Type mismatch:cannot convert void to toast
i have a method in my main activity which is of void return type.if i create a Toast inside the method it shows the error "Type mismatch:cannot convert void to toast". can anyone explain what is the problem and help me with solution ?
public class HelloList<View> extends ListActivity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setListAdapter(new ArrayAdapter<String>(this, R.layout.list_item, COUNTRIES));
ListView lv=getListV开发者_运维问答iew();
lv.setTextFilterEnabled(true);
lv.setOnItemClickListener(new OnItemClickListener(){
@Override
public void onItemClick(AdapterView<?> arg0,android.view.View arg1, int arg2, long arg3) {
// TODO Auto-generated method stub
// Toast.makeText(getApplicationContext(), ((TextView) arg1).getText(),Toast.LENGTH_SHORT).show();
System.out.println(arg2);
String s="position is "+arg2;
Toast.makeText(getApplicationContext(),s,Toast.LENGTH_SHORT).show();
}
});
registerForContextMenu(lv);
/*int i=lv.getCheckedItemPosition();
Toast.makeText(getApplicationContext(),,Toast.LENGTH_SHORT).show();*/
}
public void onCreateContextMenu(ContextMenu menu, android.view.View v,
ContextMenuInfo menuInfo) {
super.onCreateContextMenu(menu, v, menuInfo);
MenuInflater inflater = getMenuInflater();
inflater.inflate(0x7f030000, menu);
}
public boolean onContextItemSelected(MenuItem item) {
AdapterContextMenuInfo info = (AdapterContextMenuInfo) item.getMenuInfo();
switch (item.getItemId()) {
case 0x7f030000:
editNote(info.id);
return true;
default:
return super.onContextItemSelected(item);
}
}
public void editNote(long id) {
Toast m=Toast.makeText(this, "asdasd", 3);
m.show();
}
The problem is that you can assign a method to a variable. A toast should look like this if you want to directly display it:
Toast.makeText(context, text, duration).show();
or in your case:
Toast.makeText(this, "sadasd", 2).show();
If you want to store the Toast in a variable and then display it, you have to do it like this:
Toast toast = Toast.makeText(context, text, duration);
toast.show();
Or in your specific case:
Toast toast = Toast.makeText(this, "sadasd", 2);
toast.show();
On a side note: It would be better to use the constants LENGHT_SHORT and LENGTH_LONG in Toast to define the duration instead of 2. Especially if 2 does not seem to be a valid value here. See here fore more details: http://developer.android.com/reference/android/widget/Toast.html
Then it would look like this:
Toast.makeText(this, "sadasd", Toast.LENGTH_LONG).show();
Toast m=Toast.makeText(this, "sadasd", 2);
m.show();
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