Question

我有一个按钮（setButton），按下按钮后，我希望修改后的AutoCompleteTextView显示下拉菜单

我有两个班级

AutoCompleteTextViewTest1Activity.class

package com.autocompletetextviewtest1;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;


public class AutoCompleteTextViewTest1Activity extends Activity {
ArrayAdapter<String> adapter1;
ArrayAdapter<String> adapter2;
private InstantAutoComplete actv;
private String[] countries2 ={"Taiwan", "China", "S. Korea", "USA", "Japan", "Russia"};
private String[] countries={};
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);

adapter1 = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, countries);
adapter2 = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, countries2);
actv = (InstantAutoComplete)findViewById(R.id.actv);
actv.setAdapter(adapter1);

Button setButton = (Button)findViewById(R.id.setButton);
Button clearButton = (Button)findViewById(R.id.clearButton);

setButton.setOnClickListener(new OnClickListener(){
public void onClick(View v){
actv.setAdapter(adapter2);
actv.requestFocus();
}
});

clearButton.setOnClickListener(new OnClickListener(){
public void onClick(View v){
actv.setAdapter(adapter1);
        }
});
}
}

和

InstantAutoComplete.class

package com.autocompletetextviewtest1;

import android.content.Context;   
import android.graphics.Rect; 
import android.util.AttributeSet; 
import android.widget.AutoCompleteTextView; 

public class InstantAutoComplete extends AutoCompleteTextView { 

public InstantAutoComplete(Context context) { 
super(context); 
} 

public InstantAutoComplete(Context arg0, AttributeSet arg1) { 
super(arg0, arg1); 
} 

public InstantAutoComplete(Context arg0, AttributeSet arg1, int arg2) { 
super(arg0, arg1, arg2); 
} 

@Override 
public boolean enoughToFilter() { 
return true; 
} 

@Override 
protected void onFocusChanged(boolean focused, int direction, 
Rect previouslyFocusedRect) { 
super.onFocusChanged(focused, direction, previouslyFocusedRect); 
if (focused) { 
performFiltering(getText(), 0); 
showDropDown(); 

} 
} 

}

但是我的AutoCompleteTextView在按下setButton时没有显示下拉菜单。我能做什么？谢谢！

Answer 1

尝试在setButton onClick中调用actv.invalidate（）以使用新更新的适配器刷新视图。

Answer 2

这对我有用。请注意，我在适当的位置有日志，以检查我的webservice调用及其返回值。这对自动完成的工作至关重要。在您的情况下，您可能需要删除webservice调用并使用硬编码值自行填充适配器。

在onCreate中初始化

fromAutoComplete = new AutoComplete(this, R.layout.autocomplete_list_item);
fromAutoComplete.setNotifyOnChange(true);
fromAddress = (AutoCompleteTextView) findViewById(R.id.fromAddress);
fromAddress.setAdapter(fromAutoComplete);
fromAddress.setOnItemClickListener(this);

自动完成适配器，用于检查您的字符并反复调用Web服务，以显示在下拉列表中。

请注意，


此api需要一个google api密钥，您需要为自己生成密钥。也不要忘记为您的密钥启用Location API。没有它，不会工作。

将变量放在webservice调用中（出于某种疯狂的原因）。最后的传感器变量为我工作。随意从您的logcat上的提琴手或镀铬物上进行测试。

public AutoComplete(Context context, int textViewResourceId) {
    super(context, textViewResourceId);
}

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

@Override
public String getItem(int index) {
    return resultList.get(index);
}

@Override
public Filter getFilter() {
    Filter filter = new Filter() {
        @Override
        protected FilterResults performFiltering(CharSequence constraint) {
            FilterResults filterResults = new FilterResults();
            if (constraint != null) {
                // Retrieve the autocomplete results.
                resultList = autocomplete(constraint.toString());

                // Assign the data to the FilterResults
                filterResults.values = resultList;
                filterResults.count = resultList.size();
            }
            return filterResults;
        }

