Android中加入悬浮窗

悬浮窗可以一直在前台显示一些信息，无论当前的Activity是哪个应用的。比如显示当前的上下行网速等

import android.app.Service;

import android.content.BroadcastReceiver;

import android.content.Context;

import android.content.Intent;

import android.graphics.PixelFormat;

import android.graphics.Rect;

import android.os.IBinder;

import android.view.Gravity;

import android.view.LayoutInflater;

import android.view.MotionEvent;

import android.view.View;

import android.view.WindowManager;

import android.view.View.OnTouchListener;

import android.view.WindowManager.LayoutParams;

/**

* 悬浮窗Service 该服务会在后台一直运行一个悬浮的透明的窗体。

*

* @author

*

*/

public class FloatingService extends Service {

private int statusBarHeight;// 状态栏高度

private View view;// 透明窗体

private boolean viewAdded = false;// 透明窗体是否已经显示

private WindowManager windowManager;

private WindowManager.LayoutParams layoutParams;

@Override

public IBinder onBind(Intent intent) {

return null;

}

@Override

public void onCreate() {

super.onCreate();

view = LayoutInflater.from(this).inflate(R.layout.floating, null);

windowManager = (WindowManager) this.getSystemService(WINDOW_SERVICE);

/*

* LayoutParams.TYPE_SYSTEM_ERROR：保证该悬浮窗所有View的最上层

* LayoutParams.FLAG_NOT_FOCUSABLE:该浮动窗不会获得焦点，但可以获得拖动

* PixelFormat.TRANSPARENT：悬浮窗透明

*/

layoutParams = new LayoutParams(LayoutParams.WRAP_CONTENT,

LayoutParams.WRAP_CONTENT, LayoutParams.TYPE_SYSTEM_ERROR,

LayoutParams.FLAG_NOT_FOCUSABLE, PixelFormat.TRANSPARENT);

// layoutParams.gravity = Gravity.RIGHT|Gravity.BOTTOM; //悬浮窗开始在右下角显示

layoutParams.gravity = Gravity.LEFT | Gravity.TOP;

view.setOnTouchListener(new OnTouchListener() {

float[] temp = new float[] { 0f, 0f };

public boolean onTouch(View v, MotionEvent event) {

layoutParams.gravity = Gravity.LEFT | Gravity.TOP;

int eventaction = event.getAction();

switch (eventaction) {

case MotionEvent.ACTION_DOWN: // 按下事件，记录按下时手指在悬浮窗的XY坐标值

temp[0] = event.getX();

temp[1] = event.getY();

break;

case MotionEvent.ACTION_MOVE:

refreshView((int) (event.getRawX() - temp[0]), (int) (event

.getRawY() - temp[1]));

break;

}

return true;

}

});

}

/**

* 刷新悬浮窗

*

* @param x

* 拖动后的X轴坐标

* @param y

* 拖动后的Y轴坐标

*/

public void refreshView(int x, int y) {

//状态栏高度不能立即取，不然得到的值是0

if(statusBarHeight == 0){

View rootView = view.getRootView();

Rect r = new Rect();

rootView.getWindowVisibleDisplayFrame(r);

statusBarHeight = r.top;

}

layoutParams.x = x;

// y轴减去状态栏的高度，因为状态栏不是用户可以绘制的区域，不然拖动的时候会有跳动

layoutParams.y = y - statusBarHeight;//STATUS_HEIGHT;

refresh();

}

/**

* 添加悬浮窗或者更新悬浮窗 如果悬浮窗还没添加则添加 如果已经添加则更新其位置

*/

private void refresh() {

if (viewAdded) {

windowManager.updateViewLayout(view, layoutParams);

} else {

windowManager.addView(view, layoutParams);

viewAdded = true;

}

}

@Override

public void onStart(Intent intent, int startId) {

super.onStart(intent, startId);

refresh();

}

/**

* 关闭悬浮窗

*/

public void removeView() {

if (viewAdded) {

windowManager.removeView(view);

viewAdded = false;

}

}

@Override

public void onDestroy() {

super.onDestroy();

removeView();

}

class StatusBarReceiver extends BroadcastReceiver{

@Override

public void onReceive(Context context, Intent intent) {

//intent.get

}

}

}

floating.xml

<?xml version="1.0" encoding="UTF-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

android:orientation="horizontal"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

>

<!-- android:updatePeriodMillis="10000"> -->

<LinearLayout

android:orientation="horizontal"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:background="@drawable/floating"

android:gravity="center_vertical"

>

<ImageView

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_weight="0.5"

android:src="http://blog.163.com/hero_213/blog/@drawable/upload"/>

<TextView

android:id="@+id/flowing"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_weight="0.5"

android:gravity="right"

android:text="0K/s"

android:textColor="#000000"

/>

<ImageView

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_weight="0.5"

android:src="http://blog.163.com/hero_213/blog/@drawable/download"/>

<TextView

android:gravity="right"

android:id="@+id/flowspeed"

android:paddingRight="10.0dip"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_weight="0.5"

android:text="17K/s"

android:textColor="#000000"

/>

</LinearLayout>

<ImageButton

android:id="@+id/floating_button_hide"

android:background="@drawable/floatingwindowhidebutton"

android:visibility="gone"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

style="\?android:buttonStyleSmall" />

</LinearLayout>

最后还要在AndroidManifest.xml加一个权限

<!-- 悬浮窗(FloatingService) permission -->

<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />