Question

我已经编写了一个小程序，可以在来电时打开相机闪光灯LED。它第一次运行良好，但第二次应用程序崩溃。而现在该应用程序将无法运行。我甚至重新安装了应用程序！我正在使用TelephonyManager和PhoneStateListener。任何人都可以表明该计划有什么问题吗？已经超过一个小时了，我一点都不知道！任何帮助将不胜感激。

这是清单声明：

    <?xml version="1.0" encoding="utf-8"?>
    <manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.firefly"
    android:versionCode="1"
    android:versionName="1.0">
    <uses-sdk android:minSdkVersion="14" />
    <uses-permission android:name="android.permission.READ_PHONE_STATE"/>
    <uses-permission android:name="android.permission.CAMERA" />

    <uses-feature android:name="android.hardware.camera" />

    <application android:icon="@drawable/ic_launcher" android:label="Firefly">

        <receiver android:name="MainActivity">
            <intent-filter>
                 <action android:name="android.intent.action.PHONE_STATE"/>
            </intent-filter>
        </receiver>

    </application>

</manifest>

实际代码：

package com.firefly;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.hardware.Camera;
import android.hardware.Camera.Parameters;
import android.telephony.PhoneStateListener;
import android.telephony.TelephonyManager;
import android.util.Log;
import android.widget.Toast;

public class MainActivity extends BroadcastReceiver {

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

        try {
            TelephonyManager tmgr = (TelephonyManager) context
                    .getSystemService(Context.TELEPHONY_SERVICE);

            // Create Listener
            MyPhoneStateListener PhoneListener = new MyPhoneStateListener(context);

            // Register listener for LISTEN_CALL_STATE
            tmgr.listen(PhoneListener, PhoneStateListener.LISTEN_CALL_STATE);

        } catch (Exception e) {
            Log.e("Phone Receive Error", " " + e);
        }

    }

    private class MyPhoneStateListener extends PhoneStateListener {

        private Context ctx;
        private boolean flashavailable;
        private Camera camera;

        private MyPhoneStateListener(Context ctx) {
            this.ctx=ctx;
        }

        public void onCallStateChanged(int state, String incomingNumber) {

            flashavailable=ctx.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH);

            if (state == TelephonyManager.CALL_STATE_RINGING) {             
                if (flashavailable){
                    //Turning on the flash LED
                    camera = Camera.open();
                    final Parameters p = camera.getParameters();
                    p.setFlashMode(Parameters.FLASH_MODE_TORCH);
                    camera.setParameters(p);
                    camera.startPreview();
                }
                String msg = "New Phone Call Event. Incomming Number : "+incomingNumber;
                Toast.makeText(ctx, msg, Toast.LENGTH_LONG).show();
            }
        }
    }
}

Android PhoneStateListener无法在广播接收器内工作

0 个答案: