加载片段时出现空白屏幕

Question

我有这个片段：

ThreatList.java

public class ThreatList extends Fragment {
private TableLayout table;
private TableRow row;

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

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.fragment_threat, container, false);
    table = view.findViewById(R.id.TableThreat);

    if(PcapFile.IsPcapOpen()){
        AddHeaders();
        AddData(PcapFile.GetIpSource(),
                PcapFile.GetIpDestination());
    }

    return view;
}


public void AddHeaders(){
    row = new TableRow(getActivity());
    row.setLayoutParams(new TableRow.LayoutParams(
            ViewGroup.LayoutParams.FILL_PARENT,
            ViewGroup.LayoutParams.WRAP_CONTENT));

    TextView host = new TextView(getActivity());
    host.setText("SOURCE");
    host.setTextColor(Color.BLACK);
    host.setTypeface(Typeface.DEFAULT, Typeface.BOLD);
    host.setPadding(5, 5, 5, 0);
    row.addView(host);

    TextView uri = new TextView(getActivity());
    uri.setText("DESTINATION");
    uri.setTextColor(Color.BLACK);
    uri.setPadding(5, 5, 5, 0);
    uri.setTypeface(Typeface.DEFAULT, Typeface.BOLD);
    row.addView(uri);

    table.addView(row, new TableLayout.LayoutParams(
            TableLayout.LayoutParams.FILL_PARENT,
            TableLayout.LayoutParams.WRAP_CONTENT));

    row = new TableRow(getActivity());
    row.setLayoutParams(new TableRow.LayoutParams(
            TableRow.LayoutParams.FILL_PARENT,
            TableRow.LayoutParams.WRAP_CONTENT));

    TextView divider = new TextView(getActivity());
    divider.setText("__");
    divider.setTextColor(Color.BLACK);
    divider.setPadding(5, 0, 0, 0);
    divider.setTypeface(Typeface.DEFAULT, Typeface.BOLD);
    row.addView(divider);

    TextView divider2 = new TextView(getActivity());
    divider2.setText("__");
    divider2.setTextColor(Color.BLACK);
    divider2.setPadding(5, 0, 0, 0);
    divider2.setTypeface(Typeface.DEFAULT, Typeface.BOLD);
    row.addView(divider2);

    table.addView(row, new TableLayout.LayoutParams(
            TableLayout.LayoutParams.FILL_PARENT,
            TableLayout.LayoutParams.WRAP_CONTENT));
}

public void AddData(ArrayList<String> source, ArrayList<String> destination){
    TextView data;

    for (int i = 0; i < source.size(); i++)
    {
        row = new TableRow(getActivity());
        row.setLayoutParams(new TableRow.LayoutParams(
                TableRow.LayoutParams.FILL_PARENT,
                TableRow.LayoutParams.WRAP_CONTENT));

        data = new TextView(getActivity());
        data.setText(source.get(i));
        data.setTextColor(Color.DKGRAY);
        data.setTypeface(Typeface.DEFAULT, Typeface.NORMAL);
        data.setPadding(5, 5, 5, 5);
        row.addView(data);

        data = new TextView(getActivity());
        data.setText(destination.get(i));
        data.setTextColor(Color.DKGRAY);
        data.setPadding(5, 5, 5, 5);
        data.setTypeface(Typeface.DEFAULT, Typeface.NORMAL);
        row.addView(data);

        table.addView(row, new TableLayout.LayoutParams(
                TableLayout.LayoutParams.FILL_PARENT,
                TableLayout.LayoutParams.WRAP_CONTENT));
    }
}
}

函数AddData（...）用于在行中添加适当的信息，然后将行添加到表中。但是这些信息是一堆真正的数据（字符串中的IP信息，可能是1000个ip数据）的收集，因此片段采用whyle来完全加载布局的内容：

fragment_threat.xml

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="org.nucleo.ami.appsentinel.TabFragments.ThreatList"
android:background="@color/grey">

<ScrollView
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_marginBottom="8dp"
    android:layout_marginLeft="8dp"
    android:layout_marginRight="8dp"
    android:layout_marginTop="8dp"
    tools:ignore="UselessParent">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical" >

        <HorizontalScrollView
            android:layout_width="match_parent"
            android:layout_height="match_parent">

            <LinearLayout
                android:layout_width="wrap_content"
                android:layout_height="match_parent"
                android:orientation="vertical" >

                <TableLayout
                    android:id="@+id/TableThreat"
                    android:layout_width="match_parent"
                    android:layout_height="match_parent">

                </TableLayout>
            </LinearLayout>
        </HorizontalScrollView>
    </LinearLayout>
</ScrollView>

并留下一个空白屏幕，直到片段finsh加载。如何在“加载窗口”中显示片段，同时内容已准备好显示？

我正在使用Tabbed活动的片段，每个标签使用不同的片段来显示自己的数据，但我发现了ThreatList.java片段的问题。

这是我的fragmentpageadapter：

public class SectionsPagerAdapter extends FragmentPagerAdapter {

    private Fragment http = new HttpList();
    private Fragment dns = new DnsList();
    private Fragment threat = new ThreatList();
    private Fragment resume = new ResumeList();

    SectionsPagerAdapter(FragmentManager fm) {
        super(fm);
    }

    @Override
    public Fragment getItem(int position) {
        // getItem is called to instantiate the fragment for the given page.
        // Return a PlaceholderFragment (defined as a static inner class below).
        //return PlaceholderFragment.newInstance(position + 1);
        switch (position) {
            case 0:
                return http;
            case 1:
                return dns;
            case 2:
                return threat;
            case 3:
                return resume;
        }
        return null;
    }

    @Override
    public int getCount() {
        return 4;
    }

    @Override
    public CharSequence getPageTitle(int position) {
        switch (position) {
            case 0:
                return getString(R.string.http_tab);
            case 1:
                return getString(R.string.dns_tab);
            case 2:
                return getString(R.string.threat_tab);
            case 3:
                return getString(R.string.resume_tab);
        }
        return null;
    }

    @Override
    public int getItemPosition(Object object) {
        return POSITION_NONE;
    }
}

Answer 1

您只需要在 onCreateView（）方法中扩充您的布局，并且所有其他组件初始化和操作都将在重写方法 onViewCreated（）上执行，以获取片段。

public class ThreatList extends Fragment {

private TableLayout table;
private TableRow row;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_threat, container, false);
}

@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
table = view.findViewById(R.id.TableThreat);

if(PcapFile.IsPcapOpen()){
    AddHeaders();
    AddData(PcapFile.GetIpSource(),
            PcapFile.GetIpDestination());
}

return view;
}


public void AddHeaders(){
row = new TableRow(getActivity());
row.setLayoutParams(new TableRow.LayoutParams(
        ViewGroup.LayoutParams.FILL_PARENT,
        ViewGroup.LayoutParams.WRAP_CONTENT));

TextView host = new TextView(getActivity());
host.setText("SOURCE");
host.setTextColor(Color.BLACK);
host.setTypeface(Typeface.DEFAULT, Typeface.BOLD);
host.setPadding(5, 5, 5, 0);
row.addView(host);

TextView uri = new TextView(getActivity());
uri.setText("DESTINATION");
uri.setTextColor(Color.BLACK);
uri.setPadding(5, 5, 5, 0);
uri.setTypeface(Typeface.DEFAULT, Typeface.BOLD);
row.addView(uri);
table.addView(row, new TableLayout.LayoutParams(
        TableLayout.LayoutParams.FILL_PARENT,
        TableLayout.LayoutParams.WRAP_CONTENT));

row = new TableRow(getActivity());
row.setLayoutParams(new TableRow.LayoutParams(
        TableRow.LayoutParams.FILL_PARENT,
        TableRow.LayoutParams.WRAP_CONTENT));

TextView divider = new TextView(getActivity());
divider.setText("__");
divider.setTextColor(Color.BLACK);
divider.setPadding(5, 0, 0, 0);
divider.setTypeface(Typeface.DEFAULT, Typeface.BOLD);
row.addView(divider);

TextView divider2 = new TextView(getActivity());
divider2.setText("__");
divider2.setTextColor(Color.BLACK);
divider2.setPadding(5, 0, 0, 0);
divider2.setTypeface(Typeface.DEFAULT, Typeface.BOLD);
row.addView(divider2);

table.addView(row, new TableLayout.LayoutParams(
        TableLayout.LayoutParams.FILL_PARENT,
        TableLayout.LayoutParams.WRAP_CONTENT));
 }

 public void AddData(ArrayList<String> source, ArrayList<String> destination){
TextView data;

for (int i = 0; i < source.size(); i++)
{
    row = new TableRow(getActivity());
    row.setLayoutParams(new TableRow.LayoutParams(
            TableRow.LayoutParams.FILL_PARENT,
            TableRow.LayoutParams.WRAP_CONTENT));

    data = new TextView(getActivity());
    data.setText(source.get(i));
    data.setTextColor(Color.DKGRAY);
    data.setTypeface(Typeface.DEFAULT, Typeface.NORMAL);
    data.setPadding(5, 5, 5, 5);
    row.addView(data);

    data = new TextView(getActivity());
    data.setText(destination.get(i));
    data.setTextColor(Color.DKGRAY);
    data.setPadding(5, 5, 5, 5);
    data.setTypeface(Typeface.DEFAULT, Typeface.NORMAL);
    row.addView(data);

    table.addView(row, new TableLayout.LayoutParams(
            TableLayout.LayoutParams.FILL_PARENT,
            TableLayout.LayoutParams.WRAP_CONTENT));
     }
    }
  }
}

希望这有帮助