如何在搜索過程中更新列表視圖

Question

這是我啟動時的應用程序：

當我單擊列表視圖中的一項時，它將打開一個新活動並顯示一些數據。

當我搜索某些東西時，它看起來像這樣：

當我單擊列表中的一個項目時，它將啟動一個新活動。 但是開始的活動並不准確。

這是我的代碼：

HomeActivity.class

package com.thesis.herbalmedicines.activity;

import java.util.ArrayList;
import java.util.Arrays;

import android.app.Activity;
import android.content.Intent;
import android.content.res.TypedArray;
import android.graphics.Color;
import android.graphics.drawable.ColorDrawable;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.SearchView;
import android.widget.TextView;
import android.widget.Toast;

public class HomeActivity extends BaseActivity implements
        SearchView.OnQueryTextListener {

    ListView lv;
    SearchView search;

    String[] herb_names, sample_arr; //= ["Boils","",""];//, iso_codes;
    TypedArray herb_pics;

    ArrayList<Home> homelist;
    HomeAdapter adapter;



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

        getLayoutInflater().inflate(R.layout.home_layout, frameLayout);

        mDrawerList.setItemChecked(position, true);
        setTitle(listArray[position]);

        android.app.ActionBar ab = getActionBar(); 
        ColorDrawable colorDrawable = new ColorDrawable(Color.parseColor("#50B222"));     
        ab.setBackgroundDrawable(colorDrawable);


        lv = (ListView) findViewById(R.id.list_view);
        search = (SearchView) findViewById(R.id.search_view);

        herb_names = getResources().getStringArray(R.array.herb_names);
        //iso_codes = getResources().getStringArray(R.array.iso_Code);
        herb_pics = getResources().obtainTypedArray(R.array.herb_pics);

        homelist = new ArrayList<Home>();
        for (int i = 0; i < herb_names.length; i++) {
            Home home = new Home(herb_names[i], //iso_codes[i],
                    herb_pics.getResourceId(i, -1));
            homelist.add(home);
        }

        adapter = new HomeAdapter(getApplicationContext(), homelist);
        lv.setAdapter(adapter);

        lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            public void onItemClick(AdapterView<?> parent, View view,
                                    int position, long id) {

                if (position == 0) {
                    Intent a = new Intent(HomeActivity.this, Boils.class);
                    startActivity(a);

                    /** Fading Transition Effect */
                    HomeActivity.this.overridePendingTransition(android.R.anim.fade_in, android.R.anim.fade_out);
                }

                else if (position == 1) {
                    Intent b = new Intent(HomeActivity.this, Cystitis.class);
                    startActivity(b);

                    /** Fading Transition Effect */
                    HomeActivity.this.overridePendingTransition(android.R.anim.fade_in, android.R.anim.fade_out);
                }

                else if (position == 2) {
                    Intent c = new Intent(HomeActivity.this, Asthma.class);
                    startActivity(c);

                    /** Fading Transition Effect */
                    HomeActivity.this.overridePendingTransition(android.R.anim.fade_in, android.R.anim.fade_out);
                }
                else if (position == 3) {
                    Intent d = new Intent(HomeActivity.this, Feet.class);
                    startActivity(d);

                    /** Fading Transition Effect */
                    HomeActivity.this.overridePendingTransition(android.R.anim.fade_in, android.R.anim.fade_out);
                }



            }
        });
        search.setOnQueryTextListener(this);
    }

    @Override
    public boolean onQueryTextChange(String newText) {
        adapter.getFilter().filter(newText);
        return false;
    }

    @Override
    public boolean onQueryTextSubmit(String query) {
        return false;
    }



}

家.java

package com.thesis.herbalmedicines.activity;

public class Home {

    String name;
    int pics;
    Home(String name, int pics) {
        this.name = name;
        this.pics = pics;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getPics() {
        return pics;
    }

    public void setPics(int pics) {
        this.pics = pics;
    }

}

HomeAdapter.java

package com.thesis.herbalmedicines.activity;

import java.util.ArrayList;

import android.app.Activity;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Filter;
import android.widget.Filterable;
import android.widget.ImageView;
import android.widget.TextView;

public class HomeAdapter extends BaseAdapter implements Filterable {

    Context context;
    ArrayList<Home> homelist;
    ArrayList<Home> mStringFilterList;
    ValueFilter valueFilter;

    HomeAdapter(Context context, ArrayList<Home> homelist) {
        this.context = context;
        this.homelist = homelist;
        mStringFilterList = homelist;
    }

    @Override
    public int getCount() {
        return homelist.size();
    }

    @Override
    public Object getItem(int position) {
        return homelist.get(position);
    }

    @Override
    public long getItemId(int position) {
        return homelist.indexOf(getItem(position));
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {

        LayoutInflater mInflater = (LayoutInflater) context
                .getSystemService(Activity.LAYOUT_INFLATER_SERVICE);

        convertView = null;
        if (convertView == null) {
            convertView = mInflater.inflate(R.layout.list_item, null);

            TextView name_tv = (TextView) convertView.findViewById(R.id.name);
            ImageView iv = (ImageView) convertView.findViewById(R.id.pic);

            Home home = homelist.get(position);

            name_tv.setText(home.getName());
            iv.setImageResource(home.getPics());
        }
        return convertView;
    }

    @Override
    public Filter getFilter() {
        if (valueFilter == null) {
            valueFilter = new ValueFilter();
        }
        return valueFilter;
    }

    private class ValueFilter extends Filter {
        @Override
        protected FilterResults performFiltering(CharSequence constraint) {
            FilterResults results = new FilterResults();

            if (constraint != null && constraint.length() > 0) {
                ArrayList<Home> filterList = new ArrayList<Home>();
                for (int i = 0; i < mStringFilterList.size(); i++) {
                    if ((mStringFilterList.get(i).getName().toUpperCase())
                            .contains(constraint.toString().toUpperCase())) {

                        Home home = new Home(mStringFilterList.get(i)
                                .getName(), mStringFilterList.get(i)
                                .getPics());

                        filterList.add(home);
                    }
                }
                results.count = filterList.size();
                results.values = filterList;
            } else {
                results.count = mStringFilterList.size();
                results.values = mStringFilterList;
            }
            return results;

        }

        @SuppressWarnings("unchecked")
        @Override
        protected void publishResults(CharSequence constraint,
                FilterResults results) {
            homelist = (ArrayList<Home>) results.values;
            notifyDataSetChanged();
        }

    }

}

Answer 1

在每個onSerch上將adpter設置為listview

Answer 2

為什么要使用位置導航到其他活動？

    lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        public void onItemClick(AdapterView<?> parent, View view,
                                int position, long id) {

            if (position == 0) {
                Intent a = new Intent(HomeActivity.this, Boils.class);
                startActivity(a);

                /** Fading Transition Effect */
                HomeActivity.this.overridePendingTransition(android.R.anim.fade_in, android.R.anim.fade_out);
            }

            else if (position == 1) {
                Intent b = new Intent(HomeActivity.this, Cystitis.class);
                startActivity(b);

                /** Fading Transition Effect */
                HomeActivity.this.overridePendingTransition(android.R.anim.fade_in, android.R.anim.fade_out);
            }

            else if (position == 2) {
                Intent c = new Intent(HomeActivity.this, Asthma.class);
                startActivity(c);

                /** Fading Transition Effect */
                HomeActivity.this.overridePendingTransition(android.R.anim.fade_in, android.R.anim.fade_out);
            }
            else if (position == 3) {
                Intent d = new Intent(HomeActivity.this, Feet.class);
                startActivity(d);

                /** Fading Transition Effect */
                HomeActivity.this.overridePendingTransition(android.R.anim.fade_in, android.R.anim.fade_out);
            }



        }
    });
    search.setOnQueryTextListener(this);
}

每當適配器從搜索結果中刷新時，這將始終重置您的位置。

為了更好地做到這一點。 只需按照以下步驟在適配器中創建自定義偵聽器即可。

Public interface ListViewClick{
  void onListClick(Object type)
}

在活動中注冊您的接收器並傳遞活動類型以從適配器啟動

  private ListViewClick callback;
  HomeAdapter(Context context, ArrayList<Home> homelist,ListViewClick callback) {
        this.context = context;
        this.homelist = homelist;
        mStringFilterList = homelist;
        this.callback = callback;
    }

並在convertView點擊偵聽器上傳遞callback.onListClick(//type of activity to launch) 。

只需參考“家庭實體發起的活動類型”即可。 因此，您可以在單擊列表視圖的特定行時識別出將啟動哪個活動。

Answer 3

添加一個字段，該字段包含要在Home類中加載的類。 （ id字段是可選的）

public class Home {
    int id;
    String name;
    int pics;
    Class clazz;

    Home(int id, String name, int pics, Class clazz) {
        this.id = id;
        this.name = name;
        this.pics = pics;
        this.clazz = clazz;
    }
    // getters and setters
}

在初始化homelist添加id ，

// the classed to load
Class[] classes = {
    Boils.class,
    Cystitis.class,
    Asthma.class,
    Feet.class
};

for (int i = 0; i < herb_names.length; i++) {
    Home home = new Home(i, herb_names[i], herb_pics.getResourceId(i, -1), classes[i]);
    homelist.add(home);
}

在setOnItemClickListener內部，

lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
    public void onItemClick(AdapterView<?> parent, View view,  int position, long id) {

        Home item = (Home) adapter.getItem(position);

        Intent d = new Intent(HomeActivity.this, item.getClazz());
        startActivity(d);

        /** Fading Transition Effect */
        HomeActivity.this.overridePendingTransition(android.R.anim.fade_in, android.R.anim.fade_out);
    }
});

適配器也應進行幾處更改。

在getView內部，您將convertView強制為null。 這對性能不利。 （也考慮使用ViewHolder ）

@Override
public View getView(int position, View convertView, ViewGroup parent) {

    LayoutInflater mInflater = (LayoutInflater) context.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);

    if (convertView == null) {
        convertView = mInflater.inflate(R.layout.list_item, null);
    }

    TextView name_tv = (TextView) convertView.findViewById(R.id.name);
    ImageView iv = (ImageView) convertView.findViewById(R.id.pic);

    Home home = homelist.get(position);

    name_tv.setText(home.getName());
    iv.setImageResource(home.getPics());

    return convertView;
}

在publishResults內部，您將為數據集創建一個新引用。 您應該更新現有數據集。

@Override
protected void publishResults(CharSequence constraint,  FilterResults results) {
    homelist.clear();
    homelist.addAll((ArrayList<Home>) results.values);
    notifyDataSetChanged();
}