我正在尝试使用BroadcastReceiver从服务中获取数据，并且我能够在日志中显示该数据，但是当我尝试使用Bundle这样发送数据时
@Override
protected void onStart() {
myReceiver = new MainActivity.MyReceiver();
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction(MediaService.MY_ACTION);
registerReceiver(myReceiver, intentFilter);
super.onStart();
}
private class MyReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context arg0, Intent arg1) {
// TODO Auto-generated method stub
String datapa = arg1.getStringExtra("DATAPASSED");
String datap2 = arg1.getStringExtra("ALBUM_DATA");
Log.d("TITLE OF SONG",datapa);
Log.d("ALBUM",datap2);
Bundle bundle = new Bundle();
bundle.putString("Title",datapa);
bundle.putString("album", datap2);
Songs someFragment = new Songs();
someFragment.setArguments(bundle);
}
}
并获取此类数据
String strtext = getArguments().getString("album");
if (strtext!=null){
textView.setText(strtext);
}else {
textView.setText(String.valueOf(songarr.size()));
}
String title = getArguments().getString("Title");
if (title!=null){
textView.setText(title);
}else {
textView.setText("Total Songs");
}
我遇到错误
java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String android.os.Bundle.getString(java.lang.String)' on a null object reference
at beatbox.neelay.anotherbeat.Fragment.Songs.onCreateView(Songs.java:55)
at android.support.v4.app.Fragment.performCreateView(Fragment.java:2184)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1298)
at android.support.v4.app.FragmentManagerImpl.moveFragmentsToInvisible(FragmentManager.java:2323)
at android.support.v4.app.FragmentManagerImpl.executeOpsTogether(FragmentManager.java:2136)
at android.support.v4.app.FragmentManagerImpl.optimizeAndExecuteOps(FragmentManager.java:2092)
at android.support.v4.app.FragmentManagerImpl.execSingleAction(FragmentManager.java:1969)
at android.support.v4.app.BackStackRecord.commitNowAllowingStateLoss(BackStackRecord.java:620)
at android.support.v4.app.FragmentPagerAdapter.finishUpdate(FragmentPagerAdapter.java:143)
at com.antonyt.infiniteviewpager.InfinitePagerAdapter.finishUpdate(InfinitePagerAdapter.java:67)
at android.support.v4.view.ViewPager.populate(ViewPager.java:1268)
at android.support.v4.view.ViewPager.populate(ViewPager.java:1116)
at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1642)
at android.view.View.measure(View.java:18811)
at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:716)
at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:462)
at android.view.View.measure(View.java:18811)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952)
at android.support.design.widget.CoordinatorLayout.onMeasureChild(CoordinatorLayout.java:714)
at android.support.design.widget.CoordinatorLayout.onMeasure(CoordinatorLayout.java:786)
at android.view.View.measure(View.java:18811)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
at android.support.v7.widget.ContentFrameLayout.onMeasure(ContentFrameLayout.java:139)
at android.view.View.measure(View.java:18811)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1465)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:748)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:630)
at android.view.View.measure(View.java:18811)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
at android.view.View.measure(View.java:18811)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1465)
at android.widget.LinearLayout.measureVertical(LinearLayout.java:748)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:630)
at android.view.View.measure(View.java:18811)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5952)
at android.widget.FrameLayout.onMeasure(FrameLayout.java:194)
at com.android.internal.policy.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2645)
at android.view.View.measure(View.java:18811)
at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:2127)
at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1243)
at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1479)
at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1134)
at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6045)
at android.view.Choreographer$CallbackRecord.run(Choreographer.java:860)
at android.view.Choreographer.doCallbacks(Choreographer.java:672)
at android.view.Choreographer.doFrame(Choreographer.java:608)
at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:846)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Loop
事情是我在播放歌曲，所以当用户点击按钮时，服务会将当前播放的歌曲数据发送到活动，然后从活动发送到片段，当歌曲没有播放时，它只会显示总歌曲，但当我运行应用程序崩溃说空字符串，但我设置else语句他们我做错了什么？任何提示都会有帮助。片段将无法获取数据，直到用户点击主要内容列表。Using the same bundle way i am able to send the data to other fragment这里的初始值为null我是如何解决此问题的。
答案 0 :(得分：0)
查看你的getArguments是否先不为空
if（getArguments（）！= null） //然后做你正在做的事情，即从捆绑中拉出字符串。
答案 1 :(得分：0)
不是间接传递数据，而是使用直接方式，我在服务中设置如此
Intent intent = new Intent();
intent.setAction(MY_ACTION);
intent.putExtra("DATAPASSED", activeAudio.getTitle());
intent.putExtra("ALBUM_DATA",activeAudio.getAlbum());
sendBroadcast(intent);
在我的片段中
@Override
public void onStart() {
super.onStart();
myReceiver = new MyReceiver();
IntentFilter intentFilter = new IntentFilter();
intentFilter.addAction(MediaService.MY_ACTION);
getActivity().registerReceiver(myReceiver, intentFilter);
}
private class MyReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context arg0, Intent arg1) {
// TODO Auto-generated method stub
String datapa = arg1.getStringExtra("DATAPASSED");
String datap2 = arg1.getStringExtra("ALBUM_DATA");
Log.d("TITLE OF SONG", datapa);
Log.d("ALBUM", datap2);
textView.setText(datapa);
textView1.setText(datap2);
}
}
希望这会对某人有所帮助。