时间:2021-02-13 11:11:05 | 栏目:Android代码 | 点击:次
一、回顾
ActivityCollector.java
用于管理所有的活动;一个类是BaseActivity.java
作为所有活动的父类;login.xml
二、登录页面的活动
接下来写一个登录页面的活动,继承自BaseActivity.java
package com.example.broadcastbestpractice; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.widget.Button; import android.widget.EditText; import android.widget.Toast; public class LoginActivity extends BaseActivity{ private EditText accountEdit; private EditText passwordEdit; private Button login; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.login); accountEdit = (EditText)findViewById(R.id.account); passwordEdit = (EditText)findViewById(R.id.password); login = (Button) findViewById(R.id.login); login.setOnClickListener( new OnClickListener() { @Override public void onClick(View v) { String account =accountEdit.getText().toString(); String password = passwordEdit.getText().toString(); //如果账号是admin,密码是12345,就认为登录成功 if(account.contentEquals("admin") && password.equals("12345")) { Intent intent = new Intent(LoginActivity.this,MainActivity.class); startActivity(intent); finish(); }else { Toast.makeText(LoginActivity.this,"account or password is invalid",Toast.LENGTH_SHORT).show(); } } }); } }
findViewById
方法分别获取输入框以及登录按钮的实例<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" > <Button android:id="@+id/force_offline" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="Send force offline broadcast" /> </LinearLayout>
package com.example.broadcastbestpractice; import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.widget.Button; public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); Button forceOffline = (Button) findViewById(R.id.force_offline); forceOffline.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { Intent intent = new Intent("com.example.broadcastbestpractice.FORCE_OFFLINE"); sendBroadcast(intent); } }); } }
com.example.broadcastbestpractice.FORCE_OFFLINE
广播,用于通知程序强制用户下线。package com.example.broadcastbestpractice; import android.app.AlertDialog; import android.app.AlertDialog.Builder; import android.content.BroadcastReceiver; import android.content.Context; import android.content.DialogInterface; import android.content.Intent; import android.view.WindowManager; import android.content.DialogInterface.OnClickListener;; public class ForceOfflineReceiver extends BroadcastReceiver{ @Override public void onReceive(final Context context,Intent intent) { AlertDialog.Builder dialogBuilder = new AlertDialog.Builder(context); dialogBuilder.setTitle("Warning"); dialogBuilder.setMessage("You are forced to be offline,Please try to login again."); dialogBuilder.setCancelable(false); //下面这句改了 dialogBuilder.setPositiveButton("OK", new OnClickListener() { @Override public void onClick(DialogInterface dialog,int which) { ActivityCollector.finishAll();//销毁所有的活动 Intent intent = new Intent(context,LoginActivity.class); intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK); context.startActivity(intent);//重新启动LoginActivity } }); AlertDialog alertDialog = dialogBuilder.create(); //需要设置AlertDialog的类型,保证广播接收器中可以正常弹出 alertDialog.getWindow().setType(WindowManager.LayoutParams.TYPE_SYSTEM_ALERT); alertDialog.show(); } }
25.1
三、源码:
BroadcastBestPractice
https://github.com/ruigege66/Android/tree/master/BroadcastBestPractice