broadcastreceiver

问题 I have to develop an app locker for Android where the user can block apps and other users can not access these apps without an access key. I have installed an app but I don't know how to lock this app. Please suggest me something. 回答1: This is not how stack overflow works. You can not ask a complete solution without even trying anything. For the most basic version of your app, you need to perform three functions. Get a list of all the installed apps on device and show them in a ListView with

问题 I have to get the WiFi ssid whenever phone connects to new WiFi network. I registered the following receiver `registerReceiver(this.mybroadcast, new IntentFilter(WifiManager.SUPPLICANT_CONNECTION_CHANGE_ACTION));` This part of code works perfectly. But in onReceive method, NetworkInfo info = intent.getParcelableExtra(WifiManager.EXTRA_WIFI_INFO)); always returns null. I tried EXTRA_NETWORK_INFO as well, but it also returns Null. I can't use this.registerReceiver(this.mybroadcast, new

问题 Problem: I am willing to create an application that simply starts as a background process and whenever a new message comes into the device it should log it into a file or simply display a toast message. I have read a lot of blogs and tried to follow the steps as mentioned. But, I keep on sending messages on my device and nothing displayed not even in device log. I want to run it on devices from Froyo to Lollipop. So, I am not willing to use new Telephony API which supports API 19 and later

问题 In android, you can set the action of a broadcast to almost anything (save system actions.) My question is how can you prevent other apps from spoofing your broadcasts? Say you have an action called "com.a.b.c". Other applications should receive com.a.b.c, but they shouldn't be able to send com.a.b.c. How can that be done? Also, I seek clarification of permissions that deal with broadcast reception. I find the Android documentation a bit confusing with this. Is there a way to make a

问题 I am working on an app in which i need to log, if user uninstalls the app. So i am following this approach How can an app detect that it's going to be uninstalled? But i am facing the same problem as in this post Can't get receiver when the app uninstall. As my phone is Android 4.4... Can anybody post the exact solution (code) to solve this problem??? Edit: During uninstallation QUERY_PACKAGE_RESTART intent should be broadcasted but i am not recieving it. I declared it in manifest as well i

问题 I create an birthday reminder app. I want to start service at 12:00 in night to scan birthdays of person in Database. I add a broadcast receiver. <receiver android:name=".MyReceiver"> <intent-filter> <action android:name="android.intent.action.DATE_CHANGED"/> </intent-filter> </receiver> But It don't work. I don't why.. here is the code of broadcast receiver ..... package com.example.forgetmenot; import android.content.BroadcastReceiver; import android.content.Context; import android.content

问题 I'm developing an application which will consists only of a few services and no activities (i.e. no UI) Basically I want to have 2 to 3 services to be running in the background right from when user installs the application on his/her device. I have a few questions over this: How will my services start after application installation? My BroadcastReceiver should be listening to which event? How can I package my application to deploy it application on Googly Play Store? 回答1: You can't do that on

问题 I'm trying to display information got from wifi scan with broadcast receiver ,into a bar chart using achartengine. Well i want to have a real time chart ,every time i receive data from onReceive() method ,i update the chart. To achaeive that ,i create the chart objects in the onReceive() method .But i just get a chart with the first result ,there is no update ,although i can see the changes on the wifi scan. I would like to know what is the problem. This is the code that i'm using: public

问题 I am not quite certain what the behavior of a BroadcastReceiver , registered in the manifest and enabled via PackageManager , is when the phone is asleep. The question arose because I need a receiver registered for broadcasts from WifiManager <receiver android:name=".receivers.ScanResultsReceiver" android:enabled="false" > <intent-filter> <action android:name="android.net.wifi.SCAN_RESULTS" /> <action android:name="android.net.wifi.WIFI_STATE_CHANGED" /> </intent-filter> </receiver> but what

问题 I stumbled about a problem to receive GCM messages if my app runs in background (Service). In my scenario, I don't receive the GCM message (please notice it is not about how to receive GCM in general like here) and the ActivityManager kills the app. So I wonder if I have a conceptual misunderstanding or if it is a general problem. Background I have an Android application that runs in foreground (Activity) and background (Service). The application is attached to a persistent notification to