视频查看的onpreparedlistener（）出错

Question

我希望在视频加载视频之前有一个进度条。但我得到以下错误。我还添加了所有必要的导入。

我正在使用AIDE IN ANDROID

这是我的代码

public class MainActivity extends Activity{
 ProgressBar progressBar = null;

VideoView videoView = null;

String videoUrl = "http://www.androidbegin.com/tutorial/AndroidCommercial.3gp";

Context context = null;

@Override
public void onCreate(Bundle iclic) {
    super.onCreate(iclic);

    context = null;

    requestWindowFeature(Window.FEATURE_NO_TITLE);

    setContentView(R.layout.main);

    videoView = (VideoView) findViewById(R.id.videoview);
    progressBar = (ProgressBar) findViewById(R.id.progressbar);

    Uri videoUri = Uri.parse(videoUrl);

    videoView.setVideoURI(videoUri);
    videoView.start();

    progressBar.setVisibility(View.VISIBLE);

    videoView.setOnPreparedListener(new OnPreparedListener() {
        @Override
        public void onPrepared(MediaPlayer mp) {
            // TODO Auto-generated method stub
            mp.start();
            mp.setOnVideoSizeChangedListener(new OnVideoSizeChangedListener() {
                @Override
                public void onVideoSizeChanged(MediaPlayer mp, int arg1,
                        int arg2) {
                    // TODO Auto-generated method stub
                    progressBar.setVisibility(View.GONE);
                    mp.start();
                }
            });

        }
    });

}

}

没有理解问题所在！

Answer 1

试试这个，做得很完美

将[Code] var OptionPage: TInputOptionWizardPage; procedure InitializeWizard(); begin OptionPage := CreateInputOptionPage( wpWelcome, 'Choose installation options', 'Who should this application be installed for?', 'Please select whether you wish to make this software available for all users ' + 'or just yourself.', True, False); OptionPage.Add('&Anyone who uses this computer'); OptionPage.Add('&Only for me'); if IsAdminLoggedOn then begin OptionPage.Values[0] := True; end else begin OptionPage.Values[1] := True; OptionPage.CheckListBox.ItemEnabled[0] := False; end; end; function NextButtonClick(CurPageID: Integer): Boolean; begin if CurPageID = OptionPage.ID then begin if OptionPage.Values[1] then begin { override the default installation to program files ({pf}) } WizardForm.DirEdit.Text := ExpandConstant('{userappdata}\My Program') end else begin WizardForm.DirEdit.Text := ExpandConstant('{pf}\My Program'); end; end; Result := True; end; 替换为new OnPreparedListener()，将new MediaPlayer.OnPreparedListener()替换为new OnVideoSizeChangedListener()