Question

我试图抓住点击的协调。我创建了Gtk.Window，EventBox并将Image放入，将一些EventButton连接到button_press_event并将一些方法连接到此信号。此方法尝试从EventButton对象获取x和y，但它们始终为0.有源代码：

using Gtk;
public class ComixTranslator : Window 
{
private Gtk.Image CurPage;
private Gdk.Pixbuf Canvas;
private Gtk.EventBox eventbox1;
private Gdk.EventButton ebutton1;

public bool FillDot() {
    GLib.message("pressed in %g,%g",ebutton1.x,ebutton1.y);
    return true;
}

public ComixTranslator () {
    this.title = "Image Click Sample";
    this.window_position = Gtk.WindowPosition.CENTER;
    this.destroy.connect(Gtk.main_quit);
    this.set_default_size(800,600);

    this.CurPage = new Gtk.Image();
    this.CurPage.set_from_file("test.jpg");
    this.Canvas = CurPage.pixbuf;

    this.eventbox1 = new Gtk.EventBox();
    this.eventbox1.button_press_event(ebutton1);
    this.eventbox1.button_press_event.connect(FillDot);
    this.eventbox1.add(CurPage);

    this.add(eventbox1);
}

public static int main(string[] args) {
    Gtk.init(ref args);

    ComixTranslator MainWindow = new ComixTranslator();
    MainWindow.show_all();
    Gtk.main();
    return 0;
}
}

Answer 1

您似乎对信号如何工作感到困惑 - 您可能想要考虑阅读that part of the Vala Tutorial。这是一个更正版本：

using Gtk;
public class ComixTranslator : Window 
{
  private Gtk.Image CurPage;
  private Gdk.Pixbuf Canvas;
  private Gtk.EventBox eventbox1;

  public bool FillDot(Gtk.Widget sender, Gdk.EventButton evt) {
    GLib.message("pressed in %g,%g",evt.x,evt.y);
    return true;
  }

  public ComixTranslator () {
    this.title = "Image Click Sample";
    this.window_position = Gtk.WindowPosition.CENTER;
    this.destroy.connect(Gtk.main_quit);
    this.set_default_size(800,600);

    this.CurPage = new Gtk.Image();
    this.CurPage.set_from_file("test.jpg");
    this.Canvas = CurPage.pixbuf;

    this.eventbox1 = new Gtk.EventBox();
    this.eventbox1.button_press_event.connect(FillDot);
    this.eventbox1.add(CurPage);

    this.add(eventbox1);
  }

  public static int main(string[] args) {
    Gtk.init(ref args);

    ComixTranslator MainWindow = new ComixTranslator();
    MainWindow.show_all();
    Gtk.main();
    return 0;
  }
}

请注意，回调接受Gdk.EventButton作为参数。在您的代码中，您有this.eventbox1.button_press_event(ebutton1);，它将发出 button_press_event信号，并将来自ebutton1的数据作为其参数。

Vala Image点击事件。如何获得点击的坐标？

1 个答案: