Question

当我尝试运行我的应用程序以查看它是否有效时，它崩溃并且只是说它停止工作。我的应用程序旨在检查当前日期和时间，然后检查计划（数组），然后将文本字段更改为下一次渡轮的时间。据我检查，代码将做我想做的事情（我不确定）。无论如何这是会话日志：

05-02 21:09:20.350: D/AndroidRuntime(935): Shutting down VM
05-02 21:09:20.350: W/dalvikvm(935): threadid=1: thread exiting with uncaught exception (group=0xb4a85ba8)
05-02 21:09:20.370: E/AndroidRuntime(935): FATAL EXCEPTION: main
05-02 21:09:20.370: E/AndroidRuntime(935): Process: sep.justin.statenislandferry, PID: 935
05-02 21:09:20.370: E/AndroidRuntime(935): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{sep.justin.statenislandferry/com.example.statenislandferry.MainActivity}: java.lang.NullPointerException
05-02 21:09:20.370: E/AndroidRuntime(935):      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2121)
05-02 21:09:20.370: E/AndroidRuntime(935):      at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
05-02 21:09:20.370: E/AndroidRuntime(935):      at android.app.ActivityThread.access$800(ActivityThread.java:135)
05-02 21:09:20.370: E/AndroidRuntime(935):      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
05-02 21:09:20.370: E/AndroidRuntime(935):      at android.os.Handler.dispatchMessage(Handler.java:102)
05-02 21:09:20.370: E/AndroidRuntime(935):      at android.os.Looper.loop(Looper.java:136)
05-02 21:09:20.370: E/AndroidRuntime(935):      at android.app.ActivityThread.main(ActivityThread.java:5017)
05-02 21:09:20.370: E/AndroidRuntime(935):      at java.lang.reflect.Method.invokeNative(Native Method)
05-02 21:09:20.370: E/AndroidRuntime(935):      at java.lang.reflect.Method.invoke(Method.java:515)
05-02 21:09:20.370: E/AndroidRuntime(935):      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
05-02 21:09:20.370: E/AndroidRuntime(935):      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
05-02 21:09:20.370: E/AndroidRuntime(935):      at dalvik.system.NativeStart.main(Native Method)
05-02 21:09:20.370: E/AndroidRuntime(935): Caused by: java.lang.NullPointerException
05-02 21:09:20.370: E/AndroidRuntime(935):      at android.app.Activity.findViewById(Activity.java:1884)
05-02 21:09:20.370: E/AndroidRuntime(935):      at com.example.statenislandferry.MainActivity.<init>(MainActivity.java:22)
05-02 21:09:20.370: E/AndroidRuntime(935):      at java.lang.Class.newInstanceImpl(Native Method)
05-02 21:09:20.370: E/AndroidRuntime(935):      at java.lang.Class.newInstance(Class.java:1208)
05-02 21:09:20.370: E/AndroidRuntime(935):      at android.app.Instrumentation.newActivity(Instrumentation.java:1061)
05-02 21:09:20.370: E/AndroidRuntime(935):      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2112)
05-02 21:09:20.370: E/AndroidRuntime(935):      ... 11 more

更新：

05-02 22:05:02.090: W/ResourceType(824): No package identifier when getting value for resource number 0x00000406
05-02 22:05:02.090: D/AndroidRuntime(824): Shutting down VM
05-02 22:05:02.100: W/dalvikvm(824): threadid=1: thread exiting with uncaught exception (group=0xb4a2dba8)
05-02 22:05:02.110: E/AndroidRuntime(824): FATAL EXCEPTION: main
05-02 22:05:02.110: E/AndroidRuntime(824): Process: sep.justin.statenislandferry, PID: 824
05-02 22:05:02.110: E/AndroidRuntime(824): java.lang.RuntimeException: Unable to start activity ComponentInfo{sep.justin.statenislandferry/com.example.statenislandferry.MainActivity}: android.content.res.Resources$NotFoundException: String resource ID #0x406
05-02 22:05:02.110: E/AndroidRuntime(824):      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
05-02 22:05:02.110: E/AndroidRuntime(824):      at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
05-02 22:05:02.110: E/AndroidRuntime(824):      at android.app.ActivityThread.access$800(ActivityThread.java:135)
05-02 22:05:02.110: E/AndroidRuntime(824):      at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
05-02 22:05:02.110: E/AndroidRuntime(824):      at android.os.Handler.dispatchMessage(Handler.java:102)
05-02 22:05:02.110: E/AndroidRuntime(824):      at android.os.Looper.loop(Looper.java:136)
05-02 22:05:02.110: E/AndroidRuntime(824):      at android.app.ActivityThread.main(ActivityThread.java:5017)
05-02 22:05:02.110: E/AndroidRuntime(824):      at java.lang.reflect.Method.invokeNative(Native Method)
05-02 22:05:02.110: E/AndroidRuntime(824):      at java.lang.reflect.Method.invoke(Method.java:515)
05-02 22:05:02.110: E/AndroidRuntime(824):      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
05-02 22:05:02.110: E/AndroidRuntime(824):      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
05-02 22:05:02.110: E/AndroidRuntime(824):      at dalvik.system.NativeStart.main(Native Method)
05-02 22:05:02.110: E/AndroidRuntime(824): Caused by: android.content.res.Resources$NotFoundException: String resource ID #0x406
05-02 22:05:02.110: E/AndroidRuntime(824):      at android.content.res.Resources.getText(Resources.java:244)
05-02 22:05:02.110: E/AndroidRuntime(824):      at android.widget.TextView.setText(TextView.java:3888)
05-02 22:05:02.110: E/AndroidRuntime(824):      at com.example.statenislandferry.MainActivity.onCreate(MainActivity.java:18)
05-02 22:05:02.110: E/AndroidRuntime(824):      at android.app.Activity.performCreate(Activity.java:5231)
05-02 22:05:02.110: E/AndroidRuntime(824):      at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
05-02 22:05:02.110: E/AndroidRuntime(824):      at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)
05-02 22:05:02.110: E/AndroidRuntime(824):      ... 11 more
05-02 22:05:06.750: I/Process(824): Sending signal. PID: 824 SIG: 9

这是代码：

public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    TextView ferryTime = (TextView)findViewById(R.id.ferrytime);
    ferryTime.setText(convert());
}
static int[] satTimes = new int[] {10,50};
static int[] sunTimes = new int[] {10,50};
static int[] weekTimes = new int[] {0,30,100,200,300,400,500,530,600,620,640,700,715,730,745,800,815,830,845,900,930,1000,1030,1100,1130,1200,1230,1300,1330,1400,1430,1500,1530,1550,1610,1630,1650,1710,1730,1745,1800,1815,1830,1845,1900,1930,2000,2030,2100,2130,2200,2230,2300,2330};

static Calendar rightNow = Calendar.getInstance();

public static String checkdate(){

    if(rightNow.get(Calendar.DAY_OF_WEEK) == Calendar.SATURDAY){
        return "saturday";
    }else if (rightNow.get(Calendar.DAY_OF_WEEK) == Calendar.SUNDAY){
        return "sunday";
    } else {
        return "weekday";
    }
}

public static int getTime(){
    int time = rightNow.get(Calendar.HOUR_OF_DAY) * 100;
    time = time + rightNow.get(Calendar.MINUTE);
    return time;
}

public static int checkTime(){
    String today = checkdate();

    if (today == "saturday"){
        for(int i = 1; i <= satTimes.length; i ++ ){
            if(satTimes[i] > getTime()){
                return satTimes[i];
            }
        }
    } else if (today == "sunday"){
        for(int i = 1; i <= sunTimes.length; i ++ ){
            if(sunTimes[i] > getTime()){
                return sunTimes[i];
            }
        }           
    } else if (today == "weekday") {
        for(int i = 1; i <= weekTimes.length; i ++ ){
            if(weekTimes[i] > getTime()){
                return weekTimes[i];
            }

        }           
    }
    return 0;
}

public static int timeLeft(){
    int actualTime = getTime();
    int ferryTime = checkTime();
    return actualTime - ferryTime;
}

public static int convert(){
    int ferrytime = checkTime();
    if (ferrytime > 1200){
        return ferrytime - 1200;
    }else{
        return ferrytime;
    }
}
}

编辑：我在修正初始化log的展示位置后更新了TextView ferrytime。

Answer 1

您正在TextView ferryTime方法之外初始化onCreate。当您致电ferryTime.setText()时，您会获得NullPointerException。将其移至onCreate，如下所示：

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    TextView ferryTime = (TextView)findViewById(R.id.ferrytime);
    ferryTime.setText(convert());
}

Android应用已意外停止

1 个答案: