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QGeoCodeReply Class

The QGeoCodeReply class manages an operation started by an instance of QGeoCodingManager . 更多...

头： #include <QGeoCodeReply>
qmake: QT += location
Since: Qt 5.6
继承： QObject

公共类型

enum Error { NoError, EngineNotSetError, CommunicationError, ParseError, ..., UnknownError }

公共函数

QGeoCodeReply (Error error , const QString & errorString , QObject * parent = Q_NULLPTR)
virtual ~QGeoCodeReply ()
virtual void abort ()
Error error () const
QString errorString () const
bool isFinished () const
int limit () const
QList<QGeoLocation> locations () const
int offset () const
QGeoShape viewport () const

信号

void aborted ()
void error (QGeoCodeReply::Error error , const QString & errorString = QString())
void finished ()

保护函数

QGeoCodeReply (QObject * parent = Q_NULLPTR)
void addLocation (const QGeoLocation & location )
void setError (Error error , const QString & errorString )
void setFinished (bool finished )
void setLimit (int limit )
void setLocations (const QList<QGeoLocation> & locations )
void setOffset (int offset )
void setViewport (const QGeoShape & viewport )

额外继承成员

详细描述

The QGeoCodeReply class manages an operation started by an instance of QGeoCodingManager .

实例化的 QGeoCodeReply manage the state and results of these operations.

The isFinished (), error () 和 errorString () methods provide information on whether the operation has completed and if it completed successfully.

The finished () and error( QGeoCodeReply::Error , QString ) signals can be used to monitor the progress of the operation.

It is possible that a newly created QGeoCodeReply may be in a finished state, most commonly because an error has occurred. Since such an instance will never emit the finished () or error( QGeoCodeReply::Error , QString ) signals, it is important to check the result of isFinished () before making the connections to the signals. The documentation for QGeoCodingManager demonstrates how this might be carried out.

If the operation completes successfully the results will be able to be accessed with locations ().

成员类型文档编制

enum QGeoCodeReply:: Error

Describes an error which prevented the completion of the operation.

常量 值 描述
QGeoCodeReply::NoError 0 没有出现错误。
QGeoCodeReply::EngineNotSetError 1 The geocoding manager that was used did not have a QGeoCodingManagerEngine instance associated with it.
QGeoCodeReply::CommunicationError 2 An error occurred while communicating with the service provider.
QGeoCodeReply::ParseError 3 The response from the service provider was in an unrecognizable format.
QGeoCodeReply::UnsupportedOptionError 4 The requested operation or one of the options for the operation are not supported by the service provider.
QGeoCodeReply::CombinationError 5 An error occurred while results where being combined from multiple sources.
QGeoCodeReply::UnknownError 6 An error occurred which does not fit into any of the other categories.

成员函数文档编制

QGeoCodeReply:: QGeoCodeReply ( Error error , const QString & errorString , QObject * parent = Q_NULLPTR)

Constructs a geocode reply with a given error and errorString and the specified parent .

[protected] QGeoCodeReply:: QGeoCodeReply ( QObject * parent = Q_NULLPTR)

Constructs a geocode reply with the specified parent .

[虚拟] QGeoCodeReply:: ~QGeoCodeReply ()

Destroys this reply object.

[虚拟] void QGeoCodeReply:: abort ()

Cancels the operation immediately.

This will do nothing if the reply is finished.

另请参阅 aborted ().

[signal] void QGeoCodeReply:: aborted ()

This signal is emitted when the operation has been cancelled.

该函数在 Qt 5.9 引入。

另请参阅 abort ().

[protected] void QGeoCodeReply:: addLocation (const QGeoLocation & location )

添加 location to the list of locations in this reply.

Error QGeoCodeReply:: error () const

Returns the error state of this reply.

若结果为 QGeoCodeReply::NoError then no error has occurred.

另请参阅 setError ().

[signal] void QGeoCodeReply:: error ( QGeoCodeReply::Error error , const QString & errorString = QString())

This signal is emitted when an error has been detected in the processing of this reply. The finished () signal will probably follow.

The error will be described by the error code error 。若 errorString is not empty it will contain a textual description of the error.

This signal and QGeoCodingManager::error () will be emitted at the same time.

注意： Do not delete this reply object in the slot connected to this signal. Use deleteLater () 代替。

注意： 信号 error 在此类中是重载。要使用函数指针句法连接到此信号，必须在静态铸造中指定信号类型，如此范例所示： 

connect(geoCodeReply, static_cast<void(QGeoCodeReply::*)(QGeoCodeReply::Error, const QString &)>(&QGeoCodeReply::error),
    [=](QGeoCodeReply::Error error, const QString &errorString){ /* ... */ });

QString QGeoCodeReply:: errorString () const

Returns the textual representation of the error state of this reply.

If no error has occurred this will return an empty string. It is possible that an error occurred which has no associated textual representation, in which case this will also return an empty string.

To determine whether an error has occurred, check to see if QGeoCodeReply::error () is equal to QGeoCodeReply::NoError .

[signal] void QGeoCodeReply:: finished ()

This signal is emitted when this reply has finished processing.

若 error () 等于 QGeoCodeReply::NoError then the processing finished successfully.

This signal and QGeoCodingManager::finished () will be emitted at the same time.

注意： Do not delete this reply object in the slot connected to this signal. Use deleteLater () 代替。

另请参阅 setFinished ().

bool QGeoCodeReply:: isFinished () const

Return true if the operation completed successfully or encountered an error which cause the operation to come to a halt.

int QGeoCodeReply:: limit () const

Returns the limit on the number of responses from each data source.

If no limit was set this function will return -1.

This may be more than locations ().length() if the number of responses was less than the number requested.

另请参阅 setLimit ().

QList < QGeoLocation > QGeoCodeReply:: locations () const

Returns a list of locations.

The locations are the results of the operation corresponding to the QGeoCodingManager function which created this reply.

另请参阅 setLocations ().

int QGeoCodeReply:: offset () const

Returns the offset into the entire result set at which to start fetching results.

另请参阅 setOffset ().

[protected] void QGeoCodeReply:: setError ( Error error , const QString & errorString )

Sets the error state of this reply to error and the textual representation of the error to errorString .

This will also cause error () 和 finished () signals to be emitted, in that order.

另请参阅 error ().

[protected] void QGeoCodeReply:: setFinished ( bool finished )

Sets whether or not this reply has finished to finished .

若 finished is true, this will cause the finished () 信号被发射。

If the operation completed successfully, QGeoCodeReply::setLocations () should be called before this function. If an error occurred, QGeoCodeReply::setError () 应该被使用以取而代之。

另请参阅 finished ().

[protected] void QGeoCodeReply:: setLimit ( int limit )

Sets the limit on the number of responses from each data source to limit .

若 limit is -1 then all available responses will be returned.

另请参阅 limit ().

[protected] void QGeoCodeReply:: setLocations (const QList < QGeoLocation > & locations )

Sets the list of locations in the reply.

另请参阅 locations ().

[protected] void QGeoCodeReply:: setOffset ( int offset )

Sets the offset in the entire result set at which to start fetching result to offset .

另请参阅 offset ().

[protected] void QGeoCodeReply:: setViewport (const QGeoShape & viewport )

Sets the viewport which contains the results to viewport .

另请参阅 viewport ().

QGeoShape QGeoCodeReply:: viewport () const

Returns the viewport which contains the results.

This function will return 0 if no viewport bias was specified in the QGeoCodingManager function which created this reply.

另请参阅 setViewport ().