In the development of Android, sometimes due to some exceptions caused by the application error, occasionally crash due to errors, resulting in a drop in user experience, in order to solve this problem, we have to deal with such an exception: The code is as follows: Crashhandler.java
Import Android.content.context;import android.content.Intent; Import Android.content.pm.packageinfo;import Android.content.pm.packagemanager;import Android.content.pm.packagemanager.namenotfoundexception;import Android.os.build;import android.os.Environment; Import Android.os.looper;import Android.util.log;import android.widget.Toast;
Import com......activity. Splashactivity;import Com.......util. Imgcliputil;
Import Java.io.file;import java.io.fileoutputstream;import Java.io.printwriter;import Java.io.StringWriter;import Java.io.writer;import Java.lang.thread.uncaughtexceptionhandler;import Java.lang.reflect.field;import Java.text.dateformat;import Java.text.simpledateformat;import Java.util.date;import Java.util.HashMap;import Java.util.Map;
/** * Uncaughtexception processing class, when the program occurs uncaught exception, there is the class to take over the program, and record send error report. * * @author User * */public class Crashhandler implements Uncaughtexceptionhandler {
public static final String TAG = "Crashhandler";
Crashhandler instance private static Crashhandler INSTANCE = new Crashhandler ();
The context object of the program is private context Mcontext;
The system default Uncaughtexception processing class private Thread.uncaughtexceptionhandler mdefaulthandler;
Used to store device information and exception information private map<string, string> infos = new hashmap<string, string> ();
Used to format the date as part of the log file name private DateFormat formatter = new SimpleDateFormat ("Yyyy-mm-dd-hh-mm-ss");
/** guarantees that there is only one Crashhandler instance */Private Crashhandler () {}
/** get Crashhandler instance, Singleton mode */public static Crashhandler getinstance () {return INSTANCE; }
/** * Initialize * * @param context */public void init (context context) {Mcontext = context;
Gets the system default Uncaughtexception processor Mdefaulthandler = Thread.getdefaultuncaughtexceptionhandler ();
Set the Crashhandler as the program's default processor Thread.setdefaultuncaughtexceptionhandler (this); }
/** * When uncaughtexception occurs, it is transferred to the function to process */@Override public void uncaughtexception (thread thread, Throwable E x) {//delete crop left in cached photo Imgcliputil.deleteallfiles (Imgcliputil.imgclippath); if (!handleexception (ex) && Mdefaulthandler! = null) {//If the user does not handle it, let the system default exception handler handle the Mdefaultha Ndler.uncaughtexception (thread, ex); } else {try {thread.sleep (2000); } catch (Interruptedexception e) {log.e (TAG, "error:", e); }
Exit the program, note the following Reboot Launcher Code///Android.os.Process.killProcess (Android.os.Process.myPid ());//System.exit (1) ; Restart the program, commenting the exit program above Intent Intent = new Intent (); Intent.setclass (Mcontext, Splashactivity.class); Intent.addflags (Intent.flag_activity_new_task); Mcontext.startactivity (Intent); Android.os.Process.killProcess (Android.os.Process.myPid ()); } }
/** * Custom error handling, collecting error messages, sending error reports and so on are done here * * @param ex * @return true: If the exception information is processed; otherwise false */private B Oolean HandleException (Throwable ex) {if (ex = = null) {return false; }
Use Toast to display exception information new Thread () {@Override public void run () {Looper.prepar E (); Toast.maketext (Mcontext, "Sorry, the program has an exception and is about to exit.) ", Toast.length_long). Show (); Looper.loop (); }}.start ();
Collect equipment parameter information collectdeviceinfo (MCONTEXT); Save log file Savecrashinfo2file (ex); return true; }
/** * Collect device parameter information * @param CTX */public void Collectdeviceinfo (Context ctx) {try {Package Manager 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 if 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); } } }
/** * Save error message to file * * @param ex * @return return file name for easy Transfer of file to server */private String Savecrashinfo2file (T Hrowable 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 ()); String fileName = "crash-" + Time + "-" + timestamp + ". Log";
if (Environment.getexternalstoragestate (). Equals (environment.media_mounted)) {String Path = "/sdcard/tpage s/crash/"; File dir = new file (path); if (!dir.exists ()) {dir.mkdirs (); FileOutputStream fos = new FileOutputStream (path + fileName); Fos.write (Sb.tostring (). GetBytes ()); Fos.close (); }
return fileName; } catch (Exception e) {log.e (TAG, "An error occured while writing file ...", e); }
return null; }}
myapplication.java/** * Created by IT01 on 2015/10/28 0028. */public class MyApplication extends application {/* private refwatcher mrefwatcher;
public static Refwatcher Getrefwatcher (context context) {MyApplication application = (MyApplication) Context.getap Plicationcontext (); return application.mrefwatcher; }*/
@Override public void OnCreate () {super.oncreate ();//Mrefwatcher = Leakcanary.install (this); The cookie policy allows Okhttp to accept all cookie/* cookiemanager Cookiemanager = new Cookiemanager (); Okhttp.setcookie (Cookiemanager); * *
if (Constants.Config.DEVELOPER_MODE && Build.VERSION.SDK_INT >= build.version_codes. Gingerbread) {Strictmode.setthreadpolicy (New StrictMode.ThreadPolicy.Builder (). Detectall (). Penaltydialog (). Bui LD ()); Strictmode.setvmpolicy (New StrictMode.VmPolicy.Builder (). Detectall (). Penaltydeath (). build ()); } if (Android.os.Build.VERSION.SDK_INT > 9) {strictmode.threadpolicy policy = new STRICTMODE.THREADP Olicy. Builder (). Permitall (). build (); Strictmode.setthreadpolicy (Policy); }
Crashhandler Crashhandler = Crashhandler.getinstance ();//Crashhandler.init (Getapplicationcontext ());
}
}
Imgcliputil.javaimport Android.graphics.bitmap;import Android.graphics.Matrix;
Import Java.io.bufferedoutputstream;import java.io.file;import Java.io.fileoutputstream;import java.io.IOException ;
/** * Created by IT01 on 2015/12/14 0014. */public class Imgcliputil {public static Boolean isclip (Bitmap bit) {int w = bit.getwidth ();//Get picture width, height int h = bit.getheight (); if ((w==h) &&w<1080) return false; return true; The public static int getsquaresize (Bitmap bit) {int w = bit.getwidth ();//Gets the width of the picture, high int h = bit.getheight ( ); int WH = w > h? h:w;//the square area to be taken after trimming return WH > 1080? 1080:WH; }
public static Bitmap Scalebitmap (Bitmap Bitmap, int edgelength) {
if (null = = Bitmap | | edgelength <= 0) {return null; }
Bitmap result = Bitmap; int widthorg = Bitmap.getwidth (); int heightorg = Bitmap.getheight ();
if (widthorg >= edgelength && heightorg >= edgelength) { //compress to a minimum length of edgelength bitmap INT lon Geredge = (int) (Edgelength * Math.max (widthorg, heightorg)/Math.min (widthorg, heightorg)); &N Bsp int scaledwidth = widthorg > heightorg? longeredge:edgelength; int scaledheight = widthorg > heightorg? edgelength:longeredge; Bitmap scaledbitmap; & nbsp try{ Scaledbitmap = Bitmap.createscaledbitmap (Bitmap, Scaledwidth, Scaledheight, True); } catch (Exception e) { return null; &NBSP }
Intercept the square part in the middle. int xtopleft = (scaledwidth-edgelength)/2; int ytopleft = (scaledheight-edgelength)/2;
try{result = Bitmap.createbitmap (Scaledbitmap, Xtopleft, Ytopleft, Edgelength, edgelength); Scaledbitmap.recycle (); } catch (Exception e) {return null; } }
return result; }
/** * Save File * @param BM * @param fileName * @throws IOException */public static void SaveFile (Bitma P BM, String fileName) throws IOException {string path =imgclippath+ "/";//"/sdcard/revoeye/"; File Dirfile = new file (path); if (!dirfile.exists ()) {Dirfile.mkdir (); } File Mycapturefile = new file (path + fileName); Bufferedoutputstream BOS = new Bufferedoutputstream (new FileOutputStream (Mycapturefile)); Bm.compress (Bitmap.CompressFormat.JPEG, N, BOS); Bos.flush (); Bos.close (); }
//rotate pictures /** * rotate pictures by an angle * * @param bm * need to rotate the picture * @param degree * Rotate angle * @return rotated picture */ &nbs P Public Bitmap Rotatebitmapbydegree (Bitmap BM, int degree) { Bitmap RETURNBM = null;   ; //rotation matrix generation based on rotation angle Matrix matrix = new Matrix ()// matri X.postrotate (degree); matrix.setrotate (degree, (float) bm.getwidth ()/2, (float) Bm.getheight ()/2); Try { //rotate the original image according to the rotation matrix and get a new picture and nbsp RETURNBM = bitmap.createbitmap (BM, 0, 0, bm.getwidth (), Bm.getheight (), Matrix, True); & nbsp } catch (OutOfMemoryError e) { e.printstacktrace (); } if (RETURNBM = = null) { RETURNBM = bm; & nbsp } if (BM! = RETURNBM) { bm.recycle (); &NB Sp } return returnbm; }
public static file Imgclippath =new file (Utils.getpicpath () + "img"); public static void Deleteallfiles (File root) {
File files[] = root.listfiles (); if (Files! = null) &N Bsp for (File f:files) { if (f.isdirectory ()) { Determine if folder deleteallfiles (f); &N Bsp Try { &NBSP ; F.delete (); } catch (Exception e) { &nbs P } } else {& nbsp if (f.exists ()) {//Determine existence &NBS P deleteallfiles (f); Try { &NBS P F.delete (); } catch (Exception E ) { } } } } }
}
From for notes (Wiz)
An Android app crashes after an exception is captured and restarted and written to the log
