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GdaDataProxyGdaDataProxy — Proxy to hold modifications for any GdaDataModel, and provides the GdaDataModel interface itself |
gboolean | defer-sync | Read / Write |
GdaDataModel * | model | Read / Write / Construct |
gboolean | prepend-null-entry | Read / Write |
gint | sample-size | Read / Write / Construct |
void | filter-changed | Run First |
void | post-changes-applied | Run First |
gboolean | pre-changes-applied | Run Last |
void | row-delete-changed | Run First |
void | sample-changed | Run First |
void | sample-size-changed | Run First |
This object stores modifications to be made to a GdaDataModel object which is proxied until the modifications are actually written to the GdaDataModel, it can also filter the proxied data model to show only a subset (a defined number of continuous rows or by a filter to apply).
Specifically, for a proxied data model having nb_cols
columns and nb_rows
rows,
the GdaDataProxy object has the following attributes:
2 * nb_cols
columns:
the first (>= 0) nb_cols
columns are the current values stored in the
proxy (which correspond to the values of the proxied data model if the considered row has not been
changed). The associated values are writable.
the last nb_cols
columns are the values stored in the proxied data model,
at column col - nb_cols
a variable number of rows depending on the following attributes:
if the proxy is configured to have an empty row as the first row
if the proxy only displays parts of the proxied data model
if new rows have been added to the proxy
Note that unless explicitely mentionned, the columns are read-only.
GObject *
gda_data_proxy_new (GdaDataModel *model
);
Creates a new proxy for model
GdaDataModel *
gda_data_proxy_get_proxied_model (GdaDataProxy *proxy
);
Fetch the GdaDataModel which proxy
does proxy
gint
gda_data_proxy_get_proxied_model_n_cols
(GdaDataProxy *proxy
);
Get the number of columns in the proxied data model
gint
gda_data_proxy_get_proxied_model_n_rows
(GdaDataProxy *proxy
);
Get the number of rows in the proxied data model
GSList * gda_data_proxy_get_values (GdaDataProxy *proxy
,gint proxy_row
,gint *cols_index
,gint n_cols
);
Retreive a whole list of values from the proxy
store. This function calls gda_data_proxy_get_value()
for each column index specified in cols_index
, and generates a GSlist on the way.
GdaValueAttribute gda_data_proxy_get_value_attributes (GdaDataProxy *proxy
,gint proxy_row
,gint col
);
Get the attributes of the value stored at (proxy_row, col) in proxy
, which
is an ORed value of GdaValueAttribute flags
void gda_data_proxy_alter_value_attributes (GdaDataProxy *proxy
,gint proxy_row
,gint col
,GdaValueAttribute alter_flags
);
Alters the attributes of the value stored at (proxy_row, col) in proxy
. the alter_flags
can only contain the GDA_VALUE_ATTR_IS_NULL, GDA_VALUE_ATTR_IS_DEFAULT and GDA_VALUE_ATTR_IS_UNCHANGED
flags (other flags are ignored).
proxy |
a GdaDataProxy object |
|
proxy_row |
A proxy row number |
|
col |
a valid column number |
|
alter_flags |
flags to alter the attributes |
gint gda_data_proxy_get_proxied_model_row (GdaDataProxy *proxy
,gint proxy_row
);
Get the proxy
's proxied model row corresponding to proxy_row
void gda_data_proxy_delete (GdaDataProxy *proxy
,gint proxy_row
);
Marks the row proxy_row
to be deleted
void gda_data_proxy_undelete (GdaDataProxy *proxy
,gint proxy_row
);
Remove the "to be deleted" mark at the row proxy_row
, if it existed.
gboolean gda_data_proxy_row_is_deleted (GdaDataProxy *proxy
,gint proxy_row
);
Tells if the row number proxy_row
is marked to be deleted.
gboolean gda_data_proxy_row_is_inserted (GdaDataProxy *proxy
,gint proxy_row
);
Tells if the row number proxy_row
is a row which has been inserted in proxy
(and is thus not in the proxied data model).
gint gda_data_proxy_find_row_from_values (GdaDataProxy *proxy
,GSList *values
,gint *cols_index
);
Find the first row where all the values in values
at the columns identified at
cols_index
match.
NOTE: the cols_index
array MUST contain a column index for each value in values
proxy |
a GdaDataProxy object |
|
values |
a list of GValue values |
|
cols_index |
an array of gint containing the column number to match each value of |
void gda_data_proxy_cancel_row_changes (GdaDataProxy *proxy
,gint proxy_row
,gint col
);
Resets data at the corresponding row and column. If proxy_row
corresponds to a new row, then
that new row is deleted from proxy
.
proxy |
a GdaDataProxy object |
|
proxy_row |
the row to cancel changes |
|
col |
the column to cancel changes, or less than 0 to cancel any change on the |
gboolean gda_data_proxy_apply_row_changes (GdaDataProxy *proxy
,gint proxy_row
,GError **error
);
Commits the modified data in the proxy back into the GdaDataModel.
proxy |
a GdaDataProxy object |
|
proxy_row |
the row number to commit |
|
error |
place to store the error, or |
gboolean
gda_data_proxy_has_changed (GdaDataProxy *proxy
);
Tells if proxy
contains any modifications not applied to the proxied data model.
gboolean gda_data_proxy_row_has_changed (GdaDataProxy *proxy
,gint proxy_row
);
Tells if the row number proxy_row
has changed
gint
gda_data_proxy_get_n_new_rows (GdaDataProxy *proxy
);
Get the number of rows which have been added to proxy
and which are not part of
the proxied data model.
void gda_data_proxy_set_sample_size (GdaDataProxy *proxy
,gint sample_size
);
Sets the size of each chunk of fata to display: the maximum number of rows which can be displayed at a time. The default value is arbitrary 300 as it is big enough to be able to display quite a lot of data, but small enough to avoid too much data displayed at the same time.
Note: the rows which have been added but not yet commited will always be displayed regardless of the current chunk of data, and the modified rows which are not visible when the displayed chunk of data changes are still held as modified rows.
To remove the chunking of the data to display, simply pass sample_size
the 0 value.
gint
gda_data_proxy_get_sample_size (GdaDataProxy *proxy
);
Get the size of each chunk of data displayed at a time.
void gda_data_proxy_set_sample_start (GdaDataProxy *proxy
,gint sample_start
);
Sets the number of the first row to be displayed.
gint
gda_data_proxy_get_sample_start (GdaDataProxy *proxy
);
Get the row number of the first row to be displayed.
gint
gda_data_proxy_get_sample_end (GdaDataProxy *proxy
);
Get the row number of the last row to be displayed.
gboolean gda_data_proxy_apply_all_changes (GdaDataProxy *proxy
,GError **error
);
Apply all the changes stored in the proxy to the proxied data model. The changes are done row after row, and if an error occurs, then it is possible that not all the changes to all the rows have been applied.
gboolean
gda_data_proxy_cancel_all_changes (GdaDataProxy *proxy
);
Cancel all the changes stored in the proxy (the proxy
will be reset to its state
as it was just after creation).
gboolean gda_data_proxy_set_filter_expr (GdaDataProxy *proxy
,const gchar *filter_expr
,GError **error
);
Sets a filter among the rows presented by proxy
. The filter is defined by a filter expression
which can be any SQL valid expression using proxy
's columns. For instance if proxy
has the "id" and
"name" columns, then a filter can be "length(name) < 5" to filter only the rows where the length of the
name is strictly inferior to 5, or "id >= 1000 and id < 2000 order by name limit 50" to filter only the rows where the id
is between 1000 and 2000, ordered by name and limited to 50 rows.
Note that any previous filter expression is replaced with the new filter_expr
if no error occurs
(if an error occurs, then any previous filter is left unchanged).
proxy |
a GdaDataProxy object |
|
filter_expr |
an SQL based expression which will filter the contents of |
|
error |
a place to store errors, or |
const gchar *
gda_data_proxy_get_filter_expr (GdaDataProxy *proxy
);
Get the current filter expression used by proxy
.
gint
gda_data_proxy_get_filtered_n_rows (GdaDataProxy *proxy
);
Get the total number of filtered rows in proxy
if a filter has been applied. As new rows
(rows added to the proxy and not yet added to the proxied data model) and rows to remove
(rows marked for removal but not yet removed from the proxied data model) are also filtered,
the returned number also contains reefrences to new rows and rows to be removed.
typedef struct { GdaObjectClass parent_class; void (* row_delete_changed) (GdaDataProxy *proxy, gint row, gboolean to_be_deleted); void (* sample_size_changed) (GdaDataProxy *proxy, gint sample_size); void (* sample_changed) (GdaDataProxy *proxy, gint sample_start, gint sample_end); gboolean (* pre_changes_applied) (GdaDataProxy *proxy, gint row, gint proxied_row); void (* post_changes_applied) (GdaDataProxy *proxy, gint row, gint proxied_row); } GdaDataProxyClass;
“prepend-null-entry”
property “prepend-null-entry” gboolean
Flags: Read / Write
Default value: FALSE
“filter-changed”
signalvoid user_function (GdaDataProxy *gdadataproxy, gpointer user_data)
gdadataproxy |
the object which received the signal. |
|
user_data |
user data set when the signal handler was connected. |
Flags: Run First
“post-changes-applied”
signalvoid user_function (GdaDataProxy *gdadataproxy, gint arg1, gint arg2, gpointer user_data)
gdadataproxy |
the object which received the signal. |
|
user_data |
user data set when the signal handler was connected. |
Flags: Run First
“pre-changes-applied”
signalgboolean user_function (GdaDataProxy *gdadataproxy, gint arg1, gint arg2, gpointer user_data)
gdadataproxy |
the object which received the signal. |
|
user_data |
user data set when the signal handler was connected. |
Flags: Run Last
“row-delete-changed”
signalvoid user_function (GdaDataProxy *gdadataproxy, gint arg1, gboolean arg2, gpointer user_data)
gdadataproxy |
the object which received the signal. |
|
user_data |
user data set when the signal handler was connected. |
Flags: Run First
“sample-changed”
signalvoid user_function (GdaDataProxy *gdadataproxy, gint arg1, gint arg2, gpointer user_data)
gdadataproxy |
the object which received the signal. |
|
user_data |
user data set when the signal handler was connected. |
Flags: Run First
“sample-size-changed”
signalvoid user_function (GdaDataProxy *gdadataproxy, gint arg1, gpointer user_data)
gdadataproxy |
the object which received the signal. |
|
user_data |
user data set when the signal handler was connected. |
Flags: Run First