I'm writing a MEMO app, but there have some problum When I want to edit MEMO, whatever item I choose , it always only change the first item, It only got the item number in front of the string Like this I want the result that I can change any item which I click

This is my code:

public class d_Game_message extends AppCompatActivity
       implements AdapterView.OnItemClickListener, AdapterView.OnItemLongClickListener {

   private static final int REQUEST_CODE_EDIT = 1;

   String[] aMemo ={
           "1.按一下可以編輯備忘",
           "2.長按可以清除備忘","3.","4.","5.","6."};
   ListView lv;
   ArrayAdapter<String> aa;



   @Override
   protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_dgame_message);

       lv = (ListView)findViewById(R.id.listView);
       aa = new ArrayAdapter<>(this,
               android.R.layout.simple_list_item_1, aMemo);

       lv.setAdapter(aa);    

       lv.setOnItemClickListener(this);
       lv.setOnItemLongClickListener(this);

   @Override
   public void onItemClick(AdapterView<?> a, View v, int pos, long id) {
       Intent it = new Intent(this, d_Game_message_edit.class);
       it.putExtra("requestCode",pos);      //附加編號
       it.putExtra("memo", aMemo[pos]); //附加備忘項目的內容
       activityResultLaunch.launch(it);
   }


   @Override
   public boolean onItemLongClick(AdapterView<?> a, View v, int pos, long id) {
       aMemo[pos] = (pos 1)   "."; //將內容清除 (只剩編號)
       aa.notifyDataSetChanged();  //通知 Adapter 要更新陣列內容
       return true;                //傳回 true 表示此事件已處理
   }
   

   ActivityResultLauncher<Intent> activityResultLaunch = registerForActivityResult(
           new ActivityResultContracts.StartActivityForResult(),
           new ActivityResultCallback<ActivityResult>() {
               @Override
               public void onActivityResult(ActivityResult result) {
                   if (result.getResultCode() == RESULT_OK) {
                       Intent data = result.getData();
                       int requestCode = data.getIntExtra("requestCode", 0);
                       aMemo[requestCode] = data.getStringExtra("memo"); 
                       aa.notifyDataSetChanged(); 
                   }
               }
           });

This is edit activity

public class d_Game_message_edit extends AppCompatActivity {

   TextView txv;
   EditText edt;

   @Override
   protected void onCreate(Bundle savedInstanceState) {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_dgame_message_edit);

       Intent it = getIntent();               
       String s = it.getStringExtra("memo");  

       txv = (TextView)findViewById(R.id.textView);
       txv.setText(s.substring(0, 2));                 
       edt = (EditText)findViewById(R.id.editText);
       if(s.length() > 3)
           edt.setText(s.substring(2)); 
   }

   public void onCancel(View v) {  
       setResult(RESULT_CANCELED);
       finish();    
   }

   public void onSave(View v) {    
       Intent it2 = new Intent();
       it2.putExtra("memo", txv.getText()   " "   edt.getText()); 
       setResult(RESULT_OK, it2); 
       finish();    
   }
   }

I am a novice, thanks a lot for the help!!

CodePudding user response：

In Activity in onSave you are setting "memo" text, but you are not returning your "requestCode", thus int requestCode = data.getIntExtra("requestCode", 0); is always 0 (as 0 set as default param when lack of "requestCode" key), so edited item will always be this one on position = 0.

Store passed "requestCode" in d_Game_message_edit Activity (read it in onCreate)

...
private int position = 0;

@Override
protected void onCreate(Bundle savedInstanceState) {
   super.onCreate(savedInstanceState);
   setContentView(R.layout.activity_dgame_message_edit);

   Intent it = getIntent();               
   String s = it.getStringExtra("memo"); 
   position = it.getIntExtra("requestCode");
   ...

and return it in same Intent next to "memo" text when onSave runs

public void onSave(View v) {    
    Intent it2 = new Intent();
    it2.putExtra("memo", txv.getText()   " "   edt.getText());
    it2.putExtra("requestCode", position);
    setResult(RESULT_OK, it2); 
    finish();    
}

And change "requestCode" naming, it may be confusing...