Uygulamamda yapıyorum ve konsolda bu hatayı alıyorum "java.lang.RuntimeException: Etkinlik başlatılamadı ComponentInfo {com.example.cassieleong.delishcart/com.example.cassieleong.delishcart.FruitMain }: java.lang.NullPointerException: sanal yöntem 'void android.widget.ListView.setAdapter (android.widget.ListAdapter)' null bir nesne başvurusu çağrılmayı deneyin "Android App Hatası
Liste görünümü içeren bir etkinlik oluşturmaya çalışıyorum checkboxtextview ile.
Bu hatayı nasıl çözeceğimi bilmiyorum. Lütfen yardım et. Çok teşekkürler.
Java.
public class FruitMain extends AppCompatActivity {
ListView listView;
String[] fruit;
Context context;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_fruit_main);
context = this;
listView = (ListView) findViewById(R.id.listView4);
String [] fruit = {"Apple","Applesauce","Apricot","Banana","Barlett Pears","Blackberries","Blueberries","Cantaloupe","Cherry","Citron","Coconut","Cranberry",
"Currants","Dates","Dried Fruit","Fig","Fruit Cocktail","Fruit Sauce","Grape","Grapefruit","Green Grapes","Honeydew Melon","Juniper Berries","Kiwi",
"Kumquat","Lemon","Lime","Lime Juice","Mango","Nectarines","Orange","Papaya","Passion Fruit","Peach","Pear","Persimmon",
"Pineapple","Plantain","Plum","Plum Tomatoes","Pomegranate","Prunes","Raison","Raspberry","Red Grapes","Strawberry","Sweet Cherries","Tangerine",
"Watermelon"};
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, R.layout.fruititem_list, fruit);
listView.setAdapter(adapter);
listView.setItemsCanFocus(false);
listView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
//Inflate the menu; this adds item to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_ingredient_choices, menu);
return true;
}
}
XML.
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:context="com.example.cassieleong.delishcart.FruitMain"
tools:showIn="@layout/activity_fruit_main">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text=" Fruit Product "
android:id="@+id/textView6"
android:textSize="35dp"
android:background="#f97c7c"
android:layout_alignParentTop="true"
android:layout_alignParentStart="true" />
<ListView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/listView5"
android:layout_below="@+id/textView6"
android:layout_alignParentStart="true"
android:layout_above="@+id/button2"
android:layout_alignParentEnd="true"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Submit"
android:id="@+id/button3"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true" />
XML
<CheckedTextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/checkedTextView4"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text=""
android:gravity="center"
android:drawableLeft="?android:attr/listChoiceIndicatorMultiple"
android:textSize="25dp">
! Yaptığım minik hataları işaret ettiğin için teşekkürler! –