Java 如何在列表视图中添加开关以及如何在新活动上打开和关闭状态
我想在下一个活动中关闭所有用户,但我无法这样做。我在Java 如何在列表视图中添加开关以及如何在新活动上打开和关闭状态,java,android,firebase,Java,Android,Firebase,我想在下一个活动中关闭所有用户,但我无法这样做。我在列表视图中为每个项目设置了开关,但我无法存储或获取每个项目的状态 我想向所有项目添加开关,并保存开关的所有状态。我想访问新活动中关闭开关的所有项目 这是adminhome.java文件,其中显示了此活动页面上的所有listview项: package com.example.nilesh.loginpa; import android.support.annotation.NonNull; import android.support.ann
列表视图中为每个项目设置了开关,但我无法存储或获取每个项目的状态
我想向所有项目添加开关,并保存开关的所有状态。我想访问新活动中关闭开关的所有项目
这是adminhome.java文件,其中显示了此活动页面上的所有listview项:
package com.example.nilesh.loginpa;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import android.widget.Switch;
import android.widget.TextView;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.database.ChildEventListener;
import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.ValueEventListener;
import java.util.ArrayList;
import java.util.List;
public class Adminhome extends AppCompatActivity {
FirebaseAuth firebaseauth;
DatabaseReference mref;
Button btn;
//private String uname;
//private ArrayList<String> ulist = new ArrayList<>();
List<UserProfile> userlist;
ListView allusers;
Switch switch1;
//private ArrayAdapter<String> arrayAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_adminhome);
//firebaseauth = FirebaseAuth.getInstance();
mref = FirebaseDatabase.getInstance().getReference("users");
btn = (Button) findViewById(R.id.btnsub);
allusers = (ListView) findViewById(R.id.lvusers);
userlist = new ArrayList<>();
//arrayAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1,ulist);
//allusers.setAdapter(arrayAdapter);
}
@Override
protected void onStart() {
super.onStart();
mref.addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
userlist.clear();
for (DataSnapshot userprofileSnapshot : dataSnapshot.getChildren()){
UserProfile userProfile = userprofileSnapshot.getValue(UserProfile.class);
userlist.add(userProfile);
}
Userslist adapter = new Userslist(Adminhome.this,userlist);
allusers.setAdapter(adapter);
}
@Override
public void onCancelled(@NonNull DatabaseError databaseError) {
}
});
}
}
请用这个例子。您需要具有具有所需列表项外观的XML布局(在本例中,列表项由textview和togglebutton组成):
私有类ShopItemListAdapter扩展了BaseAdapter{
私人物品清单;
专用ShopItemListAdapter(列出shopItems){
this.shopItems=shopItems;
}
@凌驾
public int getCount(){
return shopItems.size();
}
@凌驾
公共对象getItem(int位置){
返回商店物品。获取(位置);
}
@凌驾
公共长getItemId(int位置){
return shopItems.get(position.getId();
}
@凌驾
公共视图getView(最终整数位置、视图转换视图、视图组父视图){
ShopItem ShopItem=shopItems.get(位置);
if(convertView==null){
LayoutInflater LayoutInflater=getLayoutInflater();
convertView=LayoutFlater.充气(R.layout.shopitem,空);
TextView TextView=convertView.findViewById(R.id.shopItemText);
ToggleButton ToggleButton=convertView.findViewById(R.id.ShopItemBudden);
ViewHolder ViewHolder=新的ViewHolder(切换按钮,文本视图);
convertView.setTag(viewHolder);
}
ViewHolder ViewHolder=(ViewHolder)convertView.getTag();
//无论convertView是否为null,都必须始终设置click listener
//否则,循环视图的行为会与切换按钮的选中状态异常
viewHolder.shopItemBunded.setOnClickListener(新的ToggleBoughtListener(shopItem));
viewHolder.shopItemBuild.setChecked(shopItem.isBuild());
viewHolder.shopItemName.setText(shopItem.getName());
返回视图;
}
私有类视窗持有者{
切换按钮购物项目购买;
TextView shopItemName;
ViewHolder(切换按钮ShopItemBuild,TextView shopItemName){
this.shopitembunded=shopitembunded;
this.shopItemName=shopItemName;
}
}
私有类ToggleBoughtListener实现View.OnClickListener{
最终购物项目购物项目;
private ToggleBoughtListener(ShopItem ShopItem){
this.shopItem=shopItem;
}
@凌驾
公共void onClick(视图v){
shopItem.setBuund(!shopItem.isBuund());
存储库更新(shopItem);
}
}
}
我无法理解此代码,请您帮助我,我是androidYou的新手,您有ListView项目。此ListView需要适配器,它是BaseAdapter。此适配器将ListView与您的数据连接起来。方法getView返回每个项的列表项视图。ViewHolder模式可以帮助您调整性能,因为项目是循环使用的。好的,谢谢您,您能告诉我如何在关闭开关的新活动中获取项目吗
package com.example.nilesh.loginpa;
import android.app.Activity;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.CompoundButton;
import android.widget.Switch;
import android.widget.TextView;
import java.util.List;
public class Userslist extends ArrayAdapter <UserProfile> {
private Activity context;
private List<UserProfile> userlist;
public Userslist(Activity context,List<UserProfile> userlist){
super(context,R.layout.list_layout,userlist);
this.context =context;
this.userlist = userlist;
}
@NonNull
@Override
public View getView(int position, @Nullable View convertView, @NonNull ViewGroup parent) {
LayoutInflater inflater = context.getLayoutInflater();
View listViewItem = inflater.inflate(R.layout.list_layout, null, true);
TextView textViewName = (TextView) listViewItem.findViewById(R.id.textViewName);
TextView textViewemail = (TextView) listViewItem.findViewById(R.id.textViewemail);
Switch switch1 = (Switch) listViewItem.findViewById(R.id.switch1);
UserProfile userProfile = userlist.get(position);
textViewName.setText(userProfile.getName());
textViewemail.setText(userProfile.getEmail());
return listViewItem;
}
}
package com.example.nilesh.loginpa;
public class UserProfile {
public String name;
public String email;
public String age;
public UserProfile(){
}
public UserProfile(String name, String email, String age) {
this.name = name;
this.email = email;
this.age = age;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getAge() {
return age;
}
public void setAge(String age) {
this.age = age;
}
@Override
public String toString(){
return this.name + ":" + this.age;
}
}
private class ShopItemListAdapter extends BaseAdapter {
private List<ShopItem> shopItems;
private ShopItemListAdapter(List<ShopItem> shopItems) {
this.shopItems = shopItems;
}
@Override
public int getCount() {
return shopItems.size();
}
@Override
public Object getItem(int position) {
return shopItems.get(position);
}
@Override
public long getItemId(int position) {
return shopItems.get(position).getId();
}
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
ShopItem shopItem = shopItems.get(position);
if (convertView == null) {
LayoutInflater layoutInflater = getLayoutInflater();
convertView = layoutInflater.inflate(R.layout.shopitem, null);
TextView textView = convertView.findViewById(R.id.shopItemText);
ToggleButton toggleButton = convertView.findViewById(R.id.shopItemBought);
ViewHolder viewHolder = new ViewHolder(toggleButton, textView);
convertView.setTag(viewHolder);
}
ViewHolder viewHolder = (ViewHolder) convertView.getTag();
// click listener must be set always no matter of convertView is or is not null
// otherwise recycle view behaves strangely to checked states of toggle buttons
viewHolder.shopItemBought.setOnClickListener(new ToggleBoughtListener(shopItem));
viewHolder.shopItemBought.setChecked(shopItem.isBought());
viewHolder.shopItemName.setText(shopItem.getName());
return convertView;
}
private class ViewHolder {
ToggleButton shopItemBought;
TextView shopItemName;
ViewHolder(ToggleButton shopItemBought, TextView shopItemName) {
this.shopItemBought = shopItemBought;
this.shopItemName = shopItemName;
}
}
private class ToggleBoughtListener implements View.OnClickListener {
final ShopItem shopItem;
private ToggleBoughtListener(ShopItem shopItem) {
this.shopItem = shopItem;
}
@Override
public void onClick(View v) {
shopItem.setBought(!shopItem.isBought());
repository.update(shopItem);
}
}
}