Question

我在Android演示中创建了4个活动。当我的问题从我的第一个活动运行应用程序以显示第二个活动我正试图让数据保持原样按下应用程序退出的3活动中的后退按钮但是当我回到第三个活动和数据时，我重新启动保持原样相同。我使用Intent使用共享首选项但它运作不正常

@Override
    public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.splash_screen);



        final SharedPreferences sharedPref=this.getSharedPreferences("MY_PREF_1",MODE_WORLD_READABLE);
        SharedPreferences.Editor shredPref_Editor=sharedPref.edit();
        //shredPref_Editor.putString(MY_ACTIVITY,"splash_activity");
        prefName = sharedPref.getString(MY_ACTIVITY,"splash_activity");

        handler = new Handler(){};

        runnable = new Runnable() {

            @Override
            public void run() {
                // TODO Auto-generated method stub

                if(prefName == "splash_activity" || prefName.toString().trim().equals("Number_Activity"))
                {
                    Intent i1=new Intent(Splash_Screen_Activity.this,Number_Activity.class);
                    startActivity(i1);
                }


                else if(prefName.toString().trim().equals("pin_number_activity"))
                {
                    Intent i2=new Intent(Splash_Screen_Activity.this,PIN_Number_Activity.class);
                    startActivity(i2);
                }


                else
                {
                    Intent i3=new Intent(Splash_Screen_Activity.this , Custom_Title_Bar_Activity.class);
                    startActivity(i3);
                }

            }
        };






 public class Number_Activity extends Activity
    {
        private final String MY_ACTIVITY = "Number_Activity";

    public void onCreate(Bundle savedInstanceState)
        {

            super.onCreate(savedInstanceState);
            setContentView(R.layout.cell_number);

            SharedPreferences sharedPref=this.getSharedPreferences("MY_PREF_2",MODE_WORLD_READABLE);
            SharedPreferences.Editor shredPref_Editor=sharedPref.edit();
            shredPref_Editor.putString(MY_ACTIVITY,"number_activity");
            shredPref_Editor.commit();
        }   
    }




public class PIN_Number_Activity extends Activity
{
    private final String MY_ACTIVITY = "PinNum_MyActivity";


         public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.pin_number);

        SharedPreferences sharedPref=this.getSharedPreferences("MY_PREF_3",MODE_WORLD_READABLE);
        SharedPreferences.Editor shredPref_Editor=sharedPref.edit();
        shredPref_Editor.putString(MY_ACTIVITY,"pin_number_activity");
        shredPref_Editor.commit();
        }
}





public class Custom_Title_Bar_Activity extends Activity
{
    private final String MY_ACTIVITY = "Main_Activity";


protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        Boolean customTitleSupported=requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);
        setContentView(R.layout.main_for_ctitlebar);

        SharedPreferences sharedPref=this.getSharedPreferences("MY_PREF_4",MODE_WORLD_READABLE);
        SharedPreferences.Editor shredPref_Editor=sharedPref.edit();
        shredPref_Editor.putString(MY_ACTIVITY,"main_activity");
        shredPref_Editor.commit();

}

}

如何显示最近的活动？

0 个答案: