Android Studio bug versioncode versionname signed apk issue

Invalid proguard configuration file path
C:\documents\my_android_projects\my_project\proguard.cfg does not exist or is not a regular file

Solution:
Check if exist file proguard.cfg in your project on the path C:\docum.........
If not exist, copy a file proguard.cfg from other project or create file proguard.cfg and insert
this source code to file and save this file.

-optimizationpasses 5
-dontusemixedcaseclassnames
-dontskipnonpubliclibraryclasses
-dontpreverify
-verbose
-optimizations !code/simplification/arithmetic,!field/*,!class/merging/*

-keep public class * extends android.app.Activity
-keep public class * extends android.app.Application
-keep public class * extends android.app.Service
-keep public class * extends android.content.BroadcastReceiver
-keep public class * extends android.content.ContentProvider
-keep public class * extends android.app.backup.BackupAgentHelper
-keep public class * extends android.preference.Preference
-keep public class com.android.vending.licensing.ILicensingService

-keepclasseswithmembernames class * {
    native <methods>;
}

-keepclasseswithmembers class * {
    public <init>(android.content.Context, android.util.AttributeSet);
}

-keepclasseswithmembers class * {
    public <init>(android.content.Context, android.util.AttributeSet, int);
}

-keepclassmembers class * extends android.app.Activity {
   public void *(android.view.View);
}

-keepclassmembers enum * {
    public static **[] values();
    public static ** valueOf(java.lang.String);
}

-keep class * implements android.os.Parcelable {
  public static final android.os.Parcelable$Creator *;
}

From more details see:
//developer.android.com/guide/developing/tools/proguard.html

Open your workspace folder and subfolder .metadata:
C:\Users\workspace\.metadata\

Delete .lock file

Try this solution - into xml file add row to EditText tag:

android:textColorHint="@color/grey"

break statement in Java Android basic example

MainClass.java

public class MainClass {
	public static void main(String[] arg) {
		String[] arrayOfString = {"nothing", "Hello", "people"
				, "bye-bye", "hello", "world!", "end" };
		
		for (int i = 0; i < arrayOfString.length; i++) {
				System.out.println(arrayOfString[i]);
				if(i > 2) 
					break; // end of loop
		}
	}
}
/*
nothing
Hello
people
bye-bye
*/

Click to Android version combobox - drop down menu and select your version, which just using (have instaled). For example: You updated ADT by SDK manager, but forget to update Android version. You can use lower version from drop down menu, which using your project, or do update of Android by SDK manager.