ScrollView不会滚动包含Android中动态内容的LinearLayout

时间:2013-07-16 22:50:54

标签: android scrollview

我在ScrollView中有一个LinearLayout。我的布局如下:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <TextView
        android:id="@+id/degree_planner_step2_title"
        style="@style/standard_text_view_appearance"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" />

    <View
        android:id="@+id/degree_planner_divider"
        android:layout_width="match_parent"
        android:layout_height="2dp"
        android:background="@color/Science" />

    <ScrollView
        android:id="@+id/sv"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@color/Commerce"
        android:fillViewport="true">

        <LinearLayout
            android:id="@+id/degreeplanner2_lin_layout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical" >
        </LinearLayout>
    </ScrollView>
</LinearLayout>

添加我的ListViews后,如果fillViewPort为true,它会扩展所有内容,但最后一个列表视图可见,&#39;第3年&#39;可以在自身内滚动,而不是整个线性布局本身。当我检查DDMS时,它显示滚动视图不可滚动。如果fillViewport为false,则LinearLayout中的所有列表视图都会缩小并成为一个高且可滚动的项目。我试图让我的列表完全展开,并且在溢出时,scrollview应滚动linearlayout而不是使列表视图中的各个项目滚动。有人能帮忙吗?

可在此处找到图片:http://i.stack.imgur.com/frU0P.png

在上面的屏幕截图中,fillViewPort = false,所有列表视图缩小为一个项目高,每个列表都可单独滚动,有3个列表视图。

这里是我的片段代码,为了简单起见,我已经用简单的字母数字加载了我的listview,动态添加listViews的方法是notifyCourseDataSetChange():

import java.io.IOException;
import java.util.ArrayList;

import org.holoeverywhere.widget.Toast;

import android.content.SharedPreferences;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.RelativeLayout;
import android.widget.ScrollView;
import android.widget.TextView;

import com.actionbarsherlock.app.SherlockFragment;
import com.example.u2.R;
import com.example.u2.constantsandprocesses.Course;
import com.example.u2.constantsandprocesses.DatabaseHelper;
import com.example.u2.constantsandprocesses.DegreeYear;
import com.example.u2.constantsandprocesses.ScienceDegreePlan;
import com.example.u2.constantsandprocesses.UCT_Constants;
import com.example.u2.constantsandprocesses.DegreePlan;

public class DegreePlannerStep2Fragment extends SherlockFragment {
    private LinearLayout baseLayout;
    private DatabaseHelper DBHelper;
    private String faculty;
    private String degree;
    private String degreeAbbrev;
    private String major1;
    private String major2;
    private DegreePlan plan;
    private TextView title;
    private View divider;
    private int facultyColour;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        SharedPreferences sp = getActivity().getSharedPreferences(UCT_Constants.PREFS_DEGREE, 0);
        faculty = sp.getString("faculty", null);
        degree = sp.getString("degree", null);
        degreeAbbrev = sp.getString("degreeAbbrev", null);
        major1 = sp.getString("major1", null);
        major2 = sp.getString("major2", null);
        setRetainInstance(true);
        if (savedInstanceState == null){
            DBHelper = new DatabaseHelper(getActivity());
            try {
                Log.d("DPS2", "connecting to db");
                DBHelper.connectDataBase();
            } catch (IOException e) {
                e.printStackTrace();
            }
            new GetAllCourses().execute(new String [] {major1, major2, faculty});
        }
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.degree_planner_step_2, container, false);
        if (faculty!=null){
            facultyColour = selectColour(faculty);
            baseLayout = (LinearLayout) view.findViewById(R.id.degreeplanner2_lin_layout);
            title = (TextView) view.findViewById(R.id.degree_planner_step2_title);
            title.setText(degree);
            divider = view.findViewById(R.id.degree_planner_divider);
            divider.setBackgroundResource(facultyColour);
        }
        return view;
    }

    @Override
    public void onPause() {
        super.onPause();
        DBHelper.close();
    }

    @Override
    public void onResume() {
        super.onResume();
        //open database connection
        try {
            Log.d("DPS2", "opening db");
            DBHelper.connectDataBase();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    /*
     * returns the id (int) of the colour variable for the faculty
     */
    private int selectColour(String facultyName) {
        String [] faculties = getActivity().getResources().getStringArray(R.array.faculties);
        if (facultyName.equals(faculties[0])){
            return R.color.Commerce;
        }else if(facultyName.equals(faculties[1])){
            return R.color.EBE;
        }else if(facultyName.equals(faculties[2])){
            return R.color.Health_Sciences;
        }else if(facultyName.equals(faculties[3])){
            return R.color.Humanities;
        }else if (facultyName.equals(faculties[4])){
            return R.color.Law;
        }else{
            return R.color.Science;
        }
    }

    public void notifyCourseDataSetChange(){
        for (DegreeYear dy : plan.getDegreeYears()){
            if (dy.isActive()){
                LayoutInflater inflater = getActivity().getLayoutInflater();
                View sectionHeader = inflater.inflate(R.layout.listview_section_header, null);
                ((TextView)sectionHeader.findViewById(R.id.section_header_title)).setText("Year "+dy.getYear());        //section header title
                sectionHeader.findViewById(R.id.section_header_divider).setBackgroundResource(facultyColour);   //section header divider
                ListView lv = new ListView(getActivity());
                lv.setHeaderDividersEnabled(false);
                lv.addHeaderView(sectionHeader);
                lv.setAdapter(new ArrayAdapter<String>(getActivity(), R.layout.drawer_list_item,new String [] {"a","b","c","d"}));
                baseLayout.addView(lv);
            }
        }
    }

    private class GetAllCourses extends AsyncTask<String, Void, ArrayList<Course>>{
        String facultyName = "";

        @Override
        protected ArrayList<Course> doInBackground(String... params) {
            facultyName = params[2];
            return DBHelper.getCoursesForMajor(params[0], params[1]);
        }

        @Override
        protected void onPostExecute(ArrayList<Course> result) {
            super.onPostExecute(result);
            String [] faculties = getActivity().getResources().getStringArray(R.array.faculties);
            if (facultyName.equals(faculties[0])){          //COM
                //TODO create corresponding degree
            }else if(facultyName.equals(faculties[1])){     //EBE
                //TODO create corresponding degree
            }else if(facultyName.equals(faculties[2])){     //Health
                //TODO create corresponding degree
            }else if(facultyName.equals(faculties[3])){     //HUM
                //TODO create corresponding degree
            }else if (facultyName.equals(faculties[4])){    //LAW
                //TODO create corresponding degree
            }else{                                          //SCI
                plan = new ScienceDegreePlan(result);
            }
            notifyCourseDataSetChange();
        }

    }
}

2 个答案:

答案 0 :(得分:1)

这里的问题是您在ScrollView中添加ListView。这是文档中的引用

  

你永远不应该使用带有ListView的ScrollView,因为ListView负责自己的垂直滚动。最重要的是,这样做会使ListView中的所有重要优化都无法处理大型列表,因为它有效地强制ListView显示其整个项目列表以填充ScrollView提供的无限容器。

因此,您只需添加没有ListView的项目。

答案 1 :(得分:0)

您可以改用RecyclerView。请注意,如果您确实使用它,则必须对适配器进行更改,因为RecyclerView需要RecyclerView.Adapter作为适配器。

this answer

它滚动并感觉就像ListView一样。

编辑:我忘了提及你需要确保在notifyDataSetChanged()运行时不要运行onBindViewHolder。它一直在循环中运行。或者您可以使用notifyItemInserted(int position)notifyItemRemoved(int position)通知适配器刷新它。 RecyclerViewnotifyItemInserted