¡Hola a todos! En mi primer post, quiero hablar sobre la creación de una radio simple en el idioma Vala. Nunca he sido programador, sino más bien un aficionado y escribí todos mis desarrollos en Java, pero como uso GNU / Linux en mi computadora, es decir, el viejo Debian, e incluso en GNOME, pensé, ¿por qué no intentar escribir algo, cualquier cosa para este sistema.
Capacitación
¡Dicho y hecho! Decidí escribir en el editor de texto nativo GEdit. Compilador y paquete instalados para el desarrollo GTK:
sudo apt install valac libgtk-3-dev
También necesitamos el paquete de desarrollador GStreamer. Vamos a instalarlo también:
sudo apt install libgstreamer1.0-dev
¡Siga adelante! En el editor, debe habilitar la compatibilidad con el terminal integrado y mostrar el panel inferior, donde aparecerá el terminal. Además, para mayor comodidad, debe incluir completar palabras, paréntesis y otras funciones. Todos están en la lista de módulos. Puede encontrarlo en la configuración del editor. Cosas muy útiles. En esencia, convierten un editor de texto normal en un entorno de desarrollo básico.
Interfaz grafica
Archivos
Entonces, tenemos el editor listo. ¿Dónde empezar? ¡Desde la interfaz, por supuesto! Escribiremos la GUI con bolígrafos en el editor. Pero primero sobre el código en sí. Tendremos dos archivos. Uno se llama Application.vala y tiene este contenido:
namespace Raddiola {
public class Application : Gtk.Application {
public MainWindow app_window;
public Application() {
Object(flags: ApplicationFlags.FLAGS_NONE, application_id: "com.github.alexkdeveloper.raddiola");
}
protected override void activate() {
if(get_windows().length() > 0) {
app_window.present();
return;
}
app_window = new MainWindow(this);
app_window.show_all();
}
public static int main(string[] args) {
Gst.init (ref args);
var app = new Raddiola.Application();
return app.run(args);
}
}
}
. MainWindow.vala .
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, :
using Gtk;
using Gst;
namespace Raddiola {
public class MainWindow : Gtk.ApplicationWindow {
private Stack stack;
private Box vbox_player_page;
private Box vbox_edit_page;
private dynamic Element player;
private Gtk.ListStore list_store;
private TreeView tree_view;
private GLib.List<string> list;
private Entry entry_name;
private Entry entry_url;
private Button back_button;
private Button add_button;
private Button delete_button;
private Button edit_button;
private Button play_button;
private Button stop_button;
private string directory_path;
private string item;
private int mode;
public MainWindow(Gtk.Application application) {
GLib.Object(application: application,
title: "Raddiola",
window_position: WindowPosition.CENTER,
resizable: true,
height_request: 500,
width_request: 500,
border_width: 10);
}
construct {
Gtk.HeaderBar headerbar = new Gtk.HeaderBar();
headerbar.get_style_context().add_class(Gtk.STYLE_CLASS_FLAT);
headerbar.show_close_button = true;
set_titlebar(headerbar);
back_button = new Gtk.Button ();
back_button.set_image (new Gtk.Image.from_icon_name ("go-previous-symbolic", Gtk.IconSize.SMALL_TOOLBAR));
back_button.vexpand = false;
add_button = new Gtk.Button ();
add_button.set_image (new Gtk.Image.from_icon_name ("list-add-symbolic", Gtk.IconSize.SMALL_TOOLBAR));
add_button.vexpand = false;
delete_button = new Gtk.Button ();
delete_button.set_image (new Gtk.Image.from_icon_name ("list-remove-symbolic", Gtk.IconSize.SMALL_TOOLBAR));
delete_button.vexpand = false;
edit_button = new Gtk.Button ();
edit_button.set_image (new Gtk.Image.from_icon_name ("document-edit-symbolic", Gtk.IconSize.SMALL_TOOLBAR));
edit_button.vexpand = false;
play_button = new Gtk.Button();
play_button.set_image (new Gtk.Image.from_icon_name ("media-playback-start-symbolic", Gtk.IconSize.SMALL_TOOLBAR));
play_button.vexpand = false;
stop_button = new Gtk.Button();
stop_button.set_image (new Gtk.Image.from_icon_name ("media-playback-stop-symbolic", Gtk.IconSize.SMALL_TOOLBAR));
stop_button.vexpand = false;
. , .
back_button.set_tooltip_text("back");
add_button.set_tooltip_text("add station");
delete_button.set_tooltip_text("delete station");
edit_button.set_tooltip_text("edit station");
play_button.set_tooltip_text("play");
stop_button.set_tooltip_text("stop");
back_button.clicked.connect(on_back_clicked);
add_button.clicked.connect(on_add_clicked);
delete_button.clicked.connect(on_delete_dialog);
edit_button.clicked.connect(on_edit_clicked);
play_button.clicked.connect(on_play_station);
stop_button.clicked.connect(on_stop_station);
headerbar.pack_start(back_button);
headerbar.pack_start(add_button);
headerbar.pack_start(delete_button);
headerbar.pack_start(edit_button);
headerbar.pack_end(stop_button);
headerbar.pack_end(play_button);
, set_widget_visible
:
set_widget_visible(back_button,false);
set_widget_visible(stop_button,false);
:
private void set_widget_visible (Gtk.Widget widget, bool visible) {
widget.no_show_all = !visible;
widget.visible = visible;
}
, . . :
stack = new Stack();
stack.set_transition_duration (600);
stack.set_transition_type (StackTransitionType.SLIDE_LEFT_RIGHT);
add (stack);//
list_store = new Gtk.ListStore(Columns.N_COLUMNS, typeof(string));//
tree_view = new TreeView.with_model(list_store);
var text = new CellRendererText ();
var column = new TreeViewColumn ();
column.pack_start (text, true);
column.add_attribute (text, "markup", Columns.TEXT);
tree_view.append_column (column);
tree_view.set_headers_visible (false);
tree_view.cursor_changed.connect(on_select_item);
var scroll = new ScrolledWindow (null, null);
scroll.set_policy (PolicyType.AUTOMATIC, PolicyType.AUTOMATIC);
scroll.add (this.tree_view);
vbox_player_page = new Box(Orientation.VERTICAL,20);
vbox_player_page.pack_start(scroll,true,true,0);
stack.add(vbox_player_page);//
. . , URL. , .
entry_name = new Entry();
entry_name.set_icon_from_icon_name (Gtk.EntryIconPosition.SECONDARY, "edit-clear-symbolic");
entry_name.icon_press.connect ((pos, event) => {
if (pos == Gtk.EntryIconPosition.SECONDARY) {
entry_name.set_text("");//
}
});
var label_name = new Label.with_mnemonic ("_Name:");
var hbox_name = new Box (Orientation.HORIZONTAL, 20);
hbox_name.pack_start (label_name, false, true, 0);
hbox_name.pack_start (entry_name, true, true, 0);
entry_url = new Entry();
entry_url.set_icon_from_icon_name (Gtk.EntryIconPosition.SECONDARY, "edit-clear-symbolic");
entry_url.icon_press.connect ((pos, event) => {
if (pos == Gtk.EntryIconPosition.SECONDARY) {
entry_url.set_text("");// URL
}
});
var label_url = new Label.with_mnemonic ("_URL:");
var hbox_url = new Box (Orientation.HORIZONTAL, 20);
hbox_url.pack_start (label_url, false, true, 0);
hbox_url.pack_start (entry_url, true, true, 0);
var button_ok = new Button.with_label("OK");
button_ok.clicked.connect(on_ok_clicked);
vbox_edit_page = new Box(Orientation.VERTICAL,20);
vbox_edit_page.pack_start(hbox_name,false,true,0);
vbox_edit_page.pack_start(hbox_url,false,true,0);
vbox_edit_page.pack_start(button_ok,false,true,0);
stack.add(vbox_edit_page);
stack.visible_child = vbox_player_page;//
GUI . player,
c . . .
player = ElementFactory.make ("playbin", "play");//
directory_path = Environment.get_home_dir()+"/.stations_for_radio_app";
GLib.File file = GLib.File.new_for_path(directory_path);
if(!file.query_exists()){
try{
file.make_directory();//
}catch(Error e){
stderr.printf ("Error: %s\n", e.message);
}
create_default_stations();//
}
show_stations();//
}
create_default_stations.
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private void create_default_stations(){
string[] name_station = {"NonStopPlay","Classical Music","Fip Radio","Jazz Legends","Joy Radio","Live-icy","Music Radio","Radio Electron","Dubstep","Trancemission"};
string[] url_station = {"http://stream.nonstopplay.co.uk/nsp-128k-mp3","http://stream.srg-ssr.ch/m/rsc_de/mp3_128","http://direct.fipradio.fr/live/fip-midfi.mp3","http://jazz128legends.streamr.ru/","http://airtime.joyradio.cc:8000/airtime_192.mp3","http://live-icy.gss.dr.dk:8000/A/A05H.mp3","http://ice-the.musicradio.com/CapitalXTRANationalMP3","http://radio-electron.ru:8000/128","http://air.radiorecord.ru:8102/dub_320","http://air.radiorecord.ru:8102/tm_320"};
for(int i=0;i<10;i++){
try {
FileUtils.set_contents (directory_path+"/"+name_station[i], url_station[i]);
} catch (Error e) {
stderr.printf ("Error: %s\n", e.message);
}
}
}
show_stations:
private void show_stations () {
list_store.clear();
list = new GLib.List<string> ();
try {
Dir dir = Dir.open (directory_path, 0);
string? name = null;
while ((name = dir.read_name ()) != null) {
list.append(name);
}
} catch (FileError err) {
stderr.printf (err.message);
}
TreeIter iter;
foreach (string item in list) {
list_store.append(out iter);
list_store.set(iter, Columns.TEXT, item);//
}
}
/
alert.
:
private void alert (string str){
var dialog_alert = new Gtk.MessageDialog(this, Gtk.DialogFlags.MODAL, Gtk.MessageType.INFO, Gtk.ButtonsType.OK, str);
dialog_alert.set_title("Message");
dialog_alert.run();
dialog_alert.destroy();
}
:
private void on_play_station(){ //
var selection = tree_view.get_selection();
selection.set_mode(SelectionMode.SINGLE);
TreeModel model;
TreeIter iter;
if (!selection.get_selected(out model, out iter)) {
alert("Choose a station");
return;
}
string uri;
try {
FileUtils.get_contents (directory_path+"/"+item, out uri);
} catch (Error e) {
stderr.printf ("Error: %s\n", e.message);
}
player.uri = uri;
player.set_state (State.PLAYING);
set_widget_visible(play_button,false);
set_widget_visible(stop_button,true);
}
private void on_stop_station(){//
player.set_state (State.READY);
set_widget_visible(play_button,true);
set_widget_visible(stop_button,false);
}
:
private void on_add_clicked () {//
stack.visible_child = vbox_edit_page;
set_buttons_on_edit_page();
mode = 1;
if(!is_empty(entry_name.get_text())){
entry_name.set_text("");
}
if(!is_empty(entry_url.get_text())){
entry_url.set_text("");
}
}
private void on_edit_clicked(){//
var selection = tree_view.get_selection();
selection.set_mode(SelectionMode.SINGLE);
TreeModel model;
TreeIter iter;
if (!selection.get_selected(out model, out iter)) {
alert("Choose a station");
return;
}
stack.visible_child = vbox_edit_page;
set_buttons_on_edit_page();
mode = 0;
entry_name.set_text(item);//
string url;
try {
FileUtils.get_contents (directory_path+"/"+item, out url);
} catch (Error e) {
stderr.printf ("Error: %s\n", e.message);
}
entry_url.set_text(url);// URL
}
. mode
. : . .
private void on_ok_clicked(){
if(is_empty(entry_name.get_text())){
alert("Enter the name");
entry_name.grab_focus();
return;
}
if(is_empty(entry_url.get_text())){
alert("Enter the url");
entry_url.grab_focus();
return;
}
switch(mode){//
case 0://
GLib.File select_file = GLib.File.new_for_path(directory_path+"/"+item);
GLib.File edit_file = GLib.File.new_for_path(directory_path+"/"+entry_name.get_text().strip());
if (select_file.get_basename() != edit_file.get_basename() && !edit_file.query_exists()){
FileUtils.rename(select_file.get_path(), edit_file.get_path());
if(!edit_file.query_exists()){
alert("Rename failed");
return;
}
try {
FileUtils.set_contents (edit_file.get_path(), entry_url.get_text().strip());
} catch (Error e) {
stderr.printf ("Error: %s\n", e.message);
}
}else{
if (select_file.get_basename() != edit_file.get_basename()) {
alert("A station with the same name already exists");
entry_name.grab_focus();
return;
}
try {
FileUtils.set_contents (edit_file.get_path(), entry_url.get_text().strip());
} catch (Error e) {
stderr.printf ("Error: %s\n", e.message);
}
}
show_stations();
break;
case 1://
GLib.File file = GLib.File.new_for_path(directory_path+"/"+entry_name.get_text().strip());
if(file.query_exists()){
alert("A station with the same name already exists");
entry_name.grab_focus();
return;
}
try {
FileUtils.set_contents (file.get_path(), entry_url.get_text().strip());
} catch (Error e) {
stderr.printf ("Error: %s\n", e.message);
}
if(!file.query_exists()){
alert("Add failed");
return;
}else{
show_stations();
}
break;
}
on_back_clicked();
}
:
private void on_delete_dialog(){
var selection = tree_view.get_selection();
selection.set_mode(SelectionMode.SINGLE);
TreeModel model;
TreeIter iter;
if (!selection.get_selected(out model, out iter)) {
alert("Choose a station");
return;
}
GLib.File file = GLib.File.new_for_path(directory_path+"/"+item);
var dialog_delete_station = new Gtk.MessageDialog(this, Gtk.DialogFlags.MODAL,Gtk.MessageType.QUESTION, Gtk.ButtonsType.OK_CANCEL, "Delete station "+file.get_basename()+" ?");
dialog_delete_station.set_title("Question");
Gtk.ResponseType result = (ResponseType)dialog_delete_station.run ();
dialog_delete_station.destroy();
if(result==Gtk.ResponseType.OK){
FileUtils.remove (directory_path+"/"+item);
if(file.query_exists()){
alert("Delete failed");
}else{
show_stations();//
}
}
}
:
private void set_buttons_on_player_page(){//
set_widget_visible(back_button,false);
set_widget_visible(add_button,true);
set_widget_visible(delete_button,true);
set_widget_visible(edit_button,true);
}
private void set_buttons_on_edit_page(){// /
set_widget_visible(back_button,true);
set_widget_visible(add_button,false);
set_widget_visible(delete_button,false);
set_widget_visible(edit_button,false);
}
item
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private void on_select_item () {
var selection = tree_view.get_selection();
selection.set_mode(SelectionMode.SINGLE);
TreeModel model;
TreeIter iter;
if (!selection.get_selected(out model, out iter)) {
return;
}
TreePath path = model.get_path(iter);
var index = int.parse(path.to_string());
if (index >= 0) {
item = list.nth_data(index);//
}
}
:
private void on_back_clicked(){
stack.visible_child = vbox_player_page;
set_buttons_on_player_page();
}
is_empty:
private bool is_empty(string str){
return str.strip().length == 0;
}
:
private enum Columns {
TEXT, N_COLUMNS
}
:
valac --pkg gtk+-3.0 --pkg gstreamer-1.0 Application.vala MainWindow.vala
:
./Application
→ GitHub
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