我想在当前日期添加90天,这是我的代码。我在网上尝试了一些例子,但它似乎没有用。
SimpleDateFormat dateFormat = new SimpleDateFormat("dd-MM-yyyy");
Calendar date = Calendar.getInstance();
couponcreated = dateFormat.format(date);
date.add(Calendar.DATE,90);
SimpleDateFormat dateFormat1 = new SimpleDateFormat("dd-MM-yyyy");
couponexpires = dateFormat1.format(date.getTime());
couponexpiredate.setText(couponexpires);
但是,我收到错误,导致我的应用程序崩溃。
java.lang.RuntimeException: Unable to start activity ComponentInfo{info.androidhive.loginandregistration/info.androidhive.loginandregistration.CouponReceivePageActivity}: java.lang.IllegalArgumentException: Bad class: class java.util.GregorianCalendar
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2295)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2349)
at android.app.ActivityThread.access$700(ActivityThread.java:159)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1316)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5419)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1209)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1025)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.IllegalArgumentException: Bad class: class java.util.GregorianCalendar
at java.text.DateFormat.format(DateFormat.java:296)
at java.text.Format.format(Format.java:93)
at info.androidhive.loginandregistration.CouponReceivePageActivity.onCreate(CouponReceivePageActivity.java:55)
at android.app.Activity.performCreate(Activity.java:5372)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1104)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2257)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2349)
at android.app.ActivityThread.access$700(ActivityThread.java:159)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1316)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5419)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
这是我的logcat代码。
答案 0 :(得分:1)
您的错误是您第一次尝试格式化日期时 你应该写:
couponcreated = dateFormat.format(date.getTime());
而不是
couponcreated = dateFormat.format(date);
因为日历无法直接格式化,您需要使用getTime()
函数从日历中获取日期