Question

在OnCreate我有这个productsku，我想在完成后删除存储的数据，preferences.edit().remove("Productsku").commit();我把它们放在正确的位置？当我做了与内容相关的事情时，我检查了LogCat，它仍然让我进入＆＃34; if (productsku != null)＆＃34;

public class ProductActivity extends FragmentActivity implements
    OnFocusChangeListener, OnClickListener, NumberPickerDialogListener,
    AddedToCartDialogListener {
@Override
public void onCreate(Bundle savedInstanceState) {
    Log.d(getClass().getSimpleName(), "onCreate");

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_product);

    SharedPreferences preferences1 = PreferenceManager.getDefaultSharedPreferences(this);
    content=preferences1.getString("Content", "");

    SharedPreferences preferences = getSharedPreferences("myPref",MODE_PRIVATE);
    productsku=preferences.getString("Productsku", "");
    Log.d("Productsku",productsku.toString());
    if(productsku !=null)
    {
        Log.d("StartProductsku","OK");
        new GetProductDetailsTask2().execute();
        preferences.edit().remove("Productsku").commit();
        Log.d("EndProductsku","OK");
    }
    else
    {
        if(content !=null)
        {
            Log.d("StartContent","OK");
            new GetProductDetailsTask1().execute();
            preferences1.edit().remove("Content").commit();
        }

private class GetProductDetailsTask2 extends AsyncTask<String, String, Void> {
    @Override
    protected void onPreExecute() {
        layoutProgress.setVisibility(View.VISIBLE);
    };

    @Override
    protected Void doInBackground(String... params) {
        if(productsku ==null)
        {
            Log.d("Productsku","inside");
            product = Product.getSelected();
            product.setId(productsku);
            JSONService.updateProductDetails(product);
        }
        else 
        {
            product=JSONService.getProductDetails(productsku);

        }

        return null;
    }

    @Override
    protected void onPostExecute(Void result) {
        updateUI();
        layoutProgress.setVisibility(View.GONE);
        shortDescription.setVisibility(View.VISIBLE);
        description.setVisibility(View.VISIBLE);
    }
}

Answer 1

你的问题在这里：

SharedPreferences preferences = getSharedPreferences("myPref",MODE_PRIVATE);
productsku=preferences.getString("Productsku", "");

getString中的第二个参数是默认值（如果未找到首选项，则返回值）。尝试执行以下操作：

 productsku=preferences.getString("Productsku", "");
Log.d("Productsku",productsku.toString());
if(!productsku.equals(""))
{
    Log.d("StartProductsku","OK");
    new GetProductDetailsTask2().execute();
    preferences.edit().remove("Productsku").commit();
    Log.d("EndProductsku","OK");
}

希望有所帮助

删除共享首选项数据

1 个答案: