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安卓开发_广播机制_广播的最佳实践:实现强制下线功能
简介安卓开发_广播机制_广播的最佳实践:实现强制下线功能
安卓开发_广播机制_广播的最佳实践:实现强制下线功能
ActivityCollector类用于管理所有的Activity
object ActivityCollector {
private val activities = ArrayList<Activity>()
fun addActivity(activity: Activity) {
activities.add(activity)
}
fun removeActivity(activity: Activity) {
activities.remove(activity)
}
fun finishAll() {
for (activity in activities) {
if (!activity.isFinishing) {
activity.finish()
}
}
activities.clear()
}
}
BaseActivity类作为所有Activity的父类
open class BaseActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
ActivityCollector.addActivity(this)
}
override fun onDestroy() {
super.onDestroy()
ActivityCollector.removeActivity(this)
}
}
创建一个LoginActivity来作为登录界面
布局
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="60dp">
<TextView
android:layout_width="90dp"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:textSize="18sp"
android:text="Account:" />
<EditText
android:id="@+id/accountEdit"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:layout_gravity="center_vertical" />
</LinearLayout>
<LinearLayout
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="60dp">
<TextView
android:layout_width="90dp"
android:layout_height="wrap_content"
android:layout_gravity="center_vertical"
android:textSize="18sp"
android:text="Password:" />
<EditText
android:id="@+id/passwordEdit"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:layout_gravity="center_vertical"
android:inputType="textPassword" />
</LinearLayout>
<Button
android:id="@+id/login"
android:layout_width="200dp"
android:layout_height="60dp"
android:layout_gravity="center_horizontal"
android:text="Login" />
</LinearLayout>
LoginActivity
class LoginActivity : AppCompatActivity() {
private lateinit var binding: ActivityLoginBinding
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
binding = ActivityLoginBinding.inflate(layoutInflater)
setContentView(binding.root)
binding.login.setOnClickListener {
val account = binding.accountEdit.text.toString()
val password = binding.passwordEdit.text.toString()
if(account == "admin" && password == "123456"){
val intent = Intent(this, MainActivity::class.java)
startActivity(intent)
finish()
}else{
Toast.makeText(this, "account or password is invaild", Toast.LENGTH_SHORT).show()
}
}
}
}
在MainActivity中加入强制下线功能
布局
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<Button
android:id="@+id/forceOffline"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Send force offline broadcast" />
</LinearLayout>
MainActivity
class MainActivity : BaseActivity() {
private lateinit var binding: ActivityMainBinding
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
binding = ActivityMainBinding.inflate(layoutInflater)
setContentView(binding.root)
binding.forceOffline.setOnClickListener {
val intent = Intent("com.example.broadcastbestpractice.FORCE_OFFLINE")
sendBroadcast(intent)
}
}
}
在BaseActivity中注册广播接收
open class BaseActivity : AppCompatActivity() {
private lateinit var receiver: ForceOfflineReceiver
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
ActivityCollector.addActivity(this)
}
override fun onResume() {
super.onResume()
val intentFilter = IntentFilter()
intentFilter.addAction("com.example.broadcastbestpractice.FORCE_OFFLINE")
receiver = ForceOfflineReceiver()
registerReceiver(receiver, intentFilter)
}
override fun onPause() {
super.onPause()
unregisterReceiver(receiver)
}
override fun onDestroy() {
super.onDestroy()
ActivityCollector.removeActivity(this)
}
inner class ForceOfflineReceiver: BroadcastReceiver(){
override fun onReceive(context: Context, intent: Intent) {
AlertDialog.Builder(context).apply{
setTitle("Warining")
setMessage("You are forced to be offline. Please try to login again.")
setCancelable(false)
setPositiveButton("OK") { _, _ ->
ActivityCollector.finishAll()
val i = Intent(context, LoginActivity::class.java)
context.startActivity(i)
}
show()
}
}
}
}
将LoginActivity注册为主Activity
参考
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