add main.cpp

Signed-off-by: Zengtudor <zengtudor@outlook.com>

src/main.cpp

@@ -0,0 +1,27 @@
+#include<FL/Fl.H>
+#include<FL/Fl_Window.H>
+#include<FL/Fl_Box.H>
+#include<FL/Fl_Button.H>
+#include<FL/fl_ask.H>
+
+#include<bits/stdc++.h>
+using namespace std;
+
+int main(int argc,char *argv[]){
+    auto window = make_unique<Fl_Window>(500,300);
+    auto box = make_unique<Fl_Box>(20,40,260,100,"Hello world");
+    box->box(FL_UP_BOX);
+    box->labelsize(20);
+    box->labelfont(FL_BOLD+FL_ITALIC);
+    box->labeltype(FL_SHADOW_LABEL);
+
+    auto btn = make_unique<Fl_Button>(20,200,100,50,"btn");
+    btn->callback((Fl_Callback*)[](Fl_Widget *w,void *v)->void{
+        fl_alert("btn callback");
+    });
+
+    window->end();
+    window->show(argc,argv);
+    
+    return Fl::run();
+}