Question

我是Android新手，当我点击导航按钮时，我的应用程序失败或停止工作，导航按钮应该指向另一个活动。这是我导航到下一个活动的代码。

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

My SelectedItemsControl.class代码：

public class SelectedItemsControl extends AppCompatActivity {

    ListView lv2 ;
    ArrayList<String> CheckoutList ;
    ArrayAdapter adapter;

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

lv2 =  (ListView) findViewById(R.id.listviewtwo);
        CheckoutList = new ArrayList<>();
        adapter = new ArrayAdapter(this, android.R.layout.simple_list_item_2,CheckoutList);
lv2.setAdapter(adapter);

    }
}

Answer 1

您的代码应该是

public void checkout(View view){
    Intent intent = new Intent(FirstActivity.this, SecondActivity.class); // no space in class name
    startActivity(intent); }//no space between Start and Activity.

Answer 2

检查清单。您的活动是否已宣布

<activity android:name=".SelectedItemsControl" />

希望它对你有所帮助。如果你有一些不同的问题，请问我会帮助你，如果这没有帮助尝试第二个选项

public void checkout(View view){
    Intent intent = new Intent(FirstActivity.this, SecondActivity.class); 
    startActivity(intent); }

尝试在第二个Activity中注释代码。如果您在第二次活动中有任何错误，它会有所帮助。

public class SelectedItemsControl extends AppCompatActivity {

    ListView lv2 ;
    ArrayList<String> CheckoutList ;
    ArrayAdapter adapter;

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

/*lv2 =  (ListView) findViewById(R.id.listviewtwo);
        CheckoutList = new ArrayList<>();
        adapter = new ArrayAdapter(this, android.R.layout.simple_list_item_2,CheckoutList);
lv2.setAdapter(adapter);*/

    }
}

导航时Android应用停止

2 个答案: