java - 编译器无法识别 setOnClickListener(....);

Question

我正在 ActivityMain.java 中创建按钮编译器无法识别 onSetClickListener。我错过了什么？

package com.example.mydiceapp;

import android.os.Bundle;
import android.view.View;
import android.widget.Button;

import androidx.appcompat.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity {

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


    Button rollButton = findViewById(R.id.blahblah);

    rollButton.setOnClickListener(new View.OnClickListener());

}

Answer 1

您需要使用findViewById()并在onCreate()方法中使用setOnClickListener()

试试这个

package com.example.mydiceapp;

import android.os.Bundle;
import android.view.View;
import android.widget.Button;

import androidx.appcompat.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity {

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

         Button rollButton = findViewById(R.id.blahblah);

         rollButton.setOnClickListener(new View.OnClickListener());
    }




}