Android悬浮框，在Service中打开悬浮窗；在Service中打开Dialog；

文章介绍了如何在Service中显示悬浮框，在Service中弹出Dialog，在Service中做耗时的轮询操作；

背景需求：

公司的项目现在的逻辑是这样的：发送一个指令，然后3秒一次轮询去查询这个指令是否成功，在这期间界面有遮盖不可操作；

然后需求改了，因为遮盖界面不让用户操作体验不好；现在的需求是：这个轮询查询指令是否成功的操作在后端进行，界面有一个悬浮框用来提示用户正在查询指令；

嗯，在后端查询指令让用户无感，可以用Service实现，然后悬浮框使用WindowMessage实现，轮询查询指令使用Handler或IntentService实现；大致就是这样，先来个Demo；

1、开启服务：需要的信息由Activity使用Intent传递给Service；

Intent intent = new Intent(this,MyService.class);

        intent.putExtra("args","晨");

        startService(intent);

public class MyService extends Service {

    public MyService() {

    }

    @Override

    public IBinder onBind(Intent intent) {

        throw new UnsupportedOperationException("Not yet implemented");

    }

    @Override

    public void onCreate() {

        super.onCreate();

    }

    @Override

    public int onStartCommand(Intent intent, int flags, int startId) {

       args = intent.getStringExtra("args");

        return super.onStartCommand(intent, flags, startId);

    }

    @Override

    public void onDestroy() {

        super.onDestroy();

    }

}

Service中的onCreate只在创建的时候执行一次，onStartCommand()每次开启这个Service都会执行；同时别忘记这个注册：

  <service

            android:name=".MyService"

            android:enabled="true"

            android:exported="true" />

2、在Service开启成功后创建悬浮框，

    @Override

    public int onStartCommand(Intent intent, int flags, int startId) {

       args = intent.getStringExtra("args");

       initView();

        return super.onStartCommand(intent, flags, startId);

    }

 /**

     * 使用系统级别的WindowManager展示悬浮框，需要6.0以上的权限；

     */

    private void initView() {

        if (Build.VERSION.SDK_INT >= 23) {

            if (!Settings.canDrawOverlays(this)) {

                Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION);

                intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

                intent.setData(Uri.parse( "package:"+"com.example.administrator.xuanfudemo"));  //应用的包名，可直接跳转到这个应用的悬浮窗设置；

                startActivity(intent);

            } else {

                openWindow();

            }

        }else {

            openWindow();

        }

    }

    private void openWindow(){

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

        WindowManager.LayoutParams layoutParams = new WindowManager.LayoutParams();

        layoutParams.height = ViewGroup.LayoutParams.WRAP_CONTENT;

        layoutParams.width = ViewGroup.LayoutParams.WRAP_CONTENT;

        layoutParams.type = WindowManager.LayoutParams.TYPE_SYSTEM_ALERT;

//        layoutParams.type = WindowManager.LayoutParams.TYPE_APPLICATION_ATTACHED_DIALOG;

//        layoutParams.token = this.getWindow().getDecorView().getWindowToken();  //这样设置，在activity中打开悬浮框可绕过权限；

        layoutParams.flags =  WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE | WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL;

        layoutParams.format = PixelFormat.TRANSLUCENT;  //透明

        layoutParams.gravity = Gravity.TOP | Gravity.RIGHT;  //右上角显示

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

        windowManager.addView(view,layoutParams);

    }

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

悬浮框需要权限，而且这个权限属于危险级权限，API23以上需要用户手动开启；

3、使用Handler轮询查询指令；

查询到指令后弹框提示，弹出Dialog。在Service中弹出Dialog需要设置下方代码，同时还要有弹窗权限；

dialog.getWindow().setType(WindowManager.LayoutParams.TYPE_SYSTEM_ALERT);

 private Handler mHandler = new Handler(){

        @Override

        public void dispatchMessage(Message msg) {

            super.dispatchMessage(msg);

            switch (msg.what){

                case HANDLERSIGN:

                    Log.i(TAG, "dispatchMessage: "+args+(++num));

                    mHandler.sendEmptyMessageDelayed(HANDLERSIGN,HANDLERTIME);

                    if (num == 5){

                        AlertDialog.Builder builder = new AlertDialog.Builder(MyService.this);

                        builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {

                            @Override

                            public void onClick(DialogInterface dialogInterface, int i) {

                                MyService.this.stopSelf();

                            }

                        });

                        AlertDialog dialog = builder.create();

                        dialog.setMessage("我的计数"+num);

                        dialog.setTitle("提示");

                        dialog.getWindow().setType(WindowManager.LayoutParams.TYPE_SYSTEM_ALERT);

                        dialog.show();

                    }

                    break;

            }

        }

    };

    private final String TAG = "ccb";

    private String args;

    private int num;

    private final int HANDLERSIGN = 10;

    private final int HANDLERTIME = 2010;

    @Override

    public int onStartCommand(Intent intent, int flags, int startId) {

       args = intent.getStringExtra("args");

       initView();

        initData();

        return super.onStartCommand(intent, flags, startId);

    }

  private void initData() {

        mHandler.sendEmptyMessageDelayed(HANDLERSIGN,HANDLERTIME);

    }

4、在服务销毁时，清空Handler信息关闭悬浮框；

    @Override

    public void onDestroy() {

        super.onDestroy();

        Log.i(TAG, "onDestroy: 啊，ByKill");

        mHandler.removeCallbacksAndMessages(null);

        if (windowManager != null) windowManager.removeView(view);

    }

全部的Service代码：

悬浮框我使用了两种，另外一种是FloatWindow，有兴趣的可以去GitHub查一下；

package com.example.administrator.xuanfudemo;

import android.Manifest;

import android.app.AlertDialog;

import android.app.Service;

import android.content.DialogInterface;

import android.content.Intent;

import android.graphics.PixelFormat;

import android.net.Uri;

import android.os.Build;

import android.os.Handler;

import android.os.IBinder;

import android.os.Message;

import android.provider.Settings;

import android.support.v4.app.ActivityCompat;

import android.util.Log;

import android.view.Gravity;

import android.view.LayoutInflater;

import android.view.View;

import android.view.ViewGroup;

import android.view.WindowManager;

import com.yhao.floatwindow.FloatWindow;

import com.yhao.floatwindow.PermissionListener;

import com.yhao.floatwindow.Screen;

import com.yhao.floatwindow.ViewStateListener;

public class MyService extends Service {

    private WindowManager windowManager;

    private View view;

    public MyService() {

    }

    @Override

    public IBinder onBind(Intent intent) {

        throw new UnsupportedOperationException("Not yet implemented");

    }

    @Override

    public void onCreate() {

        super.onCreate();

    }

    private Handler mHandler = new Handler(){

        @Override

        public void dispatchMessage(Message msg) {

            super.dispatchMessage(msg);

            switch (msg.what){

                case HANDLERSIGN:

                    Log.i(TAG, "dispatchMessage: "+args+(++num));

                    mHandler.sendEmptyMessageDelayed(HANDLERSIGN,HANDLERTIME);

                    if (num == 5){

                        AlertDialog.Builder builder = new AlertDialog.Builder(MyService.this);

                        builder.setPositiveButton("确定", new DialogInterface.OnClickListener() {

                            @Override

                            public void onClick(DialogInterface dialogInterface, int i) {

                                MyService.this.stopSelf();

//                                if (windowManager != null) windowManager.removeView(view);

                            }

                        });

                        AlertDialog dialog = builder.create();

                        dialog.setMessage("我的计数"+num);

                        dialog.setTitle("提示");

                        dialog.getWindow().setType(WindowManager.LayoutParams.TYPE_SYSTEM_ALERT);

                        dialog.show();

                    }

                    break;

            }

        }

    };

    private final String TAG = "ccb";

    private String args;

    private int num;

    private final int HANDLERSIGN = 10;

    private final int HANDLERTIME = 2010;

    @Override

    public int onStartCommand(Intent intent, int flags, int startId) {

       args = intent.getStringExtra("args");

//       initView();

       initView2();

        initData();

        return super.onStartCommand(intent, flags, startId);

    }

    /**

     * FloatWindow使用FloatWindow库展示悬浮框；可拖拽

     */

    private void initView2() {

        FloatWindow

                .with(getApplicationContext())

                .setView(LayoutInflater.from(this).inflate(R.layout.view_win,null))

                .setWidth(100)                               //设置控件宽高

                .setHeight(Screen.height,0.2f)

                .setX(100)                                   //设置控件初始位置

                .setY(Screen.height,0.3f)

                .setDesktopShow(true)                        //桌面显示

                .setViewStateListener(new ViewStateListener() {

                    @Override

                    public void onPositionUpdate(int i, int i1) {

                    }

                    @Override

                    public void onShow() {

                    }

                    @Override

                    public void onHide() {

                    }

                    @Override

                    public void onDismiss() {

                    }

                    @Override

                    public void onMoveAnimStart() {

                    }

                    @Override

                    public void onMoveAnimEnd() {

                    }

                    @Override

                    public void onBackToDesktop() {

                    }

                })

                .setPermissionListener(new PermissionListener() {

                    @Override

                    public void onSuccess() {

                    }

                    @Override

                    public void onFail() {

                    }

                })

                .build();

        FloatWindow.get().show();

    }

    /**

     * 使用系统级别的WindowManager展示悬浮框，需要6.0以上的权限；

     */

    private void initView() {

        if (Build.VERSION.SDK_INT >= 23) {

            if (!Settings.canDrawOverlays(this)) {

                Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION);

                intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

                intent.setData(Uri.parse( "package:"+"com.example.administrator.xuanfudemo"));

                startActivity(intent);

            } else {

                openWindow();

            }

        }else {

            openWindow();

        }

    }

    private void openWindow(){

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

        WindowManager.LayoutParams layoutParams = new WindowManager.LayoutParams();

        layoutParams.height = ViewGroup.LayoutParams.WRAP_CONTENT;

        layoutParams.width = ViewGroup.LayoutParams.WRAP_CONTENT;

        layoutParams.type = WindowManager.LayoutParams.TYPE_SYSTEM_ALERT;

//        layoutParams.type = WindowManager.LayoutParams.TYPE_APPLICATION_ATTACHED_DIALOG;

//        layoutParams.token = this.getWindow().getDecorView().getWindowToken();

        layoutParams.flags =  WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE | WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL;

        layoutParams.format = PixelFormat.TRANSLUCENT;

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

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

        windowManager.addView(view,layoutParams);

    }

    private void initData() {

        mHandler.sendEmptyMessageDelayed(HANDLERSIGN,HANDLERTIME);

    }

    @Override

    public void onDestroy() {

        super.onDestroy();

        Log.i(TAG, "onDestroy: 啊，ByKill");

        mHandler.removeCallbacksAndMessages(null);

        if (windowManager != null) windowManager.removeView(view);

        FloatWindow.destroy();

    }

}