I'm new developer. Trying to build simple app using custom list view. And its open pretty well but when I click its not working anymore. After I add exception, I can see that Null Pointer Exception. Confused how do i fix it. Code are below: Please help me out. Problem Solved. Code Has Been Updated Below:
public class MainActivity extends AppCompatActivity {
private static final String TAG = "MainActivity";
private ListView mListView;
private Toolbar toolbarTop;
private TextView mTitle;
private String[] mCountryNames;
private int[] flags = {
R.drawable.flag_afghanistan,
R.drawable.flag_armenia,
R.drawable.flag_australia,
R.drawable.flag_azerbaijan,
R.drawable.flag_bahrain,
R.drawable.flag_bangladesh,
R.drawable.flag_bhutan,
R.drawable.flag_china,
R.drawable.flag_hongkong,
R.drawable.flag_india,
R.drawable.flag_malaysia,
R.drawable.flag_nepal,
R.drawable.flag_pakistan,
R.drawable.flag_philippines,
R.drawable.flag_singapore,
R.drawable.flag_thailand,
R.drawable.flag_unitedstates
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Log.d(TAG, "onCreate: started");
toolbarTop = findViewById(R.id.toolBarId);
mTitle = toolbarTop.findViewById(R.id.toolbar_title);
mListView = findViewById(R.id.listViewId);
mCountryNames = getResources().getStringArray(R.array.country_names);
CustomAdapter mAdapter = new CustomAdapter(this,mCountryNames,flags);
mListView.setAdapter(mAdapter);
mListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
try{
Log.d("Click", "onItemClick: Working ");
Intent intent = new Intent(MainActivity.this,SecondActivity.class);
intent.putExtra("CountryNames", mCountryNames[position].toString());
startActivity(intent);
}catch (Exception e){
Toast.makeText(getApplicationContext(),"Something Went Wrong: "+" "+e,Toast.LENGTH_SHORT).show();
}
}
});
Activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:orientation="vertical"
tools:context=".MainActivity">
<android.support.v7.widget.Toolbar
android:id="@+id/toolBarId"
android:gravity="center"
android:layout_gravity="center"
android:background="@color/colorPrimary"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<TextView
android:text="Country Names"
android:textSize="22sp"
android:textColor="#fff"
android:textStyle="bold"
android:layout_gravity="center"
android:id="@+id/toolbar_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</android.support.v7.widget.Toolbar>
<ListView
android:id="@+id/listViewId"
android:listSelector="#faf5f7"
android:layout_width="match_parent"
android:layout_height="match_parent">
</ListView>
</LinearLayout>
row_view.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:orientation="vertical"
android:padding="10dp"
android:layout_marginTop="15dp"
tools:context=".MainActivity">
<LinearLayout
android:padding="5dp"
android:background="@drawable/background"
android:weightSum="4"
android:layout_marginTop="5dp"
android:layout_marginBottom="5dp"
android:layout_width="match_parent"
android:layout_height="65dp">
<ImageView
android:id="@+id/imageViewId"
android:background="#bdc3c7"
android:src="@drawable/flag_bangladesh"
android:layout_weight="1"
android:layout_width="0dp"
android:layout_height="wrap_content" />
<LinearLayout
android:layout_weight="3"
android:layout_width="0dp"
android:layout_height="match_parent">
<TextView
android:id="@+id/textViewId"
android:background="#7f8c8d"
android:text="Hello World"
android:textColor="#fff"
android:textAppearance="@style/Base.TextAppearance.AppCompat.Large"
android:gravity="center"
android:textStyle="bold"
android:layout_weight="2"
android:layout_width="0dp"
android:layout_height="match_parent" />
<LinearLayout
android:background="#95a5a6"
android:layout_weight="0.5"
android:layout_width="0dp"
android:layout_height="match_parent">
<ImageView
android:src="@drawable/arrow"
android:layout_gravity="center"
android:layout_weight="0.5"
android:layout_width="0dp"
android:layout_height="32dp" />
</LinearLayout>
</LinearLayout>
</LinearLayout>
</LinearLayout>
Please help me out
Logcat
--------- beginning of system
2018-10-02 07:55:31.899 30580-2768/? I/ActivityManager: Killing 3578:com.google.android.gms:car/u0a12 (adj 906): empty #17
2018-10-02 07:55:33.056 30580-30596/? E/memtrack: Couldn't load memtrack module
2018-10-02 07:55:33.057 30580-30596/? W/android.os.Debug: failed to get memory consumption info: -1
2018-10-02 07:55:34.439 30580-30596/? E/memtrack: Couldn't load memtrack module
2018-10-02 07:55:34.439 30580-30596/? W/android.os.Debug: failed to get memory consumption info: -1
2018-10-02 07:55:34.460 30580-30596/? E/memtrack: Couldn't load memtrack module
2018-10-02 07:55:34.460 30580-30596/? W/android.os.Debug: failed to get memory consumption info: -1
Screenshot - Look Exception in Toast Message
