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安卓认为我不会关闭我的数据库!为什么?

  •  3
  • hermy  · 技术社区  · 16 年前

    我有一个sqliteDatabase数据成员,我在onCreate中初始化,并在onPause()、onStop()和onDestroy()中调用.close()。它在onresume()中重新初始化。它似乎运行得很好,但当我查看调试器时,它看到了:

    08-24 20:23:50.014: ERROR/Database(6767): Leak found
    08-24 20:23:50.014: ERROR/Database(6767): java.lang.IllegalStateException: /data/data/com.hh.Timepunch/databases/times_database.db SQLiteDatabase created and never closed
    08-24 20:23:50.014: ERROR/Database(6767):     at android.database.sqlite.SQLiteDatabase.<init>(SQLiteDatabase.java:1695)
    08-24 20:23:50.014: ERROR/Database(6767):     at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:739)
    08-24 20:23:50.014: ERROR/Database(6767):     at android.database.sqlite.SQLiteDatabase.openOrCreateDatabase(SQLiteDatabase.java:761)
    08-24 20:23:50.014: ERROR/Database(6767):     at android.database.sqlite.SQLiteDatabase.openOrCreateDatabase(SQLiteDatabase.java:754)
    08-24 20:23:50.014: ERROR/Database(6767):     at android.app.ApplicationContext.openOrCreateDatabase(ApplicationContext.java:476)
    08-24 20:23:50.014: ERROR/Database(6767):     at android.content.ContextWrapper.openOrCreateDatabase(ContextWrapper.java:193)
    08-24 20:23:50.014: ERROR/Database(6767):     at com.hh.Timepunch.TimeSheetActivity.onCreate(TimeSheetActivity.java:72)
    08-24 20:23:50.014: ERROR/Database(6767):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
    08-24 20:23:50.014: ERROR/Database(6767):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2459)
    08-24 20:23:50.014: ERROR/Database(6767):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2512)
    08-24 20:23:50.014: ERROR/Database(6767):     at android.app.ActivityThread.access$2200(ActivityThread.java:119)
    08-24 20:23:50.014: ERROR/Database(6767):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1863)
    08-24 20:23:50.014: ERROR/Database(6767):     at android.os.Handler.dispatchMessage(Handler.java:99)
    08-24 20:23:50.014: ERROR/Database(6767):     at android.os.Looper.loop(Looper.java:123)
    08-24 20:23:50.014: ERROR/Database(6767):     at android.app.ActivityThread.main(ActivityThread.java:4363)
    08-24 20:23:50.014: ERROR/Database(6767):     at java.lang.reflect.Method.invokeNative(Native Method)
    08-24 20:23:50.014: ERROR/Database(6767):     at java.lang.reflect.Method.invoke(Method.java:521)
    08-24 20:23:50.014: ERROR/Database(6767):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
    08-24 20:23:50.014: ERROR/Database(6767):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
    08-24 20:23:50.014: ERROR/Database(6767):     at dalvik.system.NativeStart.main(Native Method)
    08-24 20:23:50.054: ERROR/Database(6767): Leak found
    08-24 20:23:50.054: ERROR/Database(6767): java.lang.IllegalStateException: /data/data/com.hh.Timepunch/databases/times_database.db SQLiteDatabase created and never closed
    08-24 20:23:50.054: ERROR/Database(6767):     at android.database.sqlite.SQLiteDatabase.<init>(SQLiteDatabase.java:1695)
    08-24 20:23:50.054: ERROR/Database(6767):     at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:739)
    08-24 20:23:50.054: ERROR/Database(6767):     at android.database.sqlite.SQLiteDatabase.openOrCreateDatabase(SQLiteDatabase.java:761)
    08-24 20:23:50.054: ERROR/Database(6767):     at android.database.sqlite.SQLiteDatabase.openOrCreateDatabase(SQLiteDatabase.java:754)
    08-24 20:23:50.054: ERROR/Database(6767):     at android.app.ApplicationContext.openOrCreateDatabase(ApplicationContext.java:476)
    08-24 20:23:50.054: ERROR/Database(6767):     at android.content.ContextWrapper.openOrCreateDatabase(ContextWrapper.java:193)
    08-24 20:23:50.054: ERROR/Database(6767):     at com.hh.Timepunch.TimepunchActivity.onCreate(TimepunchActivity.java:60)
    08-24 20:23:50.054: ERROR/Database(6767):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
    08-24 20:23:50.054: ERROR/Database(6767):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2459)
    08-24 20:23:50.054: ERROR/Database(6767):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2512)
    08-24 20:23:50.054: ERROR/Database(6767):     at android.app.ActivityThread.access$2200(ActivityThread.java:119)
    08-24 20:23:50.054: ERROR/Database(6767):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1863)
    08-24 20:23:50.054: ERROR/Database(6767):     at android.os.Handler.dispatchMessage(Handler.java:99)
    08-24 20:23:50.054: ERROR/Database(6767):     at android.os.Looper.loop(Looper.java:123)
    08-24 20:23:50.054: ERROR/Database(6767):     at android.app.ActivityThread.main(ActivityThread.java:4363)
    08-24 20:23:50.054: ERROR/Database(6767):     at java.lang.reflect.Method.invokeNative(Native Method)
    08-24 20:23:50.054: ERROR/Database(6767):     at java.lang.reflect.Method.invoke(Method.java:521)
    08-24 20:23:50.054: ERROR/Database(6767):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
    08-24 20:23:50.054: ERROR/Database(6767):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
    08-24 20:23:50.054: ERROR/Database(6767):     at dalvik.system.NativeStart.main(Native Method)
    08-24 20:23:50.199: ERROR/libs3c2drender(1912): int S3c2DRender::DoG2D(unsigned int, s3c_img*, s3c_rect*, unsigned int, s3c_img*, s3c_rect*, int, int)::S3C_G2D_ROTATOR_18176 fail
    

    我得到此错误的地方之一是离开此活动时:

    public class TimepunchActivity extends Activity {
    
            Calendar timeNow = Calendar.getInstance();
            SQLiteDatabase timesDatabase;
    
            @Override
            public void onCreate(Bundle savedInstanceState) {
                super.onCreate(savedInstanceState);
                setContentView(R.layout.timepunch);
    
                //Create/open and configure database (if necessary)
                timesDatabase = openOrCreateDatabase(
                        "times_database.db",
                        SQLiteDatabase.CREATE_IF_NECESSARY,
                        null);
                timesDatabase.setLocale(Locale.getDefault());
                timesDatabase.setLockingEnabled(false);
                timesDatabase.setVersion(3);
    
                //lenient is set to true so incrementing minute 59 auto increments hour, etc
                timeNow.setLenient(true);
    
                //Create table (if necessary)
                final String dbCommand = "CREATE TABLE IF NOT EXISTS Timepunches (punch INTEGER PRIMARY KEY);";
                timesDatabase.execSQL(dbCommand);
    
                updateLastInPunch();
    
                Button punchButton = (Button)findViewById(R.id.punch_button);
                punchButton.setHapticFeedbackEnabled(true);
                punchButton.setOnClickListener(new View.OnClickListener() {
                    public void onClick(View v) {
                        //Insert data
                        ContentValues punchValue = new ContentValues();
                        punchValue.put("punch", timeNow.getTimeInMillis());
                        long newPunchID = timesDatabase.insert("Timepunches", null, punchValue);
                        punchValue.clear();
    
                        //if punch already exists
                        if (newPunchID < 0) {
                            AlertDialog.Builder builder = new AlertDialog.Builder(TimepunchActivity.this);
                            builder.setTitle("Whoops")
                                .setMessage("I've already recorded a punch for this time and day.")
                                .setCancelable(true)
                                .setNeutralButton("Oh", new DialogInterface.OnClickListener() {
                                    public void onClick(DialogInterface dialog, int id) {
                                        dialog.cancel();
                                    }
                                })
                                .show();
                        }
                        else {
                        }
                    } //end setOnClick()
                }); //end click listener for punchButton
            } //end onCreate()
    
