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Show custom progress bar in Android Studio

I know this is common to ask, but yet I still don't know how to call the XML file. I'm just confused about how can I implement the proper calling progress bar when going to another activity. Yet there are lots of resources on site but I think this is different. All I want is When I click the button from first Activity I want to call the progress bar which separately designs as XML and then it goes to the second activity, whether it will set Visible etc. It is possible?
Reference spinKit: Github
When clicking the button in first activity it will pop the spin XML and then dismiss when second activity is already loaded.
MainActivity
import androidx.appcompat.app.AppCompatActivity;
public class MainActivity extends AppCompatActivity {
Button clickButton;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
clickButton =(Button) findViewById(R.id.buttons);
clickButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, Activity2.class);
startActivity(intent);
}
});
}
}
ActivityMain
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<Button
android:id="#+id/buttons"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:hint="Click"
android:textSize="10dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
android:textColor="#color/white"/>
</androidx.constraintlayout.widget.ConstraintLayout>
Spinkit class
import androidx.appcompat.app.AppCompatActivity;
public class Spinkit extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.loadingspin);
ProgressBar progressBar = (ProgressBar)findViewById(R.id.spin_kit);
Sprite cubeGrid = new CubeGrid();
progressBar.setIndeterminateDrawable(cubeGrid);
}
}
Spinkit 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"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:background="#color/orange"
android:gravity="center"
android:orientation="vertical">
<com.github.ybq.android.spinkit.SpinKitView
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/spin_kit"
style="#style/SpinKitView.Large.CubeGrid"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
app:SpinKit_Color="#color/white"
tools:ignore="MissingConstraints" />
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="LOADING"
android:textStyle="bold"
android:textSize="40sp"
android:gravity="center"
android:shadowColor="#color/black"
android:textColor="#color/white"/>
</LinearLayout>

Actually you have two activity. And now you want to show animation when changing activity. A professional Android App Developer chooses to use fragment since fragment makes thing easier. Since you are using activity hence I will include information of activity.
You directly can't show that animation. You must add an activity (you can directly code even if you want you can use layout either whatever you prefer).
Someone had mentioned in the comment that "it takes milisec to change activity". But if you want to delay than you can do that.
At first create an activity as another person said. Design it however you want. Then use the following code to change activity.
In MainActivity :
Intent intent = new Intent(this, SplashScreenActivity.class);
startActivity(intent);
//If you don't want user to back to the page by clicking back button then use finish();
finish();
In SplashScreenActivity :
//Use SpinKit however they have introduced https://github.com/ybq/Android-SpinKit#usage
ProgressBar progressBar = (ProgressBar)findViewById(R.id.progress);
Sprite doubleBounce = new DoubleBounce();
progressBar.setIndeterminateDrawable(doubleBounce);
new Handler().postDelayed(() ->{
Intent intent = new Intent(SplashActivity.this,HomeActivity.class);
startActivity(intent);
},1000);
//1000 is millisecond if you want to delay 10 sec than write 10000 instead of 1000
Here's a related git repo
If you want to call SplashScreen while changing every single page than just a data with intent.
In your activity :
Intent intent = new Intent(this,SplashScreenActivity.class);
intent.putExtra("data","home");
startActivity(intent);
In SplashScreenActivity :
//write it in global variable
Sprite doubleBounce = new DoubleBounce();
ProgressBar progressBar;
//onCreate method
progressBar = (ProgressBar)findViewById(R.id.progress);
Intent intent = getIntent();
String activity = intent.getStringExtra("data");
if(activity.equals("home")){
changeActivity(homeActivity.class);
}else if(activity.equals("secondActivity")){
changeActivity(secondActivity.class);
}
//Another class
private void changeActivity(Class activity){
progressBar.setIndeterminateDrawable(doubleBounce);
new Handler().postDelayed(() ->{
Intent intent = new Intent(this,activity);
startActivity(intent);
},1000);
}

This is how you can do it.
Create another activity named anything you want for loading.Eg - LoadingActivity
Make a layout file looking like this or however you want.
Then in the java class add this code in the onCreate
ProgressBar progressBar = (ProgressBar)findViewById(R.id.spin_kit);
Sprite cubeGrid = new CubeGrid();
progressBar.setIndeterminateDrawable(cubeGrid);
new Handler().postDelayed(new Runnable() {
#Override
public void run() {
startActivity(new Intent(this,OtherActivity.class));
finish();
}
Done!

Android Studio My Button on the second Activity doesn't Work

I think it a very easy Question. I am new to Android Studio and I could not find an answer.
I have an activity that switches per Button to another activity. However, on my second activity, my simple Button just to change the Textview which doesn't work.
Layout
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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="match_parent"
android:layout_height="match_parent"
tools:context=".StartActivity">
<TextView
android:id="#+id/twText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="127dp"
android:layout_marginLeft="127dp"
android:layout_marginTop="88dp"
android:layout_marginEnd="127dp"
android:layout_marginRight="127dp"
android:layout_marginBottom="624dp"
android:text="Ihr Passwort war Richtig!"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<Button
android:id="#+id/btnChecke"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="134dp"
android:layout_marginLeft="134dp"
android:layout_marginTop="32dp"
android:layout_marginEnd="189dp"
android:layout_marginRight="189dp"
android:layout_marginBottom="371dp"
android:text="Check"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
/>
</androidx.constraintlayout.widget.ConstraintLayout>
onCreate method in my second activity
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_start);
tw = findViewById(R.id.twText);
btnCheck = findViewById(R.id.btnChecke);
btnCheck.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
tw.setText("work");
}
});
}
And this is how I am starting the second activity (onCreate method from my first activity).
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_start);
tw = findViewById(R.id.twText);
Button btnCheck = findViewById(R.id.btnChecke);
btnCheck.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
setContentView("Work"R.layout.activity_main);
}
});
}
I have checked the variable names in the layout and looks like everything is fine.
Thank you in advance.

This answer is based on the problem which I found before the latest edit from the OP. Here is the version of the edit where I found the problem.
First of all, something is very wrong about the onClickListener of your button. You are setting the content view again, instead of starting your second activity. It looks like, you are just setting the content view of your StartActivity which actually does not launch the MainActivity that you are trying to start.
In order to start a new activity, you need to add the following in your button onClickListener.
btnCheck.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// setContentView(R.layout.activity_main); // This is not the way for starting another activity
Intent intent = new Intent(this, MainActivity.class);
startActivity(intent);
}
});
Once your MainActivity has started, you should be able to change the text with no problem.

Bundle bundle = getIntent().getExtras()
if(bundle.getString("changeTextView")
TextView .... = (TextView) ....setText();
Hi. If I good understand, you should use Intent with "putExtra()".
Exmple:intent.putExtras("changeTextView");
After that in your onCreate() method you can put:

How to Implement a method inside Activity class

I'm just starting to learn Android programming with Android Studio and unfortunately, but I have a big problem with probably a very simple thing, namely in the layout file of the main activity, I assigned the startActivity() method to the android:onClick property of the both buttons (android:onClick="startActivity()").
And now I should in the MainActivity class, implement startActivity() method but.... I do not know how to do it.
I saw that I should have in MainActivity: public void startActivity(View v). I tried and I was looking for solutions for a few hours and I already lost hope.
Especially that I can implement e.g. View.OnClickListener but methods, startActivity() can not do anymore. How could I implement this method?
I assigned the startActivity() method to the android:onClick property of the both buttons in activity_main.xml:
<Button
android:id="#+id/button"
android:onClick="startActivity()"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="32dp"
android:layout_marginTop="24dp"
android:text="#string/button"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
tools:ignore="OnClick" />
<Button
android:id="#+id/button2"
android:onClick="startActivity()"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="32dp"
android:layout_marginTop="16dp"
android:text="#string/button2"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/button"
tools:ignore="OnClick" />
Next i should in the MainActivity class, implement startActivity() method but.... I do not know how to do it :
public class MainActivity extends AppCompatActivity implements startActivity() {
Button b1, b2;
EditText et1, et2;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
b1 = findViewById(R.id.button);
b2 = findViewById(R.id.button2);
et1 = findViewById(R.id.editText);
et2 = findViewById(R.id.editText2);
public void startActivity(View v) {
if (v.getId() == R.id.button) {
String name = et1.getText().toString();
int age = Integer.parseInt(et2.getText().toString());
Intent i = new Intent(this, ResultActivity.class);
i.putExtra("name", name);
i.putExtra("age", age);
startActivity(i);
} else {
Intent i = new Intent(Intent.ACTION_VIEW,
Uri.parse("http://www.google.pl/"));
startActivity(i); }
}
}

You're incorrectly using onClick attribute. This is wrong:
android:onClick="startActivity()"
it should be:
android:onClick="startActivity"
Read more at https://developer.android.com/guide/topics/ui/controls/button#HandlingEvents
Suggestion
You should avoid using android:onClick in your xml. Use the onClickListener instead. It's important to separate your logic and UI layout so you don't need to think too much whenever your xml layout is changed. Use something like this:
Button button = (Button) findViewById(R.id.your_button);
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// Do something here when button is clicked.
}
});

As mentioned by ישו אוהב אותך9A
https://developer.android.com/guide/topics/ui/controls/button#HandlingEvents
Responding to Click Events
<Button xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/button_send"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/button_send"
//onClick function/method name don't use round brackets
android:onClick="sendMessage" />
and in your activity
//JAVA
/** Called when the user touches the button */
public void sendMessage(View view) {
// Do something in response to button click
}
//Kotlin
/** Called when the user touches the button */
fun sendMessage(view: View) {
// Do something in response to button click
}
and remove the tools:ignore="OnClick"
i hope it helps

Firstly, change this
android:onClick="startActivity()"
to this:
android:onClick="startActivity"
Then move your startActivity method below OnCreate method. It is currently inside OnCreate

How do i create a button to another page for my app

i was just wondering how i would make a button on my page so that it would go to another page for my app. I am a beginner so if you could explain how it all works and where it goes it would help a lot.
PS i am using android studio if that makes a difference and this is the code i have so far in my fragment_main.xml. I have not entered any code into the .java
<TextView android:text="#string/hello_world"
android:id="#id/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<ImageButton
android:id="#+id/firstbutton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#drawable/homebutton"
android:layout_below="#+id/text"/>

You can declare views and objects dynamically in Java, and then pass the button from fragment to fragment (or Activity to Activity, depending on your app).
To declare a Relative Layout with a Button, for example:
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Button;
import android.widget.RelativeLayout;
public class JavaLayoutActivity extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Button myButton = new Button(this);
RelativeLayout myLayout = new RelativeLayout(this);
myLayout.addView(myButton);
setContentView(myLayout);
}
This doesn't set the properties or anything, I am just using this as proof of concept.
XML makes things easy with regards to user interface design because you don't have to manage it in code, but this is one case where it is an exception. If you want dynamic interface objects, you need to use Java.

Instead of creating view dynamically you should obtain your view in activity
ImageButton button = (ImageButton) findViewById(R.id.firstButton)
and assign an onClick listener to id
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// start new Activity here
}
});
You can also do it in xml:
<ImageButton
android:id="#+id/firstbutton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#drawable/homebutton"
android:onClick="sendMessage"
android:layout_below="#+id/text"/>
with such configuration, you should add method in activity:
public void sendMessage(View view) {
// start another activity here
}

There are two methods available in android using which you can go from one Activity to another.
1. Use button.setOnClickListener()
Create a button in xml file.
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button" />
Now set event listener for the button in your .class file
Button button = (Button) findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
//set the event you want to perform when button is clicked
//you can go to another activity in your app by creating Intent
Intent intent = new Intent(getApplicationContext, Activity2.class);
startActivity(intent);
}
});
2. Use <android:onClick="goNext">
Put the onClick as the attribute of the button you have created in xml file.
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button"
android:onClick="goNext" />
Now in your .class file define an event for that button as,
goNext() {
Intent intent = new Intent(getApplicationContext, Activity2.class);
startActivity(intent);
}

Null pointer Exception at Onclicklistener in android

How to recover the problem of Null pointer exception in the place of menu.setOnClickListener(new View.OnClickListener() {
,
i have an imageview(menu) if i press on that another activity(about page) should get opened, but here on OnClick of imageview, i'm getting above error and app gets force close.
Here's the code
public class About extends Activity {
LinearLayout line1, line2;
ImageView menu;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_about);
menu = (ImageView)findViewById(R.id.menu);
menu.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
menu.setVisibility(View.VISIBLE);
// TODO Auto-generated method stub
line1.setVisibility(View.VISIBLE);
if (line2.getVisibility() == View.INVISIBLE || line2.getVisibility() == View.GONE) {
line2.setVisibility(View.VISIBLE); }
else {
line2.setVisibility(View.INVISIBLE);
}
}
});
ImageView about = (ImageView) findViewById(R.id.about);
about.setOnClickListener(new View.OnClickListener() {
public void onClick(View v){
startActivity(new Intent(About.this, About.class));
}
});
xml file
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#color/black" >
<LinearLayout
android:id="#+id/ll1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#color/black"
android:layout_alignParentTop="true"
android:layout_alignParentRight="true">
<ImageView
android:id="#+id/menu"
android:layout_width="50dp"
android:layout_height="50dp"
android:src="#drawable/menu" />
</LinearLayout>
<LinearLayout
android:id="#+id/ll2"
android:layout_width="199dp"
android:layout_height="wrap_content"
android:background="#color/black"
android:layout_toRightOf="#+id/ll1"
android:visibility="gone"
>
<ImageView
android:id="#+id/about"
android:layout_width="50dp"
android:layout_height="50dp"
android:layout_above="#+id/textView1"
android:layout_toLeftOf="#+id/jobs"
android:src="#drawable/about" />
</LinearLayout>
<TextView
android:id="#+id/textView3"
android:layout_width="match_parent"
android:layout_height="50dip"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:background="#color/white"
android:textColor="#color/white"/>

you are getting NullPointerException because you didn't have initialize imageview.please do it first.
ImageView menu=(ImageView)findViewById(R.id.menu);
write this line before you set onClick Listener to your image view and you are done.hope it will help.

As I suspected, you have declared menu as an instance variable (at the top of your class), but you never instantiate it as a local variable. Add the line
menu = (ImageView)findViewById(R.id.menu)
at the top of your onCreate() method, BEFORE you set the OnClickListener, and it will work.
There is a difference between declaring the instance variable (which you have done) and actually initializing it. In this sense, you can look at the onCreate() method like a constructor in a regular java class. It's not enough to declare the variable at the top of the class, you have to initialize it as a variable of the actual object.
This might sound trivial, but believe me it's not. When I was first learning java, before I wrapped my head around this concept, I spent many hours screaming at the screen over the same sorts of errors you're having now.

You've not properly initialized the menu variable before setting listener you should
menu = (ImageView)findViewById(id.menu);
then write your listen line....

You should pass the context of the activity which is running not the activity that you desire to run,the Problem is About.this , Replace it with the context of current Activity
startActivity(new Intent(About.this, About.class));

you have not Instantiate menu 1st instantiate.
You are calling the same class with in the same activity change your following code as following
startActivity(new Intent(About.this, About.class));
to
startActivity(new Intent(getApplicationContext(), NewClass.class));
or
startActivity(new Intent(CurrentClass.this, NewClass.class));

I had a similar issue. I found the xml id I'd used in findViewById() came from a different page layout than the one active at the time.
No warnings. Just need to make sure common buttons like Save have a good naming convention.