Android系统开发 添加自定义的系统全局广播

版权声明

本文来自博客园，作者：观心静 ，转载请注明原文链接：https://www.cnblogs.com/guanxinjing/p/17890899.html

本文版权归作者和博客园共有，欢迎转载，但必须给出原文链接，并保留此段声明，否则保留追究法律责任的权利。

前言

  此博客基于Android10版本讲解如何在系统中添加自定义的系统全局广播。下面通过一个发送按键广播的例子在说明

例子：发送按键广播

系统广播添加位置

修改文件路径：/aosp/frameworks/base/core/res/AndroidManifest.xml

在PhoneWindowManager中添加发送广播的代码

修改文件路径：/aosp/frameworks/base/services/core/java/com/android/server/policy/PhoneWindowManager.java

在PhoneWindowManager的interceptKeyBeforeQueueing方法中添加下面注释中的代码

@Override
    public int interceptKeyBeforeQueueing(KeyEvent event, int policyFlags) {
        if (!mSystemBooted) {
            // If we have not yet booted, don't let key events do anything.
            return 0;
        }

        final boolean interactive = (policyFlags & FLAG_INTERACTIVE) != 0;
        final boolean down = event.getAction() == KeyEvent.ACTION_DOWN;
        final boolean canceled = event.isCanceled();
        final int keyCode = event.getKeyCode();
        final int displayId = event.getDisplayId();

        final boolean isInjected = (policyFlags & WindowManagerPolicy.FLAG_INJECTED) != 0;

        //略..........

        // If the key would be handled globally, just return the result, don't worry about special
        // key processing.
        if (isValidGlobalKey(keyCode)
                && mGlobalKeyManager.shouldHandleGlobalKey(keyCode, event)) {
            if (isWakeKey) {
                wakeUp(event.getEventTime(), mAllowTheaterModeWakeFromKey,
                        PowerManager.WAKE_REASON_WAKE_KEY, "android.policy:KEY");
            }
            return result;
        }

        // Enable haptics if down and virtual key without multiple repetitions. If this is a hard
        // virtual key such as a navigation bar button, only vibrate if flag is enabled.
        final boolean isNavBarVirtKey = ((event.getFlags() & KeyEvent.FLAG_VIRTUAL_HARD_KEY) != 0);
        boolean useHapticFeedback = down
                && (policyFlags & WindowManagerPolicy.FLAG_VIRTUAL) != 0
                && (!isNavBarVirtKey || mNavBarVirtualKeyHapticFeedbackEnabled)
                && event.getRepeatCount() == 0;
        //===============在此处添加要发送的按键广播
        Intent devKeyIntent = new Intent();
        if (down) {
            devKeyIntent.setAction("com.zhou.action.DEV_KEY_DOWN");
        } else {
            devKeyIntent.setAction("com.zhou.action.DEV_KEY_UP");
        }
        devKeyIntent.putExtra("keyCode", keyCode);
        mContext.sendBroadcast(devKeyIntent);
        //================

        // Handle special keys.
        switch (keyCode) {
            case KeyEvent.KEYCODE_BACK: {
                if (down) {
                    interceptBackKeyDown();
                } else {
                    boolean handled = interceptBackKeyUp(event);

                    // Don't pass back press to app if we've already handled it via long press
                    if (handled) {
                        result &= ~ACTION_PASS_TO_USER;
                    }
                }
                break;
            }
        //略..............

在自己的应用中注册并且接收广播

 在Activity中注册并且接收广播

class MainActivity : AppCompatActivity() {
    lateinit var mReceiver: DevKeyReceiver

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        //注册广播
        val intentFilter = IntentFilter()
        intentFilter.addAction("com.zhou.action.DEV_KEY_UP")
        intentFilter.addAction("com.zhou.action.DEV_KEY_DOWN")
        mReceiver = DevKeyReceiver()
        registerReceiver(mReceiver, intentFilter)
    }

    override fun onDestroy() {
        super.onDestroy()
        //注销广播
        unregisterReceiver(mReceiver)
    }
}

class DevKeyReceiver : BroadcastReceiver() {
    override fun onReceive(context: Context, intent: Intent) {
        Log.e("zh", "接受广播 action = ${intent.action}   keyCode = ${intent.getIntExtra("keyCode", -1)}")
        Toast.makeText(context, "接受广播 action = ${intent.action}   keyCode = ${intent.getIntExtra("keyCode", -1)}", Toast.LENGTH_SHORT).show()
    }
}

效果图

这里可以通过adb命令发送各种键值以达到测试目的，例如adb shell input keyevent 24 音量加  和  adb shell input keyevent 25  音量减  

 

 

end