如何將textview中的值添加到列表視圖

Question

我試圖將textview中的值動態添加到listview中。爲此，我創建了另一個佈局以從用戶獲取值。但我無法做到這一點。我嘗試了很多東西。請幫助..這是我的代碼。 package com.example.chetan.assignment;

import android.content.Intent; 
import android.support.v7.app.AppCompatActivity; 
import android.os.Bundle; 
import android.view.View; 
import android.widget.ListAdapter; 
import android.widget.ListView; 

import java.util.ArrayList; 
import java.util.List; 


public class MainActivity extends AppCompatActivity { 
    private static int count = 0; 


    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 


     // String[] name= {"Apple","Banana","Mango","PineApple"}; 
     //String[] price = {"Rs.40","Rs.60","Rs.70","Rs.80"}; 

     List<String> names = new ArrayList<String>(); 
     //String[] names = {"names"}; 
     List<String> prices = new ArrayList<String>(); 
     //String[] prices = {"prices"}; 

     String name = getIntent().getStringExtra("name"); 
     String price = getIntent().getStringExtra("price"); 
     if(count==0) { 
      names.add(0, "name"); 
      prices.add(0, "price"); 
     } 

     if (count>0) { 
      names.add(count, name); 
      prices.add(count,price); 
     } 
     count++; 

     ListAdapter MyAdapter = new MyAdapter(names, prices, this); 
     ListView theList = (ListView) findViewById(R.id.listView); 

     theList.setAdapter(MyAdapter); 
    } 
    public void buttonClick(View view) { 
     Intent i = new Intent(this, Addlayout.class); 
     startActivity(i); 
    } 
} 


     package com.example.chetan.assignment; 




    package com.example.chetan.assignment; 

    import android.content.Context; 
    import android.view.LayoutInflater; 
    import android.view.View; 
    import android.view.ViewGroup; 
    import android.widget.ArrayAdapter; 
    import android.widget.BaseAdapter; 
    import android.widget.TextView; 

    class MyAdapter extends BaseAdapter { 

     String[] name; 
     String[] price; 
     Context context; 
     private static LayoutInflater myInflater = null; 

     public MyAdapter(String[] name, String[] price, Context context) { 
      this.name = name; 
      this.price = price; 
      this.context = context; 
      myInflater = (LayoutInflater)context. 
        getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
     } 
     @Override 
     public int getCount() { 
      return name.length; 
     } 

     @Override 
     public Object getItem(int position) { 
      return position; 
     } 

     @Override 
     public long getItemId(int position) { 
      return position; 
     } 
     public class Holder 
     { 
      TextView nametext; 
      TextView pricetext; 
     } 

     @Override 
     public View getView(int position, View convertView, ViewGroup parent) { 
      Holder myholder = new Holder(); 
      View myViews = myInflater.inflate(R.layout.myview,parent,false); 
      myholder.nametext= (TextView) myViews.findViewById(R.id.textView); 
      myholder.pricetext= (TextView) myViews.findViewById(R.id.textView2); 
      myholder.nametext.setText(name[position]); 
      myholder.pricetext.setText(price[position]); 

      return myViews; 

     } 

    } 
    package com.example.chetan.assignment; 

    import android.content.Intent; 
    import android.support.v7.app.AppCompatActivity; 
    import android.os.Bundle; 
    import android.text.Editable; 
    import android.view.View; 
    import android.widget.EditText; 
    import android.widget.Toast; 

    public class Addlayout extends AppCompatActivity { 


     @Override 
     protected void onCreate(Bundle savedInstanceState) { 
      super.onCreate(savedInstanceState); 
      setContentView(R.layout.activity_addlayout); 
     } 

     public void Onclickbutton(View view){ 
      EditText nametext = (EditText)findViewById(R.id.editText); 
      EditText pricetext = (EditText)findViewById(R.id.editText2); 

      String namedata = nametext.getText().toString(); 
      String pricedata = pricetext.getText().toString(); 

      Intent intent = new Intent(this,MainActivity.class); 
      intent.putExtra("name",namedata); 
      intent.putExtra("price",pricedata); 

      startActivity(intent); 

     } 
    } 

Answer 1

Here you can do something like this: 
    Instead of simple listview I have used RecyclerView as it has better performance. 

    //First create a Data class for name and price 

    public class Data implements Serializable { 

     private String name,price; 

     public Data(){} 

     public Data(String name,String price){ 
      this.name = name; 
      this.price = price; 
     } 

     public String getPrice() { 
      return price; 
     } 

     public void setPrice(String price) { 
      this.price = price; 
     } 

     public String getName() { 
      return name; 
     } 

     public void setName(String name) { 
      this.name = name; 
     } 
    } 


    //your Addlayout class 

    public class Addlayout extends AppCompatActivity { 

     List<Data> dataList = new ArrayList<>(); 
     @Override 
     protected void onCreate(Bundle savedInstanceState) { 
      super.onCreate(savedInstanceState); 
      setContentView(R.layout.activity_addlayout); 

     } 

     public void Onclickbutton(View view){ 
      EditText nameText = (EditText)findViewById(R.id.editText); 
      EditText priceText = (EditText)findViewById(R.id.editText2); 

      String nameData = nameText.getText().toString(); 
      String priceData = priceText.getText().toString(); 
      Data data = new Data(nameData, priceData); 
      dataList.add(data); 
      Intent intent = new Intent(this,MainActivity.class); 
      intent.putExtra("List", (Serializable) dataList); 
      startActivity(intent); 