    
    
            @Override
            public void onResume() {
                super.onResume();
                checkFirstTimer();
    
                //Open and configure database
                timesDatabase = openOrCreateDatabase(
                        "times_database.db",
                        SQLiteDatabase.CREATE_IF_NECESSARY,
                        null);
                timesDatabase.setLocale(Locale.getDefault());
                timesDatabase.setLockingEnabled(false);
                timesDatabase.setVersion(3);
    
    
                //Update date object for current time
                timeNow.setTimeInMillis(System.currentTimeMillis());
                timeNow.set(Calendar.SECOND, 0);
                timeNow.set(Calendar.MILLISECOND, 0);
                updateClock((TextView)findViewById(R.id.current_time_textbox), timeNow);
    
                updateLastInPunch();
            } //end onResume()
    
    
            @Override
            public void onPause() {
                super.onPause();
                timesDatabase.close();
            } //end onResume()
    
            @Override
            public void onStop() {
                super.onStop();
                timesDatabase.close();
            } //end onResume()
    
            @Override
            public void onDestroy() {
                super.onDestroy();
                timesDatabase.close();
            } //end onResume()
    
    
    
            //Shows last in-punch that has no out-punch
            // if there is none it hides the section
            public void updateLastInPunch() {
                Cursor punchCursor = timesDatabase.query("Timepunches", null, null, null, null, null, "punch ASC;");
    
                TextView inPunchLabel = (TextView)findViewById(R.id.in_punch_label_textview);
                TextView inPunchTV = (TextView)findViewById(R.id.in_punch_time_textview);
    
                //odd count means there is a missing punch (assumed to be latest in punch)
                // therefore show last in punch
                if ((punchCursor.getCount()%2) != 0) {
                    punchCursor.moveToLast();
                    Calendar lastIn = Calendar.getInstance();
                    lastIn.setTimeInMillis(punchCursor.getLong(0));
    
                    updateClock((TextView)findViewById(R.id.in_punch_time_textview), lastIn);
    
                    inPunchLabel.setVisibility(View.VISIBLE);
                    inPunchLabel.setAnimation(fadeInAnimation);
                    inPunchLabel.startAnimation(fadeInAnimation);
    
                    inPunchTV.setVisibility(View.VISIBLE);
                    inPunchTV.setAnimation(fadeInAnimation);
                    inPunchTV.startAnimation(fadeInAnimation);
                }
                else {
                    //only fade when "turning off" last punch display
                    // (don't fade away when returning to screen)
                    if (inPunchLabel.getVisibility() == View.VISIBLE) {
                        inPunchLabel.setAnimation(fadeOutAnimation);
                        inPunchLabel.startAnimation(fadeOutAnimation);
                        inPunchLabel.setVisibility(View.INVISIBLE);
    
                        inPunchTV.setAnimation(fadeOutAnimation);
                        inPunchTV.startAnimation(fadeOutAnimation);
                        inPunchTV.setVisibility(View.INVISIBLE);
                    }
                }
                punchCursor.close();
            } //end getLastInPunch()
        } //end TimepunchActivity
    

    但奇怪的是,这个错误并不是持久的。

    在call.close()之后,我还需要做更多的工作吗?

    2 回复  |  直到 16 年前
        1
  •  4
  •   EboMike    16 年前

    问题是,你在创建/打开它,然后在继续,所以你做了两次。同样,你要关闭它两次,所以它可能会崩溃。

    一般来说-你为什么不使用 SQLiteOpenHelper ?这将使管理数据库更加容易。

        2
  •  2
  •   cdonner    16 年前

    为了支持电子书的观点,请看 Android Activity lifecycle 您的代码的问题将是显而易见的。