android中片段的数据传递问题适配器（返回默认值<null>）

Question

我试图通过 intent 和 bundle 从一个活动**（实际上是活动的适配器）** 传递一些数据到片段。所有字符串值都可以毫无问题地传递给片段，但整数和双精度值都作为 null 传递。

显示此警告：

键 invoiceId 应为字符串，但值为 java.lang.Integer。这 返回默认值

尝试转换生成的内部异常：

java.lang.ClassCastException: java.lang.Integer 无法转换为 java.lang.String

代码如下：

Intent intent = new Intent(mContext, SalesViewActivity.class);

                intent.putExtra(SalesViewFragment.ARG_INVOICE_ID, sales.get(position).getInvoiceInvoiceId());
                intent.putExtra(SalesViewFragment.ARG_INVOICE_CODE, sales.get(position).getInvoiceInvoiceCode());
                intent.putExtra(SalesViewFragment.ARG_CUSTOMER_ID, sales.get(position).getInvoiceCustomerId());
                intent.putExtra(SalesViewFragment.ARG_INVOICE_ORDER_ID, sales.get(position).getInvoiceOrderId());

                intent.putExtra(SalesViewFragment.ARG_SALES_PERSON, sales.get(position).getInvoiceSalesPerson());
                intent.putExtra(SalesViewFragment.ARG_INVOICE_CUSTOMER_NAME, sales.get(position).getCustomerCustomerName());

                intent.putExtra(SalesViewFragment.ARG_INVOICE_TOTAL, sales.get(position).getInvoiceTotalAmount());
                intent.putExtra(SalesViewFragment.ARG_START_TIME, sales.get(position).getInvoiceStartTimestamp());

                intent.putExtra(SalesViewFragment.ARG_INVOICE_DISCOUNT, sales.get(position).getInvoiceDiscountTotal());
                intent.putExtra(SalesViewFragment.ARG_INVOICE_CASH_DISCOUNT, sales.get(position).getInvoiceCashDiscount());
                intent.putExtra(SalesViewFragment.ARG_INVOICE_DISCOUNT_TRADE, sales.get(position).getInvoiceDiscountTrade());
                intent.putExtra(SalesViewFragment.ARG_INVOICE_DISCOUNT_PARENTAGE, sales.get(position).getInvoiceDiscountParentage());

                intent.putExtra(SalesViewFragment.ARG_INVOICE_STATUS, sales.get(position).getInvoiceStatus());
                intent.putExtra(SalesViewFragment.ARG_INVOICE_REMARKS, sales.get(position).getInvoiceRemarks());

                mContext.startActivity(intent);

这里是SalesViewActivity.java （我认为问题出现在这里）

Fragment mFragment = null;
        mFragment = new SalesViewFragment();

        Bundle bundle = new Bundle();

        bundle.putString(SalesViewFragment.ARG_INVOICE_ID, getIntent().getStringExtra(SalesViewFragment.ARG_INVOICE_ID));
        bundle.putString(SalesViewFragment.ARG_INVOICE_CODE, getIntent().getStringExtra(SalesViewFragment.ARG_INVOICE_CODE));
        bundle.putString(SalesViewFragment.ARG_CUSTOMER_ID, getIntent().getStringExtra(SalesViewFragment.ARG_CUSTOMER_ID));
        bundle.putString(SalesViewFragment.ARG_INVOICE_ORDER_ID, getIntent().getStringExtra(SalesViewFragment.ARG_INVOICE_ORDER_ID));

        bundle.putString(SalesViewFragment.ARG_SALES_PERSON, getIntent().getStringExtra(SalesViewFragment.ARG_SALES_PERSON));
        bundle.putString(SalesViewFragment.ARG_INVOICE_CUSTOMER_NAME, getIntent().getStringExtra(SalesViewFragment.ARG_INVOICE_CUSTOMER_NAME));

        bundle.putString(SalesViewFragment.ARG_INVOICE_TOTAL, getIntent().getStringExtra(SalesViewFragment.ARG_INVOICE_TOTAL));
        bundle.putString(SalesViewFragment.ARG_START_TIME, getIntent().getStringExtra(SalesViewFragment.ARG_START_TIME));

        bundle.putString(SalesViewFragment.ARG_INVOICE_DISCOUNT, getIntent().getStringExtra(SalesViewFragment.ARG_INVOICE_DISCOUNT));
        bundle.putString(SalesViewFragment.ARG_INVOICE_CASH_DISCOUNT, getIntent().getStringExtra(SalesViewFragment.ARG_INVOICE_CASH_DISCOUNT));
        bundle.putString(SalesViewFragment.ARG_INVOICE_DISCOUNT_TRADE, getIntent().getStringExtra(SalesViewFragment.ARG_INVOICE_DISCOUNT_TRADE));
        bundle.putString(SalesViewFragment.ARG_INVOICE_DISCOUNT_PARENTAGE, getIntent().getStringExtra(SalesViewFragment.ARG_INVOICE_DISCOUNT_PARENTAGE));

        bundle.putString(SalesViewFragment.ARG_INVOICE_STATUS, getIntent().getStringExtra(SalesViewFragment.ARG_INVOICE_STATUS));
        bundle.putString(SalesViewFragment.ARG_INVOICE_REMARKS, getIntent().getStringExtra(SalesViewFragment.ARG_INVOICE_REMARKS));

        mFragment.setArguments(bundle);

        FragmentManager fragmentManager = getSupportFragmentManager();
        fragmentManager.beginTransaction()
                .replace(R.id.frameLayout, mFragment).commit();

这里是 salesViewFragment.java

public static final String ARG_INVOICE_ID = "invoiceId";
    public static final String ARG_INVOICE_CODE = "code";
    public static final String ARG_CUSTOMER_ID = "customerId";
    public static final String ARG_INVOICE_ORDER_ID = "orderId";

    public static final String ARG_SALES_PERSON = "salesPerson";
    public static final String ARG_INVOICE_CUSTOMER_NAME = "customerName";

    public static final String ARG_INVOICE_TOTAL = "total";
    public static final String ARG_START_TIME = "startTime";

    public static final String ARG_INVOICE_DISCOUNT = "discount";
    public static final String ARG_INVOICE_CASH_DISCOUNT = "discountCash";
    public static final String ARG_INVOICE_DISCOUNT_TRADE = "discountTrade";
    public static final String ARG_INVOICE_DISCOUNT_PARENTAGE = "discountPerce";

    public static final String ARG_INVOICE_STATUS = "invoiceStatus";
    public static final String ARG_INVOICE_REMARKS = "invoiceRemarks";

将数据获取到片段后，我会将它们分配给变量。 这是代码：

 @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        if (getArguments().containsKey(ARG_INVOICE_ID)) {

            invoiceID = getArguments().getInt(ARG_INVOICE_ID);
            code = getArguments().getString(ARG_INVOICE_CODE);
            cusID = getArguments().getInt(ARG_CUSTOMER_ID);
            orderId = getArguments().getInt(ARG_INVOICE_ORDER_ID);

            salesPerson = getArguments().getString(ARG_SALES_PERSON);
            cusName = getArguments().getString(ARG_INVOICE_CUSTOMER_NAME);

            total = getArguments().getDouble(ARG_INVOICE_TOTAL);
            startTime = getArguments().getString(ARG_START_TIME);

            discounts = getArguments().getDouble(ARG_INVOICE_DISCOUNT);
            discoutCash = getArguments().getDouble(ARG_INVOICE_CASH_DISCOUNT);
            discoutTrade = getArguments().getDouble(ARG_INVOICE_DISCOUNT_TRADE);
            discoutParcent = getArguments().getDouble(ARG_INVOICE_DISCOUNT_PARENTAGE);

            invoiceStatus = getArguments().getString(ARG_INVOICE_STATUS);
            invoiceRemarks = getArguments().getString(ARG_INVOICE_REMARKS);
        }
    }

我尝试了很多解决方案并阅读了一些文章，但对我不起作用。如果我做错了什么，请帮助我找到它。任何解决方案高度赞赏。提前致谢。

以下是一些参考资料：

why getStringExtra doesn't give the proper output?

Key _id expected Parcelable but value was java.lang.Long. while passing Parceable object between Activity https://github.com/fechanique/cordova-plugin-fcm/issues/253

Answer 1

在你开始SalesViewActivity的课堂上，你使用

intent.putExtra(SalesViewFragment.ARG_INVOICE_ID, sales.get(position).getInvoiceInvoiceId());

sales.get(position).getInvoiceInvoiceId() 的类型是 Integer，但您使用的是 SalesViewActivity

bundle.putString(SalesViewFragment.ARG_INVOICE_ID, getIntent().getStringExtra(SalesViewFragment.ARG_INVOICE_ID));

您将Integer 转换为String，这就是应用程序抛出ClassCastException 的原因。

在SalesViewActivity 中更改您的代码

bundle.putInt(SalesViewFragment.ARG_INVOICE_ID, getIntent().getIntExtra(SalesViewFragment.ARG_INVOICE_ID, 0));

而不是

bundle.putString(SalesViewFragment.ARG_INVOICE_ID, getIntent().getStringExtra(SalesViewFragment.ARG_INVOICE_ID));

对于使用 getIntent().getDoubleExtra() 而不是 getIntent().getStringExtra() 的双精度值。

Answer 2

我在使用 Bundle 对象传递数据时遇到了类似的问题。就我而言，我定义了 2 个键，例如：

    public static final String ARGS_OPTIONS = "com.example.modalMenu.args.options";
    public static final String ARGS_ICONS = "com.example.modalMenu.args.options";

问题是因为我从 IDE 中的 ARGS_OPTIONS 复制并粘贴了 ARGS_ICONS，导致使用 ARGS_ICONS 内容覆盖 ARGS_OPTIONS，因为键字符串都相同。然后我更改了 ARGS_ICONS 字符串并繁荣！它是固定的：

    public static final String ARGS_OPTIONS = "com.example.modalMenu.args.options";
    public static final String ARGS_ICONS = "com.example.modalMenu.args.icons";

结论：复制粘贴是一种甜毒，就像糖对我们的身体一样。小心使用它，以免污染您的代码。