我的应用程序中有正常的活动流程。如果有应用程序崩溃/用户强制关闭应用程序的实例，我确保应用程序转到用户最后一次的上一个活动。我在首选项文件中记录，当我的活动第一次启动时，我确保用户没有登录，如果他是，我会进入文件，看看他的最后位置并直接进入那里。
问题是它似乎无法工作我尝试了以下变化
Intent i = new Intent(MainActivity.this, com.example.ramapriyasridharan.trialapp04.MainQuestionsActivity.class);
startActivity(i);
Intent i = new Intent(this, MainQuestionsActivity.class);
startActivity(i);
以下是完整代码：
boolean meow = instance_user.mKinveyClient.user().isUserLoggedIn();
Log.i("main activity", "meow = " + meow);
// if already logged
if(meow){
Log.i(TAG, "(not first time): " + instance_user.mKinveyClient.user().getId());
user_text.setText("user id is " + instance_user.mKinveyClient.user().getId());
int a = s_logged.getInt("activity", 2);
Log.d(TAG, "activity going to :" + a);
Intent i = new Intent(MainActivity.this, com.example.ramapriyasridharan.trialapp04.MainQuestionsActivity.class);
i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_MULTIPLE_TASK);
// switch(a){
// case 1: i = new Intent(this, MainActivity.class);break;
// case 2: i = new Intent(this, ProfilingFeaturesActivity.class);break;
// case 4: i = new Intent(this, ProfilingSensorsActivity.class);break;
// case 5: i = new Intent(this, ProfilingDataCollectorsActivity.class);break;
// case 6: i = new Intent(this, ProfilingContextsActivity.class);break;
// case 7: i = new Intent(this, QuestionsActivity.class);break;
// case 8: i = new Intent(this, PauseActivity.class);break;
// case 9: i = new Intent(this, MainQuestionsActivity.class);break;
// }
startActivity(i);
}
这是我使用正常流程进行下一个活动的方式：
Intent intent = new Intent(this, GetUserInformation.class);
e.putInt("activity", 2);
e.commit();
intent.putExtra("user_id",user_string);
startActivity(intent);
第一个被忽略，第二个被调用，if条件很好，日志语句证明活动状态（即用户所在的位置）被正确记录。唯一的问题是意图不是叫，我不知道为什么。
欢迎任何帮助。感谢
额外代码：MainActivity.java
public class MainActivity extends AppCompatActivity {
StoreDbHelper db = null;
private static String TAG = MainActivity.class.getName();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
DatabaseInstance d = new DatabaseInstance(this);
db = DatabaseInstance.db;
// do not let screen switch off
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
final SharedPreferences s_logged = getSharedPreferences("logged", Context.MODE_PRIVATE);
final SharedPreferences.Editor e = s_logged.edit();
int temp = s_logged.getInt("activity", 0);
Log.d("main activity", " s_logged activity ="+temp );
UserInstanceClass instance_user = new UserInstanceClass();
//final Client mKinveyClient = new Client.Builder("kid_W1EFbeKyy-", "1b6f09e812114210ae4447f310b38a0a"
// , this.getApplicationContext()).build();
instance_user.setmKinveyClient(new Client.Builder(this.getApplicationContext()).build());
//final Client mKinveyClient = new Client.Builder(this.getApplicationContext()).build();
// get app properties from kinvey.properties
final TextView user_text;
user_text = (TextView) findViewById(R.id.user_id);
// check if new to app
boolean meow = instance_user.mKinveyClient.user().isUserLoggedIn();
Log.i("main activity", "meow = " + meow);
int is_logged = s_logged.getInt("logged",0);
Log.d("main activity", " s_logged logged ="+is_logged);
// if already logged
if(meow){
Log.i(TAG, "(not first time): " + instance_user.mKinveyClient.user().getId());
user_text.setText("user id is " + instance_user.mKinveyClient.user().getId());
int a = s_logged.getInt("activity", 2);
Log.d(TAG, "activity going to :" + a);
Intent i = new Intent(MainActivity.this, com.example.ramapriyasridharan.trialapp04.MainQuestionsActivity.class);
i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_MULTIPLE_TASK);
// switch(a){
// case 1: i = new Intent(this, MainActivity.class);break;
// case 2: i = new Intent(this, ProfilingFeaturesActivity.class);break;
// case 4: i = new Intent(this, ProfilingSensorsActivity.class);break;
// case 5: i = new Intent(this, ProfilingDataCollectorsActivity.class);break;
// case 6: i = new Intent(this, ProfilingContextsActivity.class);break;
// case 7: i = new Intent(this, QuestionsActivity.class);break;
// case 8: i = new Intent(this, PauseActivity.class);break;
// case 9: i = new Intent(this, MainQuestionsActivity.class);break;
// }
startActivity(i);
}
// if user is logged in meow = True dont log him in again!
if (!meow) {
instance_user.mKinveyClient.user().login(new KinveyUserCallback() {
@Override
public void onFailure(Throwable error) {
Log.i(TAG, "Fail");
user_text.setText("User not identified !!");
Log.i(TAG, "" + error);
}
@Override
public void onSuccess(User result) {
user_text.setText("user id is " + result.getId());
e.putInt("logged",1); // means it is logged in
e.commit();
Log.i(TAG, "Logged in a new implicit user with id(first time): " + result.getId());
}
});
}
String user_string = instance_user.mKinveyClient.user().getId();
Log.i(TAG, "running for first time");
// Reset preferences file when installing application for the first time
// remove only debugging!
