[英]How to delete push key data from Firebase in Android Studio
[英]How to delete data from firebase android
要刪除數據,請執行以下操作:
DatabaseReference data = FirebaseDatabase.getInstance().getReference().child("Marks");
data.orderByChild("enrollment").equalTo("66").addListenerForSingleValueEvent(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
for(DataSnapshot data: dataSnapshot.getChildren()){
data.getRef().removeValue();
}
}
@Override
public void onCancelled(DatabaseError databaseError) {
}
});
添加對子Marks
的引用,然后使用查詢orderByChild
您可以獲得正確的節點並將其刪除
試試這個代碼。
int enrollmentId = Integer.parseInt( et1.getText().toString() );
reff.child("Marks").orderByChild("enrollment").equalTo(enrollmentId)
.addListenerForSingleValueEvent(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot dataSnapshot)
{
for (DataSnapshot ds : dataSnapshot.getChildren())
{
ds.getRef().removeValue();
Toast.makeText(context, "Deleted", Toast.LENGTH_SHORT).show();
}
}
@Override
public void onCancelled(@NonNull DatabaseError databaseError)
{
Toast.makeText(context, "Failed to delete", Toast.LENGTH_SHORT).show();
}
});
String et1 =e1.getText().toString().trim();
reff.child("Marks").orderByChild("enrollment").equalTo(et1)
.addListenerForSingleValueEvent(new ValueEventListener() {
@Override
public void onDataChange(@NonNull DataSnapshot dataSnapshot)
{
for (DataSnapshot ds : dataSnapshot.getChildren())
{
ds.getRef().removeValue();
Toast.makeText(getApplicationContext(), "Deleted", Toast.LENGTH_SHORT).show();
}
}
@Override
public void onCancelled(@NonNull DatabaseError databaseError)
{
Toast.makeText(getApplicationContext(), "Failed to delete", Toast.LENGTH_SHORT).show();
}
});
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