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App is crashing when I click the button - two intents in a button - using Enum

I need help with my code. Let me try to explain the problem:
At the first activity I have two fields where I'll set values from an Enum, for this I made a button for each field that basically shows me another activity, calls the value and brings it to the main activity. Still in the first activity I have a button that starts another activity and (at the same time) take all the values from the enum end sends to another activity. The point is, everything is working, but this last button no, when I click it the app crashes. What is happening and how can I solve it?
Here goes the code of the first activity:
public class MenuInicial extends AppCompatActivity {
public static final int CONSTANTE_BANZO = 1;
Button escolherM;
Button escolherB;
Button next;
TextView campoM;
TextView campoB;
Intent intent1;
Intent intent2;
Intent intentBundle;
Intent intentNext;
Bundle bundle;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_menu_inicial);
intent1 = new Intent(MenuInicial.this, Montante.class);
campoM = (TextView) findViewById(R.id.fieldM);
escolherM = (Button) findViewById(R.id.chooseM);
String perfilM = getIntent().getExtras().getString("nameM");
campoM.setText(perfilM);
escolherM.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v){
startActivity(intent1);
}
});
intent2 = new Intent(MenuInicial.this, Banzo.class);
campoB = (TextView) findViewById(R.id.fieldB);
escolherB = (Button) findViewById(R.id.chooseB);
escolherB.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v){
startActivityForResult(intent2, CONSTANTE_BANZO);
}
});
next = (Button) findViewById(R.id.prosseguir);
intentBundle = new Intent(MenuInicial.this, ConferenciaDosDados.class);
intentNext = new Intent(MenuInicial.this, Dados.class);
next.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String perfilM = getIntent().getExtras().getString("nameM");
Float baseMt = getIntent().getExtras().getFloat("baseM");
Float alturaMt = getIntent().getExtras().getFloat("alturaM");
String perfilB = getIntent().getExtras().getString("nameB");
Float baseBz = getIntent().getExtras().getFloat("baseB");
Float alturaBz = getIntent().getExtras().getFloat("alturaB");
bundle.putString("nomeM",perfilM);
bundle.putFloat("baseM",baseMt);
bundle.putFloat("alturaM",alturaMt);
bundle.putString("nomeB",perfilB);
bundle.putFloat("baseB",baseBz);
bundle.putFloat("alturaB",alturaBz);
intentBundle.putExtras(bundle);
startActivity(intentBundle);
startActivity(intentNext);
}
});
}
protected void onActivityResult(int codigo, int resultado, Intent intent){
if(codigo == CONSTANTE_BANZO){
Bundle bundleB = intent.getExtras();
if(bundleB != null){
String perfilB = bundleB.getString("nameB");
campoB.setText(perfilB);
}
}
}
}

next = (Button) findViewById(R.id.prosseguir);
intentBundle = new Intent(MenuInicial.this, ConferenciaDosDados.class);
intentNext = new Intent(MenuInicial.this, Dados.class);
next.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String perfilM = getIntent().getExtras().getString("nameM");
Float baseMt = getIntent().getExtras().getFloat("baseM");
Float alturaMt = getIntent().getExtras().getFloat("alturaM");
String perfilB = getIntent().getExtras().getString("nameB");
Float baseBz = getIntent().getExtras().getFloat("baseB");
Float alturaBz = getIntent().getExtras().getFloat("alturaB");
bundle.putString("nomeM",perfilM);
bundle.putFloat("baseM",baseMt);
bundle.putFloat("alturaM",alturaMt);
bundle.putString("nomeB",perfilB);
bundle.putFloat("baseB",baseBz);
bundle.putFloat("alturaB",alturaBz);
intentBundle.putExtras(bundle);
startActivity(intentBundle);
startActivity(intentNext);
}
});
Which activity do you want to go to? choose one. When you do, you can get those extras then when you need to goto the other activity, you can put those extras there too.
A better way to do it is to create a model (constructor with setters and getters) and put these in a list. At that point you can loop through the list and take what you need. It all depends on what you are doing though as the list will not be instantiated like intent extras would be.
Or, you can use SharedPref which is similar to a HashMap (which is also similar to the Intent Extras). SharedPref will store the key and value on the phones cache and then you can pull from that when you need it. Again, keep in mind that if the user clears the cache on the app, then it'll delete those shared pref.
Finally, you can also use a database such as Parse Server or Firebase.

Understanding and fixing instance handling between classes

Im having issues with the app crashing with nullpoint exception.
I know that it crashes when trying to get an ArrayList from pictureTalkFragment. which in this class is only set to PictureTalkFragment ptf;
In other words im trying to get an element (have both getter/setter for the arraylist in ptf, and made the arraylist public as an alternative) from an class and not the instance of that class.
But im just to noob to figure out how to correctly handle getting the instances between classes (activity ---> fragments and back etc). In Java i usually just had an referance in the Constructor that sent the instance/referance with the creation of the new class. But in Android theres all this onCreate (getActivity,getContext ++), Im confused:P When to user where and how:(
the EditPicture was started from this code in GridViewAdapter that extended from PictureTalkFragment (edit in onlongclicklistener)
row.setOnLongClickListener(new View.OnLongClickListener()
{
#Override
public boolean onLongClick(View v) {
PopupMenu popMenu = new PopupMenu(v.getContext(), v);
popMenu.getMenuInflater().inflate(R.menu.picturetalk_popup_menu, popMenu.getMenu());
popMenu.setOnMenuItemClickListener(new PopupMenu.OnMenuItemClickListener() {
#Override
public boolean onMenuItemClick(MenuItem menuItem) {
switch (menuItem.getItemId()) {
case R.id.edit:
Intent intent = new Intent(getContext(), EditPicture.class);
intent.putExtra("itemUUID", item.getId());
String s = new String("");
context.startActivity(intent);
break;
case R.id.remove:
FileInteraction fileInteraction = new FileInteraction();
fileInteraction.deleteFilesAndFolder(item.getImagePath());
item.setTitle("");
notifyDataSetChanged();
break;
default:
//
}
return true;
}
});
popMenu.show();
return true;
}
});
return row;
EditPicture class
public class EditPicture extends Activity {
private EditText text;
private Button applyBtn;
private ArrayList<PictureItem> piArray;
private PictureItem pi;
private UUID itemID;
private PictureTalkFragment ptf;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
itemID = (UUID) getIntent().getSerializableExtra("itemUUID");
SetLocalArray(ptf.getArray()); //Nullpoint here, and i know why. But not how to get the allready created instance of this class
getPictureItem();
setContentView(R.layout.picturetalk_edit_pic);
text = (EditText) findViewById(R.id.editName);
text.setText(pi.getTitle());
applyBtn = (Button) findViewById(R.id.applyChangeBtn);
applyBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
updatePictureItem();
ptf.setArray(piArray);
}
});
}
private void updatePictureItem() {
pi.setTitle(text.toString());
piArray.add(pi);
ptf.setArray(piArray);
}
private void SetLocalArray(ArrayList<PictureItem> array) {
this.piArray = array;
}
private PictureItem getPictureItem() {
pi = new PictureItem("", "");
for (int i = 0; i < piArray.size(); i++) {
if (itemID.equals(piArray.get(i))) {
pi = piArray.get(i);
piArray.remove(i);
}
}
return pi;
}}

I don't know what you are using the array for.
Usually you should not depend on the fragment to get the info, if you want to pass an array of objects to the activity, you should use the Bundle in the activity extras to do so, instead of passing only the UUID, just pass also the array you need.
If you want the lazy option just make a class with a static variable to store the fragment and use it in the activity, which I don't advise.

Android Passing values from one activity to other activity (string) or from one class to another

I have two class Profile.class and Details.class,
In profile class i have used a spinner with values like (ATM,Banking,Personal,Others etc)
and a button (OK).
on clicking ok button it will go to next activity that is details activity where i will be taking some details like-name,description etc.
after filling the details i have given a button (save).
on clicking button save i will be saving the name and description in database but i want to save the profile name also along with details. i am unable to transfer selected spinner text from Profile.class to Details.class
how to transfer?
create.class code
public class Create extends Activity {
public ArrayList<String> array_spinner;
Button button4;
String spinnertext;
/** Called when the activity is first created. */
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.create);
Spinner spinner = (Spinner) findViewById(R.id.spinner1);
array_spinner=new ArrayList<String>();
array_spinner.add("ATM");
array_spinner.add("Bank");
array_spinner.add("Mail");
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,android.R.layout.simple_spinner_item, array_spinner);
adapter.setNotifyOnChange(true);
spinner.setAdapter(adapter);
spinner.setLongClickable(true);
spinner.setOnLongClickListener(new OnLongClickListener(){
public boolean onLongClick(View v) {
// TODO Auto-generated method stub
return false;
}}
);
button4 = (Button)findViewById(R.id.button4);
button4.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
Intent myIntent4 = new Intent(view.getContext(), Details.class);
startActivityForResult(myIntent4, 0);
myIntent4 .putExtra("key", array_spinner.getSelectedItem().toString());
startActivity(myIntent4);
}
});
}}
details.class code
public class Details extends Activity {
EditText editText4,editText5,editText6;
Button button8,button9,button10;
TextView textView7;
String et4,et5,et6;
//SQLite Database db;
/** Called when the activity is first created. */
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.details);
String spinnervalue = getIntent().getExtras().getString("Key");
please kindly explain me what is this "key"?

You can use :
Intent i = new Intent(MainActivity.this,SecondActivity.class);
i.putExtra("YourValueKey", yourData.getText().toString());
then you can get it from your second activity by :
Intent intent = getIntent();
String YourtransferredData = intent.getExtras().getString("YourValueKey");
example
this is what you have to write in your first activity
Intent i = new Intent(getApplicationContext(), Product.class);
i.putExtra("productname", ori);
i.putExtra("productcost", position);
i.startActivityForResult(i,0);
then in your next activity you need to have this code
String productname,productcost;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.product);
tv1= (TextView)findViewById(R.id.tv1);
tv2= (TextView)findViewById(R.id.tv2);
Bundle extras= getIntent().getExtras();
if(extras!=null)
{
position = extras.getString("position"); // get the value based on the key
tv1.setText(productname);//use where ever you want
productname = extras.getString("productname"); // get the value based on the key
tv2.setText(productname);
}

First of all take a spinner and provide value to them what you want and then the selected spinner value change it to string value and this string variable will be used in OK button to pass value through use of Intent or Shared preference to take this value to another activity and through there you can use it in database to display this value.

If you want to send data to another activity, you can do it using intent.
Bundle bund = new Bundle();
bund.putString("myKey",name);
Intent intent = new Intent(Profile.this, Detail.class);
intent.putExtras(bund);
startActivity(intent);
Now in Detail class, receive this data in onCreate()
#Override
protected void onCreate(Bundle savedInstanceState) {
.......
String nameReceived = getIntent().getExtras().getString("myKey");
}
I have given the example of passing String to another activity however, you can pass boolean, int, double etc to another activity. See the full list on here

How Can I Pass Value Of Edittext From One Activity To Other in Android?

I want to pass the value of an EditText in one activity to another activity on button press and use that value in my code. However, there is one more activity between those activities in which I don't want to use that value
My Activity1 has:
textOut = (EditText)findViewById(R.id.ipadd);
Button ip = (Button) findViewById(R.id.ipad);
ip.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
startActivity(new Intent("com.shaz.hello"));
}});
From the Activity1 the user goes to the Activity2
Activity2
if ( x ==10 ) {
startActivity(new Intent("com.shaz.hello2"));
}
From the Activity2 the user goes to the Activity3
Activity3
Here I want to use that value as a String.

this is an another solution;
create one Bean class like this,
public class Bean {
public static String value;
public static String getValue() {
return value;
}
public static void setValue(String value) {
Bean.value = value;
}
}
On first Activity set the variable in Bean.
Bean bean = new Bean();
bean.setValue("your value");
And get the variable value on last or any Activity
Bean bean = new Bean();
String yourValue=bean.getValue();

You can using putExtra() and getExtra(), Add this in your current activity:
ip.setOnClickListener(new View.OnClickListener()
{
#Override
public void onClick(View v)
{
Intent mIntent = new Intent(currentActivity.this, hello.class);
mIntent.putExtra("valuename", Integer.valueOf(textOut.getText.toString));
startActivity(mIntent);
}
}
To get result from last activity put this line after onCreate():
int myValue = getIntent().getIntExtra("valuename", 0);
if (myValue == 10)
{
Intent mIntent = new Intent(currentActivity.this, hello2.class);
startActivity(mIntent);
}
Edited
You need to add your activities in android manifest file, e.g:
<activity android:name=".hello2"></activity>

How to pass values statically from one page to other in android?

In my projects I kept different images for categories. When I click on each category image I am passing its category id to other page statically and setting the drawable image of that category in the new page.
My Code:
Firstpage.java
public static String categoryid;
category1.setOnClickListener(new View.OnClickListener()
{
public void onClick(View view)
{
categoryid="0";
Intent myIntent = new Intent(view.getContext(),Nextpage.class);
startActivityForResult(myIntent, 0);
}
});
category2.setOnClickListener(new View.OnClickListener()
{
public void onClick(View view)
{
categoryid="1";
Intent myIntent = new Intent(view.getContext(),Nextpage.class);
startActivityForResult(myIntent, 0);
}
});
category3.setOnClickListener(new View.OnClickListener()
{
public void onClick(View view)
{
categoryid="2";
Intent myIntent = new Intent(view.getContext(),Nextpage.class);
startActivityForResult(myIntent, 0);
}
});
Nextpage.java
public static String catid = Firstpage.categoryid;
ImageView categorytype=(ImageView)findViewById(R.id.imageView1);
if(catid=="0")
{
categorytype.setBackgroundResource(R.drawable.image1);
}
else if(catid=="1")
{
categorytype.setBackgroundResource(R.drawable.image2);
}
else if(catid=="2")
{
categorytype.setBackgroundResource(R.drawable.image3);
}
First time when I am clicking on the category image it is passing the category id to the next page and that particular image is setting in the nextpage. After that I clicked the back button(android back button) and went to Firstpage.java and again clicked on other image. But this time also the same image stored. The category id didnt changed. The category id is not refreshing...How to refresh the category id? Any suggestion will be thankful.....

You are comparing two strings by == operator, instead you should compare by equals method, try following:
if(catid.equals("0"))
{
categorytype.setBackgroundResource(R.drawable.image1);
}
else if(catid.equals("1"))
{
categorytype.setBackgroundResource(R.drawable.image2);
}
else if(catid.equals(2"))
{
categorytype.setBackgroundResource(R.drawable.image3);
}

Don't use static variables for this. Pass the category ID to your Nextpage activity through the intent. In Firstpage.java:
public static final String CATEGORY_KEY = "category";
category1.setOnClickListener(new View.OnClickListener()
{
public void onClick(View view)
{
Intent myIntent = new Intent(this,Nextpage.class);
myIntent.putExtra(CATEGORY_KEY, "0");
startActivityForResult(myIntent, 0);
}
});
Then retrieve it in the onCreate(Bundle) method of Nextpage.java:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Intent intent = getIntent();
String categoryid = intent.getStringExtra(Firstpage.CATEGORY_KEY);
. . .
}
The reason your method doesn't work is that Nextpage.catid is initialized when the class is loaded, but the assignment statement is not executed again unless the class is unloaded and needs to be reloaded.

I think problem is here you are comparing String values using this if(catid=="0") Which you should be compare it using if(catid.trim().equals("0"))
Update this change in your code and check it.