当我按下后退按钮时将数据传输到 "Choose activity"

Question

现在我运行新 Intent 并通过 "MainActivity" 中的按钮将数据传输到 "PlayTravelledRouteActivity"，如下图所示：

但我想要运行来自 "Choose Activity" 的新 Intent，所以我认为我应该事先将数据传输到 "Choose Activity" 和 "PlayTravelledRouteActivity" 旁边，但要到达 "Choose Activity" 来自 "MainActivity" 我需要点击（智能手机）后退按钮，如下图所示：

而且我知道在哪里插入代码以将数据从 "Choose Activity" 传输到 "PlayTravelledRouteActivity"（在按钮 "Play" onClickListener 中），但是 我不知道在哪里我应该插入此代码：

/** lat_GPS,lon_GPS,roll_angle,pitch_angle -> double[] = new double[600], licznik -> int **/
Intent intent1 = new Intent(this, ChooseActivity.class);
intent1.putExtra("lat",lat_GPS);
intent1.putExtra("lon",lon_GPS);
intent1.putExtra("last_index",licznik);
intent1.putExtra("roll_angle",roll_Kalman_Filter);
intent1.putExtra("pitch_angle",pitch_Kalman_Filter);
startActivity(intent1);

将数据从 "MainActivity" 传输到 "Choose Activity"？有人可以告诉我吗？

Answer 1

根据你的问题可以使用onBackPressed()

Called when the activity has detected the user's press of the back key. The default implementation simply finishes the current activity, but you can override this to do whatever you want.

@Override
   public void onBackPressed() 
    {
        //super.onBackPressed();
        Intent intent1 = new Intent(this, ChooseActivity.class);
        intent1.putExtra("lat",lat_GPS);
        intent1.putExtra("lon",lon_GPS);
        intent1.putExtra("last_index",licznik);
        intent1.putExtra("roll_angle",roll_Kalman_Filter);
        intent1.putExtra("pitch_angle",pitch_Kalman_Filter);
        startActivity(intent1);
    }

当我按下后退按钮时将数据传输到 "Choose activity"

Transfer data to "Choose activity" when I press back button

android

transition

transfer