我的列表,ScrollView和按钮出错

时间:2012-09-03 05:35:16

标签: android listview button android-activity scrollview

我是Android开发的新手,所以我只想询问我如何正确地做这些事情。我已经制作了一个购物清单应用程序,它将显示数量,项目名称和状态(复选框)。这是我的问题:

Here is my error screenshot

  1. 列表中的项目或项目名称未显示。
  2. 标题(QUANTITY,ITEM和STATUS)和按钮(添加,删除)正在重复,应该不是。
  3. 最后,我应该在哪里放置按钮代码(additem)以使其达到预期的布局。它会出现在GroceryListActivity类还是Grocery类中?
  4. 如果我有这么多问题,我很抱歉,如果你能帮忙回答这些问题,我将不胜感激。谢谢! :)

    杂货店型号

    public class Grocery{
    
         private String quantity;
         private String item;
         private boolean selected;
    
            //quantity
    
          public Grocery(String quantity, String item) {
            this.quantity = quantity;
            selected = false;
          }
    
            public String getQuantity() {
                return quantity;
            }
    
              public void setQuantity(String quantity) {
                this.quantity = quantity;
              }
    
              //item
    
          public Grocery(String item) {
                this.item = item;
                selected = false;
              }
    
              public String getItem() {
                return item;
              }
    
              public void setItem(String item) {
                this.item = item;
              }
    
              //chckbox
    
          public boolean isSelected() {
            return selected;
          }
    
              public void setSelected(boolean selected) {
                this.selected = selected;
              }
    
    }
    

    GroceryList活动

    import java.util.ArrayList;
    import java.util.List;
    import android.app.AlertDialog;
    import android.app.ListActivity;
    import android.content.DialogInterface;
    import android.content.Intent;
    import android.os.Bundle;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.widget.ArrayAdapter;
    import android.widget.Button;
    import android.widget.Toast;
    
    public class GroceryListActivity extends ListActivity implements OnClickListener{
    
    
    /** Called when the activity is first created. */
    
      public void onCreate(Bundle icicle) {
        super.onCreate(icicle);
        // Create an array of Strings, that will be put to our ListActivity
        ArrayAdapter<Grocery> adapter = new ArrayAdapterGroceryList(this, getGrocery());
        setListAdapter(adapter);
      }
    
      private List<Grocery> getGrocery() {
        List<Grocery> list = new ArrayList<Grocery>();
            list.add(get("1", "Soy Sauce"));
            list.add(get("2", "Cabbage"));
            list.add(get("3", "Potato"));
            list.add(get("4", "Bell Pepper"));
        // Initially select one of the items
            list.get(1).setSelected(false);
        return list;
      }
    
      private Grocery get(String q, String i) {
        return new Grocery(q, i);
      }
    
    
         public void onCreate1(Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
                setContentView(R.layout.addgrocery);
    
                Button addItem_btn = (Button) findViewById(R.id.addItem);
                addItem_btn.setOnClickListener((OnClickListener) this);
    
                Button delete_btn = (Button) findViewById(R.id.deleteItem);
                delete_btn.setOnClickListener(this);
    
         }
    
    
    
        public void onClick(View v) {
            // TODO Auto-generated method stub
            switch (v.getId()) {
    
            case R.id.addItem:
                Intent a = new Intent(this, AddGrocery.class);
                startActivity(a);
                break;
    
            case R.id.deleteItem:
                AlertDialog.Builder Builder = new AlertDialog.Builder(this);
                Builder.setTitle("Confirm Delete.");
                Builder.setMessage("Are you sure you want to delete selected items?");
                Builder.setPositiveButton("Yes", new DialogInterface.OnClickListener() {                
                    public void onClick(DialogInterface dialog, int which) {
                        Toast.makeText(getApplicationContext(), "You clicked on YES", Toast.LENGTH_SHORT).show();
                    }
                });
                Builder.setNegativeButton("No", new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int which) {
                        Toast.makeText(getApplicationContext(), "You clicked on NO", Toast.LENGTH_SHORT).show();
                        dialog.cancel();
                    }
                });
                Builder.show();
                break;
            }
        }
    
    } 
    

    阵列适配器

    import java.util.List;
    import android.app.Activity;
    import android.view.LayoutInflater;
    import android.view.View;
    import android.view.ViewGroup;
    import android.widget.ArrayAdapter;
    import android.widget.CheckBox;
    import android.widget.CompoundButton; 
    import android.widget.TextView;
    
    public class ArrayAdapterGroceryList extends ArrayAdapter<Grocery> {
    
    private final List<Grocery> list;
    private final Activity context;
    
    public ArrayAdapterGroceryList(Activity context, List<Grocery> list) {
    super(context, R.layout.grocery, list);
    this.context = context;
    this.list = list;
    }
    
    static class ViewHolder {
    protected TextView itemQty;
    protected TextView itemName;
    protected CheckBox chkItem;
    public TextView textQty;
    public TextView textName;
    public CheckBox checkbox;
    }
    
