[android] make number select dialog with DialogFragment

The DialogFragment class provides all the controls you need to create your dialog and manage its appearance, instead of calling methods on the Dialog object.

The DialogFragment class was originally added with Android 3.0 (API level 11), for older API this class is provided with the Support Library.

if use support library version & proguard,

-keep class android.support.v4.app.** { *; }
-keep interface android.support.v4.app.** { *; }

should be added to proguard rule.

Create NumberPickerDialogFragment

Override onCreateDialog() method.

the returned Dialog will be shown when NumberPickDialogFragment instance call show() method.

for example in Activiry
when click "Show Number Picker Dialog"

Create NumberPicker

set NumberPickDialogFragment view with NumberPicker
now Dialog will be shown like this

Create Interface
Selected value will be handled by Activity that made the Dialog, so declare interface to pass the value.
this interface called when "OK" & "Cancel" clicked.
implement in Activity

when Show Number Pick Dialog button clicked

When OK clicked show text 100

Complete code

MainActivity.java
NumberPcikDialogFragment.java