微调监听器LiveData问题

本文介绍了微调监听器LiveData问题的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

在我的片段中，我有两个微调工具。

两者都由在ViewModel中观察到的LiveData填充，如下所示：

数据-lang="js"数据-隐藏="假"数据-控制台="真"数据-巴贝尔="假">

      // Observe Filtered ProductGroups and populate Spinner
        businessViewModel.filteredAppDataProductGroups.observe(viewLifecycleOwner, { productGroupArrayList ->
            if (!productGroupArrayList.isNullOrEmpty()){
                val adapter = ArrayAdapter(requireContext(), android.R.layout.simple_spinner_dropdown_item, productGroupArrayList)
                binding.inventoryAddEditProductGroupSpinner.adapter = adapter
            }
        })


// Observe Filtered ProductTypes and populate Spinner
        businessViewModel.filteredAppDataProductTypes.observe(viewLifecycleOwner, { productTypeArrayList ->
            if (productTypeArrayList != null){
                val adapter = ArrayAdapter(requireContext(), android.R.layout.simple_spinner_dropdown_item, productTypeArrayList)
                binding.inventoryAddEditProductTypeSpinner.adapter = adapter
            }
        })

binding.inventoryAddEditProductGroupSpinner.onItemSelectedListener = object: AdapterView.OnItemSelectedListener{ override fun onItemSelected(parent:AdapterView<*>, view: View, position: Int, id: Long){ val productGroupObject = parent.selectedItem as ProductGroupObject if (productGroupObject.productGroupID.isNotEmpty()){ businessViewModel.updateCurrentProductGroupVMLiveData(productGroupObject.productGroupID) } } override fun onNothingSelected(parent: AdapterView<*>){ } }

fun updateCurrentProductGroupVMLiveData (currentProductGroupId: String) { val newProductGroup = allAppDataProductGroups.value?.find { productGroup -> productGroup.productGroupID == currentProductGroupId } _currentProductGroup.value = newProductGroup if(newProductGroup?.productGroup != null) { val filteredProductsList = allAppDataProductTypes.value?.filter { productTypeObject -> productTypeObject.productGroup == newProductGroup.productGroup} as ArrayList<ProductTypeObject> _filteredAppDataProductTypes.value = filteredProductsList } Log.d(TAG, "updateCurrentProductGroupVMLiveData(): '_currentProductGroupId.value' updated ($currentProductGroupId)") }

--------- beginning of crash 2021-10-06 23:06:34.740 17510-17510/com.xxxxx.acorn E/AndroidRuntime: FATAL EXCEPTION: main Process: com.locators.acorn, PID: 17510 java.lang.NullPointerException: Parameter specified as non-null is null: method kotlin.jvm.internal.Intrinsics.checkNotNullParameter, parameter view at com.xxxxx.acorn.business.inventory.InventoryAddEditFragment$setSpinnerListeners$2.onItemSelected(InventoryAddEditFragment.kt) at android.widget.AdapterView.fireOnSelected(AdapterView.java:931) at android.widget.AdapterView.dispatchOnItemSelected(AdapterView.java:920) at android.widget.AdapterView.-wrap1(AdapterView.java) at android.widget.AdapterView$SelectionNotifier.run(AdapterView.java:890) at android.os.Handler.handleCallback(Handler.java:751) at android.os.Handler.dispatchMessage(Handler.java:95) at android.os.Looper.loop(Looper.java:154) at android.app.ActivityThread.main(ActivityThread.java:6077) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:866) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:756)

微调

微调监听器LiveData问题

问题描述

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