如何将值返回到getintent和puttynts之间的参数

Question

我有这个产品getters和setters我想要下面的布尔值（boolean = added）在点击时更改为true，当它再次点击时返回false。下面的详细信息：下面的代码是在信息被存储并且被转移到一个列表视图

package kfc.project; 

import java.util.ArrayList; 

public class ProductList { 
    ArrayList<Product> list; 


    public ProductList(){ 
     list = new ArrayList<Product>(); 

     //CREATE PRODUCT HERE 
     Product chicken; 
     list.add(new Product("Chicken", 10, 20, 30, 40, 50, 60, 70, 80, 90, 80,70,60,50,40,30));  

     Product rice; 
     list.add(new Product("Rice",11)); 
    } 

    public String[] getNames(){ 
     int c = 0; 
     int size = list.size() - 1; 
     String[] names = new String[size]; 

     while (size >= c) { 
      //names.add(list.get(c).getName()); 
      names[c] = list.get(c).getName(); 
      c++; 
     } 

     c = 0; 

     return names; 
    } 

    public ArrayList<Product> getList(){ 
     return list; 
    } 

} 

这里getter和setter

package kfc.project; 

    public class Product { 


     String name; 
     int servingSize; 
     int calories; 
     int fat; 
     int saturatedFat; 
     int transFat; 
     int cholesterol; 
     int sodium; 
     int carbs; 
     int fiber; 
     int sugar; 
     int protein; 
     int vitamina; 
     int vitaminc; 
     int calcium; 
     int iron; 
     boolean added; 

     public Product (String name, int servingSize, int calories, int fat, int saturatedFat, int transFat, int cholesterol, int sodium, int carbs, int fiber, int sugar, int protein, int vitamina, int vitaminc, int calcium, int iron){ 
      this.name=name; 
      this.calories=calories; 
      this.servingSize=servingSize; 
      this.fat=fat; 
      this.saturatedFat=saturatedFat; 
      this.transFat=transFat; 
      this.cholesterol=cholesterol; 
      this.fiber=fiber; 
      this.sugar=sugar; 
      this.sodium=sodium; 
      this.carbs=carbs; 
      this.protein=protein; 
      this.vitamina=vitamina; 
      this.vitaminc=vitaminc; 
      this.calcium=calcium; 
      this.iron=iron; 
      added = false; 
     } 

     @Override 
     public String toString(){ 

       return name; 

     } 

     public Product (String name, int servingSize){ 
      this.name=name; 
      this.servingSize=servingSize; 
     } 

     public String getName() { 
      return name; 
     } 

     public int getServingSize() { 
      return servingSize; 
     } 

     public int getCalories() { 
      return calories; 
     } 

     public int getFat() { 
      return fat; 
     } 

     public int getSaturatedFat() { 
      return saturatedFat; 
     } 

     public int getTransFat() { 
      return transFat; 
     } 

     public int getCholesterol() { 
      return cholesterol; 
     } 

     public int getSodium() { 
      return sodium; 
     } 

     public int getCarbs() { 
      return carbs; 
     } 

     public int getProtein() { 
      return protein; 
     } 

     public int getFiber(){ 
      return fiber; 
     } 

     public int getSugar(){ 
      return sugar; 
     } 
     public int getVitaminA(){ 
      return vitamina; 
     } 
     public int getVitaminC(){ 
      return vitaminc; 
     } 
     public int getCalcium(){ 
      return calcium; 
     } 
     public int getIron(){ 
      return iron; 
     } 
     public void setAdded(boolean x){ 
      added = x; 
     } 
     public boolean getAdded(){ 
      return added; 
     } 

    } 

这是数组列表是针对列表视图的代码，其中有是它转移到XML文件所在

package kfc.project; 

import java.util.ArrayList; 

import android.app.Activity; 
import android.app.ListActivity; 
import android.content.Context; 
import android.content.Intent; 
import android.os.Bundle; 
import android.view.View; 
import android.widget.AdapterView; 
import android.widget.AdapterView.OnItemClickListener; 
import android.widget.ArrayAdapter; 
import android.widget.Button; 
import android.widget.ListView; 
import android.widget.Toast; 

public class ProductListView extends ListActivity { 

    /** Called when the activity is first created. */ 
    @Override 
    public void onCreate(Bundle savedInstanceState) {  
     super.onCreate(savedInstanceState); 

     final ProductList pl = new ProductList(); 

     //setListAdapter(new ArrayAdapter<String>(this, R.layout.list_item, PRODUCTS)); 
     setListAdapter(new ArrayAdapter<Product>(this, R.layout.list_item, pl.getList())); 

     ListView lv = getListView(); 
     lv.setTextFilterEnabled(true); 

     lv.setOnItemClickListener(new OnItemClickListener() { 

      public void onItemClick(AdapterView<?> parent, View view, int position, long id) { 

      // When clicked, show a toast with the TextView text 
      Toast.makeText(getApplicationContext(), "View Product", Toast.LENGTH_SHORT).show(); 

      Product product = pl.getList().get(position); 
      // intent stuff for product detail 
      Intent intent = new Intent(ProductListView.this, productdetail.class); 
      //!!!!!!!!!!!!!!!!!!!!!!!!!! 
      //intent.putCharSequenceArrayListExtra("list", pl.getList()); 
      intent.putExtra("name",product.getName()); 
      intent.putExtra("serving size", product.getServingSize()); 
      intent.putExtra("calories", product.getCalories()); 
      intent.putExtra("fat", product.getFat()); 
      intent.putExtra("saturated fat", product.getSaturatedFat()); 
      intent.putExtra("trans fat", product.getTransFat()); 
      intent.putExtra("cholesterol", product.getCholesterol()); 
      intent.putExtra("sodium", product.getSodium()); 
      intent.putExtra("carbs", product.getCarbs()); 
      intent.putExtra("fiber", product.getFiber()); 
      intent.putExtra("sugar", product.getSugar()); 
      intent.putExtra("protein", product.getProtein()); 
      intent.putExtra("vitamina", product.getVitaminA()); 
      intent.putExtra("vitaminc", product.getVitaminC()); 
      intent.putExtra("calcium", product.getCalcium()); 
      intent.putExtra("iron", product.getIron()); 
      intent.putExtra("added", product.getAdded()); 

      ProductListView.this.startActivity(intent); 

      //startActivity(new Intent("kfc.project.productdetail")); 
      } 

     }); 

    } 

} 

现在，这是XML的Java文件，其中我想定义布尔每当BU另一个Java文件的意图tton被点击。我怎样才能做到这一点

package kfc.project; 

import android.app.Activity; 
import android.content.Intent; 
import android.os.Bundle; 
import android.view.View; 
import android.widget.Button; 
import android.widget.EditText; 
import android.widget.TextView; 

public class productdetail extends Activity{ 

    @Override 
    protected void onCreate(Bundle bundle) { 
     // TODO Auto-generated method stub 
     super.onCreate(bundle); 
     setContentView(R.layout.productdetail); 
     //stuff to get intent 
     Intent receivedIntent = getIntent(); 


     String productName = receivedIntent.getStringExtra("name"); 
     int productServingSize = receivedIntent.getIntExtra("serving size",0); 
     int productCalories = receivedIntent.getIntExtra("calories",0); 
     int productFat = receivedIntent.getIntExtra("fat",0); 
     int productSaturatedFat = receivedIntent.getIntExtra("saturated fat",0); 
     int productTransFat = receivedIntent.getIntExtra("trans fat",0); 
     int productCholesterol = receivedIntent.getIntExtra("cholesterol",0); 
     int productSodium = receivedIntent.getIntExtra("sodium",0); 
     int productCarbs = receivedIntent.getIntExtra("carbs",0); 
     int productFiber = receivedIntent.getIntExtra("fiber",0); 
     int productSugar = receivedIntent.getIntExtra("sugar",0); 
     int productProtein = receivedIntent.getIntExtra("protein",0); 
     int productVitaminA = receivedIntent.getIntExtra ("vitamina",0); 
     int productVitaminC = receivedIntent.getIntExtra ("vitaminc",0); 
     int productCalcium = receivedIntent.getIntExtra ("calcium",0); 
     int productIron = receivedIntent.getIntExtra ("iron",0); 
     boolean added = receivedIntent.getBooleanExtra("added", false); 

