Saving the State of Drawable xml Button.
private boolean mJam;
private button mSwitch;
private static final String KEY_ENABLE = "KEY_ENABLE";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if( null == savedInstanceState ) {
mJam = false;
} else {
mJam = savedInstanceState.getBoolean(KEY_ENABLE);
}
button_layout();
}
#Override
protected void onSaveInstanceState(Bundle outState) {
outState.putBoolean(KEY_ENABLE, mJam);
outState.putBoolean(KEY_ENABLE, mSwitch.isSelected()); // Saving the state of the
super.onSaveInstanceState(outState);
}
#Override
protected void onRestoreInstanceState(Bundle savedInstanceState) {
mSwitch.setSelected(savedInstanceState.getBoolean(KEY_ENABLE));
mJam = savedInstanceState.getBoolean(KEY_ENABLE);
super.onRestoreInstanceState(savedInstanceState);
}
Note: If you don't want to use ScreenSize in Android manifest, This code can be used,
If you want to do it Manually, then go for this one.
P.S: setting Screen Size in Manifest, never go to onCreate if the Orientation Change, It Just saved all the instance and display as it is, when
Android orientation Change.
Related
I want to keep the spinner position when the screen is rotated
I've looked at a few answers on here and so far have the following
Aim - Store the position of the spinner
protected void onSaveInstanceState(Bundle savedInstanceState) {
super.onSaveInstanceState(savedInstanceState);
flav1Spinner = (Spinner)findViewById(R.id.Combo_InvChoice1);
Integer flav1 = flav1Spinner.getSelectedItemPosition();
savedInstanceState.putInt("cho1", flav1);
}
Aim - Restore position
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_calculation);
Locale.setDefault(Locale.US);
if (savedInstanceState != null){
flav1Spinner = (Spinner)findViewById(R.id.Combo_InvChoice1);
Integer flav1 = savedInstanceState.getInt("cho1");
flav1Spinner.setSelection(flav1);
}
However while debugging I can see that the Integer Flav1 is getting a value assigned to it and the digit is being retrieved, however the spinner isn't changing it's position. Any suggestions?
You can do it by onSaveInstanceState(), As below
#Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putInt("yourSpinner", yourSpinner.getSelectedItemPosition());
// do this for each of your Spinner
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (savedInstanceState != null) {
yourSpinner.setSelection(savedInstanceState.getInt("yourSpinner", 0));
// do this for every text views
}
}
Check Saving Activity state, it will help you to get more details.
I am building a memory game app for a java class and i need to save which words are displayed through rotation of the device...the widgets that need to be saved and passed to the new onCreate() method are button widgets that i used setText to display the words that are being shown....can i save and pass the entire state of the application...here is my code that is obviously not working and i was hoping i could get some insight...thanks...here is my code..
private Bundle myBundle = new Bundle();
.....
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_eight);
if(savedInstanceState != null) {
savedInstanceState = myBundle;
}
......
#Override
public void onSaveInstanceState(Bundle savedInstanceState) {
super.onSaveInstanceState(savedInstanceState);
myBundle = savedInstanceState;
}
You got the semantics of using the Bundle backwards. You don't ever want to save the Bundle (or overwrite it). Just use it to serialize your own state variables into it and out of it. For example, if you want to preserve two integer variables and a string between a rotation (such that you can re-initialize the view with these members later), you could do the following:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_eight);
if(savedInstanceState != null) {
// Restore our member variables that represent activity state right here from the passed in Bundle.
_x = savedInstanceState.getInt("MyApp.X", 0);
_y = savedInstanceState.getInt("MyApp.Y", 0);
_name = savedInstanceState.getString("MyApp.NAME", "player");
// not shown - initializing the view elements with the initialized member variables.
}
......
#Override
public void onSaveInstanceState(Bundle savedInstanceState) {
// save our activity state by adding our member variables that represent activity state into the Bundle.
savedInstanceState.putInt("MyApp.X", _x);
savedInstanceState.putInt("MyApp.Y", _y);
savedInstanceState.putString("MyApp.NAME", _name);
// call the parent method *after* you have saved your state
super.onSaveInstanceState(savedInstanceState);
}
Bundle also supports arrays of simple types.
In method onSaveInstanceState add values which you want to save like below
#Override
public void onSaveInstanceState(Bundle savedInstanceState) {
savedInstanceState.putString("key","your string here");
}
and inside oncreate
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if( savedInstanceState != null ) {
System.out.println(savedInstanceState .getString("key"));
}
}
I'm struggling to recover my position in a listview on screen rotation configuration change.
Amongst the many things I've tried I came to this:
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
if (savedInstanceState == null) {
...
mVisibleItem = -1;
} else {
if (savedInstanceState.containsKey(LV_VISIBLE_ITEM)) {
mVisibleItem = savedInstanceState.getInt(LV_VISIBLE_ITEM);
}
}
setRetainInstance(true);
}
and here I'm trying to set the position in the listview
#Override
public void onResume() {
super.onResume();
if (mVisibleItem > 0) {
mlvDictionaryIndex.setSelectionFromTop(mVisibleItem, 0);
}
}
However, much to my surprise, after rotating the screen and watching mVisibleItem gets set with the correct value, in onResume I see that mVisibleItem equals -1. How come?
use onSavedInstanceState to write in the bundle the returned value of ListView.onSaveInstanceState(), and restored it onActivityCreated
#Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
if (mListView != null) {
outState.putParcelable(LISTVIEW_INTERNAL_STATE_KEY, mListView.onSaveInstanceState());
}
}
after the data are reload then you can call
mListView.onRestoreInstanceState(savedInstanceState.getParcelable(LISTVIEW_INTERNAL_STATE_KEY));
Override onSaveInstanceState such as below"
#Override
public void onSaveInstanceState(Bundle savedInstanceState) {
super.onSaveInstanceState(savedInstanceState);
savedInstanceState.putInt("pos", pos);
}
Then in your onCreate method have read the savedInstanceState to check if this is an orientation change or a new activity.
private int pos = 0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
//This is a new activity
}else{
pos = savedInstanceState.getInt("");
}
Now you have the position in the list, and you can scroll to this in configuration change.
Maybe after the data in the listview is reloaded，the code below will work.
mlvDictionaryIndex.setSelectionFromTop(mVisibleItem, 0);
So you can use post() method, just like below:
post(new Runnable() {
public void run() {
mlvDictionaryIndex.setSelectionFromTop(mVisibleItem, 0);
}
});
i have a problem with my app. if i click the button to stop the ProgressBarIndeterminate in actionbar, when i rotate the screen it reappear. can i stop it forever? thanks
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);
setContentView(R.layout.activity_main);
setProgressBarIndeterminateVisibility(true);
}
public void test(View v) {
setProgressBarIndeterminateVisibility(false);
}
sorry for my english
When you rotate your screen, the Activity gets created again (onCreate will get invoked again), so you will call setProgressBarIndeterminateVisibility(true) which will make it reappear.
To keep track of whether or not you've clicked the stop button, you will need to save the state somehow (consider implementing onSaveInstanceState and then retrieving the stored value in onCreate, or saving the state to a shared preference/database).
onSaveInstanceState --> invoked when your Activity is torn down due to the rotation
private boolean showProgressBarVisibility = true; //always show the first time
#Override
public void onCreate(Bundle savedInstanceState){
if(savedInstanceState != null && savedInstanceState.containsKey("user3744384_pressed_the_button"){
showProgressBarVisibility = false
}
setProgressBarIndeterminateVisibility(showProgressBarVisibility);
}
#Override
public void onSaveInstanceState(Bundle outState){
super.onSaveInstanceState(outState);
outState.putString("user3744384_pressed_the_button", true);
}
do something like this in onCreate:
if(savedInstanceState !=null){
setProgressBarIndeterminateVisibility(false);
}
but you should also save the state in public void onSaveInstanceState(Bundle ...).. research on how activities save their state.
when orientation changes android kills your activity and onCreate is called.. you can save your app state and restore it.
override this method to save state
#Override
public void onSaveInstanceState(Bundle savedInstanceState) {
savedInstanceState.putString(key, yourstatevariable);
}
and get your state variable in onCreate
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_one);
if (savedInstanceState != null) {
String yourstatevariable = savedInstanceState.get(key);
}
}
I have checked many posts, and as per that I have done coding for the orientation change. When orientation changes, the problem is I am not able to retrieve the entered values inside TextViews. Can anyone plz tell where did I go wrong?
Coding:
In manifest file for the corresponding activity I added:
android:configChanges="orientation|keyboardHidden"
In activity, I added the following methods:
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.home_screen);
//Initialized the widgets
}
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
//have written separate layout files for portrait and landscape
setContentView(R.layout.home_screen);
//Initialized the widgets again
retrieveSavedState(); //sets the TextViews again
}
#Override
protected void onPause() {
super.onPause();
saveState(); //save the TextView values
}
#Override
protected void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
saveState();
}
#Override
protected void onResume() {
super.onResume();
retrieveSavedState();
}
#Override
public Object onRetainNonConfigurationInstance()
{
final MyDataObject data = collectMyLoadedData();
return data;
}
the above method can be used to save any object to save data...
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
final MyDataObject data = (MyDataObject) getLastNonConfigurationInstance();
if (data == null) {
data = loadMyData();
}
...
}
and u can retreive that object in the onCreate() which will we called when orientation changes.. after reading data from that object you can use it where ever you want..
http://developer.android.com/guide/topics/resources/runtime-changes.html
http://developer.android.com/guide/topics/resources/runtime-changes.html
other mechanisms are also there but this is the best way for my knowledge.. you can also use shared preferences to store and retrieve data...
http://saigeethamn.blogspot.com/2009/10/shared-preferences-android-developer.html