任务二

界面的设置 <ImageView        android:id="@+id/picture"        android:layout_width="80dp"        android:layout_height="80dp"        android:layout_gravity="center"/>        <Button            android:id="@+id/btn"            android:layout_gravity="center"            android:layout_width="wrap_content"            android:layout_height="wrap_content"            android:text="out"/>

对其功能的实现：protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_main);    picture = (ImageView) findViewById(R.id.picture);    btn = (Button) findViewById(R.id.btn);    this.btn.setOnClickListener(new View.OnClickListener() {        @Override        public void onClick(View v) {            if (btn.isClickable());             Toast.makeText(MainActivity.this,"再按一次退出按钮",Toast.LENGTH_LONG).show();

}    });

}

public boolean onTouchEvent(MotionEvent event) {    if (event.getAction() == MotionEvent.ACTION_MOVE) {        float x = event.getX();        float y = event.getY();        String pos = "x坐标" + x + "y坐标" + y;        Toast.makeText(this, pos, Toast.LENGTH_LONG).show();        picture.setImageResource(R.drawable.youcaihua);        picture.setX(x - 100);        picture.setY(y - 100);    }    return super.onTouchEvent(event);}

private long exitTime = 0;