    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
    View view = null;
    if (convertView == null) {
      LayoutInflater inflator = context.getLayoutInflater();
      view = inflator.inflate(R.layout.grocery, null);
      final ViewHolder viewHolder = new ViewHolder();
          viewHolder.textQty = (TextView) view.findViewById(R.id.itemQty);
          viewHolder.textName = (TextView) view.findViewById(R.id.itemName);
          viewHolder.checkbox = (CheckBox) view.findViewById(R.id.chkItem);
          viewHolder.checkbox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
    
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
              Grocery element = (Grocery) viewHolder.checkbox.getTag();
              element.setSelected(buttonView.isChecked());
    
            }
          });
      view.setTag(viewHolder);
      viewHolder.checkbox.setTag(list.get(position));
    } else {
          view = convertView;
          ((ViewHolder) view.getTag()).checkbox.setTag(list.get(position));
        }
        ViewHolder holder = (ViewHolder) view.getTag();
        holder.textQty.setText(list.get(position).getQuantity());
        holder.textName.setText(list.get(position).getItem());
        holder.checkbox.setChecked(list.get(position).isSelected());
    return view;
     }
    } 
    

    我的XML文件

    <?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="@layout/bg_list"
    android:orientation="vertical"
    android:weightSum="1.0">
    
    
    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" 
        android:weightSum="3"
        android:gravity="center"
        android:background="@layout/bg_box">
    
            <TextView
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:gravity="center_horizontal"
                android:text="QTY"
                android:textColor="#ffffff"
                android:textSize="20dp"
                android:textStyle="bold"
                android:layout_weight="1" />
    
            <TextView
                android:id="@+id/serialNumberView"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:gravity="center_horizontal"
                 android:layout_weight="1" 
                 android:text="ITEM"
                 android:textStyle="bold"
                 android:textColor="#ffffff"
                android:textSize="20dp"/>
    
            <TextView
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:gravity="center_horizontal"
                android:text="STATUS"
                android:textStyle="bold"
                android:textColor="#ffffff"
                android:textSize="20dp"
                android:layout_weight="1" />
            </LinearLayout>
    
    <ScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="1" >
    
       <LinearLayout
            android:layout_width="fill_parent"
            android:layout_height="wrap_content" 
            android:orientation="horizontal"
            android:layout_weight="1"
            android:paddingTop="5dp"
            android:gravity="center_horizontal">
    
          <TextView android:id="@+id/itemQty"
             android:layout_width="30dp"
             android:layout_height="fill_parent"
             android:paddingLeft="20dp"
             android:textColor="#FFFFFF"
             android:textSize="15dp"/>
    
         <TextView android:id="@+id/itemName"
             android:layout_width="200dp"
             android:layout_height="fill_parent"
             android:textColor="#FFFFFF"
             android:textSize="15dp"/>
    
         <CheckBox 
            android:id="@+id/chkItem"
            android:layout_width="50dp"
            android:layout_height="fill_parent"/>
    
       </LinearLayout>
    
    </ScrollView>
    
    
    
     <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:layout_gravity="bottom">
    
        <Button
            android:id="@+id/addItem"
            android:layout_width="0dp"
            android:layout_height="fill_parent"
            android:text="Add"
            android:layout_weight="1" />
    
        <Button
            android:id="@+id/deleteItem"
            android:layout_width="0dp"
            android:layout_height="fill_parent"
            android:text="Delete"
            android:layout_weight="1" />
    </LinearLayout> 
    

1 个答案:

答案 0 :(得分:4)

正如我从 GroceryListActivity 代码中注意到的那样,

public void onCreate1(Bundle savedInstanceState) {

public void onCreate(Bundle icicle) {

已删除,

public void onCreate1(Bundle savedInstanceState) { } method... 

并将代码从onCreate()

中删除

类似的东西,

public void onCreate(Bundle icicle) {
    super.onCreate(icicle);

    setContentView(R.layout.addgrocery);

    Button addItem_btn = (Button) findViewById(R.id.addItem);
    addItem_btn.setOnClickListener((OnClickListener) this);

    Button delete_btn = (Button) findViewById(R.id.deleteItem);
    delete_btn.setOnClickListener(this);

    // Create an array of Strings, that will be put to our ListActivity
    ArrayAdapter<Grocery> adapter = new ArrayAdapterGroceryList(this, getGrocery());
    setListAdapter(adapter);
  }