1 /* 2 * Copyright (C) 2006 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef SkEvent_DEFINED 18 #define SkEvent_DEFINED 19 20 #include "SkDOM.h" 21 #include "SkMetaData.h" 22 #include "SkString.h" 23 24 /** Unique 32bit id used to identify an instance of SkEventSink. When events are 25 posted, they are posted to a specific sinkID. When it is time to dispatch the 26 event, the sinkID is used to find the specific SkEventSink object. If it is found, 27 its doEvent() method is called with the event. 28 */ 29 typedef uint32_t SkEventSinkID; 30 31 /** \class SkEvent 32 33 SkEvents are used to communicate type-safe information to SkEventSinks. 34 SkEventSinks (including SkViews) each have a unique ID, which is stored 35 in an event. This ID is used to target the event once it has been "posted". 36 */ 37 class SkEvent { 38 public: 39 /** Default construct, creating an empty event. 40 */ 41 SkEvent(); 42 /** Construct a new event with the specified type. 43 */ 44 explicit SkEvent(const SkString& type); 45 /** Construct a new event with the specified type. 46 */ 47 explicit SkEvent(const char type[]); 48 /** Construct a new event by copying the fields from the src event. 49 */ 50 SkEvent(const SkEvent& src); 51 ~SkEvent(); 52 53 // /** Return the event's type (will never be null) */ 54 // const char* getType() const; 55 /** Copy the event's type into the specified SkString parameter */ 56 void getType(SkString* str) const; 57 /** Returns true if the event's type matches exactly the specified type (case sensitive) */ 58 bool isType(const SkString& str) const; 59 /** Returns true if the event's type matches exactly the specified type (case sensitive) */ 60 bool isType(const char type[], size_t len = 0) const; 61 /** Set the event's type to the specified string. 62 In XML, use the "type" attribute. 63 */ 64 void setType(const SkString&); 65 /** Set the event's type to the specified string. 66 In XML, use the "type" attribute. 67 */ 68 void setType(const char type[], size_t len = 0); 69 70 /** Return the event's unnamed 32bit field. Default value is 0 */ 71 uint32_t getFast32() const { return f32; } 72 /** Set the event's unnamed 32bit field. In XML, use 73 the subelement <data fast32=... /> 74 */ 75 void setFast32(uint32_t x) { f32 = x; } 76 77 /** Return true if the event contains the named 32bit field, and return the field 78 in value (if value is non-null). If there is no matching named field, return false 79 and ignore the value parameter. 80 */ 81 bool findS32(const char name[], int32_t* value = NULL) const { return fMeta.findS32(name, value); } 82 /** Return true if the event contains the named SkScalar field, and return the field 83 in value (if value is non-null). If there is no matching named field, return false 84 and ignore the value parameter. 85 */ 86 bool findScalar(const char name[], SkScalar* value = NULL) const { return fMeta.findScalar(name, value); } 87 /** Return true if the event contains the named SkScalar field, and return the fields 88 in value[] (if value is non-null), and return the number of SkScalars in count (if count is non-null). 89 If there is no matching named field, return false and ignore the value and count parameters. 90 */ 91 const SkScalar* findScalars(const char name[], int* count, SkScalar values[] = NULL) const { return fMeta.findScalars(name, count, values); } 92 /** Return the value of the named string field, or if no matching named field exists, return null. 93 */ 94 const char* findString(const char name[]) const { return fMeta.findString(name); } 95 /** Return true if the event contains the named pointer field, and return the field 96 in value (if value is non-null). If there is no matching named field, return false 97 and ignore the value parameter. 98 */ 99 bool findPtr(const char name[], void** value) const { return fMeta.findPtr(name, value); } 100 bool findBool(const char name[], bool* value) const { return fMeta.findBool(name, value); } 101 const void* findData(const char name[], size_t* byteCount = NULL) const { 102 return fMeta.findData(name, byteCount); 103 } 104 105 /** Returns true if ethe event contains the named 32bit field, and if it equals the specified value */ 106 bool hasS32(const char name[], int32_t value) const { return fMeta.hasS32(name, value); } 107 /** Returns true if ethe event contains the named SkScalar field, and if it equals the specified value */ 108 bool hasScalar(const char name[], SkScalar value) const { return fMeta.hasScalar(name, value); } 109 /** Returns true if ethe event contains the named string field, and if it equals (using strcmp) the specified value */ 110 bool hasString(const char name[], const char value[]) const { return fMeta.hasString(name, value); } 111 /** Returns true if ethe event contains the named pointer field, and if it equals the specified value */ 112 bool hasPtr(const char name[], void* value) const { return fMeta.hasPtr(name, value); } 113 bool hasBool(const char name[], bool value) const { return fMeta.hasBool(name, value); } 114 bool hasData(const char name[], const void* data, size_t byteCount) const { 115 return fMeta.hasData(name, data, byteCount); 116 } 117 118 /** Add/replace the named 32bit field to the event. In XML use the subelement <data name=... s32=... /> */ 119 void setS32(const char name[], int32_t value) { fMeta.setS32(name, value); } 120 /** Add/replace the named SkScalar field to the event. In XML use the subelement <data name=... scalar=... /> */ 121 void setScalar(const char name[], SkScalar value) { fMeta.setScalar(name, value); } 122 /** Add/replace the named SkScalar[] field to the event. */ 123 SkScalar* setScalars(const char name[], int count, const SkScalar values[] = NULL) { return fMeta.setScalars(name, count, values); } 124 /** Add/replace the named string field to the event. In XML use the subelement <data name=... string=... */ 125 void setString(const char name[], const SkString& value) { fMeta.setString(name, value.c_str()); } 126 /** Add/replace the named string field to the event. In XML use the subelement <data name=... string=... */ 127 void setString(const char name[], const char value[]) { fMeta.setString(name, value); } 128 /** Add/replace the named pointer field to the event. There is no XML equivalent for this call */ 129 void setPtr(const char name[], void* value) { fMeta.setPtr(name, value); } 130 void setBool(const char name[], bool value) { fMeta.setBool(name, value); } 131 void setData(const char name[], const void* data, size_t byteCount) { 132 fMeta.setData(name, data, byteCount); 133 } 134 135 /** Return the underlying metadata object */ 136 SkMetaData& getMetaData() { return fMeta; } 137 /** Return the underlying metadata object */ 138 const SkMetaData& getMetaData() const { return fMeta; } 139 140 void tron() { SkDEBUGCODE(fDebugTrace = true;) } 141 void troff() { SkDEBUGCODE(fDebugTrace = false;) } 142 bool isDebugTrace() const 143 { 144 #ifdef SK_DEBUG 145 return fDebugTrace; 146 #else 147 return false; 148 #endif 149 } 150 151 /** Call this to initialize the event from the specified XML node */ 152 void inflate(const SkDOM&, const SkDOM::Node*); 153 154 SkDEBUGCODE(void dump(const char title[] = NULL);) 155 156 /** Post the specified event to the event queue, targeting the specified eventsink, with an optional 157 delay. The event must be dynamically allocated for this. It cannot be a global or on the stack. 158 After this call, ownership is transfered to the system, so the caller must not retain 159 the event's ptr. Returns false if the event could not be posted (which means it will have been deleted). 160 */ 161 static bool Post(SkEvent* evt, SkEventSinkID targetID, SkMSec delay = 0); 162 /** Post the specified event to the event queue, targeting the specified eventsink, to be delivered on/after the 163 specified millisecond time. The event must be dynamically allocated for this. It cannot be a global or on the stack. 164 After this call, ownership is transfered to the system, so the caller must not retain 165 the event's ptr. Returns false if the event could not be posted (which means it will have been deleted). 166 */ 167 static bool PostTime(SkEvent* evt, SkEventSinkID targetID, SkMSec time); 168 169 /** Helper method for calling SkEvent::PostTime(this, ...), where the caller specifies a delay. 170 The real "time" will be computed automatically by sampling the clock and adding its value 171 to delay. 172 */ 173 bool post(SkEventSinkID sinkID, SkMSec delay = 0) 174 { 175 return SkEvent::Post(this, sinkID, delay); 176 } 177 178 void postTime(SkEventSinkID sinkID, SkMSec time) 179 { 180 SkEvent::PostTime(this, sinkID, time); 181 } 182 183 /////////////////////////////////////////////// 184 /** Porting layer must call these functions **/ 185 /////////////////////////////////////////////// 186 187 /** Global initialization function for the SkEvent system. Should be called exactly 188 once before any other event method is called, and should be called after the 189 call to SkGraphics::Init(). 190 */ 191 static void Init(); 192 /** Global cleanup function for the SkEvent system. Should be called exactly once after 193 all event methods have been called, and should be called before calling SkGraphics::Term(). 194 */ 195 static void Term(); 196 197 /** Call this to process one event from the queue. If it returns true, there are more events 198 to process. 199 */ 200 static bool ProcessEvent(); 201 /** Call this whenever the requested timer has expired (requested by a call to SetQueueTimer). 202 It will post any delayed events whose time as "expired" onto the event queue. 203 It may also call SignalQueueTimer() and SignalNonEmptyQueue(). 204 */ 205 static void ServiceQueueTimer(); 206 207 /** Return the number of queued events. note that this value may be obsolete 208 upon return, since another thread may have called ProcessEvent() or 209 Post() after the count was made. 210 */ 211 static int CountEventsOnQueue(); 212 213 //////////////////////////////////////////////////// 214 /** Porting layer must implement these functions **/ 215 //////////////////////////////////////////////////// 216 217 /** Called whenever an SkEvent is posted to an empty queue, so that the OS 218 can be told to later call Dequeue(). 219 */ 220 static void SignalNonEmptyQueue(); 221 /** Called whenever the delay until the next delayed event changes. If zero is 222 passed, then there are no more queued delay events. 223 */ 224 static void SignalQueueTimer(SkMSec delay); 225 226 #ifndef SK_USE_WXWIDGETS 227 #ifdef SK_BUILD_FOR_WIN 228 static bool WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam); 229 #elif defined(SK_BUILD_FOR_UNIXx) 230 static uint32_t HandleTimer(uint32_t, void*); 231 static bool WndProc(Display*, Window, XEvent&); 232 #endif 233 #else 234 // Don't know yet what this will be 235 //static bool CustomEvent(); 236 #endif 237 238 private: 239 SkMetaData fMeta; 240 mutable char* fType; // may be characters with low bit set to know that it is not a pointer 241 uint32_t f32; 242 SkDEBUGCODE(bool fDebugTrace;) 243 244 // these are for our implementation of the event queue 245 SkEventSinkID fTargetID; 246 SkMSec fTime; 247 SkEvent* fNextEvent; // either in the delay or normal event queue 248 void initialize(const char* type, size_t typeLen); 249 250 static bool Enqueue(SkEvent* evt); 251 static SkMSec EnqueueTime(SkEvent* evt, SkMSec time); 252 static SkEvent* Dequeue(SkEventSinkID* targetID); 253 static bool QHasEvents(); 254 }; 255 256 #endif 257 258