小编Lou*_*s B的帖子

我正在使用RxJava和Retofit开发一个Android应用程序.当我在API 23上测试我的代码时,我没有错误,但是当我在API 15中测试时,我的RxJava似乎无法正常工作,我的应用程序崩溃并出现错误:

FATAL EXCEPTION: main
java.lang.ExceptionInInitializerError
at $Proxy1.createToken(Native Method)
at com.loginsignup.presenter.LoginPresenterImpl.tryToLogin(LoginPresenterImpl.java:39)
at com.loginsignup.view.LoginActivity.tryToLogin(LoginActivity.java:197)
at com.loginsignup.view.LoginActivity.onClick(LoginActivity.java:180)
at android.view.View.performClick(View.java:4084)
at android.view.View$PerformClick.run(View.java:16966)
at android.os.Handler.handleCallback(Handler.java:615)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4745)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NoClassDefFoundError: rx.plugins.RxJavaPlugins
at rx.Observable.<clinit>(Observable.java:63)
at $Proxy1.createToken(Native Method) 
at com.gooroo.gooroo.loginsignup.presenter.LoginPresenterImpl.tryToLogin(LoginPresenterImpl.java:39) 
at com.gooroo.gooroo.loginsignup.view.LoginActivity.tryToLogin(LoginActivity.java:197) 
at com.gooroo.gooroo.loginsignup.view.LoginActivity.onClick(LoginActivity.java:180) 
at android.view.View.performClick(View.java:4084) 
at android.view.View$PerformClick.run(View.java:16966) 
at android.os.Handler.handleCallback(Handler.java:615) 
at android.os.Handler.dispatchMessage(Handler.java:92) 
at android.os.Looper.loop(Looper.java:137) 
at android.app.ActivityThread.main(ActivityThread.java:4745) 
at java.lang.reflect.Method.invokeNative(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:511) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553) 
at dalvik.system.NativeStart.main(Native Method)

这是我的gradle构建: …

我有一个全局变量框架,即JFrame.

public static void setUp(final Wheel []player, final phraser p) throws IOException {        
    final JPanel scorePanel=new JPanel();
    final JPanel namePanel=new JPanel();
    panel=new JPanel(new GridLayout(1,player.length,1,1));
    panel1=new JPanel();
    panel2=new JPanel();
    panel3=new JPanel(new GridLayout(2,1,1,1));

    panel3.add(new JLabel("Dead letters/phrases:"));
    panel3.add(LettersOrPhGuessed);
    JMenuBar menuBar=new JMenuBar();
    frame.setJMenuBar(menuBar);
    clock=new JMenu();
    JMenu file=new JMenu("File");       
    JMenuItem exit=new JMenuItem("Exit");
    JMenuItem reset=new JMenuItem("Reset");
    file.add(exit);
    file.add(reset);
    menuBar.add(file);
    menuBar.add(clock);

    exit.addActionListener(new ActionListener(){
        public void actionPerformed(ActionEvent e){
            System.exit(0);
        }
    });

    reset.addActionListener(new ActionListener(){//help me
        public void actionPerformed(ActionEvent e){
            frame.removeAll();
            frame.validate();
            frame.setVisible(false);
            try {
                startApp();
            } catch (IOException e1) …

首先,我是Android编程新手.我有一个非常直截了当的问题,我无法在任何地方找到答案.

假设我有2 Activity秒呼叫A,B并且两者都开始了,如何在Activity不声明s的新实例Activity且没有按下后退按钮的情况下切换s .在两个Activitys中我都有另一个的全局引用.我使用这种setVisible()方法吗？这些文件似乎没有让我清楚这一点.

提前致谢.