Develop Reference

Round corner for BottomSheetDialogFragment Not working on API <21

I am using this solution to round corners of dialog in BottomSheetDialogFragment and it works fine with API 21 and higher
But in Api < 21 it removes the background and the rounded background goes away.
How to make the background rounded in API < 21?
If it is not possible to change the background, please help me change the background color instead.

Morteza I made the code which makes the BottomSheetDialog Fragment dialog round corner by the following code and I tested it in KitKat version mobile as well.
Bottom Sheet Dialog Class code
public class MyBottomSheetDialog extends BottomSheetDialogFragment {
String string;
static MyBottomSheetDialog newInstance(String string) {
MyBottomSheetDialog f = new MyBottomSheetDialog();
Bundle args = new Bundle();
args.putString("string", string);
f.setArguments(args);
return f;
}
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
string = getArguments().getString("string");
//bottom sheet round corners can be obtained but the while background appears to remove that we need to add this.
setStyle(DialogFragment.STYLE_NO_FRAME,0);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.bottom_sheet_modal, container, false);
TextView tv = (TextView) v.findViewById(R.id.text);
//dialog cancel when touches outside (Optional)
getDialog().setCanceledOnTouchOutside(true);
return v;
}}
bottom_sheet_modal.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/linearLayout"
android:orientation="vertical"
android:paddingBottom="10dp"
android:paddingLeft="10dp"
android:paddingRight="10dp"
android:paddingTop="10dp"
//adding background from drawable
android:background="#drawable/rounded_dialog">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:layout_gravity="center"
android:gravity="center"
android:weightSum="10"
android:layout_marginStart="20dp"
android:layout_marginEnd="20dp">
<Button
android:layout_width="0dp"
android:layout_weight="5"
android:layout_height="wrap_content"
android:text="Buy"
/>
<Button
android:layout_width="0dp"
android:layout_weight="5"
android:layout_height="wrap_content"
android:text="sell"
/>
</LinearLayout>
</LinearLayout>
rounded_dialog.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<solid android:color="#444343"/>
<corners android:topLeftRadius="16dp"
android:topRightRadius="16dp"/>
</shape>
MainActivity.java
public class MainActivity extends AppCompatActivity {
BottomSheetDialogFragment bottomSheetDialogFragment;
Button button;
LinearLayout linearLayout;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
bottomSheetDialogFragment = MyBottomSheetDialog.newInstance("Bottom Sheet Dialog");
button = findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
bottomSheetDialogFragment.show(getSupportFragmentManager(),bottomSheetDialogFragment.getTag());
}
});
}
}
Try this and let me know #Morteza. Happy coding.

Create a custom drawable rounded_dialog.xml:
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<solid android:color="#android:color/white"/>
<corners android:topLeftRadius="16dp"
android:topRightRadius="16dp"/>
</shape>
view!!.getViewTreeObserver().addOnGlobalLayoutListener(object : ViewTreeObserver.OnGlobalLayoutListener {
override fun onGlobalLayout() {
if (Build.VERSION.SDK_INT < 16) {
view!!.getViewTreeObserver().removeGlobalOnLayoutListener(this)
} else {
view!!.getViewTreeObserver().removeOnGlobalLayoutListener(this)
}
val dialog = dialog as BottomSheetDialog?
val bottomSheet =
dialog!!.findViewById<View>(com.google.android.material.R.id.design_bottom_sheet) as FrameLayout?
//Change background Image for all android versions below Api < 21
bottomSheet!!.setBackgroundResource(R.drawable.rounded_dialog)
}
})

The simplest and cleanest solution, that worked for me, was to put the following 3 lines in onViewCreated(View view, Bundle savedInstanceState) method of my fragment class:
#Override
public void onViewCreated(#NonNull View view, #Nullable Bundle savedInstanceState) {
View bottomSheet = (View) view.getParent();
bottomSheet.setBackgroundTintMode(PorterDuff.Mode.CLEAR);
bottomSheet.setBackgroundTintList(ColorStateList.valueOf(Color.TRANSPARENT));
bottomSheet.setBackgroundColor(Color.TRANSPARENT);
}
This will allow for your custom drawable with rounded corners to be properly shown once set as the background of the top level view of your fragment layout.
In essence this overrides the default BottomSheetFragment attributes regarding color, tintMode and tintList.
Using this, there is no need for messing with style resources.

Changing color of buttons with onclick events

I'm trying to create a Grid with 100 buttons, and a custom color selector. When i click a random button, it should change its' background into the selected color. Unfortunately I'm stuck on the following:
MainActivity:
I'm not sure how to automate the onclick event for every button seperately, as the onclick function doesn't recognise which button is clicked in the inner class.
I'm using a gridview with a custom adapter:
Adapter:
The adapter implemented in my Gridview --> linearlayout.pixel is the xml file for my button.
Code linearlayout.pixel:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="5dp" >
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text=""
android:background="#drawable/my_button"
android:id="#+id/grid_button"
/>
code drawable my_button:
<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle">
<corners android:radius="3dp" />
<stroke android:width="5px" android:color="#000000" />
Any suggestions are welcome!

Try this:
Button button = (Button)findViewById(R.id.grid_button);
button.setOnClickListener(new View.OnclickListener()
{
#Override
public void onClick(View view){
button.setBackgroundColor("#4FC3F7");
}
};

Try this:
buttons[i]=new Button(this);
buttons.setId(i);
buttons[i].setOnClickListener(new View.OnclickListener()
{
#Override
public void onClick(View view){
buttons[view.getId()].setBackgroundColor(color);
}
};

How to define color for selected TextViews once in Android?

I have a ListView and created a xml file for ListView items.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#drawable/list_item_selector_back"
android:minHeight="?attr/listPreferredItemHeight"
android:orientation="vertical">
<CheckedTextView
android:id="#+id/list_item_title"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:checkMark="?android:attr/listChoiceIndicatorMultiple"
android:textColor="#color/list_item_selector_fore" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal">
<TextView
android:id="#+id/list_item_author"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="#color/list_item_selector_fore" />
<!-- and many more TextView elements -->
</LinearLayout>
</LinearLayout>
list_item_selector_fore.xml:
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:color="#android:color/white" android:state_pressed="true" />
<item android:color="#android:color/white" android:state_activated="true" />
<item android:color="#android:color/white" android:state_focused="true" />
<item android:color="#android:color/black" />
</selector>
As you can see, I defined the background once in the root LinearLayout. But I had to set android:textColor="#color/list_item_selector_fore" for every TextView.
I tried it with foreground, but nothing happened. How can I get this smarter?
HOW TO LOOK:
two list view items

If you want do it for all TextView, the best way should be to subclass TextView
public class CustomeTextView extends TextView{
public CustomeTextView(Context context) {
super(context);
this.setTextColor(R.color.white);
}
}

If I understand the question correctly you want to change the colour of the text inside a TextView. From your XML it seems you want it to be onClick therefore you can do this:
TextView textView = (TextView) findViewById(R.id.myTextView);
textView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
textView.setTextColor('set text color here');
}
});
EDIT:
If you have these items inside of a ListView I would suggest that the easiest way for you to achieve what you want is to set an OnItemClickListenerand then change the textColor based on the OnItemClick event, which may look something like this;
ListView listView = (ListView) findViewById(R.id.listView);
listView.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
TextView textView = (TextView) view.findViewById(R.id.rowItemTextView);
textView.setTextColor('color goes here');
}
});
Hopefully this short snippet will guide you in the right direction to go.

Remove alert dialog border With Custom Theme

In my application i am using alert dialog with rounded rectangle theme.But it have alertdialog rectangle and my theme.My problem is how to replace alert dialog border like dialog.I want to show this set item with own theme only.
I want output this manner instead of the above theme:
Main Activity:
AlertDialog.Builder alertSeverity = new AlertDialog.Builder(
getActivity(), R.style.Theme_CustomDialog);
alertSeverity.setTitle("Severity Status");
CharSequence[] severityStatus = { "Low-Severity",
"Middle-Severity", "High-Severity" };
alertSeverity.setItems(severityStatus,
new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
}
});
My Theme:
<style name="Theme.CustomDialog" parent="android:style/Theme.Dialog">
<item name="android:windowBackground">#drawable/shapedialogtheme</item>
<item name="android:windowFrame">#null</item>
</style>
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" >
<solid android:color="#565656" />
<stroke
android:width="5dp"
android:color="#ffff8080" />
<corners android:radius="30dp" />
<padding
android:bottom="10dp"
android:left="10dp"
android:right="10dp"
android:top="10dp" />
<size
android:width="150dp"
android:height="150dp"/>
</shape>

Use Dialog instead of AlertDialog.
Create your custom layout which you want to show in dialog and setContent in dialog.
Apply this theme android.R.style.Theme_Translucent_NoTitleBar in dialog it will hide border.
Here is sample code.
Dialog dialog = new Dialog(activity.this, android.R.style.Theme_Translucent_NoTitleBar);
// your layout file
dialog.setContentView(R.layout.dialog);
// for hide title
dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
//for set title
dialog.setTitle("Custom Dialog");
dialog.show();
Updated:
just tried this in AlertDialog.
AlertDialog.Builder alertSeverity = new AlertDialog.Builder(
getActivity(), android.R.style.Theme_Translucent_NoTitleBar);

try the next solution:
extend from dialog, and set the exact view to use by using setContentView .
the alertDialog is used for some functionalities. it's not that it can do anything you want.
maybe instead of extending you could take the dialog and then use the setContentView.

Use Dialog instead of AlertDialog
Dialog callAlert = new Dialog(LoginActivity.this,R.style.CutomDialog);
callAlert.setContentView(R.layout.call);
Style.xml
<style name="CutomDialog" parent="android:style/Theme.Dialog">
<item name="android:windowBackground">#android:color/transparent</item>
<item name="android:windowNoTitle">true</item>
<item name="android:windowAnimationStyle">#style/Animations.DialogAnimation</item>
</style>
call.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_margin="20dp"
android:background="#drawable/call_bg"></RelativeLayout>
call_bg.xml
<shape xmlns:android="http://schemas.android.com/apk/res/android" >
<stroke android:width="3dp" android:color="#A20B3F" />
<corners android:bottomRightRadius="4dp" android:bottomLeftRadius="4dp"
android:topLeftRadius="4dp" android:topRightRadius="4dp"/>
Main thing is that you have to make layout backgrpund transparent otherwise you will not able to get output as you want.

You need to design a custom dialog for this purpose :
**dialog.xml**
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:id="#+id/txt_view_SaveAs"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/save_as"
android:layout_margin="10dp"
android:textSize="25dp" />
<EditText
android:id="#+id/edit_txt_SaveAs"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:minWidth="300dp"
android:maxLines="1"
android:textSize="20dp"
android:maxLength="50"
android:layout_margin="10dp"
android:text="#string/save_as" />
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:layout_margin="10dp"
android:weightSum="1.0" >
<Button
android:id="#+id/btn_SaveAs"
android:layout_width="0dp"
android:layout_height="50dp"
android:layout_weight="0.5"
android:minWidth="100dp"
android:textSize="20dp"
android:text="#string/save"
android:layout_margin="3dp" />
<Button
android:id="#+id/btn_Cancel"
android:layout_width="0dp"
android:layout_height="50dp"
android:layout_weight="0.5"
android:minWidth="100dp"
android:textSize="20dp"
android:text="#string/cancel"
android:layout_margin="3dp" />
</LinearLayout>
You can then make different class for the particular dialog like this:
public class SaveDialog extends Dialog implements android.view.View.OnClickListener {
private Context context;
private TextView txt_view_SaveAs;
private EditText edit_txt_SaveAs;
private Button btn_SaveAs;
private Button btn_Cancel;
public SaveDialog(Context context) {
super(context);
this.context = context;
// TODO Auto-generated constructor stub
}
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.dialog);
setCancelable(true); // Setting the Dialog to be Cancellable on Back Key Press
txt_view_SaveAs = (TextView) findViewById(R.id.txt_view_SaveAs);
edit_txt_SaveAs = (EditText) findViewById(R.id.edit_txt_SaveAs);
btn_SaveAs = (Button) findViewById(R.id.btn_SaveAs);
btn_SaveAs.setOnClickListener(this);
btn_Cancel = (Button) findViewById(R.id.btn_Cancel);
btn_Cancel.setOnClickListener(this);
}
#Override
public void onClick(View v) {
// Write code for all the buttons on click methods
}
}
Then you can call the custom dialog in your main class by using the following code :
SaveDialog save_dialog = new SaveDialog(saving_activity);
save_dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
save_dialog.show();

You can not remove border from alert dialog.
use this
public class ActivityIndicator extends Dialog implements android.view.View.OnClickListener{
protected static final String TAG = InfoIndicator.class.getName();
ImageView close;
WebView info;
public ActivityIndicator (Context context,String information)
{
super(context, android.R.style.Theme_Translucent_NoTitleBar);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.info);
setCancelable(true);
}
}
and try this below function for show, hide and clear dialog
private static ActivityIndicator activityIndicator;
public static void hideActivityViewer() {
if (activityIndicator != null) {
activityIndicator.dismiss();
}
activityIndicator = null;
}
public static void showActivityViewer(Context context) {
if (activityIndicator == null)
{
activityIndicator = new ActivityIndicator(context);
}
activityIndicator.show();
}
public static void clearDialogs()
{
activityIndicator = null;
}

you can use popwindow for more style by yourself

Android Dialog - Rounded Corners and Transparency

I'm trying to make a custom android dialog with rounded corners. My current attempts have given me this result.
As you can see, the corners are rounded, but it leaves the white corner still intact.
Below is the xml that I put in the drawable folder to create the blue dialog with the red border with the rounded corners.
<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
<item>
<shape
android:shape="rectangle">
<solid android:color="#color/transparent_black" />
<corners android:radius="#dimen/border_radius"/>
</shape>
</item>
<item
android:left="#dimen/border_width"
android:right="#dimen/border_width"
android:top="#dimen/border_width"
android:bottom="#dimen/border_width" >
<shape android:shape="rectangle">
<solid android:color="#color/blue" />
<corners android:radius="#dimen/border_radius"/>
</shape>
</item>
</layer-list>
Below is the layout of the dialog.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
style="#style/fill"
android:orientation="vertical"
android:layout_margin="#dimen/spacing_normal"
android:padding="#dimen/spacing_normal"
android:background="#drawable/border_error_dialog" >
<RelativeLayout
style="#style/block"
android:layout_gravity="center" >
<ImageView
android:id="#+id/imageView1"
style="#style/wrap"
android:layout_alignParentLeft="true"
android:layout_centerHorizontal="true"
android:contentDescription="#string/content_description_filler"
android:src="#drawable/ic_launcher" />
<TextView
android:id="#+id/textView1"
style="#style/error_text"
android:layout_centerVertical="true"
android:layout_toRightOf="#+id/imageView1"
android:text="#string/error_login" />
</RelativeLayout>
<Button
android:id="#+id/button1"
style="#style/wrap"
android:layout_gravity="center"
android:text="Button" />
</LinearLayout>
And below is the Activity in which I create the dialog.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button b1 = (Button) findViewById(R.id.button1);
b1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(MainActivity.this);
View child = getLayoutInflater().inflate(R.layout.dialog_custom_tom, null);
alertDialogBuilder.setView(child);
AlertDialog alertDialog = alertDialogBuilder.create();
alertDialog.show();
}
});
}

The only solution I have found is here. Use Dialog instead of AlertDialog and set transparent background:
dialog.getWindow().setBackgroundDrawableResource(android.R.color.transparent);
Therefore you can't use the builder. But you can use new Dialog() also in onCreateDialog callback of DialogFragment if you follow to best guidelines.
This works also for Gingerbread.
Besides the layered drawable can be simplified to one shape with xml element <stroke> for the border.

I had similar issue when made dialog extending DialogFragment and to fix this used:
dialog.setStyle(DialogFragment.STYLE_NO_FRAME, 0);
Like this:
public class ConfirmBDialog extends DialogFragment {
public static ConfirmBDialog newInstance() {
ConfirmBDialog dialog = new ConfirmBDialog();
Bundle bundle = new Bundle();
dialog.setArguments(bundle);
return dialog;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// This removes black background below corners.
setStyle(DialogFragment.STYLE_NO_FRAME, 0);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.confirm_dialog, container, true);
getDialog().setCanceledOnTouchOutside(true);
return view;
}
Hope this helps.

Just try
myDialog.getWindow().setBackgroundDrawable(new ColorDrawable(android.graphics.Color.TRANSPARENT));

The below code solved the issue
MyDialog mydialog = new MyDialog(this, "for testing",
new myOnClickListener() {
#Override
public void onPositiveButtonClick() {
// TODO Auto-generated method stub
Toast.makeText(getApplicationContext(),
"I am positive button in the dialog",
Toast.LENGTH_LONG).show();
}
#Override
public void onNegativeButtonClick() {
// TODO Auto-generated method stub
Toast.makeText(getApplicationContext(),
"I am negative button in the dialog",
Toast.LENGTH_LONG).show();
}
});
// this will remove rectangle frame around the Dialog
mydialog.getWindow().setBackgroundDrawableResource(android.R.color.transparent);
mydialog.show();
Thanks,
Nagendra

In you java file keep below code and change your layout name
View mView =LayoutInflater.from(mContext).inflate(R.layout.layout_pob,null);
alertDialog.getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));

just try using this, this worked for me
dialog.getWindow().setBackgroundDrawableResource(android.R.color.transparent);

Use 9-patch PNG with transparency in those corners.

public void initDialog() {
exitDialog = new Dialog(this);
exitDialog.getWindow().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));
View view = View.inflate(this, R.layout.dialoglayout, null);
exitDialog.setContentView(view);
AdSize adSize = new AdSize(300, 250);
dialogAdview = new AdView(this);
dialogAdview.setAdUnitId(getResources().getString(R.string.banner_id));
dialogAdview.setAdSize(adSize);
RelativeLayout adLayout = (RelativeLayout) view.findViewById(R.id.adLayout);
adLayout.addView(dialogAdview);
AdRequest adRequest = new AdRequest.Builder()
.build();
dialogAdview.loadAd(adRequest);
dialogAdview.setAdListener(new AdListener() {
#Override
public void onAdLoaded() {
Log.d("Tag", "adLoaded");
super.onAdLoaded();
}
});
view.findViewById(R.id.yes_btn).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
exit = true;
onBackPressed();
}
});
view.findViewById(R.id.no_btn).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
exit = false;
exitDialog.dismiss();
}
});
}
dialoglayout.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:ads="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#drawable/custom_dialog_round"
android:orientation="vertical">
<TextView
android:id="#+id/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginLeft="10dp"
android:text="Do you want to exit?"
android:textColor="#000"
android:textSize="18dp" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="#+id/text"
android:orientation="horizontal">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_weight="1"
android:gravity="center"
android:orientation="horizontal">
<TextView
android:id="#+id/yes_btn"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#drawable/background_draw"
android:padding="8dp"
android:text="Yes"
android:textAlignment="center"
android:textColor="#9fa8da"
android:textSize="20dp" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_weight="1"
android:gravity="center"
android:orientation="horizontal">
<TextView
android:id="#+id/no_btn"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="10dp"
android:background="#drawable/background_draw"
android:padding="8dp"
android:text="No"
android:textAlignment="center"
android:textColor="#d50000"
android:textSize="20dp" />
</LinearLayout>
</LinearLayout>
</LinearLayout>
`
custom_dialog_round.xml
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<solid
android:color="#fff"/>
<corners
android:radius="10dp" />
<padding
android:left="10dp"
android:top="10dp"
android:right="10dp"
android:bottom="10dp" />
</shape>
reference http://techamongus.blogspot.com/2018/02/android-create-round-corner-dialog.html

UPDATE
I understood that activity's background makes sense. So use #robert's answer with these changes.
in DialogFragment layout set width and height or add minimum sizes:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="wrap_content" // Or match_parent, 300dp.
android:layout_height="wrap_content"
android:layout_marginLeft="50dp"
android:layout_marginRight="50dp"
android:background="#drawable/white_round_corner_background"
android:gravity="center"
android:minWidth="300dp"
android:minHeight="200dp"
android:orientation="vertical"
android:padding="15dp"
>
...
Remove <item name="android:background">#color/...</item> from styles of needed activities and set these backgrounds in activity's layouts.
In DialogFragment write:
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// This removes black background below corners.
setStyle(DialogFragment.STYLE_NO_FRAME, 0);
}
Old variant
According to robert answer, you should apply setStyle(STYLE_NO_FRAME, 0), but there appear new problems. If you have a narrow DialogFragment like in Custom dialog too small, then you should follow this guide.
Add to styles.xml these 3 lines for dialog size:
<style name="ErrorDialogTheme" parent="#android:style/Theme.Dialog">
<item name="android:minWidth" type="dimen">300dp</item>
<!-- This option makes dialog fullscreen and adds black background, so I commented it -->
<!-- <item name="android:minHeight" type="dimen">200dp</item> -->
<!-- This option doesn't work, so I commented it -->
<!-- <item name="android:layout_width">match_parent</item> -->
</style>
In layout of your DialogFragment add style:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
...
android:minWidth="300dp" // Optional, remove this line.
android:minHeight="200dp" // Optional, remove this line.
style="#style/ErrorDialogTheme"
android:theme="#style/ErrorDialogTheme"
>
In code of your DialogFragment write:
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
// This removes black background. If not 0 as a parameter, black background will appear.
setStyle(STYLE_NO_FRAME, 0)
}
// If you want a fullscreen dialog, use this, but it doesn't remove a black background.
override fun onStart() {
super.onStart()
dialog.window?.setLayout(WindowManager.LayoutParams.MATCH_PARENT,
WindowManager.LayoutParams.MATCH_PARENT)
}
Look at AndroidManifest.xml and find all activities that can show these dialogs, check android:theme="..." themes and go to styles.xml. Now take a look at <item name="android:background">#color/...</item> items of these themes. There should be a transparent color or these items might not exist. If you have these background items, whole activities will have those backgrounds and dialogs too! So, if you have a camera activity with DialogFragment above it, you will see this.
Remove background items of needed styles. Also maybe background is set in code, check it.
In Dialog with transparent background in Android and many pages it is written to add one of these:
dialog.getWindow().setBackgroundDrawableResource(android.R.color.transparent);
dialog.getWindow().setBackgroundDrawable(new ColorDrawable(0));
dialog.getWindow().setBackgroundDrawable(new ColorDrawable(android.graphics.Color.TRANSPARENT));
probably in onViewCreated() or onCreateDialog(), but it didn't help me, because the background of the Activity was set in styles.
Tested on Samsung Galaxy S4 running Android 5.0.1.

Use CardView and make
app:cardCornerRadius="dp"
According shape xml.

I will post my solution here because it may be helpful. The solution that worked for me was to set the drawable resource in the layout xml and also in the activity that starts the dialog, without switching from AlertDialog to Dialog.
This would mean that in the layout where we create our design for the dialog alert_dialog_design.xml we will have the property android:background filled with our own defined background alert_dialog_shape.xml:
android:background="#drawable/alert_dialog_shape"
But also inside the activity that starts the dialog:
alert.getWindow().setBackgroundDrawableResource(R.drawable.alert_dialog_shape);
This way the parent (the alert itself) of your custom layout will have the shape you desire. Using this method I achieved the following:
https://i.stack.imgur.com/drCw3.png