我照著網上的代碼打 系統提示我錯誤(提示說:無法在空物件參考上啟動活動組件資訊)代碼如下:
package com.example.fragementtest;
import androidx.appcompat.app.AppCompatActivity;
import androidx.fragment.app.Fragment;
import androidx.fragment.app.FragmentManager;
import androidx.fragment.app.FragmentTransaction;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
public class MainActivity extends AppCompatActivity { Button btn1; Button btn2; Intent a,b; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); btn1 = findViewById(R.id.button1); btn1.setOnClickListener(new BL()); btn2 = findViewById(R.id.button2); btn2.setOnClickListener(new BL()); replaceFragment(new RightFra()); } private class BL implements View.OnClickListener{ public void onClick(View v) { switch (v.getId()){ case R.id.button1: a = new Intent(MainActivity.this,Another.class); startActivity(a); break; case R.id.button2: b = new Intent(MainActivity.this,RightFra.class); startActivity(b); break; default: break; } } } private void replaceFragment(Fragment fragment){ FragmentManager fragmentManager = getSupportFragmentManager(); FragmentTransaction transaction = fragmentManager.beginTransaction(); transaction.replace(R.id.right_layout,fragment); transaction.commit(); }
}
哪位大神可以指導一下我,看看這個代碼錯在哪里,怎么修改
uj5u.com熱心網友回復:
1. 學會除錯,看哪一行出錯了,就知道哪里出問題。2. 看錯誤描述,是intent為Null。
3. 另外,你的代碼是不是應該格式化一下?
uj5u.com熱心網友回復:
打漢字有啥用,貼出來uj5u.com熱心網友回復:
將你的錯誤的log資訊貼出來轉載請註明出處,本文鏈接:https://www.uj5u.com/yidong/85775.html
標籤:Android
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