实现简单锁屏

1

package example.com.locker.service;

import android.app.KeyguardManager;
import android.app.Service;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.IBinder;
import android.util.Log;
import android.widget.Toast;

import example.com.locker.activity.LockActivity;


public class LockService extends Service {


    private final  String TAG="mylock";

    public LockService() {

    }

    private Intent mIntent;

    @Override
    public IBinder onBind(Intent intent) {
        return  null;
    }

    private BroadcastReceiver mScreenOnReceiver=new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {

            String action=intent.getAction();

            Log.d("mylock",action);
            if(action.equals(Intent.ACTION_SCREEN_ON)
                    ||action.equals(Intent.ACTION_SCREEN_OFF))
            {
                km=(KeyguardManager)context.getSystemService(Context.KEYGUARD_SERVICE);
                kl=km.newKeyguardLock("");
                kl.disableKeyguard();
                startActivity(mIntent);
            }
        }
    };

    KeyguardManager km;
    KeyguardManager.KeyguardLock kl;


    @Override
    public void onCreate() {
        super.onCreate();

        Toast.makeText(this,"lock 服务启动",Toast.LENGTH_SHORT).show();

        mIntent=new Intent(LockService.this, LockActivity.class);
        mIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

        IntentFilter mScreenOnFilter=new IntentFilter();
        mScreenOnFilter.addAction("android.intent.action.SCREEN_ON");
        mScreenOnFilter.addAction("android.intent.action.SCREEN_OFF");

       registerReceiver(mScreenOnReceiver,mScreenOnFilter);

    }


    @Override
    public void onDestroy() {
        super.onDestroy();
        Log.d(TAG,"服务终止");
        this.unregisterReceiver(mScreenOnReceiver);
        //被销毁时启动自身，保持在后台存活
        startService(new Intent(this,LockService.class));
    }


}

package example.com.locker.activity;

import android.app.Activity;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Button;

import example.com.locker.R;
import example.com.locker.view.LockLayer;

public class LockActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        //全屏显示
        this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);


        setContentView(R.layout.activity_lock);
        Button unlockButton=(Button)findViewById(R.id.unlock);
        unlockButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                finish();
            }
        });
    }


    //屏蔽音量键,返回键
    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        switch (event.getKeyCode())
        {
            case KeyEvent.KEYCODE_BACK:
            case  KeyEvent.KEYCODE_VOLUME_DOWN:
            case  KeyEvent.KEYCODE_VOLUME_UP:
                return true;
        }
        return super.onKeyDown(keyCode,event);
    }

}

屏蔽系统本身锁屏，需要权限<uses-permission android:name="android.permission.DISABLE_KEYGUARD" />

监听开机广播，需要权限<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED" />

监听开机广播

package example.com.locker.service;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.util.Log;
import android.widget.Toast;

import example.com.locker.activity.CardActivity;

public class BootReceiver extends BroadcastReceiver {

    public BootReceiver() {

    }

    @Override
    public void onReceive(Context context, Intent intent) {

            Intent serviceIntent=new Intent(context,LockService.class);
            context.startService(serviceIntent);
            Toast.makeText(context,"开启启动",Toast.LENGTH_SHORT).show();

    }
}

监听屏幕 SCREEN_ON 和 SCREEN_OFF 这两个 action 只能通过代码注册才能监听到，不能再Manifest.xml文件中给出

 <receiver
            android:name=".service.BootReceiver"
            android:enabled="true"
            android:exported="true" >
            <intent-filter>
                <action android:name="android.intent.action.BOOT_COMPLETED"/>
            </intent-filter>
        </receiver>