Question

我是Android编程新手。我正在实现扫描特定库存项目的功能，并搜索条形码（如果它已存在于ArrayList中）。如果它存在，那么我用InvnetoryFound片段替换当前的Scan片段，其中我可以选择更新数量并从ArrayList中完全删除项目。

我面临的问题是，当我再次扫描不同的库存条形码时删除库存后，扫描成功后，它显示的InventoryFound片段包含从ArrayList中删除的旧数据。以下是我的代码：

测试ArrayList代码：

public static String[] inve = new String[5];
public static ArrayList<String[]> inventory_list = new ArrayList<String[]>();

    inve[0] = "INV45879";
    inve[1] = "Bridge Support Pipe";
    inve[2] = "Pre-insulated pipe supports provide both support and insulation in hot and cold piping applications.Pre-insulated pipe supports provide both support and insulation in hot and cold piping applications.";
    inve[3] = "0885370720679";
    inve[4] = "2";

    inventory_list.add(inve);

    inve = new String[5];

    inve[0] = "INV45880";
    inve[1] = "Cement";
    inve[2] = "Pre-insulated pipe supports provide both support and insulation in hot and cold piping applications";
    inve[3] = "9771234567003";
    inve[4] = "8";

    inventory_list.add(inve);

如果扫描成功，则调用以下函数来替换片段：

private static void showFragment(Fragment fragment, String back_option) {

    try {
        // start transition
        FragmentTransaction ft = activity.getFragmentManager().beginTransaction();

        //if fragment Inventory is found then pass data to fragment
        if(back_option.equals("inventoryFound")){

             //sends found inventory list data to fragment

             String[] inv_data = inventory_list.get(inventory_index);
             Bundle bundle = new Bundle();
             bundle.putStringArray("inventory_data",inv_data);
             bundle.putInt("inventory_index",inventory_index);
             inventoryFoundFragment.setArguments(bundle);

             back_option = "null";


        // replace fragment
        if (!back_option.equals("null"))  // with back option
            ft.replace(R.id.frag_content, fragment).addToBackStack(back_option);
        else    // no back option
            ft.replace(R.id.frag_content, fragment);

        // commit
        ft.commit();
    }
    catch(Exception e){
        out("PROBLEM SHOWING FRAGMENT!!!"+e.getMessage());
    }
}

InventoryFound片段填充数据并正常工作。下面是我点击删除已填充库存时的代码：

public void removeInventory(){
    Shared.inventory_list.remove(inventory_index);
    Toast.makeText(mContext,"Inventory "+inventory_index+" Removed Successfully!", Toast.LENGTH_SHORT).show();

    FragmentTransaction ft = getActivity().getFragmentManager().beginTransaction();
    ft.remove(this);
    ft.replace(R.id.frag_content, new ScanFragment());
    ft.commit();
}

它已成功删除，但是当我再次扫描时，例如条形码＆＃34; 0885370720679＆＃34;它显示了InventoryFound片段上的先前数据。我在Logcat（Log.d）中调试了它，我能够看到正确的数据，但它没有显示在片段中。

任何建议或指导将不胜感激。

Answer 1

我找到了解决这个问题的方法。

当Fragment位于前台时，它会调用onResume（）方法。在这个方法中，我调用用户定义的函数，它重新设置Fragment字段的数据。我不知道解决这个问题是否正确，但它现在正在为我工作！

片段显示旧数据

1 个答案: