如何向Android应用添加搜索功能?

时间:2019-03-18 06:10:57

标签: android

我想向我的android跟踪器应用程序添加搜索功能,以便用户可以在列表视图中搜索特定位置。我的代码已在地图上绘制了所有详细信息,我只想搜索特定地点并获取地震信息。

MainActivity.java

package com.vuvucall.maptest;

import android.app.ProgressDialog;
import android.content.Context;
import android.os.AsyncTask;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.FrameLayout;

import com.google.android.gms.maps.CameraUpdate;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.LatLngBounds;
import com.google.android.gms.maps.model.MarkerOptions;

import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import org.xmlpull.v1.XmlPullParserFactory;

import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;

public class MainActivity extends AppCompatActivity implements OnMapReadyCallback {

    SupportMapFragment mapFragment;
    GoogleMap googleMap;
    ArrayList<Item> mItems = new ArrayList<>();
    FrameLayout mapsLayout;
    Button loadDataButton;
    boolean listLoad = true;
    LinearLayoutManager linearLayoutManager;
    RecyclerView recycleView;
    ListDataAdapter listDataAdapter;
    private Context context;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        context = this;

        linearLayoutManager = new LinearLayoutManager(context);


        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        mapsLayout = (FrameLayout) findViewById(R.id.mapsLayout);
        loadDataButton = (Button) findViewById(R.id.loadDataButton);
        recycleView = (RecyclerView) findViewById(R.id.recycleView);
        recycleView.setLayoutManager(linearLayoutManager);


        mapFragment = (SupportMapFragment) getSupportFragmentManager()
                .findFragmentById(R.id.map);
        mapFragment.getMapAsync(this);


        loadDataButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                if (listLoad) {
                    listLoad = false;
                    mapsLayout.setVisibility(View.VISIBLE);
                    recycleView.setVisibility(View.GONE);
                    loadMapsData(mItems);
                    loadDataButton.setText(getString(R.string.show_list));

                } else {
                    listLoad = true;
                    mapsLayout.setVisibility(View.GONE);
                    recycleView.setVisibility(View.VISIBLE);
                    loadListData(mItems);
                    loadDataButton.setText(getString(R.string.show_maps));
                }

            }
        });

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        //  getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
//        int id = item.getItemId();
//
//        //noinspection SimplifiableIfStatement
//        if (id == R.id.action_settings) {
//            return true;
//        }

        return super.onOptionsItemSelected(item);
    }

    @Override
    public void onMapReady(GoogleMap googleMap) {

        this.googleMap = googleMap;

        new ProcessInBackground().execute();


    }


    public class ProcessInBackground extends AsyncTask<Integer, Void, ArrayList<Item>> {
        ProgressDialog progressDialog = new ProgressDialog(MainActivity.this);

        Exception exception = null;

        @Override
        protected void onPreExecute() {
            super.onPreExecute();

            progressDialog.setMessage("Busy loading rss feed...please wait...");
            progressDialog.show();
        }

        @Override
        protected ArrayList<Item> doInBackground(Integer... params) {

            try {
                URL url = new URL("http://quakes.bgs.ac.uk/feeds/MhSeismology.xml");

                //creates new instance of PullParserFactory that can be used to create XML pull parsers
                XmlPullParserFactory factory = XmlPullParserFactory.newInstance();

                //Specifies whether the parser produced by this factory will provide support
                //for XML namespaces
                factory.setNamespaceAware(false);

                //creates a new instance of a XML pull parser using the currently configured
                //factory features
                XmlPullParser xpp = factory.newPullParser();

                // We will get the XML from an input stream
                xpp.setInput(getInputStream(url), "UTF_8");

                /* We will parse the XML content looking for the "<title>" tag which appears inside the "<item>" tag.
                 * We should take into consideration that the rss feed name is also enclosed in a "<title>" tag.
                 * Every feed begins with these lines: "<channel><title>Feed_Name</title> etc."
                 * We should skip the "<title>" tag which is a child of "<channel>" tag,
                 * and take into consideration only the "<title>" tag which is a child of the "<item>" tag
                 *
                 * In order to achieve this, we will make use of a boolean variable called "insideItem".
                 */
                boolean insideItem = false;

                // Returns the type of current event: START_TAG, END_TAG, START_DOCUMENT, END_DOCUMENT etc..
                int eventType = xpp.getEventType(); //loop control variable

                Item item = null;
                while (eventType != XmlPullParser.END_DOCUMENT) {
                    //if we are at a START_TAG (opening tag)
                    if (eventType == XmlPullParser.START_TAG) {
                        //if the tag is called "item"
                        if (xpp.getName().equalsIgnoreCase("item")) {
                            insideItem = true;
                            item = new Item();
                        }
                        //if the tag is called "title"
                        else if (xpp.getName().equalsIgnoreCase("title")) {
                            if (insideItem) {
                                // extract the text between <title> and </title>
                                item.setTitle(xpp.nextText());
                            }
                        }
                        //if the tag is called "link"
                        else if (xpp.getName().equalsIgnoreCase("link")) {
                            if (insideItem) {
                                // extract the text between <link> and </link>
                                item.setLink(xpp.nextText());
                            }
                        } else if (xpp.getName().equalsIgnoreCase("geo:lat")) {
                            if (insideItem) {
                                //extract the text between <geo:lat> and </geo:lat>
                                item.setLat(Double.valueOf(xpp.nextText()));
                            }
                        } else if (xpp.getName().equalsIgnoreCase("geo:long")) {
                            if (insideItem) {
                                //extract the text between <geo:lat> and </geo:lat>
                                item.setLon(Double.valueOf(xpp.nextText()));
                            }
                        }
                    }
                    //if we are at an END_TAG and the END_TAG is called "item"
                    else if (eventType == XmlPullParser.END_TAG && xpp.getName().equalsIgnoreCase("item")) {
                        insideItem = false;
                        mItems.add(item);
                    }

                    eventType = xpp.next(); //move to next element
                }

            } catch (MalformedURLException e) {
                exception = e;
            } catch (XmlPullParserException e) {
                exception = e;
            } catch (IOException e) {
                exception = e;
            }

            return mItems;
        }

        @Override
        protected void onPostExecute(ArrayList<Item> s) {
            super.onPostExecute(s);


            // ArrayAdapter<Item> adapter = new ArrayAdapter<>(MainActivity.this, android.R.layout.simple_list_item_1, mItems);
            // lvRss.setAdapter(adapter);

            progressDialog.dismiss();
            loadDataButton.setVisibility(View.VISIBLE);
            loadListData(s);
        }
    }

    public InputStream getInputStream(URL url) {
        try {
            //openConnection() returns instance that represents a connection to the remote object referred to by the URL
            //getInputStream() returns a stream that reads from the open connection
            return url.openConnection().getInputStream();
        } catch (IOException e) {
            return null;
        }
    }

    private void loadMapsData(ArrayList<Item> listData) {

        int i = 0;

        for (Item item : listData) {

            if (i % 5 == 0) {
                googleMap.addMarker(new MarkerOptions()
                        .position(new LatLng(item.getLat(), item.getLon()))
                        .title(item.getTitle())
                        .icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_GREEN)));
            } else if (i % 5 == 1) {
                googleMap.addMarker(new MarkerOptions()
                        .position(new LatLng(item.getLat(), item.getLon()))
                        .title(item.getTitle())
                        .icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_RED)));
            } else if (i % 5 == 2) {
                googleMap.addMarker(new MarkerOptions()
                        .position(new LatLng(item.getLat(), item.getLon()))
                        .title(item.getTitle())
                        .icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_YELLOW)));
            } else if (i % 5 == 3) {
                googleMap.addMarker(new MarkerOptions()
                        .position(new LatLng(item.getLat(), item.getLon()))
                        .title(item.getTitle())
                        .icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_ORANGE)));
            } else if (i % 5 == 4) {
                googleMap.addMarker(new MarkerOptions()
                        .position(new LatLng(item.getLat(), item.getLon()))
                        .title(item.getTitle())
                        .icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_VIOLET)));
            }

            i++;



        }


        LatLngBounds.Builder builder = new LatLngBounds.Builder();

        //the include method will calculate the min and max bound.
        for (Item item : listData) {
            builder.include(new LatLng(item.getLat(), item.getLon()));
        }


        LatLngBounds bounds = builder.build();

        int width = getResources().getDisplayMetrics().widthPixels;
        int height = getResources().getDisplayMetrics().heightPixels;
        int padding = (int) (width * 0.10); // offset from edges of the map 10% of screen

        CameraUpdate cu = CameraUpdateFactory.newLatLngBounds(bounds, width, height, padding);

        googleMap.animateCamera(cu);
    }

    private void loadListData(ArrayList<Item> listData) {
        listDataAdapter = new ListDataAdapter(context, listData);
        recycleView.setAdapter(listDataAdapter);
    }

}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:context=".MainActivity">

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        android:background="?attr/colorPrimary"
        app:popupTheme="@style/AppTheme.PopupOverlay" >

        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

            <Button
                android:visibility="gone"
                android:layout_alignParentRight="true"
                android:text="@string/show_maps"
                android:id="@+id/loadDataButton"
                android:layout_centerVertical="true"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content" />
        </RelativeLayout>

    </android.support.v7.widget.Toolbar>

    <include android:layout_width="match_parent" android:layout_height="match_parent" android:layout_below="@id/toolbar" layout="@layout/content_main" />

    <android.support.design.widget.FloatingActionButton
        android:id="@+id/fab"
        android:visibility="gone"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom|end"
        android:layout_margin="16dp"
        android:src="@android:drawable/ic_dialog_info" />

</RelativeLayout>

新问题

errors

errors

more errors

1 个答案:

答案 0 :(得分:1)

执行此操作的方法太多,但是我认为这是执行此操作的最简单方法...

首先在xml文件中创建一个Edittext 然后通过findViewbyid()在您的主要活动中找到它; 之后,在“主要活动”中添加以下行.....

editText.addTextChangedListener(new TextWatcher() {
        @Override
        public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
        }
        @Override
        public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {
        }
        @Override
        public void afterTextChanged(Editable editable)
        {
            filter(editable.toString());
        }
    }); 

现在使用filter方法。...在关闭onCreate方法之后将此方法放入您的活动类中。

private void filter(String text) {
ArrayList<String> filterdNames = new ArrayList<>();
for (String s : yourList) {
     if (s.toLowerCase().contains(text.toLowerCase())) {
        filterdNames.add(s);
    }
}
    final ArrayAdapter adap=new ArrayAdapter(this,android.R.layout.simple_list_item_1,filterdNames);
    lv.setAdapter(adap);
    lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            String text=adap.getItem(position).toString();
            int position=yourlist.indexOf(text); 
        }
    });

请询问您是否对此有任何疑问: