Develop Reference

add toolbar menu only at specific fragments

So I have this app and in the toolbar, there is a drop-down menu and I am looking for a solution on how to show only specific items at specific fragments.
I know that I have to make a java class and link it to the menu, but how do I find out what fragment I am on?

You can move the implementation of setting the toolbar for your fragments in the activity that launches these fragments. In that case, you may have the toolbar in your activity and the activity should have a fragment container where you will put your fragment. Let us consider a layout like the following for your activity.
<RelativeLayout>
<!-- Your toolbar here in the activity -->
<ToolBar>
android:id="+#id/toolbar"
...
</ToolBar>
<!-- Your fragment container here -->
<FrameLayout>
android:id="+#id/fragment_container"
...
android:layout_below="#id/toolbar"
</FrameLayout>
</RelativeLayout>
Now, you have the ToolBar here in your activity and hence, you can set the toolbar when you are loading the fragments in the fragment container. Your activity might have the following functions.
public void launchFrag1() {
// replace the fragment 1 in the fragment container
loadToolbarForFrag1();
}
public void launchFrag2() {
// replace the fragment 2 in the fragment container
loadToolbarForFrag2();
}
Now call the specific function of your activity to load the fragment and the toolbar dynamically as well.
If you are trying to call the method from the fragment, you can always call those methods declared in your activity like the following.
((YourActivity) getActivity()).launchFrag2();
I hope you get the idea.
Please note that this is just a basic implementation of how you can get your dynamic toolbar working in your app. However, your implementation might vary based on the use case that you have.
I hope that helps!

I have an ImageView in the toolbar which I hide as follows:
// Show image in fragment 1
ImageView img = getActivity().findViewById(R.id.toolbarMenu);
img.setVisibility(View.VISIBLE);
// hide image in fragment 2
ImageView img = getActivity().findViewById(R.id.toolbarMenu);
img.setVisibility(View.GONE);
Try these codes in onCreateView after inflating your layout

How to choose a view group in my android app

I am developing an app and have successfully added a floating action button using the library shown here. The floating button displays well but when i navigate to another fragment through the navigation drawer the button still displays instead i want the button to only display in the activity i created it. I checked for those that had similar issues online and i saw comments...saying that i have to set the View by modifying this line of code found within the method show below.
ViewGroup root = (ViewGroup) activity.findViewById(android.R.id.content);
root.addView(button, params);
Please can tell me how to achieve this, thanks in advance.
Library Method
public FloatingActionButton create() {
final FloatingActionButton button = new FloatingActionButton(activity);
button.setFloatingActionButtonColor(this.color);
button.setFloatingActionButtonDrawable(this.drawable);
params.gravity = this.gravity;
ViewGroup root = (ViewGroup) activity.findViewById(android.R.id.content);
root.addView(button, params);
return button;
}

if you can access the FAB view using findViewById you can simply do:
button.setVisibility(VISIBILITY.GONE);
to hide it, that way you can set visibility back to visible when you go back to that activity.
or if you can access view called 'root' (or can access button via getActivity().findViewById for Fragments)
root.removeView(button);

Set the FloatingActionButton to be invisible by default in the XML file:
<ImageButton android:id="#+id/button" android:visibility="invisible"/>
and make it visible by using the following code in the required activity class:
button.setVisibility(View.VISIBLE);

Create a Custom ImageButton Class with FrameLayout and TextView

I am a newbie, so, any help is appreciated. I read a lot of posts here at StackOverflow and also I searched for my doubt in Google, but it's hard to find a good answer.
Here is what I am trying to do:
<FrameLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1">
<ImageButton
android:background="#layout/roundcorners"
android:id="#+id/hug"
android:scaleType="centerInside"
android:cropToPadding="false"
android:paddingLeft="5dp"
android:paddingRight="5dp"
android:paddingBottom="10dip"
android:layout_height="fill_parent"
android:layout_width="fill_parent"
android:src="#drawable/hug">
</ImageButton>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|center"
android:textColor="#000000"
android:textSize="15dip"
android:textStyle="bold"
android:paddingBottom="5dip"
android:clickable="true"
android:text="Hug">
</TextView>
</FrameLayout>
Above you guys can see the XML version of what I need.
The point is... I will have many of these FrameLayouts at run time. Every information to fill out the buttons will come from a database.
So, I need to create a Java Class where I can use a loop through all the registers from my database and instantiate a new FrameLayout Class (this class must have an ImageButton and a TextView as you can see from above XML) and just pass parameters, like this:
for (int i = 0; i < mArray.length; i++) {
button = new MyNewImageButton(name, src, text);
}
The above is just to simplify. What I mean is that I will pass parameters from my database when creating an Instance of this class that I am planning to create. Of course, every single button created will be added to the layout.
So... my question is: I know how to do this using XML, but I am REALLY having a hard time to create a class to do this.
Any thoughts? Any help is appreciated.
P.S.: Sorry if I made any mistake in my English, ok? I am a Brazilian. Someday my English will be flawless! Sorry if this question was already answered.
sorry to answer my own question to make another question. I tried to use the comments but there's a limitation in the number of characters, so, I am really sorry.
Hey guys and #blessenm. Well... I tried to use inflater and I came up with the following code:
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
// *******************************************
setContentView(R.layout.main);
//this is my main screen
//it's a linearlayout vertical orientation
ViewGroup parent = (ViewGroup) findViewById(R.id.tela_principal);
//these two new LinearLayouts will be one above the other,
//just like two lines
LinearLayout l1 = new LinearLayout(this);
LinearLayout l2 = new LinearLayout(this);
//inside of each linearlayout I set the orientation to horizontal
//so, everytime a picture is inflated from xml, it will fill in one
//linearlayout
l1.setOrientation(LinearLayout.HORIZONTAL);
l2.setOrientation(LinearLayout.HORIZONTAL);
//setting linearlayout parameters, so they fill the whole screen
l1.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));
l2.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));
//the first two inflated xml imagebuttons I add to LinearView1
view = LayoutInflater.from(getBaseContext()).inflate(R.layout.figurabotao,
l1, true);
view = LayoutInflater.from(getBaseContext()).inflate(R.layout.figurabotao,
l1, true);
//the next two inflated xml imagebuttons I add to LinearView2
view = LayoutInflater.from(getBaseContext()).inflate(R.layout.figurabotao,
l2, true);
view = LayoutInflater.from(getBaseContext()).inflate(R.layout.figurabotao,
l2, true);
//after the above, we should have a grid 2X2
//after linearlayouts are filled, I add them to the main screen
parent.addView(l1, new LinearLayout.LayoutParams(0, 0, 1));
parent.addView(l2, new LinearLayout.LayoutParams(0, 0, 1));
However this is not working. In the errorlog I get the following message:
"Unhandled event loop exception".
Any ideas about what I am doing wrong?
Thanks!

If you are just trying to create a view from the xml and add it to the layout. Just use the LayoutInflater.
Inside the activity use something like
FrameLayout frame = (FrameLayout)getLayoutInfalter.inflate(
R.id.YOUR_VIEW_XML,null);
layout.addView(frame);
If you are trying to create a class extend the frame layout or the the view. Create a constructor which takes your parameters and assign's the required values.
EDIT:
To Acess Elements Inside
If you have set id's to those element, you can access them by
TextView text = (TextView)frame.findViewById(R.id.yourtextview);
Or you can use the child index like
TextView text = (TextView)frame.getChildAt(0);

It sounds like you are looking for a way to create a view class that will be an ImageButton and a TextView wrapped with a FrameLayout.
In this case, you could look into creating your own View class. Probably a View class that extends FrameLayout. See this dev article for more information about how to create a custom view. http://developer.android.com/guide/topics/ui/custom-components.html
Specifically the "Compound Controls" section: http://developer.android.com/guide/topics/ui/custom-components.html#compound

Android overlay a view ontop of everything?

Can you overlay a view on top of everything in android?
In iPhone I would get the new view set its frame.origin to (0,0) and its width and height to the width and height of self.view. Adding it to self.view would then cause it to act as an overlay, covering the content behind (or if it had a transparent background then showing the view behind).
Is there a similar technique in android? I realise that the views are slightly different (there are three types (or more...) relativelayout, linearlayout and framelayout) but is there any way to just overlay a view on top of everything indiscriminately?

Simply use RelativeLayout or FrameLayout. The last child view will overlay everything else.
Android supports a pattern which Cocoa Touch SDK doesn't: Layout management.
Layout for iPhone means to position everything absolute (besides some strech factors). Layout in android means that children will be placed in relation to eachother.
Example (second EditText will completely cover the first one):
<FrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="#+id/root_view">
<EditText
android:layout_width="fill_parent"
android:id="#+id/editText1"
android:layout_height="fill_parent">
</EditText>
<EditText
android:layout_width="fill_parent"
android:id="#+id/editText2"
android:layout_height="fill_parent">
<requestFocus></requestFocus>
</EditText>
</FrameLayout>
FrameLayout is some kind of view stack. Made for special cases.
RelativeLayout is pretty powerful. You can define rules like View A has to align parent layout bottom, View B has to align A bottom to top, etc
Update based on comment
Usually you set the content with setContentView(R.layout.your_layout) in onCreate (it will inflate the layout for you). You can do that manually and call setContentView(inflatedView), there's no difference.
The view itself might be a single view (like TextView) or a complex layout hierarchy (nested layouts, since all layouts are views themselves).
After calling setContentView your activity knows what its content looks like and you can use (FrameLayout) findViewById(R.id.root_view) to retrieve any view int this hierarchy (General pattern (ClassOfTheViewWithThisId) findViewById(R.id.declared_id_of_view)).

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/root_view"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<LinearLayout
android:id = "#+id/Everything"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<!-- other actual layout stuff here EVERYTHING HERE -->
</LinearLayout>
<LinearLayout
android:id="#+id/overlay"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="right" >
</LinearLayout>
Now any view you add under LinearLayout with android:id = "#+id/overlay" will appear as overlay with gravity = right on Linear Layout with android:id="#+id/Everything"

You can use bringToFront:
View view=findViewById(R.id.btnStartGame);
view.bringToFront();

The best way is ViewOverlay , You can add any drawable as overlay to any view as its overlay since Android JellyBeanMR2(Api 18).
Add mMyDrawable to mMyView as its overlay:
mMyDrawable.setBounds(0, 0, mMyView.getMeasuredWidth(), mMyView.getMeasuredHeight())
mMyView.getOverlay().add(mMyDrawable)

I have just made a solution for it. I made a library for this to do that in a reusable way that's why you don't need to recode in your XML. Here is documentation on how to use it in Java and Kotlin. First, initialize it from an activity from where you want to show the overlay-
AppWaterMarkBuilder.doConfigure()
.setAppCompatActivity(MainActivity.this)
.setWatermarkProperty(R.layout.layout_water_mark)
.showWatermarkAfterConfig();
Then you can hide and show it from anywhere in your app -
/* For hiding the watermark*/
AppWaterMarkBuilder.hideWatermark()
/* For showing the watermark*/
AppWaterMarkBuilder.showWatermark()
Gif preview -

I have tried the awnsers before but this did not work.
Now I jsut used a LinearLayout instead of a TextureView, now it is working without any problem. Hope it helps some others who have the same problem. :)
view = (LinearLayout) findViewById(R.id.view); //this is initialized in the constructor
openWindowOnButtonClick();
public void openWindowOnButtonClick()
{
view.setAlpha((float)0.5);
FloatingActionButton fb = (FloatingActionButton) findViewById(R.id.floatingActionButton);
final InputMethodManager keyboard = (InputMethodManager) getSystemService(getBaseContext().INPUT_METHOD_SERVICE);
fb.setOnClickListener(new View.OnClickListener()
{
#Override
public void onClick(View v)
{
// check if the Overlay should be visible. If this value is false, it is not shown -> show it.
if(view.getVisibility() == View.INVISIBLE)
{
view.setVisibility(View.VISIBLE);
keyboard.toggleSoftInput(InputMethodManager.SHOW_IMPLICIT, 0);
Log.d("Overlay", "Klick");
}
else if(view.getVisibility() == View.VISIBLE)
{
view.setVisibility(View.INVISIBLE);
keyboard.toggleSoftInput(0, InputMethodManager.HIDE_IMPLICIT_ONLY);
}

bringToFront() is super easy for programmatic adjustments, as stated above. I had some trouble getting that to work with button z order because of stateListAnimator. If you end up needing to programmatically adjust view overlays, and those views happen to be buttons, make sure to set stateListAnimator to null in your xml layout file. stateListAnimator is android's under-the-hood process to adjust translationZ of buttons when they are clicked, so the button that is clicked ends up visible on top. This is not always what you want... for full Z order control, do this:

How to set background color of an Activity to white programmatically?

How can I set the background color of an Activity to white programatically?

Add this single line in your activity, after setContentView() call
getWindow().getDecorView().setBackgroundColor(Color.WHITE);

Get a handle to the root layout used, then set the background color on that. The root layout is whatever you called setContentView with.
setContentView(R.layout.main);
// Now get a handle to any View contained
// within the main layout you are using
View someView = findViewById(R.id.randomViewInMainLayout);
// Find the root view
View root = someView.getRootView();
// Set the color
root.setBackgroundColor(getResources().getColor(android.R.color.red));

I prefer coloring by theme
<style name="CustomTheme" parent="android:Theme.Light">
<item name="android:windowBackground">#color/custom_theme_color</item>
<item name="android:colorBackground">#color/custom_theme_color</item>
</style>

?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#FFFFFF"
android:id="#+id/myScreen"
</LinearLayout>
In other words, "android:background" is the tag in the XML you want to change.
If you need to dynamically update the background value, see the following:
Exercise: Change background color, by SeekBar

In your onCreate() method:
getWindow().getDecorView().setBackgroundColor(getResources().getColor(R.color.main_activity_background_color));
Also you need to add to values folder a new XML file called color.xml and Assign there a new color property:
color.xml:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<color name="main_activity_background_color">#000000</color>
</resources>
Note that you can name the color.xml any name you want but you refer to it by code as R.color.yourId.
EDIT
Because getResources().getColor() is deprecated, use getWindow().getDecorView().setBackgroundColor(ContextCompat.getColor(MainActivity.this, R.color.main_activity_background_color));
instead.

You can use this to call predefined android colours:
element.setBackgroundColor(android.R.color.red);
If you want to use one of your own custom colours, you can add your custom colour to strings.xml and then use the below to call it.
element.setBackgroundColor(R.color.mycolour);
However if you want to set the colour in your layout.xml you can modify and add the below to any element that accepts it.
android:background="#FFFFFF"

Button btn;
View root;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn = (Button)findViewById(R.id.button);
btn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
root =findViewById(R.id.activity_main).getRootView();
root.setBackgroundColor(Color.parseColor("#FFFFFF"));
}
});
}

To get the root view defined in your xml file, without action bar, you can use this:
View root = ((ViewGroup) findViewById(android.R.id.content)).getChildAt(0);
So, to change color to white:
root.setBackgroundResource(Color.WHITE);

View randview = new View(getBaseContext());
randview = (View)findViewById(R.id.container);
randview.setBackgroundColor(Color.BLUE);
worked for me. thank you.

final View rootView = findViewById(android.R.id.content);
rootView.setBackgroundResource(...);

for activity
findViewById(android.R.id.content).setBackgroundColor(color)

The best method right now is of course
getWindow().getDecorView().setBackgroundColor(ContextCompat.getColor(MainActivity.this, R.color.main_activity_background_color));
Please be aware though, if you have anything set as the background color in Designer, it will overwrite anything you try to set in your code.