TextView作為屬性？

Question

我想使用我的TextView作為屬性

private TextView up = (TextView) findViewById(R.id.tv_up);
private TextView mid = (TextView) findViewById(R.id.tv_mid);
private TextView down = (TextView) findViewById(R.id.tv_down);

而不是永遠定義它：

public void onButtonClickUp(View v) {
        TextView up = (TextView) findViewById(R.id.tv_up);
        TextView mid = (TextView) findViewById(R.id.tv_mid);
        TextView down = (TextView) findViewById(R.id.tv_down);
        <..>
}

public void onButtonClickDown(View v) {
        TextView up = (TextView) findViewById(R.id.tv_up);
        TextView mid = (TextView) findViewById(R.id.tv_mid);
        TextView down = (TextView) findViewById(R.id.tv_down);
        <..>
}

上部方法在我的android設備上產生force close error 。 如何解決這個問題或通常有可能嗎？

謝謝！

Answer 1

public class TestActivity extends Activity {

    private TextView up;
    private TextView mid;
    private TextView down;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

     up = (TextView) findViewById(R.id.tv_up);
     mid = (TextView) findViewById(R.id.tv_mid);
     down = (TextView) findViewById(R.id.tv_down);

}

我不確定為什么您的應用會崩潰，但是通過這樣聲明/分配小部件，您將避免很多麻煩……整個活動只有一次。