Question

我正在尝试在活动之间发送数据，这是发送代码：

  public void sendToFavorites(Context context){
        String vID,vThumbnail,vTitle;
        Bundle extras = new Bundle();

        vID = sendResult.getId().getVideoId();
        vThumbnail = sendResult.getSnippet().getThumbnails().getMedium().getUrl();
        vTitle = sendResult.getSnippet().getTitle();
        extras.putString("id",vID);

        intent = new Intent(context,Favorites.class);
        intent.putExtras(extras);
        startActivity(intent); <----- Application crash here.
}

这是logcat：

05-18 18:39:00.560  28528-28528/project.youtubeplayer E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: project.youtubeplayer, PID: 28528
java.lang.NullPointerException: Attempt to invoke virtual method 'android.app.ActivityThread$ApplicationThread android.app.ActivityThread.getApplicationThread()' on a null object reference
        at android.app.Activity.startActivityForResult(Activity.java:3745)
        at android.app.Activity.startActivityForResult(Activity.java:3706)
        at android.support.v4.app.FragmentActivity.startActivityForResult(FragmentActivity.java:817)
        at android.app.Activity.startActivity(Activity.java:4016)
        at android.app.Activity.startActivity(Activity.java:3984)
        at project.youtubeplayer.MainActivity.sendToFavorites(MainActivity.java:183)
        at project.youtubeplayer.YtAdapter$1.onClick(YtAdapter.java:77)
        at android.view.View.performClick(View.java:4780)
        at android.view.View$PerformClick.run(View.java:19866)
        at android.os.Handler.handleCallback(Handler.java:739)
        at android.os.Handler.dispatchMessage(Handler.java:95)
        at android.os.Looper.loop(Looper.java:135)
        at android.app.ActivityThread.main(ActivityThread.java:5254)
        at java.lang.reflect.Method.invoke(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:372)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)

致电sendToFavroites：

        mHolder.mVideoFavorite.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            AppUtils.showToast(result.getSnippet().getTitle() + " Was added to favorites.");
            m.sendResult = result;
            m.sendToFavorites(mActivity);
        }
    });

YtAdapter：

public class YtAdapter extends BaseAdapter {
private Activity mActivity = null;
private List<SearchResult> mVideoList = null;
private LayoutInflater mLayoutInflater = null;
MainActivity m = new MainActivity();

public YtAdapter(Activity iActivity){
    mActivity = iActivity;
    mLayoutInflater = LayoutInflater.from(mActivity);
}
public void setmVideoList(List<SearchResult> mVideoList){
    this.mVideoList = mVideoList;
}

@Override
public int getCount() {
    return (mVideoList == null)? (0):(mVideoList.size());
}

@Override
public Object getItem(int position) {
    return (mVideoList != null && mVideoList.size()>position)? (mVideoList.get(position)):(null);
}

@Override
public long getItemId(int position) {
    return position;
}

@Override
public View getView(final int position, View convertView, final ViewGroup parent) {
    final ViewHolder mHolder;
    if(convertView != null){
        mHolder = (ViewHolder)convertView.getTag();
    }else{
        mHolder = new ViewHolder();
        convertView = mLayoutInflater.inflate(R.layout.view_video_item,null);
        mHolder.mVideoThumbnail = (ImageView)convertView.findViewById(R.id.video_thumbnail);
        mHolder.mVideoTitle = (TextView)convertView.findViewById(R.id.video_title);
        mHolder.mVideoFavorite = (ImageView)convertView.findViewById(R.id.video_favorite);

        convertView.setTag(mHolder);
    }
    //Setting the data
    final SearchResult result = mVideoList.get(position);
    mHolder.mVideoTitle.setText(result.getSnippet().getTitle());

    //Loading the image
    Picasso.with(mActivity).load(result.getSnippet().getThumbnails().getMedium().getUrl()).into(mHolder.mVideoThumbnail);

    //OnClickListeners
    mHolder.mVideoFavorite.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            AppUtils.showToast(result.getSnippet().getTitle() + " Was added to favorites.");
            m.sendResult = result;
            m.sendToFavorites(mActivity);
        }
    });

    mHolder.mVideoThumbnail.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            AppUtils.showToast("Please click on title to start video");
        }
    });
    return  convertView;
}

private class ViewHolder{
    private TextView mVideoTitle = null;
    private ImageView mVideoThumbnail = null;

    //Testing
    private ImageView mVideoFavorite = null;
}

从MainActivity调用YtAdapter：

    @Override
public void completedRequest(Object... objects){
    //Dismiss the dialog
    if(mLoadingDialog != null && mLoadingDialog.isShowing())
        mLoadingDialog.dismiss();

    //Parse the response based on type of request
    Integer reqCode = (Integer) objects[0];
    if(reqCode == null || reqCode == 0)
        throw  new NullPointerException("Request Code's value is Invalid.");
    switch (reqCode){
        case SEARCH_VIDEO:
            if(mYtadapter == null){
                mYtadapter = new YtAdapter(this);
                mYtadapter.setmVideoList((List<SearchResult>)objects[1]);
                mVideoLsv.setAdapter(mYtadapter);
            }else{
                mYtadapter.setmVideoList((List<SearchResult>) objects[1]);
                mYtadapter.notifyDataSetChanged();
            }
            break;
    }
}

我试图在网上搜索该问题，但找不到任何答案.. 希望你们能帮助我。

Answer 1

试一试：

在activity中，定义context

final Context context = this;

在adapter中使用它而不是activity。

m.sendToFavorites(context);

因此，在adapter中，定义Context cxt;

public YtAdapter(Context _cxt){
 ....
 cxt = _cxt;
}

然后使用它如下：

intent = new Intent(cxt,Favorites.class);
        intent.putExtras(extras);
        cxt.startActivity(intent);

当我使用adapter时，我就这样走了。

希望它有所帮助。

StartActivity（）崩溃了应用程序

1 个答案: