朋友我是Android的新手并且自己学习。我正在为学习创建发票管理器应用程序。这里的产品由管理员添加,工作正常。用户只有创建发票的权限。当用户进入create_invoice活动时,他有一组框架布局,其中一个用于添加项目。当用户按下框架布局时,他会看到另一个活动,他可以在列表视图中找到所有列表项以及管理员已添加的产品价格。现在,当用户按下某个项目时,他再次返回到create_invoice活动,并出现一个警告框,询问所需的数量。当用户输入数量并单击“确定”按钮时,对于第一个,列表项将根据需要正确显示。但是当我添加第二项时,第一项被替换。所以现在我的问题是如何解决这个问题..伙计们请帮助我。你发现的代码可能非常愚蠢,但我还在学习。提前谢谢。
//data from activity invoice add_item
product_name = intent.getStringExtra("product_name");
product_price = intent.getDoubleExtra("product_price",0);
//product_qty = intent.getIntExtra("product_qty",0);
product_code = intent.getIntExtra("product_code",0);
if(product_name!= null && product_price!= 0 && product_code!= 0)
{
try {
builder = new AlertDialog.Builder(this);
builder.setTitle("Product Qty");
layoutInflater = LayoutInflater.from(Create_invoice.this);
view = layoutInflater.inflate(R.layout.dialoglayout_invoice,null);
builder.setView(view);
builder.setPositiveButton("OK", new DialogInterface.OnClickListener(){
@Override
public void onClick(DialogInterface dialog, int which) {
EditText etxt_dialog_qty=(EditText)view.findViewById(R.id.
etxt_dialog_qty);
int qty = Integer. parseInt (etxt_dialog_qty.getText().
toString().trim());
invoice_product_list products = new invoice_product_list
(product_name, product_price, qty, product_code);
//arraylist
ArrayList<invoice_product_list> productList = new ArrayList<>();
//customAdapter
customAdapterInvoice = new custom_adapter_invoice
(Create_invoice.this, productList);
customAdapterInvoice.add(products);
customAdapterInvoice.notifyDataSetChanged();
//listview in create_invoice activity
listView_additem = (ListView)
findViewById(R.id.listview_additem);
listView_additem.setAdapter(customAdapterInvoice);
alertDialog.dismiss();
}
});
builder.setNegativeButton("Cancel", new
DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
alertDialog.dismiss();
}
});
alertDialog = builder.create();
alertDialog.show();
}
catch (Exception e)
{
System.out.print(e);
}
}
public class custom_adapter_invoice extends ArrayAdapter
<invoice_product_list> {
public custom_adapter_invoice(Context context,
ArrayList<invoice_product_list> product_details) {
super(context, R.layout.custom_row_invoice_item, product_details);
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
LayoutInflater layoutInflater = LayoutInflater.from(getContext());
View view =
layoutInflater.inflate(R.layout.custom_row_invoice_item,parent,false);
invoice_product_list products = getItem(position);
TextView txt_product_name =
(TextView)view.findViewById(R.id.txt_product_name);
TextView txt_product_price =
(TextView)view.findViewById(R.id.txt_product_price);
TextView txt_product_qty =
(TextView)view.findViewById(R.id.txt_product_qty);
TextView txt_product_code =
(TextView)view.findViewById(R.id.txt_product_code);
txt_product_name.setText(products.getProduct_name());
txt_product_price.setText(String.valueOf(products.getProduct_price()));
txt_product_qty.setText(String.valueOf(products.getProduct_qty()));
txt_product_code.setText(String.valueOf(products.getProduct_code()));
return view;
}
<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:context="com.tournonstop.m.invoicemanager.Create_invoice"
tools:showIn="@layout/activity_create_invoice">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:background="@android:color/darker_gray">
<include layout="@layout/toolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
<FrameLayout
android:layout_width="match_parent"
android:layout_height="85dp"
android:layout_marginTop="5dp"
android:layout_marginLeft="5dp"
android:layout_marginRight="5dp"
android:background="@android:color/white"
android:id="@+id/invoice_frame_company">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="@string/company_name"
android:id="@+id/txt_company_name"
android:layout_marginLeft="15dp"
android:layout_marginTop="15dp"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="@string/invoice_date"
android:id="@+id/txt_invoice_date"
android:layout_gravity="right"
android:layout_marginRight="15dp"
android:layout_marginTop="15dp"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="@string/invoice_no"
android:id="@+id/textView3"
