问题
in my application Listview is populated with data from Sqlite database. i use button to delete the items. And also modify the table in Sqlite Db .
SQL DB Class
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_table);
tv = (TextView) findViewById(R.id.txt_rates);
// checkout = (Button) findViewById(R.id.submit_btn);
ListCart = (ListView) findViewById(R.id.list_item);
pDialog = new ProgressDialog(this);
ctx = this;
CartData = Table.this.openOrCreateDatabase("SHOPPING_CART", MODE_PRIVATE, null);
CartData.execSQL("CREATE TABLE IF NOT EXISTS cart_items(product_id varchar, name varchar, price varchar, quantity integer, model varchar, image varchar, manufacturer varchar )");
ArrayList<CartProducts> myList = new ArrayList<CartProducts>();
Cursor crsr = CartData.rawQuery("SELECT * FROM cart_items", null);
final String[] productID = new String[crsr.getCount()];
final String[] ProductName = new String[crsr.getCount()];
final String[] ProductPrice = new String[crsr.getCount()];
final String[] ProductQuantity = new String[crsr.getCount()];
final String[] ProductModel = new String[crsr.getCount()];
final String[] ProductImage = new String[crsr.getCount()];
final String[] ProductManufacturer = new String[crsr.getCount()];
int j = 0;
while (crsr.moveToNext()) {
String id = crsr.getString(crsr.getColumnIndex("product_id"));
productID[j] = id;//product_id,name,price,quantity,model,image,manufacturer
name = crsr.getString(crsr.getColumnIndex("name"));
ProductName[j] = name;
String price = crsr.getString(crsr.getColumnIndex("price"));
ProductPrice[j] = price;
String s = ProductPrice[j].toString();
s = s.replace(",", "");
String[] parts = s.split("\\."); // escape .
String part1 = parts[0];
String part2 = parts[1];
part1 = part1.replace("₹", "");
total = Integer.parseInt(part1); // Toast.makeText(Table.this, part1, Toast.LENGTH_SHORT).show();
String qnty = crsr.getString(crsr.getColumnIndex("quantity"));
ProductQuantity[j] = qnty;
String s2 = ProductQuantity[j].toString();
total1 = Integer.parseInt(s2);
sum = total * total1;
String model = crsr.getString(crsr.getColumnIndex("model"));
ProductModel[j] = model;
String image = crsr.getString(crsr.getColumnIndex("image"));
ProductImage[j] = image;
String manufacturer = crsr.getString(crsr.getColumnIndex("manufacturer"));
ProductManufacturer[j] = manufacturer;
//Toast.makeText(getApplicationContext(),productID[j]+""+ProductName[j]+""+ProductPrice[j]+""+ProductQuantity[j]+""+ProductModel[j]+""+ProductImage[j]+""+ProductManufacturer[j] , Toast.LENGTH_SHORT).show();
myList.add(new CartProducts(productID[j], ProductName[j], ProductPrice[j], ProductQuantity[j], ProductModel[j], ProductImage[j], ProductManufacturer[j]));
j++;
gtot = gtot + sum;
}
ListCart.setAdapter(new CartProduct_ListAdapter(ctx, R.layout.activity_cart_row, myList));
tv.setText("Rs. " + String.valueOf(gtot));
String s1 = ProductPrice.toString();
/*Delete Query*/
/* db.execSQL("DELETE FROM cart_items WHERE product_id='"+editRollno.getText()+"'"); */
/* checkout.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent i = new Intent(getApplicationContext(), Product_details.class);
startActivity(i);
}
}); */
}
Adapter class
public class CartProduct_ListAdapter extends ArrayAdapter<CartProducts> {
Bitmap bitmap;
ImageView img;
String urll;
SQLiteDatabase CartData;
SQLiteOpenHelper dbhelper;
Integer total = 0, quanty = 1, grandtot = 0, fulltotal = 0, i = 0, sum;
int it;
private int resource;
private LayoutInflater inflater;
private Context context;
public CartProduct_ListAdapter(Context ctx, int resourceId, List<CartProducts> objects) {
super(ctx, resourceId, objects);
resource = resourceId;
inflater = LayoutInflater.from(ctx);
context = ctx;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
/* create a new view of my layout and inflate it in the row */
convertView = (RelativeLayout) inflater.inflate(resource, null);
final CartProducts banqt = getItem(position);
TextView txtprice = (TextView) convertView.findViewById(R.id.txt_item_price);
txtprice.setText(banqt.getPrice());
String s = txtprice.getText().toString();
s = s.replace(",", "");
String[] parts = s.split("\\."); // escape .
String part1 = parts[0];
String part2 = parts[1];
part1 = part1.replace("₹", "");// Toast.makeText(getContext(), part1, Toast.LENGTH_LONG).show();
total = Integer.parseInt(part1);
EditText editqu = (EditText) convertView.findViewById(R.id.edt_qn);
editqu.setText(banqt.getQuantity());
quanty = Integer.parseInt(editqu.getText().toString());
grandtot = total * quanty;
TextView total = (TextView) convertView.findViewById(R.id.txt_total);
total.setText(String.valueOf(grandtot));
Button delet = (Button) convertView.findViewById(R.id.btn_remove);
delet.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
/*delete function*/
it = Integer.parseInt(banqt.getProduct_id());
Log.e("***i value******", String.valueOf(it)); //Toast.makeText(getContext(), String.valueOf(it), Toast.LENGTH_LONG).show();
CartData.delete("cart_items", "product_id='" + it + "'", null);
CartData.close();
}
});
TextView txtName = (TextView) convertView.findViewById(R.id.product_name);
txtName.setText(banqt.getName());
img = (ImageView) convertView.findViewById(R.id.img_product);
urll = banqt.getImage().toString();
urll = urll.replaceAll(" ", "%20");// Toast.makeText(getContext(),urll,Toast.LENGTH_LONG).show();
new LoadImage().execute(urll);
return convertView;
}
private class LoadImage extends AsyncTask<String, String, Bitmap> {
@Override
protected void onPreExecute() {
super.onPreExecute();
}
protected Bitmap doInBackground(String... args) {
try {
bitmap = BitmapFactory.decodeStream((InputStream) new URL(args[0]).getContent());
} catch (Exception e) {
e.printStackTrace();
}
return bitmap;
}
protected void onPostExecute(Bitmap image) {
if (image != null) {
img.setImageBitmap(image);
// pDialog.dismiss();
} else {
// pDialog.dismiss();
Toast.makeText(getContext(), "Image Does Not exist or Network Error", Toast.LENGTH_SHORT).show();
}
}
}
}
And layout im using CardView And im inflate CardView on my layout
XML CardView code
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.v7.widget.CardView
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="290dp"
android:id="@+id/cv"
android:layout_marginTop="10dp"
android:layout_marginLeft="10dp"
android:layout_marginRight="10dp"
card_view:cardCornerRadius="0dp"
card_view:cardBackgroundColor="#FFFFFF">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/r1">
<ImageView
android:layout_width="80dp"
android:layout_height="80dp"
android:id="@+id/img_product"
android:layout_centerHorizontal="true" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/product_name"
android:layout_below="@id/img_product"
android:textSize="18dp"
android:text="Parvana Fancy Necklace Set"
android:layout_marginTop="25dp"
android:textStyle="bold"
android:inputType="textMultiLine"
android:layout_centerHorizontal="true" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/txt_item_price"
android:text="12000 INR"
android:textStyle="bold"
android:textSize="15dp"
android:gravity="center"
android:layout_alignTop="@+id/edt_qn"
android:layout_below="@id/product_name"
android:layout_marginLeft="25dp"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/txt_availability"
android:text="x"
android:textStyle="bold"
android:textSize="16dp"
android:layout_alignTop="@+id/txt_item_price"
android:layout_toRightOf="@+id/txt_item_price"
android:layout_toEndOf="@+id/txt_item_price"
android:layout_marginLeft="10dp"
android:layout_marginStart="54dp" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/edt_qn"
android:textSize="16dp"
android:layout_toRightOf="@id/txt_availability"
android:layout_below="@id/product_name"
android:layout_marginTop="18dp"
android:layout_marginLeft="10dp"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/txt_eql"
android:text="="
android:layout_toRightOf="@id/edt_qn"
android:layout_below="@id/product_name"
android:layout_marginTop="22dp"
android:layout_marginLeft="10dp"
android:textStyle="bold"
android:textSize="16dp"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/txt_total"
android:text="RS.234"
android:layout_toRightOf="@id/txt_eql"
android:layout_below="@id/product_name"
android:layout_marginTop="25dp"
android:layout_marginLeft="10dp"
android:textStyle="bold"
android:textSize="15dp"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/btn_remove"
android:text=" Delete"
android:textSize="13dp"
android:drawableLeft="@drawable/delete_icon"
android:layout_alignParentBottom="true"
android:layout_alignLeft="@+id/txt_availability"
android:layout_alignStart="@+id/txt_availability" />
</RelativeLayout>
</android.support.v7.widget.CardView>
回答1:
this is what i have done to delete list row try something like this in your adapter class
delet.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
cartdata.updateSelected(Integer.parseInt(cart_pdiscription[i]), 0);
cartdata.deleteProduct(Integer.parseInt(cart_pdiscription[i]));
Intent intent = ((CartList) context).getIntent();
((CartList) context).finish();
context.startActivity(intent);
}
});
来源：https://stackoverflow.com/questions/32919600/in-android-how-delete-data-from-listview-by-button-click