gtk在對話框中顯示對話框

Question

我正在編寫一個gtk程序， 在我的應用程序的某個位置，我調用gtkdialog來獲取用戶的輸入。 我想要做的是關閉當前對話框，並單擊確定按鈕時打開另一個對話框，我已經有一個功能做一些其他工作，在該功能中啓動對話框會很好。 這裏的父對話框代碼：

GtkWidget * new_button_dialog = gtk_dialog_new_with_buttons("new button",(GtkWindow *)container,GTK_DIALOG_DESTROY_WITH_PARENT,"OK", GTK_RESPONSE_OK,NULL); 
     GtkWidget * content_area = gtk_dialog_get_content_area (GTK_DIALOG (new_button_dialog)); 
     GtkWidget * button_name_label = gtk_label_new ("Press escape at any time to cancel.\ntype in the button name"); 
     gtk_container_add (GTK_CONTAINER (content_area) , button_name_label); 
     GtkWidget * button_name_entry = gtk_entry_new(); 
     gtk_entry_set_activates_default((GtkEntry*)button_name_entry,TRUE); 
     gtk_container_add(GTK_CONTAINER(content_area), button_name_entry); 
     GtkWidget * button_text_dialog = gtk_dialog_new_with_buttons("new button",(GtkWindow *)container,GTK_DIALOG_DESTROY_WITH_PARENT,"OK", GTK_RESPONSE_OK,NULL); 
     gtk_container_add (GTK_CONTAINER (container), button); 
     g_signal_connect(new_button_dialog,"response",G_CALLBACK (add_new_button),NULL); 
gtk_signal_connect_object (GTK_OBJECT (button), "clicked",GTK_SIGNAL_FUNC (gtk_widget_show_all),(GtkWidget*)new_button_dialog); 
     gtk_widget_show_all((GtkWidget *)container); 

Answer 1

對話的反應不能在創建的對話框相同功能的處理。這意味着在一個功能中，您不能創建對話框，處理其輸入，關閉對話框並打開新的對話框。從該函數退出時，不能完成該對話框條目爲空，並且只顯示第一個對話框。

它應該作爲一個單獨的事件處理程序鏈來完成。所有需要的變量（數據上下文）應該在這些單獨的處理程序之間使用指向保存該上下文的結構的指針進行傳輸。

下面的完整運行示例演示了這樣的流程。

在第一個對話框處理程序中，我們希望對主窗口和某個容器對象執行某些操作，也許我們需要在該主窗口的窗口小部件之間共享其他一些數據。針對此上下文聲明結構window_ctx_t。在關閉活動對話框之前，在該上下文中有一個布爾標誌來鎖定新對話鏈上的創建。

函數first_dialog_create使用文本輸入字段創建第一個對話框。它接收到window_ctx_t，其中存儲用於創建對話框的主窗口指針。現在我們需要附加到該對話框響應處理程序，並向處理程序提供其功能的足夠數據。在這個例子中，我們提供了用於讀取文本的文本輸入的指針。

使用提供的數據，響應處理程序add_new_button能夠讀取文本條目，創建一個附加到主窗口的新對話框，並使用提供的容器執行某些操作。

當不需要第一個對話框數據上下文時，通過在對話框銷燬處理程序中調用g_free()來釋放它。

構建例如：

gcc -Wall -g dialogs.c -o dialogs `pkg-config --cflags gtk+-2.0` `pkg-config --libs gtk+-2.0` 

實施例 「DIALOGS.C」

#include <gtk/gtk.h> 

typedef struct { 
    GtkWidget *container; 
    GtkWindow *window; 
    gboolean dialogs_created; 
} window_ctx_t; 

typedef struct { 
    GtkEntry *entry; 
    window_ctx_t *window_ctx; 
} first_dialog_data_t; 

static void first_dialog_create(gpointer context); 

static void another_dialog_response(GtkWidget *dialog, gint response_id, 
    gpointer ctx) 
{ 
    window_ctx_t *win_ctx = ctx; 

    gtk_widget_destroy(dialog); 
    win_ctx->dialogs_created = FALSE; 
} 

static void cleanup_first_dialog(GtkWidget *widget, gpointer data) 
{ 
    g_free(data); 
} 

/* response callback of the first dialog */ 
static void add_new_button(GtkWidget *dialog, gint response_id, 
    gpointer ctx) 
{ 
    GtkWidget *button; 
    GtkWidget *button_text_dialog; 
    first_dialog_data_t *data = ctx; 

    if (response_id != GTK_RESPONSE_OK) { 
     data->window_ctx->dialogs_created = FALSE; 
     goto Exit; 
    } 

    /* Create a new button with the label from text entry */ 
    button = gtk_button_new_with_label(gtk_entry_get_text(data->entry)); 
    /* When the button receives the "clicked" signal, it will again open 
    * "new button" dialog */ 
    g_signal_connect_swapped(button, "clicked", G_CALLBACK(first_dialog_create), 
     data->window_ctx); 
    /* add button to the container */ 
    gtk_container_add(GTK_CONTAINER(data->window_ctx->container), button); 
    /* show button */ 
    gtk_widget_show(button); 

    /* create another dialog */ 
    button_text_dialog = gtk_dialog_new_with_buttons("new button", 
     data->window_ctx->window, GTK_DIALOG_DESTROY_WITH_PARENT, "OK", 
     GTK_RESPONSE_OK, NULL); 
    g_signal_connect(button_text_dialog, "response", 
     G_CALLBACK(another_dialog_response), (gpointer)data->window_ctx); 

    gtk_widget_show_all(button_text_dialog); 

Exit: 
    gtk_widget_destroy(dialog); 
} 

static void first_dialog_create(gpointer context) 
{ 
    first_dialog_data_t *data; 
    window_ctx_t *win_ctx = context; 

    if (win_ctx->dialogs_created) 
     return; 

    /* lock buttons handler */ 
    win_ctx->dialogs_created = TRUE; 

    /* allocate structure for dialog context */ 
    data = g_new0(first_dialog_data_t, 1); 

    /* create first dialog, its label and text entry */ 
    GtkWidget *new_button_dialog = gtk_dialog_new_with_buttons("new button", 
     win_ctx->window, GTK_DIALOG_DESTROY_WITH_PARENT,"OK", 
     GTK_RESPONSE_OK, NULL); 

    GtkWidget *content_area = gtk_dialog_get_content_area(
    GTK_DIALOG(new_button_dialog)); 
    GtkWidget *button_name_label = gtk_label_new("Press escape at any time to " 
     "cancel.\ntype in the button name"); 
    gtk_container_add(GTK_CONTAINER(content_area), button_name_label); 

    GtkWidget * button_name_entry = gtk_entry_new(); 
    gtk_entry_set_activates_default((GtkEntry*)button_name_entry,TRUE); 
    gtk_container_add(GTK_CONTAINER(content_area), button_name_entry); 

    /* provide data to response handler */ 
    data->entry = (GtkEntry *)button_name_entry; 
    data->window_ctx = win_ctx; 
    g_signal_connect(new_button_dialog, "response", G_CALLBACK(add_new_button), 
     data); 

    /* handler to free dialog context 'data' when destroed */ 
    g_signal_connect(new_button_dialog, "destroy", 
     G_CALLBACK(cleanup_first_dialog), data); 

    /* show first dialog */ 
    gtk_widget_show_all(new_button_dialog); 
} 

static void destroy(GtkWidget *widget, gpointer data) 
{ 
    gtk_main_quit(); 
} 

int main(int argc, char *argv[]) 
{ 
    GtkWidget *window; 
    GtkWidget *box1; 
    GtkWidget *button; 
    window_ctx_t win_ctx; 

    gtk_init (&argc, &argv); 
    window = gtk_window_new(GTK_WINDOW_TOPLEVEL); 

    box1 = gtk_hbox_new(FALSE, 0); 
    gtk_container_add(GTK_CONTAINER(window), box1); 

    /* set window context */ 
    win_ctx.window = (GtkWindow *)window; 
    win_ctx.container = box1; 
    win_ctx.dialogs_created = FALSE; 

    g_signal_connect (window, "destroy", G_CALLBACK(destroy), NULL); 
    gtk_container_set_border_width(GTK_CONTAINER(window), 10); 

    button = gtk_button_new_with_label("Start"); 
    g_signal_connect_swapped(button, "clicked", G_CALLBACK(first_dialog_create), 
     &win_ctx); 
    gtk_container_add(GTK_CONTAINER(box1), button); 

    gtk_widget_show_all(window); 

    gtk_main(); 

    return 0; 
}