     } 
    } 

    //add layout xml 
    //change layout according to you 

    <?xml version="1.0" encoding="utf-8"?> 
    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
     xmlns:tools="http://schemas.android.com/tools" 
     android:id="@+id/activity_addlayout" 
     android:layout_width="match_parent" 
     android:layout_height="match_parent" 
     android:paddingBottom="@dimen/activity_vertical_margin" 
     android:paddingLeft="@dimen/activity_horizontal_margin" 
     android:paddingRight="@dimen/activity_horizontal_margin" 
     android:paddingTop="@dimen/activity_vertical_margin" 
     tools:context="com.example.mmc.testproject.Addlayout"> 

     <EditText 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:inputType="textPersonName" 
      android:ems="10" 
      android:hint="name" 
      android:layout_alignParentTop="true" 
      android:layout_alignParentStart="true" 
      android:layout_marginStart="13dp" 
      android:id="@+id/editText" /> 

     <EditText 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:inputType="textPersonName" 
      android:ems="10" 
      android:hint="price" 
      android:layout_below="@+id/editText" 
      android:layout_alignEnd="@+id/editText" 
      android:layout_marginTop="18dp" 
      android:id="@+id/editText2" /> 

     <Button 
      android:text="Button" 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:layout_below="@+id/editText2" 
      android:layout_alignStart="@+id/editText2" 
      android:layout_marginStart="43dp" 
      android:layout_marginTop="36dp" 
      android:onClick="Onclickbutton" 
      android:id="@+id/button" /> 
    </RelativeLayout> 


    //Then your Listview Adapter 

    public class ListViewAdaptor extends RecyclerView.Adapter<ListViewAdaptor.MyViewHolder> { 
     private List<Data> mDataList; 

     public class MyViewHolder extends RecyclerView.ViewHolder{ 
      public TextView name,price; 

      public MyViewHolder(View view){ 
       super(view); 
       name = (TextView) view.findViewById(R.id.name); 
       price= (TextView) view.findViewById(R.id.price); 
      } 
     } 

     public ListViewAdaptor(List<Data> dataList){ 
      this.mDataList = dataList; 
     } 


     @Override 
     public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { 
      View itemView = LayoutInflater.from(parent.getContext()) 
        .inflate(R.layout.list_view_item, parent, false); 

      return new MyViewHolder(itemView); 
     } 

     @Override 
     public void onBindViewHolder(MyViewHolder holder, int position) { 
      Data data = mDataList.get(position); 
      holder.name.setText(data.getName()); 
      holder.price.setText(data.getPrice()); 
     } 

     @Override 
     public int getItemCount() { 
      return mDataList.size(); 
     } 
    } 


    //your Listview layout to show name and price 

    <?xml version="1.0" encoding="utf-8"?> 
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
     android:orientation="horizontal" 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content"> 

     <TextView 
      android:layout_width="match_parent" 
      android:layout_height="match_parent" 
      android:id="@+id/name" 
      android:text="name" 
      android:gravity="center" 
      android:textSize="26sp" 
      android:layout_weight="1"/> 

     <TextView 
      android:layout_width="match_parent" 
      android:layout_height="match_parent" 
      android:id="@+id/price" 
      android:text="price" 
      android:gravity="center" 
      android:textSize="26sp" 
      android:layout_weight="1"/> 

    </LinearLayout> 


    //And finally the main Activity 

    public class MainActivity extends AppCompatActivity { 


     private RecyclerView mRecyclerView; 
     private ListViewAdaptor mAdapter; 
     private List<Data> mDataList; 

     private static final String TAG = "MainActivity"; 
     @Override 
     protected void onCreate(Bundle savedInstanceState) { 
      super.onCreate(savedInstanceState); 
      setContentView(R.layout.activity_main); 

      mRecyclerView = (RecyclerView) findViewById(R.id.recycler_view); 
      Intent i = getIntent(); 
      mDataList = (List<Data>) i.getSerializableExtra("List"); 
      Log.e(TAG,"Datalist size : "+mDataList.size()); 
      mAdapter = new ListViewAdaptor(mDataList); 
      RecyclerView.LayoutManager mLayoutManager = new LinearLayoutManager(getApplicationContext()); 
      mRecyclerView.setLayoutManager(mLayoutManager); 
      mRecyclerView.setItemAnimator(new DefaultItemAnimator()); 
      mRecyclerView.setAdapter(mAdapter); 
     } 

    } 

//and main Activity.xml 

<?xml version="1.0" encoding="utf-8"?> 
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:tools="http://schemas.android.com/tools" 
    android:id="@+id/activity_main" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:paddingBottom="@dimen/activity_vertical_margin" 
    android:paddingLeft="@dimen/activity_horizontal_margin" 
    android:paddingRight="@dimen/activity_horizontal_margin" 
    android:paddingTop="@dimen/activity_vertical_margin" 
    tools:context="com.example.mmc.testproject.MainActivity"> 

    <android.support.v7.widget.RecyclerView 
     android:layout_width="match_parent" 
     android:layout_height="match_parent" 
     android:id="@+id/recycler_view"> 

    </android.support.v7.widget.RecyclerView> 

</RelativeLayout> 

希望它可以幫助！