SharedPreferences s = getSharedPreferences("bid_window_values", Context.MODE_PRIVATE);
SharedPreferences.Editor editor = s.edit();
editor.putInt("current_question_number",0);
editor.putInt("current_day",1);
editor = AddDouble.putDouble(editor,"current_credit",0);
editor = AddDouble.putDouble(editor,"current_privacy",100);
editor.commit();
// clear content to simulate first time user
db.removeAll();
Intent intent = new Intent(this, GetUserInformation.class);
e.putInt("activity", 2);
e.commit();
intent.putExtra("user_id",user_string);
startActivity(intent);
}
这是第一个在打开应用程序后调用的活动，它通常会转到下一个活动getUserInformation，但是如果用户已经登录并使用了该应用程序，则应该查看用户的最后位置并转到那里。 / p>
我使用数字保存状态的方式参考每个活动，正如您在切换案例中看到的那样（保存在首选项文件中），不幸的是从if内部调用任何活动似乎对我有效。
答案 0 :(得分：1)
正如所建议的，这是我的答案。首先，我觉得你的代码实际上是杂乱无章的 - 你应该花一些时间来清理它 - 最重要的是，你应该将大部分代码移到一些辅助函数中。另外，请删除使用SharedPreferences的所有代码 - 我真的不明白为什么你有这个代码。
请参阅下面我建议的更改，希望能帮助您解决问题：
public class MainActivity extends AppCompatActivity {
StoreDbHelper db = null;
SharedPreferences.Editor s_loggedEditor = null;
private static String TAG = MainActivity.class.getName();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
DatabaseInstance d = new DatabaseInstance(this);
db = DatabaseInstance.db;
// do not let screen switch off
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
UserInstanceClass instance_user = new UserInstanceClass();
instance_user.setmKinveyClient(new Client.Builder(this.getApplicationContext()).build());
final TextView user_text;
user_text = (TextView) findViewById(R.id.user_id);
// check if new to app
boolean meow = instance_user.mKinveyClient.user().isUserLoggedIn();
Log.i("main activity", "meow = " + meow);
// if already logged
if(meow){
Log.i(TAG, "(not first time): " + instance_user.mKinveyClient.user().getId());
user_text.setText("user id is " + instance_user.mKinveyClient.user().getId());
Intent i = new Intent(MainActivity.this, com.example.ramapriyasridharan.trialapp04.MainQuestionsActivity.class);
i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_MULTIPLE_TASK);
startActivity(i);
}
else{
//instead of if (!meow){}...just use ELSE
instance_user.mKinveyClient.user().login(new KinveyUserCallback() {
@Override
public void onFailure(Throwable error) {
Log.i(TAG, "Fail");
user_text.setText("User not identified !!");
Log.i(TAG, "" + error);
}
@Override
public void onSuccess(User result) {
user_text.setText("user id is " + result.getId());
Log.i(TAG, "Logged in a new implicit user with id(first time): " + result.getId());
//now you can do whatever you wanted to do when the user logs in for the first time
processFirstTimeLogin();
//Here I am just assuming you wanted to show the GetUserInformation Activity
String user_string = result.getId();
Log.i(TAG, "running for first time");
showGetUserInformationIntent(user_string);
}
});
}
}
//I just moved some of the code here
private void processFirstTimeLogin(){
//THE REST OF YOUR CODE
// Reset preferences file when installing application for the first time
// remove only debugging!
SharedPreferences s = getSharedPreferences("bid_window_values", Context.MODE_PRIVATE);
SharedPreferences.Editor editor = s.edit();
editor.putInt("current_question_number",0);
editor.putInt("current_day",1);
editor = AddDouble.putDouble(editor,"current_credit",0);
editor = AddDouble.putDouble(editor,"current_privacy",100);
editor.commit();
// clear content to simulate first time user
db.removeAll();
}
//Here you show the other Intent
private void showGetUserInformationIntent(String userString){
Intent intent = new Intent(this, GetUserInformation.class);
s_loggedEditor.putInt("activity", 2);
s_loggedEditor.commit();
intent.putExtra("user_id",userString);
startActivity(intent);
}