android studio 按钮不起作用

Question

I created a android studio button for my app and when I click on the register button it doesn't work . I don't get any errors it just doesn't work . When the user clicks the register button I want to go to the login activity .

RegisterActivity.java :

import android.app.AlertDialog;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.toolbox.Volley;

import org.json.JSONException;
import org.json.JSONObject;

 public class RegisterActivity extends AppCompatActivity {

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

    final EditText etUsername = (EditText) findViewById(R.id.etUsername);
    final EditText etPassword = (EditText) findViewById(R.id.etPassword);
    final Button bRegister = (Button) findViewById(R.id.bRegister);

    bRegister.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            final String username = etUsername.getText().toString();
            final String password = etPassword.getText().toString();

            Response.Listener<String> responseListener = new Response.Listener<String>() {
                @Override
                public void onResponse(String response) {
                    try {
                        JSONObject jsonResponse = new JSONObject(response);
                        boolean success = jsonResponse.getBoolean("success");
                        if (success) {
                            Intent intent = new Intent(RegisterActivity.this, LoginActivity.class);
                            RegisterActivity.this.startActivity(intent);
                        } else {
                            AlertDialog.Builder builder = new AlertDialog.Builder(RegisterActivity.this);
                            builder.setMessage("Register Failed")
                                    .setNegativeButton("Retry", null)
                                    .create()
                                    .show();
                        }
                    } catch (JSONException e) {
                        e.printStackTrace();
                    }
                }
            };

            RegisterRequest registerRequest = new RegisterRequest( username, password, responseListener);
            RequestQueue queue = Volley.newRequestQueue(RegisterActivity.this);
            queue.add(registerRequest);
        }
    });
}

}

activity_register.xml :

 <Button
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="Register"
    android:id="@+id/bRegister"
    android:layout_below="@+id/etPassword"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:layout_marginTop="56dp"
    android:layout_alignRight="@+id/etPassword"
    android:layout_alignEnd="@+id/etPassword"
    android:clickable="true"
    android:onClick="OnClickListener" />

RegisterRequest :

import com.android.volley.Response;
import com.android.volley.toolbox.StringRequest;

import java.util.HashMap;
import java.util.Map;

public class RegisterRequest extends StringRequest {

 private static final String REGISTER_REQUEST_URL = "http://app.comxa.com/register.php";
private Map<String, String> params;

 public RegisterRequest(String username, String password, Response.Listener<String> listener){
    super(Method.POST, REGISTER_REQUEST_URL, listener, null);
    params = new HashMap<>();
    params.put("username", username);
    params.put("password", password);
}

@Override
public Map<String, String> getParams() {
    return params;
}
}

Answer 1

in xml, attribute android:onClick must content the name of your method instead of listener name, for instance:

android:onClick="mybutton"

and in class:

public void mybutton(View v){
    if(v.getId() == R.id.mybutton){
        //handle the click here and make whatever you want
  }
}

The other way to do that is using onClickListener as follows:

in xml:

android:id="@+id/mybutton"

and in class:

Button mybutton = (Button) findViewById(R.id.mybutton);
mybutton.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        //your code here
    }
});

Answer 2

You have two choices to do this:

1. Register onClickListener for your button and without onClick attribute in xml.
2. create method with input(View view) in java class and call the method name in your xml onClick attribute. In this way you dont need to register any listener for buttons.

Answer 3

Your button looks like it should work, but for clarity, you can check this

bRegister.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Log.d("HELLO", "Register Button Clicked");

Now, for reasons that "it doesn't work", you should check your Volley code. In particular, verify that the third parameter of RegisterRequest (the callback) is actually being used and executed.

You can verify that the callback is called with

@Override
public void onResponse(String response) {
    Log.d("HELLO", response);
    try {
        JSONObject jsonResponse = new JSONObject(response);

All you need to do is look at the logcat for those messages.

Answer 4

You have two choices to do this:

Register onClickListener for your button and without onClick attribute in xml. create method with input(View view) in Java class and call the method name in your xml onClick attribute. In this way you don't need to register any listener for buttons.

Answer 5

I figured the solution out, the problem lies in your PHP script. You probably want to check your domain name http://yourdomain.com/yourphpScript.php in JSONLint website and check whether it is valid JSON or not. Or post your PHP script.