gtk_box_pack_start

在GTK中，gtk_box_pack_start()函数是用来将一个部件加入到GTK容器（如GtkBox、GtkGrid等）的起始位置的函数。它的函数原型如下：

void gtk_box_pack_start (GtkBox *box, GtkWidget *child, gboolean expand, gboolean fill, guint padding);

参数含义如下：

- `box`：要加入部件的GTK容器。
- `child`：要加入的部件。
- `expand`：表示是否允许部件在容器中扩展。
- `fill`：表示是否允许部件填充容器中的空间。
- `padding`：表示部件与容器边框之间的间距。

使用gtk_box_pack_start()函数将部件加入到GTK容器的起始位置，可以让部件在容器中处于左侧或者顶部的位置。如果需要将部件加入到容器的中间或者末尾位置，可以使用gtk_box_pack_end()和gtk_box_pack_start()函数。

相关问题

qemu 开发gtk界面 demo

以下是一个简单的 QEMU GTK GUI 应用程序的示例代码：

#include <gtk/gtk.h>
#include <glib.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#include "qemu/qemu.h"
#include "qemu/qemu-option.h"

GtkWidget *window;
GtkWidget *start_button;
GtkWidget *stop_button;
GtkWidget *console_text;

QEMUOption option;

static void on_start_button_clicked(GtkWidget *widget, gpointer data)
{
    char *cmd = g_strdup_printf("qemu-system-%s -hda %s", option.arch, option.disk_image);
    FILE *fp = popen(cmd, "r");
    if (fp == NULL) {
        perror("popen failed");
        return;
    }
    char buf[1024];
    while (fgets(buf, sizeof(buf), fp) != NULL) {
        gtk_text_buffer_insert_at_cursor(gtk_text_view_get_buffer(GTK_TEXT_VIEW(console_text)), buf, strlen(buf));
    }
    pclose(fp);
}

static void on_stop_button_clicked(GtkWidget *widget, gpointer data)
{
    // TODO: Stop the QEMU process
}

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

int main(int argc, char *argv[])
{
    gtk_init(&argc, &argv);

    // Initialize the QEMU option
    option.arch = "x86_64";
    option.disk_image = "/path/to/disk_image.img";

    // Create the main window
    window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
    gtk_window_set_title(GTK_WINDOW(window), "QEMU GUI");
    gtk_window_set_default_size(GTK_WINDOW(window), 640, 480);
    g_signal_connect(window, "destroy", G_CALLBACK(on_window_destroy), NULL);

    // Create the start button
    start_button = gtk_button_new_with_label("Start QEMU");
    g_signal_connect(start_button, "clicked", G_CALLBACK(on_start_button_clicked), NULL);

    // Create the stop button
    stop_button = gtk_button_new_with_label("Stop QEMU");
    g_signal_connect(stop_button, "clicked", G_CALLBACK(on_stop_button_clicked), NULL);

    // Create the console text view
    console_text = gtk_text_view_new();
    gtk_text_view_set_editable(GTK_TEXT_VIEW(console_text), FALSE);
    gtk_text_view_set_wrap_mode(GTK_TEXT_VIEW(console_text), GTK_WRAP_WORD_CHAR);

    // Create a vertical box layout
    GtkWidget *vbox = gtk_box_new(GTK_ORIENTATION_VERTICAL, 5);
    gtk_container_add(GTK_CONTAINER(window), vbox);

    // Add the start button to the layout
    gtk_box_pack_start(GTK_BOX(vbox), start_button, FALSE, FALSE, 0);

    // Add the stop button to the layout
    gtk_box_pack_start(GTK_BOX(vbox), stop_button, FALSE, FALSE, 0);

    // Add the console text view to the layout
    GtkWidget *scroll = gtk_scrolled_window_new(NULL, NULL);
    gtk_container_add(GTK_CONTAINER(scroll), console_text);
    gtk_box_pack_start(GTK_BOX(vbox), scroll, TRUE, TRUE, 0);

    // Show all widgets
    gtk_widget_show_all(window);

    // Enter the GTK main loop
    gtk_main();

    return 0;
}

该示例代码仅包含了启动和停止 QEMU 的基本逻辑，并没有对 QEMU 进行更高级的配置和控制。你可以根据需要修改代码，并添加其他功能来完善你的 QEMU GTK GUI 应用程序。

gtk制作一个音乐盒代码

下面是一个简单的GTK音乐盒的代码示例，包括基本的UI设计和音乐播放逻辑：

#include <gtk/gtk.h>
#include <glib.h>
#include <glib/gprintf.h>
#include <glib-object.h>
#include <gst/gst.h>
#include <gst/interfaces/xoverlay.h>

static GtkWidget *window;
static GtkWidget *play_button;
static GtkWidget *stop_button;
static GtkWidget *pause_button;
static GtkWidget *next_button;
static GtkWidget *prev_button;
static GtkWidget *volume_scale;
static GtkWidget *song_list;

static GstElement *playbin;
static GstElement *video_sink;

static GList *songs = NULL;
static GList *current_song = NULL;

/* Forward declarations */
static void load_songs();
static void play_song(GList *song);
static void update_song_list();

/* Callback for the "play" button */
static void on_play_button_clicked(GtkButton *button, gpointer user_data)
{
    if (current_song == NULL) {
        current_song = g_list_first(songs);
    }
    play_song(current_song);
}

/* Callback for the "stop" button */
static void on_stop_button_clicked(GtkButton *button, gpointer user_data)
{
    gst_element_set_state(playbin, GST_STATE_NULL);
}

/* Callback for the "pause" button */
static void on_pause_button_clicked(GtkButton *button, gpointer user_data)
{
    GstState state;
    gst_element_get_state(playbin, &state, NULL, GST_CLOCK_TIME_NONE);
    if (state == GST_STATE_PLAYING) {
        gst_element_set_state(playbin, GST_STATE_PAUSED);
    } else if (state == GST_STATE_PAUSED) {
        gst_element_set_state(playbin, GST_STATE_PLAYING);
    }
}

/* Callback for the "next" button */
static void on_next_button_clicked(GtkButton *button, gpointer user_data)
{
    if (current_song == NULL) {
        current_song = g_list_first(songs);
    } else {
        current_song = g_list_next(current_song);
        if (current_song == NULL) {
            current_song = g_list_first(songs);
        }
    }
    play_song(current_song);
}

/* Callback for the "prev" button */
static void on_prev_button_clicked(GtkButton *button, gpointer user_data)
{
    if (current_song == NULL) {
        current_song = g_list_last(songs);
    } else {
        current_song = g_list_previous(current_song);
        if (current_song == NULL) {
            current_song = g_list_last(songs);
        }
    }
    play_song(current_song);
}

/* Callback for the volume scale */
static void on_volume_scale_changed(GtkRange *range, gpointer user_data)
{
    gdouble value = gtk_range_get_value(range);
    g_object_set(G_OBJECT(playbin), "volume", value, NULL);
}

/* Load songs from a directory */
static void load_songs()
{
    GDir *dir = g_dir_open("music", 0, NULL);
    const gchar *filename;
    while ((filename = g_dir_read_name(dir)) != NULL) {
        gchar *path = g_build_filename("music", filename, NULL);
        songs = g_list_append(songs, path);
    }
    g_dir_close(dir);
}

/* Play a song */
static void play_song(GList *song)
{
    gchar *path = song->data;
    gst_element_set_state(playbin, GST_STATE_NULL);

    g_object_set(G_OBJECT(playbin), "uri", g_filename_to_uri(path, NULL), NULL);
    gst_element_set_state(playbin, GST_STATE_PLAYING);

    current_song = song;
    update_song_list();
}

/* Update the song list */
static void update_song_list()
{
    gtk_list_store_clear(GTK_LIST_STORE(gtk_tree_view_get_model(GTK_TREE_VIEW(song_list))));
    GList *node = songs;
    while (node != NULL) {
        gchar *path = node->data;
        gchar *name = g_path_get_basename(path);
        GtkTreeIter iter;
        gtk_list_store_append(GTK_LIST_STORE(gtk_tree_view_get_model(GTK_TREE_VIEW(song_list))), &iter);
        gtk_list_store_set(GTK_LIST_STORE(gtk_tree_view_get_model(GTK_TREE_VIEW(song_list))), &iter, 0, name, -1);
        if (node == current_song) {
            gtk_list_store_set(GTK_LIST_STORE(gtk_tree_view_get_model(GTK_TREE_VIEW(song_list))), &iter, 1, TRUE, -1);
        }
        g_free(name);
        node = g_list_next(node);
    }
}

int main(int argc, char *argv[])
{
    /* Initialize GTK+ */
    gtk_init(&argc, &argv);

    /* Initialize GStreamer */
    gst_init(&argc, &argv);

    /* Create the main window */
    window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
    gtk_window_set_title(GTK_WINDOW(window), "GTK Music Box");
    gtk_window_set_default_size(GTK_WINDOW(window), 500, 300);
    g_signal_connect(window, "destroy", G_CALLBACK(gtk_main_quit), NULL);

    /* Create the main layout */
    GtkBox *layout = GTK_BOX(gtk_box_new(GTK_ORIENTATION_VERTICAL, 0));
    gtk_container_add(GTK_CONTAINER(window), GTK_WIDGET(layout));

    /* Create the song list */
    GtkScrolledWindow *song_list_scroll = GTK_SCROLLED_WINDOW(gtk_scrolled_window_new(NULL, NULL));
    gtk_scrolled_window_set_policy(song_list_scroll, GTK_POLICY_AUTOMATIC, GTK_POLICY_AUTOMATIC);
    gtk_box_pack_start(layout, GTK_WIDGET(song_list_scroll), TRUE, TRUE, 0);

    song_list = gtk_tree_view_new_with_model(GTK_TREE_MODEL(gtk_list_store_new(2, G_TYPE_STRING, G_TYPE_BOOLEAN)));
    GtkTreeViewColumn *column = gtk_tree_view_column_new();
    gtk_tree_view_column_set_title(column, "Song");
    gtk_tree_view_append_column(GTK_TREE_VIEW(song_list), column);
    GtkCellRenderer *renderer = gtk_cell_renderer_text_new();
    gtk_tree_view_column_pack_start(column, renderer, TRUE);
    gtk_tree_view_column_add_attribute(column, renderer, "text", 0);
    renderer = gtk_cell_renderer_toggle_new();
    gtk_tree_view_column_pack_start(column, renderer, FALSE);
    gtk_tree_view_column_add_attribute(column, renderer, "active", 1);
    gtk_container_add(GTK_CONTAINER(song_list_scroll), GTK_WIDGET(song_list));

    /* Load the songs */
    load_songs();

    /* Create the play button */
    play_button = gtk_button_new_with_label("Play");
    gtk_box_pack_start(layout, play_button, FALSE, FALSE, 0);
    g_signal_connect(play_button, "clicked", G_CALLBACK(on_play_button_clicked), NULL);

    /* Create the stop button */
    stop_button = gtk_button_new_with_label("Stop");
    gtk_box_pack_start(layout, stop_button, FALSE, FALSE, 0);
    g_signal_connect(stop_button, "clicked", G_CALLBACK(on_stop_button_clicked), NULL);

    /* Create the pause button */
    pause_button = gtk_button_new_with_label("Pause");
    gtk_box_pack_start(layout, pause_button, FALSE, FALSE, 0);
    g_signal_connect(pause_button, "clicked", G_CALLBACK(on_pause_button_clicked), NULL);

    /* Create the next button */
    next_button = gtk_button_new_with_label("Next");
    gtk_box_pack_start(layout, next_button, FALSE, FALSE, 0);
    g_signal_connect(next_button, "clicked", G_CALLBACK(on_next_button_clicked), NULL);

    /* Create the prev button */
    prev_button = gtk_button_new_with_label("Prev");
    gtk_box_pack_start(layout, prev_button, FALSE, FALSE, 0);
    g_signal_connect(prev_button, "clicked", G_CALLBACK(on_prev_button_clicked), NULL);

    /* Create the volume scale */
    volume_scale = gtk_scale_new_with_range(GTK_ORIENTATION_HORIZONTAL, 0.0, 1.0, 0.1);
    gtk_box_pack_start(layout, volume_scale, FALSE, FALSE, 0);
    g_signal_connect(volume_scale, "value-changed", G_CALLBACK(on_volume_scale_changed), NULL);

    /* Create the audio player */
    playbin = gst_element_factory_make("playbin", NULL);
    g_object_set(G_OBJECT(playbin), "video-sink", NULL, NULL);
    g_object_set(G_OBJECT(playbin), "volume", gtk_range_get_value(GTK_RANGE(volume_scale)), NULL);

    /* Start the main loop */
    update_song_list();
    gtk_widget_show_all(window);
    gtk_main();

    return 0;
}

这是一个简单的GTK音乐盒的代码，你可以根据你的需求进行修改。