在项目中，我们的应用经常会遇到崩溃的情况，如果你的项目已经发送到了应用市场上，那么应用发生的崩溃开发人员是开不到的，所以我们要想办法将异常信息传到服务器上，便于开发人员查看并作出修改。Google考虑到这一点，也提供了Thread.UncaughtExceptionHandler接口来实现这一问题。
创建Crash异常捕获很简单，主要的步骤有：
1.创建BaseApplication继承Application并实现Thread.UncaughtExceptionHandler
2.通过Thread.setDefaultUncaughtExceptionHandler(this)设置默认的异常捕获
3.最后在manifests中注册创建的BaseApplication
一、异常捕捉的简单实用
public class BaseApplication extends Application implements Thread.UncaughtExceptionHandler {
@Override
public void onCreate() {
super.onCreate();
//设置异常捕获
CrashHandler catchHandler = CrashHandler.getInstance();
catchHandler.init(this);
}
}
二、CrashHandler（主要是实现uncaughtException方法）
public class CrashHandler implements UncaughtExceptionHandler {
public static final String TAG = "CrashHandler";
// 系统默认的UncaughtException处理类
private Thread.UncaughtExceptionHandler mDefaultHandler;
// CrashHandler实例
private static CrashHandler instance;
// 程序的Context对象
private Context mContext;
// 用来存储设备信息和异常信息
private Map<String, String> infos = new HashMap<String, String>();
// 用于格式化日期,作为日志文件名的一部分
private DateFormat formatter = new SimpleDateFormat("yyyy-MM-dd-HH-mm-ss");
MyActivityLifecycleCallbacks mMyActivityLifecycleCallbacks = new MyActivityLifecycleCallbacks();
/** 保证只有一个CrashHandler实例 */
private CrashHandler() {
}
/** 获取CrashHandler实例 ,单例模式 */
public static CrashHandler getInstance() {
if (instance == null)
instance = new CrashHandler();
return instance;
}
/**
* 初始化
*/
public void init(SspApplication context) {
mContext = context;
context.registerActivityLifecycleCallbacks(mMyActivityLifecycleCallbacks);
// 获取系统默认的UncaughtException处理器
mDefaultHandler = Thread.getDefaultUncaughtExceptionHandler();
// 设置该CrashHandler为程序的默认处理器
Thread.setDefaultUncaughtExceptionHandler(this);
}
/**
* 当UncaughtException发生时会转入该函数来处理
*/
@Override
public void uncaughtException(Thread thread, Throwable ex) {
if (!handleException(ex) && mDefaultHandler != null) {
// 如果用户没有处理则让系统默认的异常处理器来处理
mDefaultHandler.uncaughtException(thread, ex);
} else {
// try {
// Thread.sleep(3000);
// } catch (InterruptedException e) {
// Log.e(TAG, "error : ", e);
// }
// 注意Thread.sleep(3000)和 SystemClock.sleep(3000)的区别
SystemClock.sleep(3000);
// 退出程序
Log.i("=====killProcess======","=====killProcess======");
mMyActivityLifecycleCallbacks.removeAllActivities();
android.os.Process.killProcess(android.os.Process.myPid());
System.exit(0);
}
}
/**
* 自定义错误处理,收集错误信息 发送错误报告等操作均在此完成.
*
* @param ex
* @return true:如果处理了该异常信息;否则返回false.
*/
private boolean handleException(Throwable ex) {
Log.i("=====handleException======","=====handleException======");
if (ex == null) {
return false;
}
// 收集设备参数信息
collectDeviceInfo(mContext);
// 使用Toast来显示异常信息
new Thread() {
@Override
public void run() {
Looper.prepare();
Toast.makeText(mContext, "哎呀，出问题了，我要暂时离开了", Toast.LENGTH_SHORT).show();
Looper.loop();
}
}.start();
// 保存日志文件
saveCatchInfo2File(ex);
return true;
}
/**
* 收集设备参数信息
*
* @param ctx
*/
public void collectDeviceInfo(Context ctx) {
try {
PackageManager pm = ctx.getPackageManager();
PackageInfo pi = pm.getPackageInfo(ctx.getPackageName(), PackageManager.GET_ACTIVITIES);
if (pi != null) {
String versionName = pi.versionName == null ? "null" : pi.versionName;
String versionCode = pi.versionCode + "";
infos.put("versionName", versionName);
infos.put("versionCode", versionCode);
}
} catch (NameNotFoundException e) {
Log.e(TAG, "an error occured when collect package info", e);
}
Field[] fields = Build.class.getDeclaredFields();
for (Field field : fields) {
try {
field.setAccessible(true);
infos.put(field.getName(), field.get(null).toString());
Log.d(TAG, field.getName() + " : " + field.get(null));
} catch (Exception e) {
Log.e(TAG, "an error occured when collect crash info", e);
}
}
}
/**
* 保存错误信息到文件中
*
* @param ex
* @return 返回文件名称,便于将文件传送到服务器
*/
private String saveCatchInfo2File(Throwable ex) {
StringBuffer sb = new StringBuffer();
for (Map.Entry<String, String> entry : infos.entrySet()) {
String key = entry.getKey();
String value = entry.getValue();
sb.append(key + "=" + value + "\n");
}
Writer writer = new StringWriter();
PrintWriter printWriter = new PrintWriter(writer);
ex.printStackTrace(printWriter);
Throwable cause = ex.getCause();
while (cause != null) {
cause.printStackTrace(printWriter);
cause = cause.getCause();
}
printWriter.close();
String result = writer.toString();
sb.append(result);
try {
long timestamp = System.currentTimeMillis();
String time = formatter.format(new Date());
SharedPreferences userInfo = mContext.getSharedPreferences(
Constants.USER_SETTING_INFOS, 0);
String loginName = userInfo.getString(Constants.USERNAME, "");
String fileName = "crash-" + time +"-"+loginName+ ".log";
if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {
String path = "/mnt/sdcard/crash/";
File dir = new File(path);
if (!dir.exists()) {
dir.mkdirs();
}
FileOutputStream fos = new FileOutputStream(path + fileName);
fos.write(sb.toString().getBytes());
// 发送给开发人员
sendCrashLog2PM(path + fileName);
fos.close();
}
return fileName;
} catch (Exception e) {
Log.e(TAG, "an error occured while writing file...", e);
}
return null;
}
/**
* 将捕获的导致崩溃的错误信息发送给开发人员
*
* 目前只将log日志保存在sdcard 和输出到LogCat中，并未发送给后台。
*/
private void sendCrashLog2PM(final String fileName) {
if (!new File(fileName).exists()) {
Toast.makeText(mContext, "日志文件不存在！", Toast.LENGTH_SHORT).show();
return;
} else {
new Thread(new Runnable() {
@Override
public void run() {
Looper.prepare();
ArrayList<String> picList = new ArrayList<String>();
picList.add(fileName);
SendEventPic sFile = new SendEventPic(mContext);
UUIDGenerator generator = new UUIDGenerator();
String linkId = generator.generate().toString();
SharedPreferences userInfo = mContext.getSharedPreferences(
Constants.USER_SETTING_INFOS, 0);
String loginName = userInfo.getString(Constants.USERNAME, "");
String userId = userInfo.getString(Constants.USER_USERID_INFOS, "");
boolean isproblempic = sFile.isSendSuccess(picList, linkId,
"crash_tng", "crash_tng", loginName, userId);
Looper.loop();
}
}).start();
}
FileInputStream fis = null;
BufferedReader reader = null;
String s = null;
try {
fis = new FileInputStream(fileName);
reader = new BufferedReader(new InputStreamReader(fis, "GBK"));
while (true) {
s = reader.readLine();
if (s == null)
break;
// 由于目前尚未确定以何种方式发送，所以先打出log日志。
Log.i("info", s.toString());
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally { // 关闭流
try {
reader.close();
fis.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
三、开发过程中遇到的坑
如果在activity创建的时候崩溃的话，系统有时候（目前不确定什么情况下会重启）会重启当前的activity，造成第二次的崩溃，如此循环……
所以，在应用崩溃时要完全退出应用。
public class MyActivityLifecycleCallbacks implements ActivityLifecycleCallbacks {
private List<Activity> activities = new LinkedList<>();
public static int sAnimationId = 0;
@Override
public void onActivityCreated(Activity activity, Bundle savedInstanceState) {
addActivity(activity);
}
@Override
public void onActivityStarted(Activity activity) {
}
@Override
public void onActivityResumed(Activity activity) {
}
@Override
public void onActivityPaused(Activity activity) {
}
@Override
public void onActivityStopped(Activity activity) {
}
@Override
public void onActivitySaveInstanceState(Activity activity, Bundle outState) {
}
@Override
public void onActivityDestroyed(Activity activity) {
removeActivity(activity);
}
/**
* 添加Activity
*/
public void addActivity(Activity activity) {
if (activities == null) {
activities = new LinkedList<>();
}
if (!activities.contains(activity)) {
activities.add(activity);// 把当前Activity添加到集合中
}
}
/**
* 移除Activity
*/
public void removeActivity(Activity activity) {
if (activities.contains(activity)) {
activities.remove(activity);
}
if (activities.size() == 0) {
activities = null;
}
}
/**
* 销毁所有activity
*/
public void removeAllActivities() {
for (Activity activity : activities) {
if (null != activity) {
activity.finish();
activity.overridePendingTransition(0, sAnimationId);
}
}
}
}
