Develop Reference

Button visible and invisible

I am new in android app development.
I am searching an example like bellow:
There is a checkbox and two buttons named btn1 and btn2.
Logic should be when user will checked on the checkbox then btn2 will visible and btn1 will invisible.
In my XML file:
<android.support.design.widget.TextInputLayout
android:id="#+id/input_layout_provider"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<android.support.v7.widget.AppCompatCheckBox
android:id="#+id/input_chk_provider"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:checked="false"
android:duplicateParentState="false"
android:text="#string/user_type_provider" />
</android.support.design.widget.TextInputLayout>
<Button
android:id="#+id/btn_signup"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/btn_sing_up"
android:background="#color/ic_launcher_background"
android:layout_marginTop="40dp"
android:textColor="#android:color/white"/>
<Button
android:id="#+id/btn_provider"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/btn_provider_dtl"
android:background="#color/ic_launcher_background"
android:layout_marginTop="40dp"
android:textColor="#android:color/white"/>

Without having the code...
You'll need a OnCheckedChangeListener for the Checkbox so you can adjust the button visibility when it's checked/unchecked.
Something like:
checkBox.setOnCheckedChangeListener(new OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if(isChecked) {
btn1.setVisibility(View.GONE);
btn2.setVisibility(View.VISIBLE);
} else {
btn1.setVisibility(View.VISIBLE);
btn2.setVisibility(View.GONE);
}
});

In your XML use android:visibility="invisible" to set the visibility of the buttons.
In the code, get your views with findViewById()
CheckBox checkBox = (CheckBox) findViewById(R.id.check1);
Button yourButton = (Button) findViewById(R.id.btn1);
checkBox.setOnCheckedChangeListener(new OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton button, boolean isChecked) {
if(isChecked){
yourButton.setVisibility(View.VISIBLE);
} else {
yourButton.setVisibility(View.INVISIBLE);
}
}
});
Use the method .setVisibility(View.VISIBLE) to change the visibility.
There are 3 states:
View.GONE
View.VISIBLE
View.INVISIBLE

Checkbox has OnCheckedChangeListener() method which will give you the state of the checkbox. Based on the state of the Checkbox you can use Button1.setVisibility(true/false); to show/hide the button.

try this..
<CheckBox
android:id="#+id/input_chk_provider"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:state_checked="true"
android:checked="false"
android:onClick="itemClicked"
android:duplicateParentState="false" />
public void itemClicked(View v) {
//code to check if this checkbox is checked!
CheckBox checkBox = (CheckBox)v;
if(checkBox.isChecked()==true){
bt1.setVisibility(View.VISIBLE);
bt2.setVisibility(View.INVISIBLE);
}else if(checkBox.isChecked()==false){
bt2.setVisibility(View.VISIBLE);
bt1.setVisibility(View.INVISIBLE);
}
}

How to get and populate a menu item created through custom layout?

I've been trying to load an image into a menu item which has been created through a custom layout and have been checking on the official documentation and on posts such as these Custom view for Menu Item but..
That's my onCreateOptionsMenu ond OnPrepareOptionsMenu
#Override
public boolean onPrepareOptionsMenu(Menu menu) {
final MenuItem alertMenuItem = menu.findItem(R.id.action_my_personal);
FrameLayout rootView = (FrameLayout) alertMenuItem.getActionView();
redCircle = (FrameLayout) rootView.findViewById(R.id.view_alert_red_circle);
countTextView = (TextView) rootView.findViewById(R.id.view_alert_count_textview);
ImageView hc_image_menu_inflated = (ImageView) rootView.findViewById(R.id.hc_image_menu);
rootView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
onOptionsItemSelected(alertMenuItem);
}
});
if (menu.findItem(R.id.hc_image_menu) != null) {
loadMenuIcon(menu.findItem(R.id.hc_image_menu), my_image_url);
}
return super.onPrepareOptionsMenu(menu);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.toolbar_menu_main, menu);
return true;
}
As you can see I have added these lines to avoid the app crashing, as menu.finditem(R.id.hc_image_menu) is returning as null and that's where the problem is, as I want to populate the ImageView that has the id hc_image_menu but am not being successful despite so many attempts
if (menu.findItem(R.id.hc_image_menu) != null) {
loadMenuIcon(menu.findItem(R.id.hc_image_menu), my_image_url);
}
My code for my toolbar_main_menu layout is this:
<item
android:id="#+id/action_my_personal"
app:actionLayout="#layout/toolbar_menu_hc"
android:orderInCategory="100"
android:title="My Personal Trainer"
app:showAsAction="always" />
And for my custom layout (toolbar_hc_menu) is this one:
<FrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="48dp"
android:layout_height="32dp"
android:layout_gravity="center">
<ImageView
android:id="#+id/hc_image_menu"
android:layout_marginRight="8dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:src="#drawable/gavin"/>
<FrameLayout
android:id="#+id/view_alert_red_circle"
android:layout_width="14dp"
android:layout_height="14dp"
android:layout_gravity="top|end"
android:background="#drawable/date_circle"
android:visibility="gone"
tools:visibility="visible">
<TextView
android:id="#+id/view_alert_count_textview"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:textColor="#color/white"
android:textSize="10sp"
tools:text="3"/>
</FrameLayout>
Thanks very much for any help on that. Really much appreciated!! :)

Issue fixed. :)
At the end I just had to load the image into the ImageView after having got the alertMenuItem.
if (my_image_url!= null) {
Picasso.with(getApplicationContext()).load(my_image_url).into(hc_image_menu_inflated);
}

TextView in menu is always null after orientation change

I have a TextView functioning as a notification badge on a menu item. The problem is that the findViewById method always returns null after an orientation change, so when I try to modify its visibility with setVisibility it throws a NullPointerException. I've tried calling the onCreateOptionsMenu again by calling invalidateOptionsMenu in onRestart but it doesn't appear to help.
From what I can tell every other view is found and it's just this TextView that is being a nuisance.
The part where it crashes (this is called in onCreate) :
public void updateUnreadNotificationCount(final int unreadNotificationsCount) {
unreadNotificationCount = unreadNotificationsCount;
if (unreadNotificationCount == 0) {
notificationCounter.setVisibility(View.INVISIBLE);
}else {
notificationCounter.setVisibility(View.VISIBLE);
notificationCounter.setText(String.valueOf(unreadNotificationCount));
}
}
How the Textview gets created:
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
View count = menu.findItem(R.id.action_notifications).getActionView();
notificationCounter = (TextView) count.findViewById(R.id.textview_notification_count);
count.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent i = new Intent(mCtx, NotificationListActivity.class);
startActivity(i);
}
});
notificationCounter.setText(String.valueOf(unreadNotificationCount));
return super.onCreateOptionsMenu(menu);
}
The XML for the menu item:
<item
android:id="#+id/action_notifications"
android:title="#string/action_notifications"
android:icon="#drawable/ic_mail_white_48dp"
android:actionLayout="#layout/actionbar_notification_icon"
android:showAsAction="always"
app:showAsAction="always"
android:orderInCategory="60"/>
The action layout for the TextView:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:clickable="true"
style="#android:style/Widget.ActionButton">
<ImageView
android:id="#+id/imageview_notification"
android:src="#drawable/ic_mail_white_48dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="center"
android:layout_margin="0dp"/>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/textview_notification_count"
android:layout_width="wrap_content"
android:minWidth="17sp"
android:textSize="12sp"
android:textColor="#ffffffff"
android:layout_height="wrap_content"
android:gravity="center"
android:text="#null"
android:layout_alignTop="#id/imageview_notification"
android:layout_alignRight="#id/imageview_notification"
android:layout_marginRight="0dp"
android:layout_marginTop="3dp"
android:paddingBottom="1dp"
android:paddingRight="4dp"
android:paddingLeft="4dp"
android:background="#drawable/rounded_square"/>
</RelativeLayout>

Managed to fix the issue by moving the initialization of the TextView into onPrepareOptionsMenu and calling invalidateOptionsMenu() during onResume().

Android actoin bar get valules from linked layout

My android application has an action bar item to add employees.
So here what I did is call custom layout named add_employee when this action bar item clicked.
<item android:id="#+id/action_add"
android:icon="#drawable/ic_action_add_person"
android:title="#string/action_add"
android:showAsAction="ifRoom|collapseActionView"
android:actionLayout="#layout/add_employee"/>
Following image shows that custom layout:
This is a loyout xml file named add_employee. Add and cross marks are image views.
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ImageView
android:id="#+id/imageView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignTop="#+id/imageView1"
android:layout_marginRight="12dp"
android:src="#drawable/ic_action_cancel" />
<EditText
android:id="#+id/editText1"
android:layout_width="228dp"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_marginRight="40dp"
android:layout_toLeftOf="#+id/imageView1"
android:ems="10"
android:inputType="numberSigned" />
<ImageView
android:id="#+id/addemp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBottom="#+id/editText1"
android:layout_marginRight="26dp"
android:layout_toLeftOf="#+id/imageView2"
android:src="#drawable/ic_action_add_person" />
</RelativeLayout>
Now I want to get the entered value to this edit text field when add image view clicked. This operation should be handled in the same java class where I set the option menu also.
public class MainPortal extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main_portal);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu items for use in the action bar
MenuInflater inflater = getMenuInflater();
// Inflate the menu; this adds items to the action bar if it is present.
inflater.inflate(R.menu.main_portal, menu);
return super.onCreateOptionsMenu(menu);
}
}
I have used setOnItemClickListener for imge view but it ends with a forced closed error. How can I do this task?
Please help me...
Thanks in advanced.

Did you create the actions in onOptionsItemSelected? Where is the code showing the implementation of the Action bar tabs?
this is how to implement an option on actionbar
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle presses on the action bar items
switch (item.getItemId()) {
case R.id.action_search:
openSearch();
return true;
case R.id.action_compose:
composeMessage();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
there you can implement whatever and however...
plus showing more code and LogCat would help understanding your exact issue

How to do something when a checkbox change state?

This is my code:
<CheckBox
android:id="#+id/sprint_checkbox"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/sprint_game" />
<CheckBox
android:id="#+id/marathon_checkbox"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/marathon" />
<CheckBox
android:id="#+id/never_ending_checkbox"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/never_ending" />
What i want to do is "detect" when one of these is checked and then set the other two to "disable", so the user can select only one at time.
I tried to use the ".setOnCheckedChangeListener", but i can't do that, can someone help me with some code?
Thanks a lot guys!

This is the way you are notified about checked changes:
CheckBox check = findViewById(R.id.sprint_checkbox);
check.setOnCheckedChangeListener(new OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
//do stuff
}
});
You can also let your activity implements the OnCheckedChangeListener interface and then:
CheckBox check1 = findViewById(R.id.sprint_checkbox);
CheckBox check2 = findViewById(R.id.marathon_checkbox);
CheckBox check3 = findViewById(R.id.never_ending_checkbox);
check1.setOnCheckedChangeListener(this);
check2.setOnCheckedChangeListener(this);
check3.setOnCheckedChangeListener(this);
Overriding the interface method:
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
switch(buttonView.getId()){
case R.id.sprint_checkbox:
//do stuff
break;
case R.id.marathon_checkbox:
//do stuff
break;
case R.id.never_ending_checkbox:
//do stuff
break;
}
}

I believe a RadioButton would be more suitable for your aims.
<RadioGroup
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:id="#+id/radio_group1">
<RadioButton
android:id="#+id/sprint"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/rad_option1"
android:checked="true"
android:onClick="onRadioButtonClick"
/>
<RadioButton
android:id="#+id/marathon"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/rad_option2"
android:onClick="onRadioButtonClick"
/>
<RadioButton
android:id="#+id/neverending"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/rad_option3"
android:onClick="onRadioButtonClick"
/>
</RadioGroup>
Then in your code:
public void onRadioButtonClick(View v) {
RadioButton button = (RadioButton) v;
// DO YOUR THING HERE DEPENDING ON WHICH RADIOBUTTON IS PICKED
}
In this case, you won't have to deal with disabling other options. The user will have only one option to pick by default.

#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
int id = buttonView.getId();
if(isChecked){
switch(id){
case R.id.sprint:
//add to database
...
}
}
else{
switch(id){
case R.id.sprint:
//remove from database
...
}
}
}
This should allow you to with ID's. Hope it works.