';android.text.Editable android.widget.EditText.getText()';关于空对象引用
每当我单击该按钮时,我都会得到“在空对象引用上尝试调用虚拟方法”android.text.Editable android.widget.EditText.getText()。请帮忙';android.text.Editable android.widget.EditText.getText()';关于空对象引用,android,nullpointerexception,Android,Nullpointerexception,每当我单击该按钮时,我都会得到“在空对象引用上尝试调用虚拟方法”android.text.Editable android.widget.EditText.getText()。请帮忙 protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); edt
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
edt = (EditText) findViewById(R.id.edit);
b1 = (Button) findViewById(R.id.button);
b1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent i = new Intent(MainActivity.this, Main2Activity.class);
startActivity(i);
}
})
}
String tt(){
return (edt.getText()+"");
}
public class Main2Activity extends AppCompatActivity {
MainActivity ob = new MainActivity();
private WebView mywebview;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
mywebview=(WebView)findViewById(R.id.abc);
WebSettings webSettings=mywebview.getSettings();
webSettings.setJavaScriptEnabled(true);
mywebview.loadUrl(ob.tt());
mywebview.setWebViewClient(new WebViewClient());
}
}
MainActivity ob=新的MainActivity()
将获得该类的一个简单对象,而不是当前正在运行的实际对象,因此ob
在这种情况下是无用的,请删除ob
相关代码并使用Intent
传递数据
在第一个main活动中
b1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent i = new Intent(MainActivity.this, Main2Activity.class);
i.putExtra("data",edt.getText().toString());
// ^^^^ pass data
startActivity(i);
}
})
在main2活动中
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
mywebview=(WebView)findViewById(R.id.abc);
WebSettings webSettings=mywebview.getSettings();
webSettings.setJavaScriptEnabled(true);
mywebview.loadUrl(getIntent().getStringExtra("data"));
// ^^^^^
mywebview.setWebViewClient(new WebViewClient());
}
也读