如何刪除我在 String[] Android 中單擊的數據

Question

我有意從另一個 class 獲取 String[] 中的數據。 我在列表視圖中顯示我收到的數據。 當我單擊自定義適配器上的 deleteshop 按鈕時，我希望從字符串數組中刪除我單擊的數據。 我怎樣才能做到這一點？

我的代碼；

        final ListView list = findViewById(R.id.list);

        final ArrayList<SubjectData> arrayList = new ArrayList<SubjectData>();

        final String[] cartList = getIntent().getStringArrayExtra("saleData");

        arrayList.add(new SubjectData("", ""));

        final int cartListLength = cartList.length;
        int counter = 0;
        String lastItem = "";


        for (String e : cartList) {
            counter += 1;
            if (e == "" || e == null) {
                lastItem = cartList[counter-3];
                break;
            }

            String productPhoto = "";

            switch (e) {
                case "1 PC GREEN COLA x 10.00 TL":
                    productPhoto = "cc";
                    break;

                default:
                    productPhoto = "";
                    break;            }

          
        arrayList.add(new SubjectData(e,  productPhoto));;
        }
        arrayList.remove(arrayList.size()-1);
        arrayList.remove(arrayList.size()-1);
     

        final CustomAdapter customAdapter = new CustomAdapter(this, arrayList);
        list.setAdapter(customAdapter);

nextButton.setOnTouchListener(new View.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                final int action = event.getAction();
                switch (action) {
                    case MotionEvent.ACTION_DOWN:
                        nextButton.setImageResource(R.drawable.next_down);
                        break;
                    case MotionEvent.ACTION_UP:
                        nextButton.setImageResource(R.drawable.next_up);
                        Intent myIntent = new Intent(getApplicationContext(), PrinterManagerActivity.class);
                        myIntent.putExtra("saleData", cartList);
                        startActivityForResult(myIntent, 0);
                        //
                        break;
                }
                return true;
            }
        });

主題數據 model class：

    String SubjectName;
    String Image;

    public SubjectData(String subjectName, String image) {
        this.SubjectName = subjectName;
        this.Image = image;
    }

定制適配器；

class CustomAdapter implements ListAdapter {
    ArrayList<SubjectData> arrayList;
    Context context;
    public CustomAdapter(Context context, ArrayList<SubjectData> arrayList) {
        this.arrayList=arrayList;
        this.context=context;
    }

    @Override
    public boolean areAllItemsEnabled() {
        return false;
    }

    @Override
    public boolean isEnabled(int position) {
        return true;
    }

    @Override
    public void registerDataSetObserver(DataSetObserver observer) {

    }

    @Override
    public void unregisterDataSetObserver(DataSetObserver observer) {

    }

    @Override
    public int getCount() {
        return arrayList.size();
    }

    @Override
    public Object getItem(int position) {
        return position;
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public boolean hasStableIds() {
        return false;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        final SubjectData subjectData=arrayList.get(position);
        if(convertView==null){
            LayoutInflater layoutInflater = LayoutInflater.from(context);
            convertView=layoutInflater.inflate(R.layout.list_row, null);
        
            TextView tittle=convertView.findViewById(R.id.title);
            ImageView imag=convertView.findViewById(R.id.list_image);
            ImageView 
            deleteshop=convertView.findViewById(R.id.deleteshop);

            deleteshop.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View view) {                   
                        if (context instanceof SaleSummary) {
                            ((SaleSummary)context).deleteItem(position);

                            int selectedFromList = (int) list.getItemAtPosition(position);

                            String gettextdata = tittle.getText().toString();
                            Toast.makeText(context, gettextdata""+"the product has been deleted
", Toast.LENGTH_LONG).show();
                        }
                    }
                });
             
            tittle.setText(subjectData.SubjectName);
            Resources resources = context.getResources();
            final int resourceId = resources.getIdentifier(subjectData.Image, "drawable",
                    context.getPackageName());

           

            imag.setImageResource(resourceId);

          

        }
        return convertView;
    }

    @Override
    public int getItemViewType(int position) {
        return position;
    }

    @Override
    public int getViewTypeCount() {
        return arrayList.size();
    }


    @Override
    public boolean isEmpty() {
        return false;
    }

列表視圖設計；

<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"

    android:padding="5dip">

    <LinearLayout
        android:id="@+id/thumbnail"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_marginRight="5dip"
        android:padding="3dip">

        <ImageView
            android:id="@+id/list_image"
            android:layout_width="50dip"
            android:layout_height="50dip" />

    </LinearLayout>

    <TextView
        android:id="@+id/title"
        android:layout_width="250dp"
        android:layout_height="match_parent"
        android:layout_alignTop="@+id/thumbnail"
        android:layout_toRightOf="@+id/thumbnail"
        android:gravity="center"
        android:textColor="#040404"
        android:textSize="15dip"
        android:textStyle="bold"
        android:typeface="sans" />


    <ImageView
        android:layout_gravity="center"
        android:id="@+id/deleteshop"
        android:src="@drawable/negative"
        android:layout_width="25dp"
        android:layout_height="25dp" ></ImageView>



</LinearLayout>

Answer 1

這基本上是從數組中刪除數據，這是正常的編程/數據結構任務。

您可以在 cartList 上運行 for 循環，當您遇到要刪除的項目時，您可以簡單地用下一個項目覆蓋該項目，直到到達列表末尾，然后將最后一個項目標記為 null。

for(int i ==0; i < cartList.length(); i++){
  if(cartList[i] == selectedItem){
    for(int j = i j < cartList.length(); j++){
      cartList[j] == cartList[j++];
    }
    // mark last item as null
    cartList[cartList.length()-1] = null;
    break;
  }
}

您現在需要的只是您的活動和適配器之間的偵聽器，只要用戶單擊任何項目上的刪除項目，它將觸發邏輯。