Question

我已经制作了代码并且没有错误，但 logcat 显示NullPointerException。这是我传递和捕获每个活动的值的代码。请帮我解决这个问题。

第一项活动：

try {
    Intent in = new Intent();
    in.setClass(p_daftar_pelanggan.this, ubah_data_pelanggan.class);
    in.putExtra("id", eid.getText().toString());
    in.putExtra("nama", tnama.getText().toString());
    in.putExtra("alamat", ealamat.getText().toString());
    in.putExtra("no_hp", ehp.getText().toString());
    startActivity(in);
}
catch(NullPointerException ex)
{
}

第二项活动：

Bundle b = getIntent().getExtras();
String idpgu = b.getString("id");
String namapgu = b.getString("nama");
String alamatpgu = b.getString("alamat");
String hppgu = b.getString("no_hp");

idp.setText(idpgu);
idp.setKeyListener(null);

nama.setText(namapgu);
ealamat.setText(alamatpgu);
hp.setText(hppgu);

Answer 1

在第二项活动中尝试以下内容：

Intent intent = getIntent();
String idpgu = intent.getStringExtra("id");

Answer 2

你在FirstActivity中使用Intent添加额外内容但是使用Bundle来接收它，这就是为什么你有NullPointerException，因为SecondActivity正在寻找不同位置的值。在第二个实践中执行以下操作

Intent intent = getIntent(); 
String idpgu = intent.getStringExtra("id");
String namapgu = intent.getStringExtra("nama");
String alamatpgu = intent.getStringExtra("alamat");
String hppgu = intent.getStringExtra("no_hp");
// Check Null for each Values e.g. 
  if (idpgu.trim().equals(" ")) 
{ idpgu = "null"; 
}

Answer 3

您可以将Bundle用于此目的：

Activity destActivity = new Activty();
Bundle b = new Bundle();
destActivity.putString("TAG_ForValue",YourValue.getText().toString());
destActivity.setArguments(b);

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

在你的destActivity中：

Bundle bundle = getArguments();

if(bundle !=null)
   String value =  bundle.getString("TAG_ForValue");

Answer 4

You are sending and receiving the values correctly, but probably some values are null, you can validate setting an empty string instead of a null value:

   Bundle b = getIntent().getExtras();
   String idpgu = (b.getString("id") != null)? b.getString("id") : "";
   String namapgu = (b.getString("nama") != null)? b.getString("nama") : "";
   String alamatpgu = (b.getString("alamat") != null)? b.getString("alamat") : "";
   String hppgu = (b.getString("no_hp") != null)? b.getString("no_hp") : "";

Answer 5

@YRO：

请检查您的buffer声明。你的try catch block声明是什么。你的catch阻止是空的，这就是catch抛出的原因。

因此，首先，您可以检查如何从Java文档中处理NullPointerException块。

我希望它会对你有所帮助。

将值从一个活动发送到另一个活动

5 个答案: