Item as a View
@NonNull
@Override
public View getView(final int position, @Nullable View convertView, @NonNull ViewGroup parent) {
//we need to get the view of the xml for our list item
//And for this we need a layoutinflater
LayoutInflater layoutInflater = LayoutInflater.from(context);
//getting the view
View view = layoutInflater.inflate(resource, null, false);
//getting the view elements of the list from the view
ImageView imageView = view.findViewById(R.id.imageView);
TextView textViewName = view.findViewById(R.id.textViewName);
TextView textViewTeam = view.findViewById(R.id.textViewTeam);
Button buttonDelete = view.findViewById(R.id.buttonDelete);
//getting the hero of the specified position
Hero hero = heroList.get(position);
//adding values to the list item
imageView.setImageDrawable(context.getResources().getDrawable(hero.getImage()));
textViewName.setText(hero.getName());
textViewTeam.setText(hero.getTeam());
//adding a click listener to the button to remove item from the list
buttonDelete.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//we will call this method to remove the selected value from the list
//we are passing the position which is to be removed in the method
removeHero(position);
}
});
//finally returning the view
return view;
}
//this method will remove the item from the list
private void removeHero(final int position) {
//Creating an alert dialog to confirm the deletion
AlertDialog.Builder builder = new AlertDialog.Builder(context);
builder.setTitle("Are you sure you want to delete this?");
//if the response is positive in the alert
builder.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
//removing the item
heroList.remove(position);
//reloading the list
notifyDataSetChanged();
}
});
//if response is negative nothing is being done
builder.setNegativeButton("No", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
}
});
//creating and displaying the alert dialog
AlertDialog alertDialog = builder.create();
alertDialog.show();
}
}
来源:自定义ListView Android教程
一个更紧凑的自定义适配器的例子(使用列表数组作为我的数据):
class MyAdapter extends ArrayAdapter<Object> {
public ArrayAdapter(Context context, List<MyObject> objectList) {
super(context, R.layout.my_list_item, R.id.textViewTitle, objectList.toArray());
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View row = super.getView(position, convertView, parent);
TextView title = (TextView) row.findViewById(R.id.textViewTitle);
ImageView icon = (ImageView) row.findViewById(R.id.imageViewAccessory);
MyObject obj = (MyObject) getItem(position);
icon.setImageBitmap( ... );
title.setText(obj.name);
return row;
}
}
下面是如何使用它:
List<MyObject> objectList = ...
MyAdapter adapter = new MyAdapter(this.getActivity(), objectList);
listView.setAdapter(adapter);
检查这个链接,在非常简单的通过convertView,我们可以得到一行的布局,这将显示在listview(这是parentView)。
View v = convertView;
if (v == null) {
LayoutInflater vi;
vi = LayoutInflater.from(getContext());
v = vi.inflate(R.layout.itemlistrow, null);
}
使用position,你可以得到List<Item>的对象。
Item p = items.get(position);
在此之后,我们必须将对象的所需细节设置为标识的表单小部件。
if (p != null) {
TextView tt = (TextView) v.findViewById(R.id.id);
TextView tt1 = (TextView) v.findViewById(R.id.categoryId);
TextView tt3 = (TextView) v.findViewById(R.id.description);
if (tt != null) {
tt.setText(p.getId());
}
if (tt1 != null) {
tt1.setText(p.getCategory().getId());
}
if (tt3 != null) {
tt3.setText(p.getDescription());
}
}
然后它将返回构造的视图,该视图将附加到parentView(这是一个ListView/GridView)。
public class ListAdapter extends ArrayAdapter<Item> {
private int resourceLayout;
private Context mContext;
public ListAdapter(Context context, int resource, List<Item> items) {
super(context, resource, items);
this.resourceLayout = resource;
this.mContext = context;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View v = convertView;
if (v == null) {
LayoutInflater vi;
vi = LayoutInflater.from(mContext);
v = vi.inflate(resourceLayout, null);
}
Item p = getItem(position);
if (p != null) {
TextView tt1 = (TextView) v.findViewById(R.id.id);
TextView tt2 = (TextView) v.findViewById(R.id.categoryId);
TextView tt3 = (TextView) v.findViewById(R.id.description);
if (tt1 != null) {
tt1.setText(p.getId());
}
if (tt2 != null) {
tt2.setText(p.getCategory().getId());
}
if (tt3 != null) {
tt3.setText(p.getDescription());
}
}
return v;
}
}
这是我在项目中使用的一个类。你需要有一个你想要显示的项目的集合,在我的例子中是<Item>。你需要重写View getView(int position, View convertView, ViewGroup parent)方法。
itemlistrow定义了ListView的行。
<?xml version="1.0" encoding="utf-8"?>
<TableLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_height="wrap_content" android:orientation="vertical"
android:layout_width="fill_parent">
<TableRow android:layout_width="fill_parent"
android:id="@+id/TableRow01"
android:layout_height="wrap_content">
<TextView android:textColor="#FFFFFF"
android:id="@+id/id"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="id" android:textStyle="bold"
android:gravity="left"
android:layout_weight="1"
android:typeface="monospace"
android:height="40sp" />
</TableRow>
<TableRow android:layout_height="wrap_content"
android:layout_width="fill_parent">
<TextView android:textColor="#FFFFFF"
android:id="@+id/categoryId"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="categoryId"
android:layout_weight="1"
android:height="20sp" />
<TextView android:layout_height="wrap_content"
android:layout_width="fill_parent"
android:layout_weight="1"
android:textColor="#FFFFFF"
android:gravity="right"
android:id="@+id/description"
android:text="description"
android:height="20sp" />
</TableRow>
</TableLayout>
在MainActivity中定义listview,
ListView yourListView = (ListView) findViewById(R.id.itemListView);
// get data from the table by the ListAdapter
ListAdapter customAdapter = new ListAdapter(this, R.layout.itemlistrow, List<yourItem>);
yourListView .setAdapter(customAdapter);
推荐文章
- Android:垂直对齐多行EditText(文本区域)
- Android无尽列表
- Android room persistent: AppDatabase_Impl不存在
- 错误:执行失败的任务':app:compileDebugKotlin'。>编译错误。详细信息请参见日志
- 在Android中使用URI生成器或使用变量创建URL
- 缩放图像以填充ImageView宽度并保持纵横比
- 列表视图的自定义适配器
- 在Android中设置TextView span的颜色
- 如何以编程方式在RelativeLayout中布局视图?
- Android Facebook集成无效键散列
- 什么是“android. r.b ayout.simple_list_item_1”?
- 将字符串转换为Uri
- 在Android中创建临时文件
- INSTALL_PARSE_FAILED_NO_CERTIFICATES错误是什么?
- 在Android中定义RelativeLayout视图的Z顺序