public class
Query
extends Object
Known Direct Subclasses |
The Query class (and its subclass, DatabaseReference
) are used for reading data.
Listeners are attached, and they will be triggered when the corresponding data changes.
Instances of Query are obtained by calling startAt(), endAt(), or limit() on a DatabaseReference.
Public Method Summary
ChildEventListener |
addChildEventListener(ChildEventListener listener)
Add a listener for child events occurring at this location.
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void |
addListenerForSingleValueEvent(ValueEventListener listener)
Add a listener for a single change in the data at this location.
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ValueEventListener |
addValueEventListener(ValueEventListener listener)
Add a listener for changes in the data at this location.
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Query |
endAt(String value, String key)
Create a query constrained to only return child nodes with a value less than or equal to the
given value, using the given orderBy directive or priority as default, and additionally only
child nodes with a key key less than or equal to the given key.
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Query |
endAt(String value)
Create a query constrained to only return child nodes with a value less than or equal to the
given value, using the given orderBy directive or priority as default.
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Query |
endAt(double value, String key)
Create a query constrained to only return child nodes with a value less than or equal to the
given value, using the given orderBy directive or priority as default, and additionally only
child nodes with a key less than or equal to the given key.
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Query |
endAt(double value)
Create a query constrained to only return child nodes with a value less than or equal to the
given value, using the given orderBy directive or priority as default.
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Query |
endAt(boolean value)
Create a query constrained to only return child nodes with a value less than or equal to the
given value, using the given orderBy directive or priority as default.
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Query |
endAt(boolean value, String key)
Create a query constrained to only return child nodes with a value less than or equal to the
given value, using the given orderBy directive or priority as default, and additionally only
child nodes with a key less than or equal to the given key.
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Query |
equalTo(String value, String key)
Create a query constrained to only return the child node with the given key and value.
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Query |
equalTo(double value)
Create a query constrained to only return child nodes with the given value.
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Query |
equalTo(double value, String key)
Create a query constrained to only return the child node with the given key and value.
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Query |
equalTo(String value)
Create a query constrained to only return child nodes with the given value.
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Query |
equalTo(boolean value, String key)
Create a query constrained to only return the child node with the given key and value.
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Query |
equalTo(boolean value)
Create a query constrained to only return child nodes with the given value.
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DatabaseReference |
getRef()
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void |
keepSynced(boolean keepSynced)
By calling
keepSynced(true) on a location, the data for that location will
automatically be downloaded and kept in sync, even when no listeners are attached for that
location. |
Query |
limitToFirst(int limit)
Create a query with limit and anchor it to the start of the window.
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Query |
limitToLast(int limit)
Create a query with limit and anchor it to the end of the window.
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Query |
orderByChild(String path)
Create a query in which child nodes are ordered by the values of the specified path.
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Query |
orderByKey()
Create a query in which child nodes are ordered by their keys.
|
Query |
orderByPriority()
Create a query in which child nodes are ordered by their priorities.
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Query |
orderByValue()
Create a query in which nodes are ordered by their value
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void | |
void | |
Query |
startAt(double value)
Create a query constrained to only return child nodes with a value greater than or equal to the
given value, using the given orderBy directive or priority as default.
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Query |
startAt(String value, String key)
Create a query constrained to only return child nodes with a value greater than or equal to the
given value, using the given orderBy directive or priority as default, and additionally only
child nodes with a key greater than or equal to the given key.
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Query |
startAt(String value)
Create a query constrained to only return child nodes with a value greater than or equal to the
given value, using the given orderBy directive or priority as default.
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Query |
startAt(double value, String key)
Create a query constrained to only return child nodes with a value greater than or equal to the
given value, using the given orderBy directive or priority as default, and additionally only
child nodes with a key greater than or equal to the given key.
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Query |
startAt(boolean value)
Create a query constrained to only return child nodes with a value greater than or equal to the
given value, using the given orderBy directive or priority as default.
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Query |
startAt(boolean value, String key)
Create a query constrained to only return child nodes with a value greater than or equal to the
given value, using the given orderBy directive or priority as default, and additionally only
child nodes with a key greater than or equal to the given key.
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