货币转换器android应用程序中的运行时致命错误

Question

当我按下按钮时，应用程序会崩溃。每个转换“国名”功能都是一个按钮。我会在评论中发布错误。提前道谢。

public class MainActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    public void convertIndia(View view){ convert(64.7,"Rupees"); }
    public void convertEurope(View view){ convert(0.85,"Euros"); }
    public void convertBritish(View view){ convert(0.78,"Pounds"); }
    public void convertUae(View view) { convert(3.67,"Dhiram"); }
    public void convertCanada(View view){ convert(1.26,"Ca Dollors"); }     
    public void convertAustralia(View view) { convert(1.26,"Aus Dollors"); }

    public void convert(double other,String country){

        EditText editText = (EditText) findViewById(R.id.value);
        Double usdValue = Double.parseDouble(editText.getText().toString());

        Log.i("USDVAL",usdValue.toString());
        Log.i("EDITTEXT",editText.toString());

        Double finalvalue = usdValue * other;

        Toast.makeText(MainActivity.this, String.format("%.2f", finalvalue) + " " + country, Toast.LENGTH_LONG).show();
    }
}

<Button
    android:id="@+id/india"
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content"
    android:layout_alignBottom="@+id/british"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:layout_below="@+id/value"
    android:layout_toStartOf="@+id/british"
    android:onClick="convertIndia"
    android:text="IND_Rupee"
    tools:layout_editor_absoluteX="131dp"
    tools:layout_editor_absoluteY="70dp" />

Answer 1

您应该尝试onClickListener而不是Android：onClick。示例：

Button button = (Button) findViewById(R.id.yourButtonId);   
button.setOnClickListener(new OnClickListener() {
    @Override
    public void onClick(View view) {
        callYourMethodHere();
    }
});

把这个放在Create里面，你就可以开始了