16
votes

I have a problem, I want to click on the list, calling a new activity and rename the button to another name.

I tried several things, nothing worked, can someone please help me?

My class EditarTimes:

private AdapterView.OnItemClickListener selecionarTime = new AdapterView.OnItemClickListener() {

    public void onItemClick(AdapterView arg0, View arg1, int pos, long id) {
        t = times.get(pos);

        CadastroTimes cad = new CadastroTimes();
        CadastroTimes.salvar.setText("Alterar");
        Intent intent = new Intent(EditarTimes.this, CadastroTimes.class);
        startActivity(intent);


    }

};
public class CadastroTimes extends AppCompatActivity {

    private Time t;
    private timeDatabase db;
    private EditText edID;
    private EditText edNome;
    public Button salvar;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_cadastro_times);

        edID = (EditText) findViewById(R.id.edID);
        edNome = (EditText) findViewById(R.id.edNome);
        db = new timeDatabase(getApplicationContext());
        salvar = (Button) findViewById(R.id.btnCadastrar);
        salvar.setText("Cadastrar");
        String newString;
        if (savedInstanceState == null) {
            Bundle extras = getIntent().getExtras();
            if(extras == null) {
                newString= null;
            } else {
                newString= extras.getString("Alterar");
            }
        } else {
            newString= (String) savedInstanceState.getSerializable("Alterar");
        }

        //button in CadastroTimes activity to have that String as text
        System.out.println(newString + " AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA");
        salvar.setText(newString);
    }

    public void salvarTime(View v) {
        t = new Time();
        t.setNome(edNome.getText().toString());

        if (salvar.getText().equals("Alterar")) {
            db.atualizar(t);
            exibirMensagem("Time atualizado com sucesso!");
        } else {
            db.salvar(t);
            exibirMensagem("Time cadastrado com sucesso!");
        }

        Intent intent = new Intent(this, EditarTimes.class);
        startActivity(intent);

    }


    private void limparDados() {
        edID.setText("");
        edNome.setText("");
        edNome.requestFocus();
    }

    private void exibirMensagem(String msg) {
        Toast.makeText(getApplicationContext(), msg, Toast.LENGTH_LONG).show();
    }

}
public class EditarTimes extends AppCompatActivity {

    private Time t;
    private List times;
    private timeDatabase db;
    private ListView lvTimes;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_editar_times);

        lvTimes = (ListView) findViewById(R.id.lvTimes);
        lvTimes.setOnItemClickListener(selecionarTime);
        lvTimes.setOnItemLongClickListener(excluirTime);
        times = new ArrayList();
        db = new timeDatabase(getApplicationContext());
        atualizarLista();
    }

    private void excluirTime(final int idTime) {


        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        builder.setTitle("Excluir time?")
                .setIcon(android.R.drawable.ic_dialog_alert)
                .setMessage("Deseja excluir esse time?")
                .setCancelable(false)
                .setPositiveButton(getString(R.string.sim),
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog, int id) {
                                if (db.deletar(idTime)) {
                                    atualizarLista();
                                    exibirMensagem(getString(R.string.msgExclusao));
                                } else {
                                    exibirMensagem(getString(R.string.msgFalhaExclusao));
                                }

                            }
                        })
                .setNegativeButton(getString(R.string.nao),
                        new DialogInterface.OnClickListener() {
                            public void onClick(DialogInterface dialog, int id) {
                                dialog.cancel();
                            }
                        });
        builder.create();
        builder.show();

        atualizarLista();

    }

    private void atualizarLista() {

        times = db.listAll();
        if (times != null) {
            if (times.size() > 0) {
                TimeListAdapter tla = new TimeListAdapter(
                        getApplicationContext(), times);
                lvTimes.setAdapter(tla);
            }

        }

    }

    private AdapterView.OnItemClickListener selecionarTime = new AdapterView.OnItemClickListener() {

        public void onItemClick(AdapterView arg0, View arg1, int pos, long id) {
            t = times.get(pos);

            Intent intent = new Intent(EditarTimes.this, CadastroTimes.class);
            String strName = "Alterar";
            intent.putExtra("Alterar", strName);
            startActivity(intent);




            //preecherDados(t);

        }

    };

    private AdapterView.OnItemLongClickListener excluirTime = new AdapterView.OnItemLongClickListener() {

        public boolean onItemLongClick(AdapterView arg0, View arg1,
                                       int pos, long arg3) {
            excluirTime(times.get(pos).getId());
            return true;
        }


    };

    /*private void preecherDados(Time time) {
        edID.setText(String.valueOf(time.getId()));
        edNome.setText(time.getNome());
    }*/

    private void exibirMensagem(String msg) {
        Toast.makeText(getApplicationContext(), msg, Toast.LENGTH_LONG).show();
    }

    public void telaCadastrar(View view) {
        Intent intent = new Intent(this, CadastroTimes.class);
        startActivity(intent);
    }

    public void botaoSair(View view) {
        Intent intent = new Intent(this, TelaInicial.class);
        startActivity(intent);
    }
}
10
if button is in CadastroTimes then do it CadastroTimes instead of in EditarTimesρяσѕρєя K
The button is in CadastroTimes.class, everything is working, I just need to click on a list item, call activity CadastroTimes and change the button name.Alan Santos

10 Answers

13
votes

You can pass the button caption to CadastroTimes with intent as

Intent intent = new Intent(EditarTimes.this, CadastroTimes.class);
intent.putExtra("buttontxt","Changed Text");
startActivity(intent);

Then in CadastroTimes.java set the text of the button to the new value that you passed. The code will look like:

button = (Button)findViewById(R.id.button); // This is your reference from the xml. button is my name, you might have your own id given already.
Bundle extras = getIntent().getExtras();
String value = ""; // You can do it in better and cleaner way
if (extras != null) {
    value = extras.getString("buttontxt");
}
button.setText(value);

Do remember to do it in onCreate after setContentView

4
votes
//From Activity
Intent intent = new Intent(EditarTimes.this, CadastroTimes.class);
intent.putExtra("change_tag", "text to change");
startActivity(intent);

//To Activity

public void onCreate(..){

    Button changeButton = (Button)findViewById(R.id.your_button);
    // Button to set received text
    Intent intent = getIntent();

    if(null != intent && 
             !TextUtils.isEmpty(intent.getStringExtra("change_tag"))) {


        String changeText = intent.getStringExtra("change_tag");
        // Extracting sent text from intent
        
        changeButton.setText(changeText);
        // Setting received text on Button

     }
}
2
votes

1: Use intent.putExtra() to share a value from one activity another activity, as:

In ActivityOne.class :

startActivity(
    Intent(
        applicationContext, 
        ActivityTwo::class.java
    ).putExtra(
        "key", 
        "value"
    )
)

In ActivityTwo.class :

var value = ""
if (intent.hasExtra("key")
    value = intent.getStringExtra("key")

2: Modify button text programatically as:

btn_object.text = value

Hope this will help you

0
votes

For changing the button text:

  1. Use a static method to call from the other activity to directly modify the button caption.
  2. Use an intent functionality, which is preferable.
  3. Use an Interface and implement it, which is used for communicating between activities or fragment in a manner of fire and forget principle.
0
votes

Now, i got you:

Your EditarTimes activity with listview:

//set setOnItemClickListener

 youtListView.setOnItemClickListener(new android.widget.AdapterView.OnItemClickListener() {
    @Override
    public void onItemClick(AdapterView<?> parent, View view,int position, long id) {

    Intent i = new Intent(EditarTimes.this, CadastroTimes.class);  
 //text which you want to display on the button to CadastroTimes activity
   String strName = "hello button"; 
    i.putExtra("STRING_I_NEED", strName);             
                }
            });

In CadastroTimes activity,

under onCreate() method, get the text string as:-

String newString;
if (savedInstanceState == null) {
    Bundle extras = getIntent().getExtras();
    if(extras == null) {
        newString= null;
    } else {
        newString= extras.getString("STRING_I_NEED");
    }
} else {
    newString= (String) savedInstanceState.getSerializable("STRING_I_NEED");
}

//button in CadastroTimes activity to have that String as text yourButton.setText(newString);

0
votes

Ok, so the first step would be to take the button you want and make it a public static object (and put it at the top of the class).

public static Button button;

Then you can manipulate that using this in another class:

 ClassName.button.setText("My Button");

In your case it is

CadastroTimes.salvar.setText("Alterar");
0
votes

if you want to change value from that do not do not go the activity via intent you can use file to save value to file or you have multiple values the use database and access the value oncreate to set the value of text....

0
votes

In my case, I had to send an EditText value from a Dialog styled Activity, which then got retrieved from a Service.. My Example is similar to some of the above answers, which are also viable.

TimerActivity.class

public void buttonClick_timerOK(View view) {

    // Identify the (EditText) for reference:
    EditText editText_timerValue;
    editText_timerValue = (EditText) findViewById(R.id.et_timerValue);

    // Required 'if' statement (to avoid NullPointerException):
    if (editText_timerValue != null) {

        // Continue with Button code..

        // Convert value of the (EditText) to a (String)
        String string_timerValue;
        string_timerValue = editText_timerValue.getText().toString();

        // Declare Intent for starting the Service
        Intent intent = new Intent(this, TimerService.class);
        // Add Intent-Extras as data from (EditText)
        intent.putExtra("TIMER_VALUE", string_timerValue);
        // Start Service
        startService(intent);

        // Close current Activity
        finish();

    } else {
        Toast.makeText(TimerActivity.this, "Please enter a Value!", Toast.LENGTH_LONG).show();
    }
}


And then inside my Service class, I retrieved the value, and use it inside onStartCommand.

TimerService.class

// Retrieve the user-data from (EditText) in TimerActivity
    intent.getStringExtra("TIMER_VALUE");   //  IS THIS NEEDED, SINCE ITS ASSIGNED TO A STRING BELOW TOO?

    // Assign a String value to the (EditText) value you retrieved..
    String timerValue;
    timerValue = intent.getStringExtra("TIMER_VALUE");

    // You can also convert the String to an int, if needed.

    // Now you can reference "timerValue" for the value anywhere in the class you choose.


Hopefully my contribution helps!
Happy coding!

0
votes

Accessing view reference of another Activity is a bad practice. Because there is no guarantee if the reference is still around by the time you access it (considering the null reference risk).

What you need to do is to make your other Activity read values (which you want to display) from a data source (e.g. persistence storage or shared preferences), and the other Activity manipulates these values. So it appears as if it changes the value of another activity, but in reality it takes values from a data source.

0
votes

Using SharedPreferences:

Note: SharedPreferences saves data in the app if you close it but it will be lost when it has been deleted.

In EditarTimes.java:

private AdapterView.OnItemClickListener selecionarTime = new AdapterView.OnItemClickListener() {

    public void onItemClick(AdapterView arg0, View arg1, int pos, long id) {
        t = times.get(pos);

        SharedPreferences.Editor editor = getSharedPreferences("DATA", MODE_PRIVATE).edit();
        editor.putString("btnText", "Your desired text");
        editor.apply();
        Intent intent = new Intent(EditarTimes.this, CadastroTimes.class);
        startActivity(intent);

    }

};

In CadastroTimes.java

public Button salvar;

salvar.setText(getSharedPreferences("DATA", MODE_PRIVATE).getString("btnText", ""));
//note that default value should be blank