Java trial (3) AWT, UI

Program(Important points: control, layout, and event processing)

Code Import Java. AWT. * ;
Import Java. AWT. event. * ;

Public ClassMyframeExtendsFrame {

PrivateTextfield TF;

Public static void main (string ARGs []) {
myframe fr = New myframe ( " Hello out there! " );
Fr. initui ();
}

Public myframe (string Str) {
super (STR); /// call the constructor of the parent class
}

Public VoidInitui ()
{
//Frame
//Setsize (200,200 );
Setbackground (color. Red );

// Setlayout (null );
// Setlayout (New flowlayout ());
// Setlayout (New borderlayout ()); // Bad
Setlayout ( New Gridlayout ( 2 , 3 ));
// Setlayout (New cardlayout ()); // Crash
// Setlayout (New gridbaglayout ());

//Menus
Menubar MB= NewMenubar ();

Menu M1 =   New Menu ( " File " );
Menu m2 =   New Menu ( " Edit " );
Menu m3 =   New Menu ( " Help " );
MB. Add (M1 );
MB. Add (m2 );
MB. sethelpmenu (m3 );

Setmenubar (MB );

// controls
panel Pan = New Panel ();
pan. setsize ( 100 , 100 );
pan. setbackground (color. yellow);

Button B1= NewButton ("Button1");
B1.addactionlistener (NewButtonhandler ());

Button B2 =   New Button ( " Button2 " );
B2.addactionlistener ( New Actionlistener (){
Public   Void Actionreceivmed (actionevent E)
{
System. Out. println ( " Action 2 occurred " );
TF. settext ( " Action 2 occurred " );
}
});

TF = New Textfield ( 30 );

//Frames
Add (PAN );
Add (B1 );
Add (B2 );
Add (TF );

Pack ();

Addmousemotionlistener ( New Mousemotionadapter (){ // Anonymous class starts
Public   Void Mousedragged (mouseevent e ){
String s = " Mouse dragging: x = " + E. getx () + " Y = " + E. Gety ();
TF. settext (s );}
}); // Anonymous class ended

Setvisible ( True );
}
}

Class Buttonhandler Implements Actionlistener {
// Only the actionevent handler can implement the actionlistener interface.
Public   Void Actionreceivmed (actionevent E)
// The actionevent event object generated by the system is passed to this method as a parameter.
{
System. Out. println ( " Action occurred " );
// This interface has only one method. Therefore, when an event occurs, the system automatically calls this method.CodeWrite it in a method.
}
}

Compile and run

Javac myframe. Java

Java myframe