shell/platform/linux/fl_text_input_plugin.cc - external/github.com/flutter/engine - Git at Google

 // Copyright 2013 The Flutter Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 #include "flutter/shell/platform/linux/fl_text_input_plugin.h"

 #include "flutter/shell/platform/common/cpp/text_input_model.h"
 #include "flutter/shell/platform/linux/public/flutter_linux/fl_json_method_codec.h"
 #include "flutter/shell/platform/linux/public/flutter_linux/fl_method_channel.h"

 #include <gtk/gtk.h>

 static constexpr char kChannelName[] = "flutter/textinput";

 static constexpr char kSetClientMethod[] = "TextInput.setClient";
 static constexpr char kShowMethod[] = "TextInput.show";
 static constexpr char kSetEditingStateMethod[] = "TextInput.setEditingState";
 static constexpr char kClearClientMethod[] = "TextInput.clearClient";
 static constexpr char kHideMethod[] = "TextInput.hide";
 static constexpr char kUpdateEditingStateMethod[] =
     "TextInputClient.updateEditingState";
 static constexpr char kPerformActionMethod[] = "TextInputClient.performAction";

 static constexpr char kInputActionKey[] = "inputAction";
 static constexpr char kTextKey[] = "text";
 static constexpr char kSelectionBaseKey[] = "selectionBase";
 static constexpr char kSelectionExtentKey[] = "selectionExtent";
 static constexpr char kSelectionAffinityKey[] = "selectionAffinity";
 static constexpr char kSelectionIsDirectionalKey[] = "selectionIsDirectional";
 static constexpr char kComposingBaseKey[] = "composingBase";
 static constexpr char kComposingExtentKey[] = "composingExtent";

 static constexpr char kTextAffinityDownstream[] = "TextAffinity.downstream";

 static constexpr int64_t kClientIdUnset = -1;

 struct _FlTextInputPlugin {
   GObject parent_instance;

   FlMethodChannel* channel;

   // Client ID provided by Flutter to report events with.
   int64_t client_id;

   // Input action to perform when enter pressed.
   gchar* input_action;

   // Input method.
   GtkIMContext* im_context;

   flutter::TextInputModel* text_model;
 };

 G_DEFINE_TYPE(FlTextInputPlugin, fl_text_input_plugin, G_TYPE_OBJECT)

 // Completes method call and returns TRUE if the call was successful.
 static gboolean finish_method(GObject* object,
                               GAsyncResult* result,
                               GError** error) {
   g_autoptr(FlMethodResponse) response = fl_method_channel_invoke_method_finish(
       FL_METHOD_CHANNEL(object), result, error);
   if (response == nullptr)
     return FALSE;
   return fl_method_response_get_result(response, error) != nullptr;
 }

 // Called when a response is received from TextInputClient.updateEditingState()
 static void update_editing_state_response_cb(GObject* object,
                                              GAsyncResult* result,
                                              gpointer user_data) {
   g_autoptr(GError) error = nullptr;
   if (!finish_method(object, result, &error)) {
     g_warning("Failed to call %s: %s", kUpdateEditingStateMethod,
               error->message);
   }
 }

 // Informs Flutter of text input changes.
 static void update_editing_state(FlTextInputPlugin* self) {
   g_autoptr(FlValue) args = fl_value_new_list();
   fl_value_append_take(args, fl_value_new_int(self->client_id));
   g_autoptr(FlValue) value = fl_value_new_map();

   fl_value_set_string_take(
       value, kTextKey,
       fl_value_new_string(self->text_model->GetText().c_str()));
   fl_value_set_string_take(
       value, kSelectionBaseKey,
       fl_value_new_int(self->text_model->selection_base()));
   fl_value_set_string_take(
       value, kSelectionExtentKey,
       fl_value_new_int(self->text_model->selection_extent()));

   // The following keys are not implemented and set to default values.
   fl_value_set_string_take(value, kSelectionAffinityKey,
                            fl_value_new_string(kTextAffinityDownstream));
   fl_value_set_string_take(value, kSelectionIsDirectionalKey,
                            fl_value_new_bool(FALSE));
   fl_value_set_string_take(value, kComposingBaseKey, fl_value_new_int(-1));
   fl_value_set_string_take(value, kComposingExtentKey, fl_value_new_int(-1));

   fl_value_append(args, value);

   fl_method_channel_invoke_method(self->channel, kUpdateEditingStateMethod,
                                   args, nullptr,
                                   update_editing_state_response_cb, self);
 }

 // Called when a response is received from TextInputClient.performAction()
 static void perform_action_response_cb(GObject* object,
                                        GAsyncResult* result,
                                        gpointer user_data) {
   g_autoptr(GError) error = nullptr;
   if (!finish_method(object, result, &error))
     g_warning("Failed to call %s: %s", kPerformActionMethod, error->message);
 }

 // Inform Flutter that the input has been activated.
 static void perform_action(FlTextInputPlugin* self) {
   g_return_if_fail(FL_IS_TEXT_INPUT_PLUGIN(self));
   g_return_if_fail(self->client_id != 0);
   g_return_if_fail(self->input_action != nullptr);

   g_autoptr(FlValue) args = fl_value_new_list();
   fl_value_append_take(args, fl_value_new_int(self->client_id));
   fl_value_append_take(args, fl_value_new_string(self->input_action));

   fl_method_channel_invoke_method(self->channel, kPerformActionMethod, args,
                                   nullptr, perform_action_response_cb, self);
 }

 // Signal handler for GtkIMContext::commit
 static void im_commit_cb(FlTextInputPlugin* self, const gchar* text) {
   self->text_model->AddText(text);
   update_editing_state(self);
 }

 // Signal handler for GtkIMContext::retrieve-surrounding
 static gboolean im_retrieve_surrounding_cb(FlTextInputPlugin* self) {
   auto text = self->text_model->GetText();
   size_t cursor_offset = self->text_model->GetCursorOffset();
   gtk_im_context_set_surrounding(self->im_context, text.c_str(), -1,
                                  cursor_offset);
   return TRUE;
 }

 // Signal handler for GtkIMContext::delete-surrounding
 static gboolean im_delete_surrounding_cb(FlTextInputPlugin* self,
                                          gint offset,
                                          gint n_chars) {
   if (self->text_model->DeleteSurrounding(offset, n_chars))
     update_editing_state(self);
   return TRUE;
 }

 // Called when a method call is received from Flutter.
 static void method_call_cb(FlMethodChannel* channel,
                            FlMethodCall* method_call,
                            gpointer user_data) {
   FlTextInputPlugin* self = FL_TEXT_INPUT_PLUGIN(user_data);

   const gchar* method = fl_method_call_get_name(method_call);
   FlValue* args = fl_method_call_get_args(method_call);

   if (strcmp(method, kSetClientMethod) == 0) {
     self->client_id = fl_value_get_int(fl_value_get_list_value(args, 0));
     FlValue* config_value = fl_value_get_list_value(args, 1);
     g_free(self->input_action);
     FlValue* input_action_value =
         fl_value_lookup_string(config_value, kInputActionKey);
     if (fl_value_get_type(input_action_value) == FL_VALUE_TYPE_STRING)
       self->input_action = g_strdup(fl_value_get_string(input_action_value));
     fl_method_call_respond_success(method_call, nullptr, nullptr);
   } else if (strcmp(method, kShowMethod) == 0) {
     gtk_im_context_focus_in(self->im_context);
     fl_method_call_respond_success(method_call, nullptr, nullptr);
   } else if (strcmp(method, kSetEditingStateMethod) == 0) {
     const gchar* text =
         fl_value_get_string(fl_value_lookup_string(args, kTextKey));
     int64_t selection_base =
         fl_value_get_int(fl_value_lookup_string(args, kSelectionBaseKey));
     int64_t selection_extent =
         fl_value_get_int(fl_value_lookup_string(args, kSelectionExtentKey));

     self->text_model->SetEditingState(selection_base, selection_extent, text);

     fl_method_call_respond_success(method_call, nullptr, nullptr);
   } else if (strcmp(method, kClearClientMethod) == 0) {
     self->client_id = kClientIdUnset;
     fl_method_call_respond_success(method_call, nullptr, nullptr);
   } else if (strcmp(method, kHideMethod) == 0) {
     gtk_im_context_focus_out(self->im_context);
     fl_method_call_respond_success(method_call, nullptr, nullptr);
   } else
     fl_method_call_respond_not_implemented(method_call, nullptr);
 }

 static void fl_text_input_plugin_dispose(GObject* object) {
   FlTextInputPlugin* self = FL_TEXT_INPUT_PLUGIN(object);

   g_clear_object(&self->channel);
   g_clear_pointer(&self->input_action, g_free);
   g_clear_object(&self->im_context);
   if (self->text_model != nullptr) {
     delete self->text_model;
     self->text_model = nullptr;
   }

   G_OBJECT_CLASS(fl_text_input_plugin_parent_class)->dispose(object);
 }

 static void fl_text_input_plugin_class_init(FlTextInputPluginClass* klass) {
   G_OBJECT_CLASS(klass)->dispose = fl_text_input_plugin_dispose;
 }

 static void fl_text_input_plugin_init(FlTextInputPlugin* self) {
   self->client_id = kClientIdUnset;
   self->im_context = gtk_im_multicontext_new();
   g_signal_connect_object(self->im_context, "commit", G_CALLBACK(im_commit_cb),
                           self, G_CONNECT_SWAPPED);
   g_signal_connect_object(self->im_context, "retrieve-surrounding",
                           G_CALLBACK(im_retrieve_surrounding_cb), self,
                           G_CONNECT_SWAPPED);
   g_signal_connect_object(self->im_context, "delete-surrounding",
                           G_CALLBACK(im_delete_surrounding_cb), self,
                           G_CONNECT_SWAPPED);
   self->text_model = new flutter::TextInputModel("", "");
 }

 FlTextInputPlugin* fl_text_input_plugin_new(FlBinaryMessenger* messenger) {
   g_return_val_if_fail(FL_IS_BINARY_MESSENGER(messenger), nullptr);

   FlTextInputPlugin* self = FL_TEXT_INPUT_PLUGIN(
       g_object_new(fl_text_input_plugin_get_type(), nullptr));

   g_autoptr(FlJsonMethodCodec) codec = fl_json_method_codec_new();
   self->channel =
       fl_method_channel_new(messenger, kChannelName, FL_METHOD_CODEC(codec));
   fl_method_channel_set_method_call_handler(self->channel, method_call_cb, self,
                                             nullptr);

   return self;
 }

 gboolean fl_text_input_plugin_filter_keypress(FlTextInputPlugin* self,
                                               GdkEventKey* event) {
   g_return_val_if_fail(FL_IS_TEXT_INPUT_PLUGIN(self), FALSE);
   if (gtk_im_context_filter_keypress(self->im_context, event))
     return TRUE;

   // Handle navigation keys.
   gboolean changed = FALSE;
   if (event->type == GDK_KEY_PRESS) {
     switch (event->keyval) {
       case GDK_KEY_BackSpace:
         changed = self->text_model->Backspace();
         break;
       case GDK_KEY_Delete:
       case GDK_KEY_KP_Delete:
         // Already handled inside Flutter.
         break;
       case GDK_KEY_End:
       case GDK_KEY_KP_End:
         changed = self->text_model->MoveCursorToEnd();
         break;
       case GDK_KEY_Return:
       case GDK_KEY_KP_Enter:
       case GDK_KEY_ISO_Enter:
         perform_action(self);
         break;
       case GDK_KEY_Home:
       case GDK_KEY_KP_Home:
         changed = self->text_model->MoveCursorToBeginning();
         break;
       case GDK_KEY_Left:
       case GDK_KEY_KP_Left:
         // Already handled inside Flutter.
         break;
       case GDK_KEY_Right:
       case GDK_KEY_KP_Right:
         // Already handled inside Flutter.
         break;
     }
   }

   if (changed)
     update_editing_state(self);

   return FALSE;
 }
	// Copyright 2013 The Flutter Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	#include "flutter/shell/platform/linux/fl_text_input_plugin.h"

	#include "flutter/shell/platform/common/cpp/text_input_model.h"
	#include "flutter/shell/platform/linux/public/flutter_linux/fl_json_method_codec.h"
	#include "flutter/shell/platform/linux/public/flutter_linux/fl_method_channel.h"

	#include <gtk/gtk.h>

	static constexpr char kChannelName[] = "flutter/textinput";

	static constexpr char kSetClientMethod[] = "TextInput.setClient";
	static constexpr char kShowMethod[] = "TextInput.show";
	static constexpr char kSetEditingStateMethod[] = "TextInput.setEditingState";
	static constexpr char kClearClientMethod[] = "TextInput.clearClient";
	static constexpr char kHideMethod[] = "TextInput.hide";
	static constexpr char kUpdateEditingStateMethod[] =
	"TextInputClient.updateEditingState";
	static constexpr char kPerformActionMethod[] = "TextInputClient.performAction";

	static constexpr char kInputActionKey[] = "inputAction";
	static constexpr char kTextKey[] = "text";
	static constexpr char kSelectionBaseKey[] = "selectionBase";
	static constexpr char kSelectionExtentKey[] = "selectionExtent";
	static constexpr char kSelectionAffinityKey[] = "selectionAffinity";
	static constexpr char kSelectionIsDirectionalKey[] = "selectionIsDirectional";
	static constexpr char kComposingBaseKey[] = "composingBase";
	static constexpr char kComposingExtentKey[] = "composingExtent";

	static constexpr char kTextAffinityDownstream[] = "TextAffinity.downstream";

	static constexpr int64_t kClientIdUnset = -1;

	struct _FlTextInputPlugin {
	GObject parent_instance;

	FlMethodChannel* channel;

	// Client ID provided by Flutter to report events with.
	int64_t client_id;

	// Input action to perform when enter pressed.
	gchar* input_action;

	// Input method.
	GtkIMContext* im_context;

	flutter::TextInputModel* text_model;
	};

	G_DEFINE_TYPE(FlTextInputPlugin, fl_text_input_plugin, G_TYPE_OBJECT)

	// Completes method call and returns TRUE if the call was successful.
	static gboolean finish_method(GObject* object,
	GAsyncResult* result,
	GError** error) {
	g_autoptr(FlMethodResponse) response = fl_method_channel_invoke_method_finish(
	FL_METHOD_CHANNEL(object), result, error);
	if (response == nullptr)
	return FALSE;
	return fl_method_response_get_result(response, error) != nullptr;
	}

	// Called when a response is received from TextInputClient.updateEditingState()
	static void update_editing_state_response_cb(GObject* object,
	GAsyncResult* result,
	gpointer user_data) {
	g_autoptr(GError) error = nullptr;
	if (!finish_method(object, result, &error)) {
	g_warning("Failed to call %s: %s", kUpdateEditingStateMethod,
	error->message);
	}
	}

	// Informs Flutter of text input changes.
	static void update_editing_state(FlTextInputPlugin* self) {
	g_autoptr(FlValue) args = fl_value_new_list();
	fl_value_append_take(args, fl_value_new_int(self->client_id));
	g_autoptr(FlValue) value = fl_value_new_map();

	fl_value_set_string_take(
	value, kTextKey,
	fl_value_new_string(self->text_model->GetText().c_str()));
	fl_value_set_string_take(
	value, kSelectionBaseKey,
	fl_value_new_int(self->text_model->selection_base()));
	fl_value_set_string_take(
	value, kSelectionExtentKey,
	fl_value_new_int(self->text_model->selection_extent()));

	// The following keys are not implemented and set to default values.
	fl_value_set_string_take(value, kSelectionAffinityKey,
	fl_value_new_string(kTextAffinityDownstream));
	fl_value_set_string_take(value, kSelectionIsDirectionalKey,
	fl_value_new_bool(FALSE));
	fl_value_set_string_take(value, kComposingBaseKey, fl_value_new_int(-1));
	fl_value_set_string_take(value, kComposingExtentKey, fl_value_new_int(-1));

	fl_value_append(args, value);

	fl_method_channel_invoke_method(self->channel, kUpdateEditingStateMethod,
	args, nullptr,
	update_editing_state_response_cb, self);
	}

	// Called when a response is received from TextInputClient.performAction()
	static void perform_action_response_cb(GObject* object,
	GAsyncResult* result,
	gpointer user_data) {
	g_autoptr(GError) error = nullptr;
	if (!finish_method(object, result, &error))
	g_warning("Failed to call %s: %s", kPerformActionMethod, error->message);
	}

	// Inform Flutter that the input has been activated.
	static void perform_action(FlTextInputPlugin* self) {
	g_return_if_fail(FL_IS_TEXT_INPUT_PLUGIN(self));
	g_return_if_fail(self->client_id != 0);
	g_return_if_fail(self->input_action != nullptr);

	g_autoptr(FlValue) args = fl_value_new_list();
	fl_value_append_take(args, fl_value_new_int(self->client_id));
	fl_value_append_take(args, fl_value_new_string(self->input_action));

	fl_method_channel_invoke_method(self->channel, kPerformActionMethod, args,
	nullptr, perform_action_response_cb, self);
	}

	// Signal handler for GtkIMContext::commit
	static void im_commit_cb(FlTextInputPlugin* self, const gchar* text) {
	self->text_model->AddText(text);
	update_editing_state(self);
	}

	// Signal handler for GtkIMContext::retrieve-surrounding
	static gboolean im_retrieve_surrounding_cb(FlTextInputPlugin* self) {
	auto text = self->text_model->GetText();
	size_t cursor_offset = self->text_model->GetCursorOffset();
	gtk_im_context_set_surrounding(self->im_context, text.c_str(), -1,
	cursor_offset);
	return TRUE;
	}

	// Signal handler for GtkIMContext::delete-surrounding
	static gboolean im_delete_surrounding_cb(FlTextInputPlugin* self,
	gint offset,
	gint n_chars) {
	if (self->text_model->DeleteSurrounding(offset, n_chars))
	update_editing_state(self);
	return TRUE;
	}

	// Called when a method call is received from Flutter.
	static void method_call_cb(FlMethodChannel* channel,
	FlMethodCall* method_call,
	gpointer user_data) {
	FlTextInputPlugin* self = FL_TEXT_INPUT_PLUGIN(user_data);

	const gchar* method = fl_method_call_get_name(method_call);
	FlValue* args = fl_method_call_get_args(method_call);

	if (strcmp(method, kSetClientMethod) == 0) {
	self->client_id = fl_value_get_int(fl_value_get_list_value(args, 0));
	FlValue* config_value = fl_value_get_list_value(args, 1);
	g_free(self->input_action);
	FlValue* input_action_value =
	fl_value_lookup_string(config_value, kInputActionKey);
	if (fl_value_get_type(input_action_value) == FL_VALUE_TYPE_STRING)
	self->input_action = g_strdup(fl_value_get_string(input_action_value));
	fl_method_call_respond_success(method_call, nullptr, nullptr);
	} else if (strcmp(method, kShowMethod) == 0) {
	gtk_im_context_focus_in(self->im_context);
	fl_method_call_respond_success(method_call, nullptr, nullptr);
	} else if (strcmp(method, kSetEditingStateMethod) == 0) {
	const gchar* text =
	fl_value_get_string(fl_value_lookup_string(args, kTextKey));
	int64_t selection_base =
	fl_value_get_int(fl_value_lookup_string(args, kSelectionBaseKey));
	int64_t selection_extent =
	fl_value_get_int(fl_value_lookup_string(args, kSelectionExtentKey));

	self->text_model->SetEditingState(selection_base, selection_extent, text);

	fl_method_call_respond_success(method_call, nullptr, nullptr);
	} else if (strcmp(method, kClearClientMethod) == 0) {
	self->client_id = kClientIdUnset;
	fl_method_call_respond_success(method_call, nullptr, nullptr);
	} else if (strcmp(method, kHideMethod) == 0) {
	gtk_im_context_focus_out(self->im_context);
	fl_method_call_respond_success(method_call, nullptr, nullptr);
	} else
	fl_method_call_respond_not_implemented(method_call, nullptr);
	}

	static void fl_text_input_plugin_dispose(GObject* object) {
	FlTextInputPlugin* self = FL_TEXT_INPUT_PLUGIN(object);

	g_clear_object(&self->channel);
	g_clear_pointer(&self->input_action, g_free);
	g_clear_object(&self->im_context);
	if (self->text_model != nullptr) {
	delete self->text_model;
	self->text_model = nullptr;
	}

	G_OBJECT_CLASS(fl_text_input_plugin_parent_class)->dispose(object);
	}

	static void fl_text_input_plugin_class_init(FlTextInputPluginClass* klass) {
	G_OBJECT_CLASS(klass)->dispose = fl_text_input_plugin_dispose;
	}

	static void fl_text_input_plugin_init(FlTextInputPlugin* self) {
	self->client_id = kClientIdUnset;
	self->im_context = gtk_im_multicontext_new();
	g_signal_connect_object(self->im_context, "commit", G_CALLBACK(im_commit_cb),
	self, G_CONNECT_SWAPPED);
	g_signal_connect_object(self->im_context, "retrieve-surrounding",
	G_CALLBACK(im_retrieve_surrounding_cb), self,
	G_CONNECT_SWAPPED);
	g_signal_connect_object(self->im_context, "delete-surrounding",
	G_CALLBACK(im_delete_surrounding_cb), self,
	G_CONNECT_SWAPPED);
	self->text_model = new flutter::TextInputModel("", "");
	}

	FlTextInputPlugin* fl_text_input_plugin_new(FlBinaryMessenger* messenger) {
	g_return_val_if_fail(FL_IS_BINARY_MESSENGER(messenger), nullptr);

	FlTextInputPlugin* self = FL_TEXT_INPUT_PLUGIN(
	g_object_new(fl_text_input_plugin_get_type(), nullptr));

	g_autoptr(FlJsonMethodCodec) codec = fl_json_method_codec_new();
	self->channel =
	fl_method_channel_new(messenger, kChannelName, FL_METHOD_CODEC(codec));
	fl_method_channel_set_method_call_handler(self->channel, method_call_cb, self,
	nullptr);

	return self;
	}

	gboolean fl_text_input_plugin_filter_keypress(FlTextInputPlugin* self,
	GdkEventKey* event) {
	g_return_val_if_fail(FL_IS_TEXT_INPUT_PLUGIN(self), FALSE);
	if (gtk_im_context_filter_keypress(self->im_context, event))
	return TRUE;

	// Handle navigation keys.
	gboolean changed = FALSE;
	if (event->type == GDK_KEY_PRESS) {
	switch (event->keyval) {
	case GDK_KEY_BackSpace:
	changed = self->text_model->Backspace();
	break;
	case GDK_KEY_Delete:
	case GDK_KEY_KP_Delete:
	// Already handled inside Flutter.
	break;
	case GDK_KEY_End:
	case GDK_KEY_KP_End:
	changed = self->text_model->MoveCursorToEnd();
	break;
	case GDK_KEY_Return:
	case GDK_KEY_KP_Enter:
	case GDK_KEY_ISO_Enter:
	perform_action(self);
	break;
	case GDK_KEY_Home:
	case GDK_KEY_KP_Home:
	changed = self->text_model->MoveCursorToBeginning();
	break;
	case GDK_KEY_Left:
	case GDK_KEY_KP_Left:
	// Already handled inside Flutter.
	break;
	case GDK_KEY_Right:
	case GDK_KEY_KP_Right:
	// Already handled inside Flutter.
	break;
	}
	}

	if (changed)
	update_editing_state(self);

	return FALSE;
	}