Question

我得到＆＃34;尝试调用虚方法＆＃39; android.text.Editable android.widget.EditText.getText（）＆＃39;在null对象引用＆＃34;每当我点击按钮。请帮忙

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());
    }
}

Answer 1

MainActivity ob = new MainActivity();会为您提供此类的简单对象，而不是当前正在运行的实际对象，因此ob在这种情况下无效，删除ob相关代码并使用{{1}传递数据

在第一个Intent

MainActivity

在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); } })

Main2Activity

另请阅读How do I pass data between Activities in Android application?

＆＃39; android.text.Editable android.widget.EditText.getText（）＆＃39;在null对象引用上

1 个答案: