Android Development Learning Path-use of basic events

1. How the event responds.

Setonclicklistener (view. Onclicklistener l);

Setonfocuschangelistener (View.onfocuschangelistener L)

Setonlongclicklistener (view. Ononclicklistener l);

Setontouchlistener (view. Ontouchlisterner l);

Three ways to respond to events.

The first way:

Final Button Button1 = (Button) Findviewbyid (R.id.button1);

Button1.setonclicklistener (New Onclicklistener () {

public void OnClick (View V) {

Text.set ...;

}

});

The second way:

When defining a class, extend Activity implements Onclicklistener,

Add event Button1.setonclicklistener to the button (this);

Implements the event onclick, public void onclick (View v)

{

Switch (V.getid ()) {

Case

Break

Default

Break

}

}

The third Way: not commonly used.

2. Keyboard response events, i.e. keys

Boolean onKeyDown (int keycode, keyevent msg);

3. Touch Events

Ontouchevent (Motionevent event)

Getaction (); GetX (); GetY () respectively is to get the corresponding action, already coordinates the position.

How to draw:

1. Define a Paint class container, paint class can set the color of paint, Paint.setcolor (color.red); The paint here is the equivalent of a pen, with what color of the pen, what shape of the pen, to paint.

2. Overloaded OnDraw function protect void OnDraw (canvas canvas)//canvas is a canvas

Canvas.drawcircle (X,y,radiu,paint)//indicates, respectively, the horizontal ordinate, radius, and paint brush of the drawing point.

4. Jump and event transfer between screens

Android Development Learning Path-use of basic events