如果进度条能够在不需要时消失,那就更好了。在applyMenuChoice中使用setVisibility.progressBar是否有问题?在PrintStatusTask().execute()中使用setVisibility.progressBar的问题是它会在运行时导致应用程序崩溃。
public class Controller extends Activity {
private ProgressBar progressBar;
...
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.controller);
progressBar = (ProgressBar)findViewById(R.id.progressBar);
...
private boolean applyMenuChoice(MenuItem item) {
switch (item.getItemId()) {
case R.id.menuStatus:
progressBar.setVisibility(View.VISIBLE);
new PrintStatusTask().execute();
progressBar.setVisibility(View.GONE);
...