1 /* 2 * This file is part of gtkD. 3 * 4 * gtkD is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU Lesser General Public License 6 * as published by the Free Software Foundation; either version 3 7 * of the License, or (at your option) any later version, with 8 * some exceptions, please read the COPYING file. 9 * 10 * gtkD is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU Lesser General Public License for more details. 14 * 15 * You should have received a copy of the GNU Lesser General Public License 16 * along with gtkD; if not, write to the Free Software 17 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110, USA 18 */ 19 20 // generated automatically - do not change 21 // find conversion definition on APILookup.txt 22 // implement new conversion functionalities on the wrap.utils pakage 23 24 25 module gio.AsyncResultT; 26 27 public import gio.c.functions; 28 public import gio.c.types; 29 public import glib.ErrorG; 30 public import glib.GException; 31 public import gobject.ObjectG; 32 33 34 /** 35 * Provides a base class for implementing asynchronous function results. 36 * 37 * Asynchronous operations are broken up into two separate operations 38 * which are chained together by a #GAsyncReadyCallback. To begin 39 * an asynchronous operation, provide a #GAsyncReadyCallback to the 40 * asynchronous function. This callback will be triggered when the 41 * operation has completed, and must be run in a later iteration of 42 * the [thread-default main context][g-main-context-push-thread-default] 43 * from where the operation was initiated. It will be passed a 44 * #GAsyncResult instance filled with the details of the operation's 45 * success or failure, the object the asynchronous function was 46 * started for and any error codes returned. The asynchronous callback 47 * function is then expected to call the corresponding "_finish()" 48 * function, passing the object the function was called for, the 49 * #GAsyncResult instance, and (optionally) an @error to grab any 50 * error conditions that may have occurred. 51 * 52 * The "_finish()" function for an operation takes the generic result 53 * (of type #GAsyncResult) and returns the specific result that the 54 * operation in question yields (e.g. a #GFileEnumerator for a 55 * "enumerate children" operation). If the result or error status of the 56 * operation is not needed, there is no need to call the "_finish()" 57 * function; GIO will take care of cleaning up the result and error 58 * information after the #GAsyncReadyCallback returns. You can pass 59 * %NULL for the #GAsyncReadyCallback if you don't need to take any 60 * action at all after the operation completes. Applications may also 61 * take a reference to the #GAsyncResult and call "_finish()" later; 62 * however, the "_finish()" function may be called at most once. 63 * 64 * Example of a typical asynchronous operation flow: 65 * |[<!-- language="C" --> 66 * void _theoretical_frobnitz_async (Theoretical *t, 67 * GCancellable *c, 68 * GAsyncReadyCallback cb, 69 * gpointer u); 70 * 71 * gboolean _theoretical_frobnitz_finish (Theoretical *t, 72 * GAsyncResult *res, 73 * GError **e); 74 * 75 * static void 76 * frobnitz_result_func (GObject *source_object, 77 * GAsyncResult *res, 78 * gpointer user_data) 79 * { 80 * gboolean success = FALSE; 81 * 82 * success = _theoretical_frobnitz_finish (source_object, res, NULL); 83 * 84 * if (success) 85 * g_printf ("Hurray!\n"); 86 * else 87 * g_printf ("Uh oh!\n"); 88 * 89 * ... 90 * 91 * } 92 * 93 * int main (int argc, void *argv[]) 94 * { 95 * ... 96 * 97 * _theoretical_frobnitz_async (theoretical_data, 98 * NULL, 99 * frobnitz_result_func, 100 * NULL); 101 * 102 * ... 103 * } 104 * ]| 105 * 106 * The callback for an asynchronous operation is called only once, and is 107 * always called, even in the case of a cancelled operation. On cancellation 108 * the result is a %G_IO_ERROR_CANCELLED error. 109 * 110 * ## I/O Priority # {#io-priority} 111 * 112 * Many I/O-related asynchronous operations have a priority parameter, 113 * which is used in certain cases to determine the order in which 114 * operations are executed. They are not used to determine system-wide 115 * I/O scheduling. Priorities are integers, with lower numbers indicating 116 * higher priority. It is recommended to choose priorities between 117 * %G_PRIORITY_LOW and %G_PRIORITY_HIGH, with %G_PRIORITY_DEFAULT 118 * as a default. 119 */ 120 public template AsyncResultT(TStruct) 121 { 122 /** Get the main Gtk struct */ 123 public GAsyncResult* getAsyncResultStruct(bool transferOwnership = false) 124 { 125 if (transferOwnership) 126 ownedRef = false; 127 return cast(GAsyncResult*)getStruct(); 128 } 129 130 131 /** 132 * Gets the source object from a #GAsyncResult. 133 * 134 * Returns: a new reference to the source 135 * object for the @res, or %NULL if there is none. 136 */ 137 public ObjectG getSourceObject() 138 { 139 auto __p = g_async_result_get_source_object(getAsyncResultStruct()); 140 141 if(__p is null) 142 { 143 return null; 144 } 145 146 return ObjectG.getDObject!(ObjectG)(cast(GObject*) __p, true); 147 } 148 149 /** 150 * Gets the user data from a #GAsyncResult. 151 * 152 * Returns: the user data for @res. 153 */ 154 public void* getUserData() 155 { 156 return g_async_result_get_user_data(getAsyncResultStruct()); 157 } 158 159 /** 160 * Checks if @res has the given @source_tag (generally a function 161 * pointer indicating the function @res was created by). 162 * 163 * Params: 164 * sourceTag = an application-defined tag 165 * 166 * Returns: %TRUE if @res has the indicated @source_tag, %FALSE if 167 * not. 168 * 169 * Since: 2.34 170 */ 171 public bool isTagged(void* sourceTag) 172 { 173 return g_async_result_is_tagged(getAsyncResultStruct(), sourceTag) != 0; 174 } 175 176 /** 177 * If @res is a #GSimpleAsyncResult, this is equivalent to 178 * g_simple_async_result_propagate_error(). Otherwise it returns 179 * %FALSE. 180 * 181 * This can be used for legacy error handling in async *_finish() 182 * wrapper functions that traditionally handled #GSimpleAsyncResult 183 * error returns themselves rather than calling into the virtual method. 184 * This should not be used in new code; #GAsyncResult errors that are 185 * set by virtual methods should also be extracted by virtual methods, 186 * to enable subclasses to chain up correctly. 187 * 188 * Returns: %TRUE if @error is has been filled in with an error from 189 * @res, %FALSE if not. 190 * 191 * Since: 2.34 192 * 193 * Throws: GException on failure. 194 */ 195 public bool legacyPropagateError() 196 { 197 GError* err = null; 198 199 auto __p = g_async_result_legacy_propagate_error(getAsyncResultStruct(), &err) != 0; 200 201 if (err !is null) 202 { 203 throw new GException( new ErrorG(err) ); 204 } 205 206 return __p; 207 } 208 }