-5
Ich benutze Android Studio Ich habe versucht, eine AlertDialog zu erstellen, wenn die Schaltfläche geklickt wird, aber wenn ich versuche zu starten, stürzt die App ab. Bitte zeigen Sie mir klar die Lösung.Absturz Android-Anwendung
Ps: Der Button befindet sich in der Kartenansicht.
Haupt java:
public class MainActivity extends AppCompatActivity {
private RecyclerView recyclerView;
private ItemAdapter itemAdapter;
private Button b1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
b1 = (Button) findViewById(R.id.button1);
b1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
AlertDialog.Builder a_builder = new AlertDialog.Builder(MainActivity.this);
a_builder.setCancelable(false);
a_builder.setMessage("do you want to call!!!");
a_builder.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
Intent callIntent = new Intent(Intent.ACTION_CALL);
callIntent.setData(Uri.parse("tel:0000000000"));
if (ActivityCompat.checkSelfPermission(MainActivity.this, Manifest.permission.CALL_PHONE) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return;
}
startActivity(callIntent);
}
});
a_builder.setNegativeButton("No", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
});
AlertDialog alert = a_builder.create();
alert.setTitle("Alert !");
alert.show();
}
});
final Toolbar toolbar = (Toolbar)findViewById(R.id.MyToolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
CollapsingToolbarLayout collapsingToolbarLayout = (CollapsingToolbarLayout)findViewById(R.id.collapse_toolbar);
collapsingToolbarLayout.setTitle("Service/DPNG");
ArrayList<Celebrity> itemList = new ArrayList<>();
fillDummyData(itemList);
recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
itemAdapter = new ItemAdapter(itemList);
RecyclerView.LayoutManager mLayoutManager = new LinearLayoutManager(getApplicationContext());
recyclerView.setLayoutManager(mLayoutManager);
recyclerView.setItemAnimator(new DefaultItemAnimator());
recyclerView.setAdapter(itemAdapter);
}
private void fillDummyData(ArrayList<Celebrity> celebList) {
Celebrity celeb1 = new Celebrity();
celeb1.setName("Johny.D");
celeb1.setFamousMovie("Pirates ");
celeb1.setProfilePhotoLocation("@drawable/contact1");
celebList.add(celeb1);
Celebrity celeb2 = new Celebrity();
celeb2.setName("Arnold");
celeb2.setFamousMovie("The Terminator");
celeb2.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/[email protected]@._V1._SY209_CR13,0,140,209_.jpg");
celebList.add(celeb2);
Celebrity celeb3 = new Celebrity();
celeb3.setName("Emma.W");
celeb3.setFamousMovie("Harry Potter ");
celeb3.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/[email protected]_V1._SY209_CR14,0,140,209_.jpg");
celebList.add(celeb3);
Celebrity celeb4 = new Celebrity();
celeb4.setName("Daniel");
celeb4.setFamousMovie("Harry Potter ");
celeb4.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/[email protected]_V1._SY209_CR8,0,140,209_.jpg");
celebList.add(celeb4);
Celebrity celeb5 = new Celebrity();
celeb5.setName("Leonardo");
celeb5.setFamousMovie("Inception");
celeb5.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/[email protected]@._V1._SY209_CR7,0,140,209_.jpg");
celebList.add(celeb5);
Celebrity celeb6 = new Celebrity();
celeb6.setName("TomCr");
celeb6.setFamousMovie("Top Gun");
celeb6.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/[email protected]@._V1._SY209_CR9,0,140,209_.jpg");
celebList.add(celeb6);
Celebrity celeb7 = new Celebrity();
celeb7.setName("Charles.C");
celeb7.setFamousMovie("Modern Times");
celeb7.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/[email protected]_V1._SX140_CR0,0,140,209_.jpg");
celebList.add(celeb7);
Celebrity celeb8 = new Celebrity();
celeb8.setName("Morgan.F");
celeb8.setFamousMovie("The Shawshank ");
celeb8.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/[email protected]@._V1._SX140_CR0,0,140,209_.jpg");
celebList.add(celeb8);
Celebrity celeb9 = new Celebrity();
celeb9.setName("Tom.Ha");
celeb9.setFamousMovie("The Da Vinci Code");
celeb9.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/[email protected]@._V1._SY209_CR2,0,140,209_.jpg");
celebList.add(celeb9);
Celebrity celeb10 = new Celebrity();
celeb10.setName("Hugh ");
celeb10.setFamousMovie("The Prestige");
celeb10.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/[email protected]@._V1._SX140_CR0,0,140,209_.jpg");
celebList.add(celeb10);
Celebrity celeb11 = new Celebrity();
celeb11.setName("Matt ");
celeb11.setFamousMovie("The Bourne Identity");
celeb11.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/[email protected]@._V1._SY209_CR8,0,140,209_.jpg");
celebList.add(celeb11);
Celebrity celeb12 = new Celebrity();
celeb12.setName("Sylvester ");
celeb12.setFamousMovie("Rocky");
celeb12.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/MV5BMTQwMTk3NDU2OV5BMl5BanBnXkFtZT[email protected]@._V1._SY209_CR5,0,140,209_.jpg");
celebList.add(celeb12);
Celebrity celeb13 = new Celebrity();
celeb13.setName("Will ");
celeb13.setFamousMovie("Men in Black");
celeb13.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/[email protected]@._V1._SY209_CR2,0,140,209_.jpg");
celebList.add(celeb13);
Celebrity celeb14 = new Celebrity();
celeb14.setName("Steven ");
celeb14.setFamousMovie("Saving Private ");
celeb14.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/MV5BMTY1NjAzNzE1MV5BMl5BanBnXkFtZTYwNTk0ODc0._V1._SX140_CR0,0,140,209_.jpg");
celebList.add(celeb14);
Celebrity celeb15 = new Celebrity();
celeb15.setName("Al ");
celeb15.setFamousMovie("The Godfather");
celeb15.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/MV5BMTQzMzg1ODAyNl5BMl5BanBnXkFtZTYwMjAxODQ1._V1._SX140_CR0,0,140,209_.jpg");
celebList.add(celeb15);
Celebrity celeb16 = new Celebrity();
celeb16.setName("Robert");
celeb16.setFamousMovie("The Avengers");
celeb16.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/[email protected]_V1._SX140_CR0,0,140,209_.jpg");
celebList.add(celeb16);
Celebrity celeb17 = new Celebrity();
celeb17.setName("Nat");
celeb17.setFamousMovie("V for Vendetta");
celeb17.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/[email protected]@._V1._SY209_CR8,0,140,209_.jpg");
celebList.add(celeb17);
Celebrity celeb18 = new Celebrity();
celeb18.setName("Dwayne");
celeb18.setFamousMovie("WWE Raw");
celeb18.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/[email protected]_V1._SX140_CR0,0,140,209_.jpg");
celebList.add(celeb18);
Celebrity celeb19 = new Celebrity();
celeb19.setName("Jackie ");
celeb19.setFamousMovie("Jackie Chan ");
celeb19.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/[email protected]@._V1._SY209_CR5,0,140,209_.jpg");
celebList.add(celeb19);
Celebrity celeb20 = new Celebrity();
celeb20.setName("Scarlet");
celeb20.setFamousMovie("Lost in ");
celeb20.setProfilePhotoLocation("http://ia.media-imdb.com/images/M/[email protected]@._V1._SY209_CR16,0,140,209_.jpg");
celebList.add(celeb20);
}
}
logcat:
09-14 21:18:04.476 26368-26368/com.example.apollo.bbpp E/AndroidRuntime: FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.apollo.bbpp/com.example.apollo.bbpp.MainActivity}: java.lang.NullPointerException
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2074)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2099)
at android.app.ActivityThread.access$600(ActivityThread.java:138)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1205)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4929)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:798)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:565)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at com.example.apollo.bbpp.MainActivity.onCreate(MainActivity.java:48)
at android.app.Activity.performCreate(Activity.java:5254)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1082)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2038)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2099)
at android.app.ActivityThread.access$600(ActivityThread.java:138)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1205)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4929)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:798)
Ihr Fehler ist ein Nullpointer. Das bedeutet, dass etwas, auf das du dich beziehst, nicht da ist. Sie müssen sich die Zeilennummern im Logcat ansehen und feststellen, welche Zeile den Fehler verursacht. – durbnpoisn
Die Zeilennummern im Logcat lauten: Starten Sie in com.example.apollo.bbpp.MainActivity.onCreate (MainActivity.java:48). b1.setOnClickListener (new View.OnClickListener() { –
Bitte poste deine Layoutdatei activity_main.xml. Hast du einen Button button1 im Layout definiert? –