Develop Reference

How to disable and enable the the overflow Button on different fragments

I have and application in which I am using the Single activity and different fragments let say on activity start I call fragment A , and then after taking inputs I switch to fragment B and then Fragment C .
For Some reasons I have changed the Overflow Icon successfully from styles. But now The only problem is that for some reasons I want to show the overflow icons on Fragment B but not on Fragment A and C . for this I am doing this
public static void setOverflowButtonColor(final Activity activity, final int i) {
final String overflowDescription = activity.getString(R.string.abc_action_menu_overflow_description);
final ViewGroup decorView = (ViewGroup) activity.getWindow().getDecorView();
final ViewTreeObserver viewTreeObserver = decorView.getViewTreeObserver();
viewTreeObserver.addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
TintImageView overflow = null;
final ArrayList<View> outViews = new ArrayList<View>();
decorView.findViewsWithText(outViews, overflowDescription,
View.FIND_VIEWS_WITH_CONTENT_DESCRIPTION);
if (outViews.isEmpty()) {
return;
}
overflow = (TintImageView) outViews.get(0);
//overflow.setColorFilter(Color.CYAN);
overflow.setImageResource(R.drawable.my_overflow_image);
if (i == 1 && overflow!=null) {
overflow.setEnabled(false);
overflow.setVisibility(View.GONE);
} else if (overflow != null) {
overflow.setEnabled(true);
overflow.setVisibility(View.VISIBLE);
}
overflow.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Toast.makeText(activity, "Overflow", Toast.LENGTH_SHORT).show();
}
});
removeOnGlobalLayoutListener(decorView, this);
}
});
}
public static void removeOnGlobalLayoutListener(View v, ViewTreeObserver.OnGlobalLayoutListener listener) {
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN) {
v.getViewTreeObserver().removeGlobalOnLayoutListener(listener);
}
else {
v.getViewTreeObserver().removeOnGlobalLayoutListener(listener);
}
}
So from Fragment A I am sending 1 in parameter so to hide the Icon but from Activity B I am sending 0 in parameter to re visible it , but it is not getting call.
Let me tell you this function working when it is called from Fragment A , I mean it is calling one time but not 2nd time or so on .
please tell me how to do this , if you know any other best method

Define an interface like below.
public interface FragmentHost{
public void onFragmentChange(int currentFragment);
}
Activity A should implement this interface.
class A extends Activity implents FragmentHost {
public static final int FRAGMENT_B = 0;
public static final int FRAGMENT_C = 1;
#Override
public void onFragmentChange(int currentFragment) {
if (currentFragment == FRAGMENT_A) {
// enable or disable button
} else if(currentFragment == FRAGMENT_B) {
// enable or disable button
}
}
}
And in each fragment . OnResume function call the onFragmentChange() method and pass the fragment id.
class B extends Fragment {
#Override
public void onResume() {
((FragmentHost) getParentActivity()).onFragmentChange(A.FRAGMENT_B);
}
}

Understanding and fixing instance handling between classes

Im having issues with the app crashing with nullpoint exception.
I know that it crashes when trying to get an ArrayList from pictureTalkFragment. which in this class is only set to PictureTalkFragment ptf;
In other words im trying to get an element (have both getter/setter for the arraylist in ptf, and made the arraylist public as an alternative) from an class and not the instance of that class.
But im just to noob to figure out how to correctly handle getting the instances between classes (activity ---> fragments and back etc). In Java i usually just had an referance in the Constructor that sent the instance/referance with the creation of the new class. But in Android theres all this onCreate (getActivity,getContext ++), Im confused:P When to user where and how:(
the EditPicture was started from this code in GridViewAdapter that extended from PictureTalkFragment (edit in onlongclicklistener)
row.setOnLongClickListener(new View.OnLongClickListener()
{
#Override
public boolean onLongClick(View v) {
PopupMenu popMenu = new PopupMenu(v.getContext(), v);
popMenu.getMenuInflater().inflate(R.menu.picturetalk_popup_menu, popMenu.getMenu());
popMenu.setOnMenuItemClickListener(new PopupMenu.OnMenuItemClickListener() {
#Override
public boolean onMenuItemClick(MenuItem menuItem) {
switch (menuItem.getItemId()) {
case R.id.edit:
Intent intent = new Intent(getContext(), EditPicture.class);
intent.putExtra("itemUUID", item.getId());
String s = new String("");
context.startActivity(intent);
break;
case R.id.remove:
FileInteraction fileInteraction = new FileInteraction();
fileInteraction.deleteFilesAndFolder(item.getImagePath());
item.setTitle("");
notifyDataSetChanged();
break;
default:
//
}
return true;
}
});
popMenu.show();
return true;
}
});
return row;
EditPicture class
public class EditPicture extends Activity {
private EditText text;
private Button applyBtn;
private ArrayList<PictureItem> piArray;
private PictureItem pi;
private UUID itemID;
private PictureTalkFragment ptf;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
itemID = (UUID) getIntent().getSerializableExtra("itemUUID");
SetLocalArray(ptf.getArray()); //Nullpoint here, and i know why. But not how to get the allready created instance of this class
getPictureItem();
setContentView(R.layout.picturetalk_edit_pic);
text = (EditText) findViewById(R.id.editName);
text.setText(pi.getTitle());
applyBtn = (Button) findViewById(R.id.applyChangeBtn);
applyBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
updatePictureItem();
ptf.setArray(piArray);
}
});
}
private void updatePictureItem() {
pi.setTitle(text.toString());
piArray.add(pi);
ptf.setArray(piArray);
}
private void SetLocalArray(ArrayList<PictureItem> array) {
this.piArray = array;
}
private PictureItem getPictureItem() {
pi = new PictureItem("", "");
for (int i = 0; i < piArray.size(); i++) {
if (itemID.equals(piArray.get(i))) {
pi = piArray.get(i);
piArray.remove(i);
}
}
return pi;
}}

I don't know what you are using the array for.
Usually you should not depend on the fragment to get the info, if you want to pass an array of objects to the activity, you should use the Bundle in the activity extras to do so, instead of passing only the UUID, just pass also the array you need.
If you want the lazy option just make a class with a static variable to store the fragment and use it in the activity, which I don't advise.

Tab Disappear when start new activity

I am developing android application which having multiple tabs.
Now in launcher activity tabs display perfectly and can navigate through the tabs.
but if i call activity(which i wanted to show as Tab) on Button Clicked then tabs seems disappear.
please refer the given code and let me know if i am doing something wrong.
This is Main TabActivity
public class MyTabActivity extends TabActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_tab);
TabHost tabHost=getTabHost();
TabSpec deshTab=tabHost.newTabSpec("Deshboard");
deshTab.setIndicator("Deshboard");
Intent DeshboardIntent=new Intent(this,DeshboardActivity.class);
deshTab.setContent(DeshboardIntent);
tabHost.addTab(deshTab);
TabSpec clientTab=tabHost.newTabSpec("client");
clientTab.setIndicator("client");
Intent intent=new Intent(this,ClientActivity.class);
clientTab.setContent(intent);
tabHost.addTab(clientTab);
}
}
Now i wanted to start client activity like
void onButtonClick(View view)
{
int id = view.getId();
switch(id)
{
case R.id.client_btn:
Intent clientIntent = new Intent(DeshboardActivity.this,ClientActivity.class);
startActivity(clientIntent);
break;
}
}
but when i click this button it starts new activity but NOT in tab.
what should i do to display this activity in tab on button click also.?
Below code is ClientActivity which i wanted to display as TAB.
public class ClientActivity extends Activity
{
private DatabaseHandler dbHandler;
private ListView clientListView ;
private BaseAdapter listAdapter;
TabHost tabHost;
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.clientactivity);
dbHandler = new DatabaseHandler(this);
final List<Client> clientList = dbHandler.getAllclient();
clientListView = (ListView)findViewById(R.id.client_list);
listAdapter = new ClientListAdapter(this, clientList);
clientListView.setAdapter(listAdapter);
clientListView.setOnItemClickListener(new OnItemClickListener()
{
#Override
public void onItemClick(AdapterView<?> parent, View view,int position, long id)
{
Client client = clientList.get(position);
Toast.makeText(getApplicationContext(), client.getFirstName(), Toast.LENGTH_LONG).show();
Intent clientInfoIntent = new Intent(getApplicationContext(), ClientInfoActivity.class);
clientInfoIntent.putExtra("client",client);
startActivity(clientInfoIntent);
//finish();
}
});
}
}

That's because your ClientActivity is launched on top of your TabActivity. That way your tabbar is not shown anymore.
I suggest you use fragments for your ClientActivity.
A tutorial how to use fragments:
http://developer.android.com/guide/components/fragments.html

Drilldown navigation in Android tabhost

I have an android tabhost with a listview inside, when I click on a listviewitem I want to show a new list at the place of the old list inside the tablayout.
How can I implement this? (I need to use listviews not fragments)
Thanks!

I found a solution: I put an activitygroup inside the tabhost, like so:
public class DrillDownWrapper extends ActivityGroup {
private ArrayList<View> history;
public static DrillDownWrapper group;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
history = new ArrayList<View>();
group = this;
//put the first listactivity
Intent i = new Intent(DrillDownWrapper.this, ListActivity.class);
View view = getLocalActivityManager().startActivity("ListActivity", i.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP)).getDecorView();
replaceView(view);
}
public void replaceView(View v) {
history.add(v);
setContentView(v);
}
public void back() {
if(history.size() > 1) {
history.remove(history.size()-1);
setContentView(history.get(history.size()-1));
} else {
finish();
}
}
#Override
public void onBackPressed() {
DrillDownWrapper.group.back();
return;
}
}
inside the listactivity you can get the context (ie to show a dialog) by calling getParent() method

Android: Create a new intent with a button from a GridView (GridView with Navigation buttons)

I have created a class of type BaseAdapter that is populated with buttons - when you click on a button I want to load a new intent. This has proven difficult on two levels:
You cannot associate the event with the button (one that creates a new intent) inside the Adapter. This is why I send the Buttons as an array to my Adapter (this solution works, but it is messy)
Even though my buttons are created inside the same Activity - they cannot create a new intent from that Activity. The exeption is so great that I have not even gotten a try...catch statement to work.
I have tried reflection, creating the buttons inside the activity and passing them through, passing the context (to call context.startIntent(...))
My question: can someone show me how to create a ButtonAdapter where each button creates a new Intent - even of the same type as the original Activity?
UPDATE: Here is the code because I am getting answers from people who think I am struggling with onClickListeners:
public class ButtonAdapter extends BaseAdapter
{
private Context _context;
private Button[] _button;
public ButtonAdapter(Context c, Button[] buttons)
{
_context = c;
_button = buttons;
}
// Total number of things contained within the adapter
public int getCount()
{
return _button.length;
}
// Require for structure, not really used in my code.
public Object getItem(int position)
{
return _button[position];
}
// Require for structure, not really used in my code. Can
// be used to get the id of an item in the adapter for
// manual control.
public long getItemId(int position)
{
return position;
}
public View getView(int position, View convertView, ViewGroup parent)
{
_button[position].setId(position);
return _button[position];
}
}
---------------
The Activity:
public class MainActivity extends Activity
{
private GridView _gv;
private TextView _heading;
private ButtonAdapter _adapter;
public void LoadActivity(String heading)
{
try
{
Itent intent = new Intent(getApplicationContext(), MainActivity.class);
intent.putExtra("Level", "NextPage");
intent.putExtra("Heading", heading);
startActivity(intent);
}
catch (Exception ex)
{
Toast.makeText(getApplicationContext(), String.format("Error LoadActivity: %s", ex.getMessage()), Toast.LENGTH_SHORT).show();
}
}
private void createButtonsAdapter(Button _button[])
{
_buttonadapter = new ButtonAdapter(getApplicationContext(), _button);
_gv.setAdapter(_adapter);
}
private void setupButtons()
{
Button[] _buttons = new Button[2];
String names[] = new String[]{"Button1","Button2"};
for (int i = 0; i < 2; i++)
{
_buttons[i] = new Button(this);
_buttons[i].setText(names[i]);
_buttons[i].setTag(names[i]);
_buttons[i].setOnClickListener(new View.OnClickListener()
{
public void onClick(View arg0)
{
try
{
LoadActivity(((Button)arg0).getTag().toString());
}
catch(Exception ex)
{
Toast.makeText(getApplicationContext(), String.format("Error button.onClick: %s", ex.getMessage()), Toast.LENGTH_SHORT).show();
}
}
});
}
createButtonsAdapter(_buttons);
}
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
_gv = (GridView)findViewById(R.id.gridview);
_heading = (TextView)findViewById(R.id.tv_heading);
Bundle params = getIntent().getExtras();
if (params == null)
{
setupButtons();
}
else if (params.containsKey("Level"))
{
_heading.setText(params.getString("Heading"));
if (params.getString("Level").equals("NextPage"))
{
//code not here yet
}
else if (params.getString("Level").equals("Chapters"))
{
//future code
}
}
}
}
Excuse the bold and caps but I have had enough silly answers to warrent this:
I HAVE TRIED PUTTING THE ONCLICKLISTENER INSIDE THE GRIDVIEW AND IT DOES NOT WORK EITHER
You cannout load an activity from a class outside that activity, even if you pass the context as a parameter. That is why I have resorted to this method, which completely bombs android, even though I have try catch statements.
Please try give me a solution in the form of a correction to my code, other code, or a tutorial that achieves what I want here. I know how to do a button adapter properly, it is the act of loading an Intent that has forced me to implement it this way.

I suggest the following,
Using a common onClick listner for all the buttons in your grid view
Set tag for all the butons in the getView func. of adapter.
Use the tag Object to decide on the intent to fire from the onClick listener.
I hope it helps..

I guess you can easily manipulate your buttons created in your class extending Base adapter. In the getView method .... if you have button b.. then do it as follows
b.setOnClickListener(new OnClickListener()
{
public void onClick()
{
// Do your stuff here ...
}
});
and if you want to start another activity on Click of this button then you need to pass the calling context to this adapter.

Once again I am answering my own question:
http://bottlecapnet.blogspot.com/2012/01/android-buttons-have-no-place-inside.html
I will just have to style TextViews as I want to see them.