悬在activity之上的组件，但不影响activity的操作

如果设置在服务中，不移除的话，可以显示在任何界面

实现如图：你好

public void showAddressTip(String number) {

// TN的构造方法(参考Toast的源码)

final LayoutParams params = new WindowManager.LayoutParams();

//设置宽高为WrapContent

params.height = WindowManager.LayoutParams.WRAP_CONTENT;

params.width = WindowManager.LayoutParams.WRAP_CONTENT;

//半透明

params.format = PixelFormat.TRANSLUCENT;

//类型为Toast

// TYPE_PRIORITY_PHONE优先于通话界面权限:android.permission.SYSTEM_ALERT_WINDOW

// Android保护机制:在通话的时候,通话界面优先级最高其他界面都不可被触摸

params.type = WindowManager.LayoutParams.TYPE_PRIORITY_PHONE;

params.flags = WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON //保持屏幕常量

| WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE; //不可获取焦点

//焦点和触摸事件没有任何关系

// |WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE; //客官不可摸

//加载布局

final TextView tvAddress = (TextView) View.inflate(MyServicer.this,

R.layout.tip_address, null);

//设置内容

tvAddress.setText(number);

tvAddress.setBackgroundResource(android.R.color.holo_green_light);

//获取WindowManager

final WindowManager mWm = (WindowManager) getSystemService(Context.WINDOW_SERVICE);

//通过WindowManager添加一个控件最终控件会显示在Window上

mWm.addView(tvAddress, params);

tvAddress.setOnTouchListener(new OnTouchListener() {

private int downX;

private int downY;

@Override

public boolean onTouch(View v, MotionEvent event) {

switch (event.getAction()) {

case MotionEvent.ACTION_DOWN:

Log.i("test", "down");

//获取当前点击下去的位置

downX = (int) event.getRawX();

downY = (int) event.getRawY();

break;

case MotionEvent.ACTION_MOVE:

Log.i("test", "move");

//获取X和Y的偏移量

int moveX = (int) event.getRawX();

int moveY = (int) event.getRawY();

//计算差值

int dx = moveX - downX;

int dy = moveY - downY;

//在原来的基础上加上现在移动的差值

params.x = params.x + dx;

params.y = params.y + dy;

//更新控件参数布局

mWm.updateViewLayout(tvAddress, params);

downX = moveX;

downY = moveY;

break;

case MotionEvent.ACTION_UP:

Log.i("test", "up");

break;

default:

break;

}

return false;

}

});

}