android:layout_marginLeft="15dp"
android:layout_marginTop="45dp"/>
</FrameLayout>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="50dp"
android:layout_marginTop="5dp"
android:layout_marginLeft="5dp"
android:layout_marginRight="5dp"
android:background="@android:color/white"
android:id="@+id/invoice_frame_client"
android:clickable="true">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="@string/to"
android:id="@+id/txt_to"
android:layout_marginLeft="10dp"
android:layout_marginTop="10dp"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:id="@+id/txt_client_address"
android:layout_marginLeft="50dp"
android:layout_marginTop="10dp"
android:hint="@string/client_hint"/>
</FrameLayout>
----listview to add items-----
<FrameLayout
android:layout_width="match_parent"
android:layout_height="210dp"
android:layout_marginTop="5dp"
android:layout_marginLeft="5dp"
android:layout_marginRight="5dp"
android:background="@android:color/white"
android:id="@+id/invoice_frame_add_item"
android:clickable="true">
<ListView
android:layout_width="match_parent"
android:layout_height="150dp"
android:id="@+id/listview_additem"
android:divider="#040404" />
</FrameLayout>
<FrameLayout
android:layout_width="match_parent"
android:layout_height="40dp"
android:layout_marginTop="2dp"
android:layout_marginLeft="5dp"
android:layout_marginRight="5dp"
android:background="@android:color/white"
android:id="@+id/invoice_frame_sub_total">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="@string/total_label"
android:id="@+id/txt_sub_total_label"
android:layout_marginLeft="10dp"
android:layout_marginTop="10dp"
android:textStyle="bold"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="@string/total"
android:id="@+id/txt_sub_total"
android:layout_gravity="right"
android:layout_marginTop="10dp"
android:layout_marginRight="10dp"
android:textStyle="bold"
android:hint="@string/total_hint" />
</FrameLayout>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginTop="40dp"
android:text="@string/invoice_btn"
android:textStyle="bold"
android:background="@color/colorPrimaryDark"
android:textColor="@android:color/white"
android:clickable="true"
android:id="@+id/btn_invoice_save" />
</LinearLayout>
< /android.support.v4.widget.DrawerLayout>
package com.tournonstop.m.invoicemanager;
public class invoice_product_list {
private String product_name;
private double product_price;
private int product_qty;
private int product_code;
public invoice_product_list(){
}
public invoice_product_list(String product_name,double
product_price,int product_qty,int product_code){
this.product_name = product_name;
this.product_price = product_price;
this.product_qty = product_qty;
this.product_code = product_code;
}
public String getProduct_name() {
return product_name;
}
public void setProduct_name(String product_name) {
this.product_name = product_name;
}
public int getProduct_code() {
return product_code;
}
public void setProduct_code(int product_code) {
this.product_code = product_code;
}
public double getProduct_price() {
return product_price;
}
public void setProduct_price(double product_price) {
this.product_price = product_price;
}
public int getProduct_qty() {
return product_qty;
}
public void setProduct_qty(int product_qty) {
this.product_qty = product_qty;
}
}
答案 0 :(得分:0)
将项添加到您在适配器中使用的列表中(在验证适配器不为null之后)在适配器对象上调用方法notifyDataSetChanged()。
答案 1 :(得分:0)
create_invoice活动
//arraylist
ArrayList<invoice_product_list> productList = new ArrayList<>();
//customAdapter
customAdapterInvoice = new custom_adapter_invoice
(Create_invoice.this, productList);
customAdapterInvoice.addProduct(products)
自定义适配器
public class custom_adapter_invoice extends ArrayAdapter <invoice_product_list>
{
ArrayList<invoice_product_list> productList = new ArrayList<>();
public custom_adapter_invoice(Context context,
ArrayList<invoice_product_list> product_details) {
super(context, R.layout.custom_row_invoice_item, product_details);
this.productList =product_details
}
public void addProduct(Product products
productList.add(products);
notifyDataSetChanged();
}
......
}
答案 2 :(得分:0)
不,它没有改变任何东西。如果你想要最新的工作方法,那么我更喜欢RecyclerView自定义列表适配器。这个链接非常适合recyclerview