Apps savedInstanceState not working?

[Deleted User]

I have two Activities in my app and I've created an option menu to go back and forth between them

Example from one of the Activities:

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
    	super.onCreateOptionsMenu(menu);
    	MenuInflater inflater = getMenuInflater();
    	inflater.inflate(R.menu.menu, menu);  
    	return true;
    }
    
    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
    	super.onOptionsItemSelected(item);
    	switch(item.getItemId()) {
    		case R.id.menu_inbox:
    			Intent intentLaunchInbox = new Intent(ActivityLogin.this, ActivityInbox.class);
        		startActivity(intentLaunchInbox);
    			break;
    	}
    	return true;
    }

I've overridden the onSaveInstanceState and onRestoreInstanceState handlers. Here's an example from my login Activity:

    @Override
    protected void onSaveInstanceState(Bundle outState) {    	
    	// save screen state
    	outState.putString(LOGIN_USER_NAME, m_txtUsername.getText().toString());
    	outState.putString(LOGIN_USER_PASS, m_txtPassword.getText().toString());
    	outState.putSerializable(LOGIN_STATE_MODEL, m_smLogin);
    	super.onSaveInstanceState(outState);
    }
    
    @Override
    public void onRestoreInstanceState(Bundle savedInstanceState)
    {
        super.onRestoreInstanceState(savedInstanceState);
        
        // restore screen state
        if (savedInstanceState != null) {
        	if (savedInstanceState.containsKey(LOGIN_USER_NAME)) {
        		m_txtUsername.setText((String)savedInstanceState.getString(LOGIN_USER_NAME));
        	}
        	if (savedInstanceState.containsKey(LOGIN_USER_PASS)) {
        		m_txtPassword.setText((String)savedInstanceState.getString(LOGIN_USER_PASS));
        	}
        	if (savedInstanceState.containsKey(LOGIN_STATE_MODEL)) {
        		m_smLogin = (StateModel)savedInstanceState.getSerializable(LOGIN_STATE_MODEL);
        		// if thread is still running, throw up another progress dialog
        		if (m_smLogin.getState() == StateModel.State.RUNNING) {
            		m_pdProgress = ProgressDialog.show(ActivityLogin.this, "", getString(R.string.logging_in), true);
        		}
        	}
        }
        updateDisplay();
    }

When I navigate away from the login Activity, it's onSaveInstanceState gets called and the State is written.

If I click the BACK button on the emulator, it goes back to the login screen and everything is populated (onRestoreInstanceState is not called. it's like it just goes back to a saved screen on the stack). However, if I click the MENU button to open the options menu, a new login Activity is created and the savedInstanceState is null (and onRestoreInstanceState is never called).


What's going on? How do I make this work right?

 

[Deleted User]

Ah, so the restore only happens if the Activity was killed.

The way I am going about going back and forth is really creating new Activities on the Activity stack. What I need to do is tell my Intent to pull the existing Activity off the history stack and move it to the front.

The needs to be doing similar to

Intent.setFlag(Intent.FLAG_ACTIVITY_BROUGHT_TO_FRONT);

before starting the Activity.

Unfortunately, it's not working It is creating a new Activity on the stack. How do I make this work?

 

[Deleted User]

android:launchMode="singleInstance"

 

[Deleted User]

Hmm

This presents a new issue...

Is there a programmatic way to go through all the Activities on the Activity stack and destroy them?

 

[markb]

Hi andywhoa

I haven't tried it myself, but is this any use to you?

There's a noHistory attribute

<activity> | Android Developers

A value of "true" means that the activity will not leave a historical trace. It will not remain in the activity stack for the task, so the user will not be able to return to it.

Mark

 

[cp1]

Does your ActivityLogin have to keep running, or is it done once it logs you in? If it finishes it should kill itself when the memory is needed.

 

[KennethWindish]

I have two Activities in my app and I've created an option menu to go back and forth between them

Example from one of the Activities:

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
    	super.onCreateOptionsMenu(menu);
    	MenuInflater inflater = getMenuInflater();
    	inflater.inflate(R.menu.menu, menu);  
    	return true;
    }
    
    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
    	super.onOptionsItemSelected(item);
    	switch(item.getItemId()) {
    		case R.id.menu_inbox:
    			Intent intentLaunchInbox = new Intent(ActivityLogin.this, ActivityInbox.class);
        		startActivity(intentLaunchInbox);
    			break;
    	}
    	return true;
    }

I've overridden the onSaveInstanceState and onRestoreInstanceState handlers. Here's an example from my login Activity:

    @Override
    protected void onSaveInstanceState(Bundle outState) {    	
    	// save screen state
    	outState.putString(LOGIN_USER_NAME, m_txtUsername.getText().toString());
    	outState.putString(LOGIN_USER_PASS, m_txtPassword.getText().toString());
    	outState.putSerializable(LOGIN_STATE_MODEL, m_smLogin);
    	super.onSaveInstanceState(outState);
    }
    
    @Override
    public void onRestoreInstanceState(Bundle savedInstanceState)
    {
        super.onRestoreInstanceState(savedInstanceState);
        
        // restore screen state
        if (savedInstanceState != null) {
        	if (savedInstanceState.containsKey(LOGIN_USER_NAME)) {
        		m_txtUsername.setText((String)savedInstanceState.getString(LOGIN_USER_NAME));
        	}
        	if (savedInstanceState.containsKey(LOGIN_USER_PASS)) {
        		m_txtPassword.setText((String)savedInstanceState.getString(LOGIN_USER_PASS));
        	}
        	if (savedInstanceState.containsKey(LOGIN_STATE_MODEL)) {
        		m_smLogin = (StateModel)savedInstanceState.getSerializable(LOGIN_STATE_MODEL);
        		// if thread is still running, throw up another progress dialog
        		if (m_smLogin.getState() == StateModel.State.RUNNING) {
            		m_pdProgress = ProgressDialog.show(ActivityLogin.this, "", getString(R.string.logging_in), true);
        		}
        	}
        }
        updateDisplay();
    }

When I navigate away from the login Activity, it's onSaveInstanceState gets called and the State is written.

If I click the BACK button on the emulator, it goes back to the login screen and everything is populated (onRestoreInstanceState is not called. it's like it just goes back to a saved screen on the stack). However, if I click the MENU button to open the options menu, a new login Activity is created and the savedInstanceState is null (and onRestoreInstanceState is never called).


What's going on? How do I make this work right?

I believe you need to capture the key press when the back button is hit & have it save the instance.

 

[rkjhaw]

you are right andywhoa, onRestoreInstanceState never be get called.
I wrote a blog, i given a example, visit the blog.


http://www.alltechsolution.wordpress.com