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fl_mouse_cursor_handler.cc
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1 // Copyright 2013 The Flutter Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "flutter/shell/platform/linux/fl_mouse_cursor_handler.h"
6
7 #include <gtk/gtk.h>
8 #include <cstring>
9
10 #include "flutter/shell/platform/linux/public/flutter_linux/fl_method_channel.h"
11 #include "flutter/shell/platform/linux/public/flutter_linux/fl_standard_method_codec.h"
12
13 static constexpr char kChannelName[] = "flutter/mousecursor";
14 static constexpr char kBadArgumentsError[] = "Bad Arguments";
15 static constexpr char kActivateSystemCursorMethod[] = "activateSystemCursor";
16 static constexpr char kKindKey[] = "kind";
17
18 static constexpr char kFallbackCursor[] = "default";
19
20 struct _FlMouseCursorHandler {
21 GObject parent_instance;
22
23 FlMethodChannel* channel;
24
25 FlView* view;
26
27 GHashTable* system_cursor_table;
28 };
29
30 G_DEFINE_TYPE(FlMouseCursorHandler, fl_mouse_cursor_handler, G_TYPE_OBJECT)
31
32 // Insert a new entry into a hashtable from strings to strings.
33 //
34 // Returns whether the newly added value was already in the hash table or not.
35 static bool define_system_cursor(GHashTable* table,
36 const gchar* key,
37 const gchar* value) {
38 return g_hash_table_insert(
39 table, reinterpret_cast<gpointer>(const_cast<gchar*>(key)),
40 reinterpret_cast<gpointer>(const_cast<gchar*>(value)));
41 }
42
43 // Populate the hash table so that it maps from Flutter's cursor kinds to GTK's
44 // cursor values.
45 //
46 // The table must have been created as a hashtable from strings to strings.
47 static void populate_system_cursor_table(GHashTable* table) {
48 // The following mapping must be kept in sync with Flutter framework's
49 // mouse_cursor.dart.
50 define_system_cursor(table, "alias", "alias");
51 define_system_cursor(table, "allScroll", "all-scroll");
52 define_system_cursor(table, "basic", "default");
53 define_system_cursor(table, "cell", "cell");
54 define_system_cursor(table, "click", "pointer");
55 define_system_cursor(table, "contextMenu", "context-menu");
56 define_system_cursor(table, "copy", "copy");
57 define_system_cursor(table, "forbidden", "not-allowed");
58 define_system_cursor(table, "grab", "grab");
59 define_system_cursor(table, "grabbing", "grabbing");
60 define_system_cursor(table, "help", "help");
61 define_system_cursor(table, "move", "move");
62 define_system_cursor(table, "none", "none");
63 define_system_cursor(table, "noDrop", "no-drop");
64 define_system_cursor(table, "precise", "crosshair");
65 define_system_cursor(table, "progress", "progress");
66 define_system_cursor(table, "text", "text");
67 define_system_cursor(table, "resizeColumn", "col-resize");
68 define_system_cursor(table, "resizeDown", "s-resize");
69 define_system_cursor(table, "resizeDownLeft", "sw-resize");
70 define_system_cursor(table, "resizeDownRight", "se-resize");
71 define_system_cursor(table, "resizeLeft", "w-resize");
72 define_system_cursor(table, "resizeLeftRight", "ew-resize");
73 define_system_cursor(table, "resizeRight", "e-resize");
74 define_system_cursor(table, "resizeRow", "row-resize");
75 define_system_cursor(table, "resizeUp", "n-resize");
76 define_system_cursor(table, "resizeUpDown", "ns-resize");
77 define_system_cursor(table, "resizeUpLeft", "nw-resize");
78 define_system_cursor(table, "resizeUpRight", "ne-resize");
79 define_system_cursor(table, "resizeUpLeftDownRight", "nwse-resize");
80 define_system_cursor(table, "resizeUpRightDownLeft", "nesw-resize");
81 define_system_cursor(table, "verticalText", "vertical-text");
82 define_system_cursor(table, "wait", "wait");
83 define_system_cursor(table, "zoomIn", "zoom-in");
84 define_system_cursor(table, "zoomOut", "zoom-out");
85 }
86
87 // Sets the mouse cursor.
88 FlMethodResponse* activate_system_cursor(FlMouseCursorHandler* self,
89 FlValue* args) {
90 if (fl_value_get_type(args) != FL_VALUE_TYPE_MAP) {
91 return FL_METHOD_RESPONSE(fl_method_error_response_new(
92 kBadArgumentsError, "Argument map missing or malformed", nullptr));
93 }
94
95 FlValue* kind_value = fl_value_lookup_string(args, kKindKey);
96 const gchar* kind = nullptr;
97 if (fl_value_get_type(kind_value) == FL_VALUE_TYPE_STRING) {
98 kind = fl_value_get_string(kind_value);
99 }
100
101 if (self->system_cursor_table == nullptr) {
102 self->system_cursor_table = g_hash_table_new(g_str_hash, g_str_equal);
103 populate_system_cursor_table(self->system_cursor_table);
104 }
105
106 const gchar* cursor_name = reinterpret_cast<const gchar*>(
107 g_hash_table_lookup(self->system_cursor_table, kind));
108 if (cursor_name == nullptr) {
109 cursor_name = kFallbackCursor;
110 }
111
112 GdkWindow* window =
113 gtk_widget_get_window(gtk_widget_get_toplevel(GTK_WIDGET(self->view)));
114 g_autoptr(GdkCursor) cursor =
115 gdk_cursor_new_from_name(gdk_window_get_display(window), cursor_name);
116 gdk_window_set_cursor(window, cursor);
117
118 return FL_METHOD_RESPONSE(fl_method_success_response_new(nullptr));
119 }
120
121 // Called when a method call is received from Flutter.
122 static void method_call_cb(FlMethodChannel* channel,
123 FlMethodCall* method_call,
124 gpointer user_data) {
125 FlMouseCursorHandler* self = FL_MOUSE_CURSOR_HANDLER(user_data);
126
127 const gchar* method = fl_method_call_get_name(method_call);
128 FlValue* args = fl_method_call_get_args(method_call);
129
130 g_autoptr(FlMethodResponse) response = nullptr;
131 if (strcmp(method, kActivateSystemCursorMethod) == 0) {
132 response = activate_system_cursor(self, args);
133 } else {
134 response = FL_METHOD_RESPONSE(fl_method_not_implemented_response_new());
135 }
136
137 g_autoptr(GError) error = nullptr;
138 if (!fl_method_call_respond(method_call, response, &error)) {
139 g_warning("Failed to send method call response: %s", error->message);
140 }
141 }
142
143 static void fl_mouse_cursor_handler_dispose(GObject* object) {
144 FlMouseCursorHandler* self = FL_MOUSE_CURSOR_HANDLER(object);
145
146 g_clear_object(&self->channel);
147 if (self->view != nullptr) {
148 g_object_remove_weak_pointer(G_OBJECT(self->view),
149 reinterpret_cast<gpointer*>(&(self->view)));
150 self->view = nullptr;
151 }
152 g_clear_pointer(&self->system_cursor_table, g_hash_table_unref);
153
154 G_OBJECT_CLASS(fl_mouse_cursor_handler_parent_class)->dispose(object);
155 }
156
157 static void fl_mouse_cursor_handler_class_init(
158 FlMouseCursorHandlerClass* klass) {
159 G_OBJECT_CLASS(klass)->dispose = fl_mouse_cursor_handler_dispose;
160 }
161
162 static void fl_mouse_cursor_handler_init(FlMouseCursorHandler* self) {}
163
164 FlMouseCursorHandler* fl_mouse_cursor_handler_new(FlBinaryMessenger* messenger,
165 FlView* view) {
166 g_return_val_if_fail(FL_IS_BINARY_MESSENGER(messenger), nullptr);
167
168 FlMouseCursorHandler* self = FL_MOUSE_CURSOR_HANDLER(
169 g_object_new(fl_mouse_cursor_handler_get_type(), nullptr));
170
171 g_autoptr(FlStandardMethodCodec) codec = fl_standard_method_codec_new();
172 self->channel =
173 fl_method_channel_new(messenger, kChannelName, FL_METHOD_CODEC(codec));
174 fl_method_channel_set_method_call_handler(self->channel, method_call_cb, self,
175 nullptr);
176 self->view = view;
177 if (view != nullptr) {
178 g_object_add_weak_pointer(G_OBJECT(view),
179 reinterpret_cast<gpointer*>(&(self->view)));
180 }
181
182 return self;
183 }
FL_VALUE_TYPE_MAP
@ FL_VALUE_TYPE_MAP
Definition: fl_value.h:75
_FlMouseCursorHandler::system_cursor_table
GHashTable * system_cursor_table
Definition: fl_mouse_cursor_handler.cc:27
_FlMouseCursorHandler::parent_instance
GObject parent_instance
Definition: fl_mouse_cursor_handler.cc:21
kKindKey
static constexpr char kKindKey[]
Definition: fl_mouse_cursor_handler.cc:16
fl_method_channel_new
G_MODULE_EXPORT FlMethodChannel * fl_method_channel_new(FlBinaryMessenger *messenger, const gchar *name, FlMethodCodec *codec)
Definition: fl_method_channel.cc:112
fl_method_error_response_new
G_MODULE_EXPORT FlMethodErrorResponse * fl_method_error_response_new(const gchar *code, const gchar *message, FlValue *details)
Definition: fl_method_response.cc:144
fl_method_not_implemented_response_new
G_MODULE_EXPORT FlMethodNotImplementedResponse * fl_method_not_implemented_response_new()
Definition: fl_method_response.cc:179
fl_standard_method_codec_new
G_MODULE_EXPORT FlStandardMethodCodec * fl_standard_method_codec_new()
Definition: fl_standard_method_codec.cc:291
kActivateSystemCursorMethod
static constexpr char kActivateSystemCursorMethod[]
Definition: fl_mouse_cursor_handler.cc:15
fl_method_channel.h
FlValue
typedefG_BEGIN_DECLS struct _FlValue FlValue
Definition: fl_value.h:42
user_data
FlKeyEvent uint64_t FlKeyResponderAsyncCallback gpointer user_data
Definition: fl_key_channel_responder.cc:121
fl_mouse_cursor_handler_dispose
static void fl_mouse_cursor_handler_dispose(GObject *object)
Definition: fl_mouse_cursor_handler.cc:143
fl_value_lookup_string
G_MODULE_EXPORT FlValue * fl_value_lookup_string(FlValue *self, const gchar *key)
Definition: fl_value.cc:811
define_system_cursor
static bool define_system_cursor(GHashTable *table, const gchar *key, const gchar *value)
Definition: fl_mouse_cursor_handler.cc:35
fl_value_get_string
const G_MODULE_EXPORT gchar * fl_value_get_string(FlValue *self)
Definition: fl_value.cc:682
fl_mouse_cursor_handler_init
static void fl_mouse_cursor_handler_init(FlMouseCursorHandler *self)
Definition: fl_mouse_cursor_handler.cc:162
_FlMouseCursorHandler
Definition: fl_mouse_cursor_handler.cc:20
_FlMouseCursorHandler::channel
FlMethodChannel * channel
Definition: fl_mouse_cursor_handler.cc:23
fl_method_success_response_new
G_MODULE_EXPORT FlMethodSuccessResponse * fl_method_success_response_new(FlValue *result)
Definition: fl_method_response.cc:126
_FlMouseCursorHandler::view
FlView * view
Definition: fl_mouse_cursor_handler.cc:25
activate_system_cursor
FlMethodResponse * activate_system_cursor(FlMouseCursorHandler *self, FlValue *args)
Definition: fl_mouse_cursor_handler.cc:88
fl_method_call_respond
G_MODULE_EXPORT gboolean fl_method_call_respond(FlMethodCall *self, FlMethodResponse *response, GError **error)
Definition: fl_method_call.cc:77
fl_value_get_type
G_MODULE_EXPORT FlValueType fl_value_get_type(FlValue *self)
Definition: fl_value.cc:466
method_call
G_BEGIN_DECLS G_MODULE_EXPORT FlMethodCall * method_call
Definition: fl_method_channel.h:120
FL_VALUE_TYPE_STRING
@ FL_VALUE_TYPE_STRING
Definition: fl_value.h:69
fl_method_call_get_name
const G_MODULE_EXPORT gchar * fl_method_call_get_name(FlMethodCall *self)
Definition: fl_method_call.cc:67
fl_mouse_cursor_handler.h
G_DEFINE_TYPE
G_DEFINE_TYPE(FlBasicMessageChannelResponseHandle, fl_basic_message_channel_response_handle, G_TYPE_OBJECT) static void fl_basic_message_channel_response_handle_dispose(GObject *object)
Definition: fl_basic_message_channel.cc:37
method_call_cb
static void method_call_cb(FlMethodChannel *channel, FlMethodCall *method_call, gpointer user_data)
Definition: fl_mouse_cursor_handler.cc:122
fl_standard_method_codec.h
fl_method_channel_set_method_call_handler
G_MODULE_EXPORT void fl_method_channel_set_method_call_handler(FlMethodChannel *self, FlMethodChannelMethodCallHandler handler, gpointer user_data, GDestroyNotify destroy_notify)
Definition: fl_method_channel.cc:134
populate_system_cursor_table
static void populate_system_cursor_table(GHashTable *table)
Definition: fl_mouse_cursor_handler.cc:47
view
FlView * view
Definition: fl_application.cc:35
args
G_BEGIN_DECLS G_MODULE_EXPORT FlValue * args
Definition: fl_event_channel.h:89
error
const uint8_t uint32_t uint32_t GError ** error
Definition: fl_pixel_buffer_texture_test.cc:40
fl_mouse_cursor_handler_class_init
static void fl_mouse_cursor_handler_class_init(FlMouseCursorHandlerClass *klass)
Definition: fl_mouse_cursor_handler.cc:157
kBadArgumentsError
static constexpr char kBadArgumentsError[]
Definition: fl_mouse_cursor_handler.cc:14
fl_method_call_get_args
G_MODULE_EXPORT FlValue * fl_method_call_get_args(FlMethodCall *self)
Definition: fl_method_call.cc:72
kChannelName
static constexpr char kChannelName[]
Definition: fl_mouse_cursor_handler.cc:13
value
uint8_t value
Definition: fl_standard_message_codec.cc:36
fl_mouse_cursor_handler_new
FlMouseCursorHandler * fl_mouse_cursor_handler_new(FlBinaryMessenger *messenger, FlView *view)
Definition: fl_mouse_cursor_handler.cc:164
kFallbackCursor
static constexpr char kFallbackCursor[]
Definition: fl_mouse_cursor_handler.cc:18