如何回傳在串列視圖上單擊的專案的索引androidstudion代碼

正如我的代碼所示，我想根據專案的位置打開一個新的活動，點擊串列視圖。我對每個位置都有這個 if else 陳述句。它作業正常，因為我的串列只需要 3 個專案，但是如果我有一個很長的串列（比如 20 個專案）怎么辦？我怎樣才能得到點擊的專案的位置？

感謝您抽出寶貴時間來回答。這是我當前的代碼

lv_places.setAdapter(new ArrayAdapter(this, android.R.layout.simple_list_item_1,savedAddresses));

    lv_places.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
           

            if(position == 0) {
                // open map activity
                Intent i = new Intent(showSavedLocationsList.this, MapsActivity.class);
                i.putExtra("lat", savedLocations.get(0).getLatitude());
                i.putExtra("long", savedLocations.get(0).getLongitude());

                startActivity(i);
            }
            else if(position == 1){
                // open map activity
                Intent i = new Intent(showSavedLocationsList.this, MapsActivity.class);
                i.putExtra("lat", savedLocations.get(1).getLatitude());
                i.putExtra("long", savedLocations.get(1).getLongitude());

                startActivity(i);
            }
            else if(position == 2){
                // open map activity
                Intent i = new Intent(showSavedLocationsList.this, MapsActivity.class);
                i.putExtra("lat", savedLocations.get(2).getLatitude());
                i.putExtra("long", savedLocations.get(2).getLongitude());

                startActivity(i);
            }
            else if(position == 3){
                // open map activity
                Intent i = new Intent(showSavedLocationsList.this, MapsActivity.class);
                i.putExtra("lat", savedLocations.get(3).getLatitude());
                i.putExtra("long", savedLocations.get(3).getLongitude());

                startActivity(i);
            }


        }
    });

uj5u.com熱心網友回復：

您有一個位置編號作為引數，因此您可以優化您的代碼：

 lv_places.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
           
            Intent i = new Intent(showSavedLocationsList.this, MapsActivity.class);
            i.putExtra("lat", savedLocations.get(position).getLatitude());
            i.putExtra("long", savedLocations.get(position).getLongitude());

            startActivity(i);
      
            }
});

uj5u.com熱心網友回復：

lv_places.setAdapter(new ArrayAdapter(this, android.R.layout.simple_list_item_1, savedAddresses));

    lv_places.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position/*weGetVariableHere*/, long id) {
           
                // open map activity
                Intent i = new Intent(showSavedLocationsList.this, MapsActivity.class);
                i.putExtra("lat", savedLocations.get(position/*variableUsedHere*/).getLatitude());
                i.putExtra("long", savedLocations.get(position/*variableUsedHere*/).getLongitude());

                startActivity(i);
            


        }
    });

我們正在使用變數本身而不是 if-else-elseif 它適用于n專案數

uj5u.com熱心網友回復：

您可以使用如下所示的直接位置

lv_places.setOnItemClickListener(new AdapterView.OnItemClickListener() {
    @Override
    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
      
   
            // open map activity
            Intent i = new Intent(showSavedLocationsList.this, MapsActivity.class);
            i.putExtra("lat", savedLocations.get(position).getLatitude());
            i.putExtra("long", savedLocations.get(position).getLongitude());

            startActivity(i);

    }
});

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