     //BUTTONS 
     Button addButton = (Button) findViewById(R.id.button1); 
     Button removeButton = (Button) findViewById(R.id.button3); 

     Bundle extras = getIntent().getExtras(); 

     String name = extras.getString("name"); 

     if (name != null) { 
      TextView text1 = (TextView) findViewById(R.id.productname); 
      text1.setText(productName); 

     } 

     //SHOW/HIDE 'ADD' & 'REMOVE' BUTTONS 
     if (added==false) { 
      //HIDE 'REMOVE' BUTTON 
      removeButton.setVisibility(View.GONE); 
      //SHOW 'ADD' BUTTON 
      addButton.setVisibility(View.VISIBLE); 
     }else{ 
      //SHOW 'REMOVE' BUTTON 
      removeButton.setVisibility(View.VISIBLE); 
      //HIDE 'ADD' BUTTON   
      addButton.setVisibility(View.GONE); 
     } 

     addButton.setOnClickListener(new View.OnClickListener() { 

      public void onClick(View v) { 
       // TODO Auto-generated method stub 
       //added=true; 
      }  
     }); 

     removeButton.setOnClickListener(new View.OnClickListener() { 

      public void onClick(View v) { 
       // TODO Auto-generated method stub 
       //added=false; 
      }  
     }); 


      TextView text2 = (TextView) findViewById(R.id.servingsize); 
      text2.setText(""+productServingSize); 

      TextView text3 = (TextView) findViewById(R.id.calories); 
      text3.setText(""+productCalories); 

      TextView text4 = (TextView) findViewById(R.id.totalfat); 
      text4.setText(""+productFat); 

      TextView text5 = (TextView) findViewById(R.id.saturatedfat); 
      text5.setText(""+productSaturatedFat); 

      TextView text6 = (TextView) findViewById(R.id.transfat); 
      text6.setText(""+productTransFat); 

      TextView text7 = (TextView) findViewById(R.id.cholesterol); 
      text7.setText(""+productCholesterol); 

      TextView text8 = (TextView) findViewById(R.id.sodium); 
      text8.setText(""+productSodium); 

      TextView text9 = (TextView) findViewById(R.id.totalcarbohydrates); 
      text9.setText(""+productCarbs); 

      TextView text10 = (TextView) findViewById(R.id.fiber); 
      text10.setText(""+productFiber); 

      TextView text11 = (TextView) findViewById(R.id.sugar); 
      text11.setText(""+productSugar); 

      TextView text12 = (TextView) findViewById(R.id.protein); 
      text12.setText(""+productProtein); 

      TextView text13 = (TextView) findViewById(R.id.vitamina); 
      text13.setText(""+productVitaminA); 

      TextView text14 = (TextView) findViewById(R.id.vitaminc); 
      text14.setText(""+productVitaminC); 

      TextView text15 = (TextView) findViewById(R.id.calcium); 
      text15.setText(""+productCalcium); 

      TextView text16 = (TextView) findViewById(R.id.iron); 
      text16.setText(""+productIron); 




     /* 
     Intent intent = getIntent(); 
     String str = intent.getStringExtra("name");*/ 

    } 





} 

Answer 1

首先，如果你想通过这种在你现在正在做的方式活动之间的信息，你应该让你的产品类Parcelable和手工传递对象，而不是按照你现在所做的方式设置所有的标志。

然后，一旦您在productdetail活动中检索产品，就会在对象上使用getter和setter，并且一旦用户完成，就会将其传回您之前的活动。

但是，做你想做的事情的正确方法是使用Content Providers：intents不应该被用来传递活动之间的产品等持久性信息。