android - 无法访问 PopupWindow 布局中的资源，对象引用为空

Question

我有一个 android 应用程序，当从侧边栏单击一个选项时，它会转到一个 fragment ，然后进入另一个具有可点击单选按钮的 fragment 。当点击这些时，它会创建一个弹出窗口，其中包含一些文本字段。

基本上流程是这样的，

Activity --> fragment 1 --> fragment 2 --> 弹出窗口

当我尝试访问此弹出窗口中的资源时，例如:

damageComponenetAutoCompleteTextview = (AutoCompleteTextView) findViewById(R.id.popup_damage_component_item);
damageComponenetAutoCompleteTextview.requestFocus();

在 damageComponenetAutoCompleteTextview.requestFocus(); 行中它给我一个错误，

尝试在空对象引用上调用虚方法

我认为这是由于我在调用资源时所指的错误观点所致。希望有人能指出我做错了什么。提前致谢。

这是我用来创建弹出窗口的方法。

public void showDamagedItemEntryPopup(RadioButton radioButton, View view){

    LayoutInflater layoutInflater = (LayoutInflater)getBaseContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    ViewGroup viewG = ((ViewGroup)view.findViewById(R.id.damaged_comp_popup));

    //I tried passing the root view to inflate() method instead of passing it null. Didn't work.
    //View popupView = layoutInflater.inflate(R.layout.component_selection_popup, null);

    View popupView = layoutInflater.inflate(R.layout.component_selection_popup, null);

    final PopupWindow popupWindow = new PopupWindow(
            popupView,
            ViewGroup.LayoutParams.WRAP_CONTENT,
            ViewGroup.LayoutParams.WRAP_CONTENT);

    popupWindow.setAnimationStyle(R.style.popupAnimation);

    //I tried setting the content view manually but didnt work        
    //popupWindow.setContentView(view.findViewById(R.id.damaged_comp_popup));

    Button buttonClose = (Button)popupView.findViewById(R.id.close_add_component_btn);

    // Close button damaged item popop window
    buttonClose.setOnClickListener(new Button.OnClickListener(){

        @Override
        public void onClick(View v) {
            popupWindow.dismiss();
        }
    });


    originalAmount = (EditText)this.findViewById(R.id.popup_add_component_original_amount);
    customerContribution = (EditText)this.findViewById(R.id.popup_percentage);
    quantity = (EditText)this.findViewById(R.id.popup_quantity);
    finalAmount = (EditText)this.findViewById(R.id.popup_add_component_final_amount);
    remarks = (EditText)this.findViewById(R.id.popup_add_component_remarks);

    // Item Spinner
    itemSpinnerArray = new ArrayList<String>();
    itemSpinnerArray.add("Select Item");

    // Status Spinner
    ArrayList<String> statusSpinnerArray = new ArrayList<String>();
    statusSpinnerArray.add("MR");
    statusSpinnerArray.add("DR");
    statusSpinnerArray.add("SP");

    // Error comes at this point initially. When these Resource access line codes are commented, the popup works fine.

    damageComponenetAutoCompleteTextview = (AutoCompleteTextView) findViewById(R.id.popup_damage_component_item);
    damageComponenetAutoCompleteTextview.requestFocus();
    ArrayAdapter<String> itemSpinnerArrayAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_dropdown_item, itemSpinnerArray);
    damageComponenetAutoCompleteTextview.setThreshold(1);
    damageComponenetAutoCompleteTextview.setAdapter(itemSpinnerArrayAdapter);

    damageComponenetAutoCompleteTextview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            //int index = cityNames.indexOf(actvCity.getText().toString());
            itemSpinnerValue = (String) parent.getItemAtPosition(position);
            Log.d("SK-->", "----------------------------------------------------------");
            Log.d("SK-->","itemSpinnerValue: " + itemSpinnerValue);
        }
    });

    statusSpinner = (Spinner)this.findViewById(R.id.popup_status_spinner);
    ArrayAdapter<String> statusSpinnerArrayAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_dropdown_item, statusSpinnerArray);
    statusSpinner.setAdapter(statusSpinnerArrayAdapter);

    //Creating a text Watcher
    TextWatcher textWatcher = new TextWatcher() {

        @Override
        public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {

        }

        @Override
        public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {

        }

        @Override
        public void afterTextChanged(Editable editable) {
            //here, after we introduced something in the EditText we get the string from it
            //String answerString = originalAmount.getText().toString();

            if (originalAmount.getText().toString().trim().equals("") || customerContribution.getText().toString().trim().equals("")
                    || quantity.getText().toString().trim().equals("")) {

                // Error , one or more editText are empty

            }
            else
            {
                calculateFinalAmount();
            }

            //and now we make a Toast
            //modify "yourActivity.this" with your activity name .this
            //Toast.makeText(yourActivity.this,"The string from EditText is: "+answerString,0).show();

        }
    };

    // Adding Text Watcher to our text boxes
    originalAmount.addTextChangedListener(textWatcher);
    customerContribution.addTextChangedListener(textWatcher);
    quantity.addTextChangedListener(textWatcher);

    // Show the popup
    popupWindow.showAtLocation(view, Gravity.CENTER, 0, 0);

}

这是我用于弹出窗口的 XML。

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/damaged_comp_popup"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="@color/popup_wire">

<LinearLayout
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:orientation="vertical"
    android:layout_margin="2dp"
    android:background="@color/popup_background">

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical">

        <AutoCompleteTextView
            android:id="@+id/popup_damage_component_item"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_centerHorizontal="true"
            android:layout_alignParentTop="true"
            android:layout_alignParentLeft="true"
            android:layout_alignParentRight="true"
            android:layout_marginLeft="10dp"
            android:layout_marginRight="10dp"
            android:layout_marginTop="20dp"
            android:layout_marginBottom="5dp"
            android:hint="@string/damaged_componenet_item_string"/>

        <Spinner
            android:id="@+id/popup_status_spinner"
            android:layout_width="122dp"
            android:layout_height="wrap_content"
            android:layout_alignParentLeft="true"
            android:layout_below="@+id/popup_damage_component_item"
            android:layout_marginLeft="10dp"
            android:layout_marginTop="0dp"
            android:layout_marginBottom="5dp"
            android:layout_marginRight="5dp" />

        <EditText
            android:id="@+id/popup_add_component_original_amount"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@+id/popup_damage_component_item"
            android:layout_alignParentRight="true"
            android:layout_marginBottom="5dp"
            android:layout_marginLeft="5dp"
            android:layout_marginRight="10dp"
            android:layout_marginTop="22dp"
            android:layout_toRightOf="@+id/popup_status_spinner"
            android:ems="10"
            android:hint="@string/original_amount_string"
            android:inputType="number" />

        <EditText
            android:id="@+id/popup_percentage"
            android:layout_width="52dp"
            android:layout_height="wrap_content"
            android:layout_alignParentLeft="true"
            android:layout_below="@+id/popup_status_spinner"
            android:layout_marginBottom="5dp"
            android:layout_marginLeft="10dp"
            android:layout_marginRight="2dp"
            android:layout_marginTop="22dp"
            android:ems="10"
            android:hint="@string/percentage_string"
            android:inputType="number" />

        <TextView
            android:id="@+id/popup_percentageMark"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignBottom="@+id/popup_percentage"
            android:layout_toRightOf="@+id/popup_percentage"
            android:text="@string/percentage_string"
            android:textAppearance="?android:attr/textAppearanceMedium"
            android:layout_marginLeft="1dp"
            android:layout_marginRight="0dp"
            android:layout_marginTop="5dp"
            android:layout_marginBottom="5dp" />

        <EditText
            android:id="@+id/popup_quantity"
            android:layout_width="46dp"
            android:layout_height="wrap_content"
            android:layout_alignBaseline="@+id/popup_percentage"
            android:layout_alignBottom="@+id/popup_percentage"
            android:layout_marginBottom="5dp"
            android:layout_marginLeft="5dp"
            android:layout_marginRight="6dp"
            android:layout_marginTop="5dp"
            android:layout_toRightOf="@+id/popup_percentageMark"
            android:ems="10"
            android:hint="@string/quantity_string"
            android:inputType="number" />

        <EditText
            android:id="@+id/popup_add_component_final_amount"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignBaseline="@+id/popup_quantity"
            android:layout_alignBottom="@+id/popup_quantity"
            android:layout_marginBottom="5dp"
            android:layout_marginLeft="5dp"
            android:layout_marginRight="10dp"
            android:layout_alignParentRight="true"
            android:layout_marginTop="5dp"
            android:layout_toRightOf="@+id/popup_quantity"
            android:ems="10"
            android:hint="@string/final_amount_string"
            android:inputType="number" />

        <EditText
            android:id="@+id/popup_add_component_remarks"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentLeft="true"
            android:layout_alignParentRight="true"
            android:layout_below="@+id/popup_percentage"
            android:layout_marginBottom="10dp"
            android:layout_marginLeft="10dp"
            android:layout_marginRight="10dp"
            android:layout_marginTop="22dp"
            android:ems="10"
            android:hint="@string/remarks_string"
            android:inputType="text|textMultiLine" />

        <Button
            android:id="@+id/add_component_btn"
            android:layout_width="50dp"
            android:layout_height="wrap_content"
            android:layout_marginLeft="200dp"
            android:layout_below="@+id/popup_add_component_remarks"
            android:background="@drawable/correct"
            android:layout_marginBottom="15dp"
            android:onClick="onSaveItem"/>

        <Button
            android:id="@+id/close_add_component_btn"
            android:layout_width="50dp"
            android:layout_height="wrap_content"
            android:layout_below="@+id/popup_add_component_remarks"
            android:layout_toRightOf="@+id/add_component_btn"
            android:layout_marginLeft="10dp"
            android:background="@drawable/cancel"/>

    </RelativeLayout>

</LinearLayout>

Answer 1

您的 damageComponenetAutoCompleteTextview 似乎属于您在顶部膨胀的 popupWindow。

所以尝试改变

 damageComponenetAutoCompleteTextview = (AutoCompleteTextView) findViewById(R.id.popup_damage_component_item);

到

damageComponenetAutoCompleteTextview = (AutoCompleteTextView) popupView.findViewById(R.id.popup_damage_component_item);

以及其他相关元素。