        @Override
        protected void publishResults(CharSequence constraint, FilterResults results) {
            if (results != null && results.count > 0) {
                notifyDataSetChanged();
            } else {
                notifyDataSetInvalidated();
            }
        }
    };
    return filter;
}

private ArrayList<String> autocomplete(String input) {
    ArrayList<String> resultList = null;

    HttpURLConnection conn = null;
    StringBuilder jsonResults = new StringBuilder();
    try {
        StringBuilder sb = new StringBuilder(PLACES_API_BASE + TYPE_AUTOCOMPLETE + OUT_JSON);
        sb.append("?key=" + API_KEY+"&sensor=false");
        sb.append("&components=country:in");
        sb.append("&input=" + URLEncoder.encode(input, "utf8"));
        Log.d(LOG_TAG, "Calling "+sb.toString()) ;

        URL url = new URL(sb.toString());
        conn = (HttpURLConnection) url.openConnection();
        InputStreamReader in = new InputStreamReader(conn.getInputStream());

        // Load the results into a StringBuilder
        int read;
        char[] buff = new char[1024];
        while ((read = in.read(buff)) != -1) {
            jsonResults.append(buff, 0, read);
        }
    } catch (MalformedURLException e) {
        Log.e(LOG_TAG, "Error processing Places API URL", e);
        return resultList;
    } catch (IOException e) {
        Log.e(LOG_TAG, "Error connecting to Places API", e);
        return resultList;
    } finally {
        if (conn != null) {
            conn.disconnect();
        }
    }

    try {
        // Create a JSON object hierarchy from the results
        JSONObject jsonObj = new JSONObject(jsonResults.toString());
        JSONArray predsJsonArray = jsonObj.getJSONArray("predictions");

        // Extract the Place descriptions from the results
        resultList = new ArrayList<String>(predsJsonArray.length());
        for (int i = 0; i < predsJsonArray.length(); i++) {
            resultList.add(predsJsonArray.getJSONObject(i).getString("description"));
        }
    } catch (JSONException e) {
        Log.e(LOG_TAG, "Cannot process JSON results", e);
    }

    Log.d(LOG_TAG, resultList.size() + " in total returned.") ;

    return resultList;
}

从下拉文本中选择项目

@Override
public void onItemClick(AdapterView<?> adapterView, View view, int position, long id) {
    Double latitude, longitude;
    ArrayList<String> resultList = null;
    HttpURLConnection conn = null;
    StringBuilder jsonResults = new StringBuilder();
    String str = (String) adapterView.getItemAtPosition(position);
    try {
        StringBuilder sb = new StringBuilder(
                "http://maps.googleapis.com/maps/api/geocode/json?" + "address="
                        + URLEncoder.encode(str, "utf-8") + "&sensor=true");

        URL url = new URL(sb.toString());
        Log.d("Taxeeta", url.toString() + " Called");
        conn = (HttpURLConnection) url.openConnection();
        InputStreamReader in = new InputStreamReader(conn.getInputStream());

        // Load the results into a StringBuilder
        int read;
        char[] buff = new char[1024];
        while ((read = in.read(buff)) != -1) {
            jsonResults.append(buff, 0, read);
        }
    } catch (MalformedURLException e) {
        Log.e("Taxeeta", "Error processing Places API URL", e);
    } catch (IOException e) {
        Log.e("Taxeeta", "Error connecting to Places API", e);
    } finally {
        if (conn != null) {
            conn.disconnect();
        }
    }

    try {
        // Create a JSON object hierarchy from the results
        JSONObject jsonObj = new JSONObject(jsonResults.toString());
        JSONObject location = ((JSONObject) jsonObj.getJSONArray("results").get(0))
                .getJSONObject("geometry").getJSONObject("location");
        latitude = location.optDouble("lat");
        longitude = location.optDouble("lng");
        Log.d("Taxeeta", "Received Latitude " + latitude + ": Longitude" + longitude);
        if (view.getId() == fromAddress.getId()) {
            source = new GeoPoint((int) (latitude * 1E6), (int) (longitude * 1E6));
            Log.d("Taxeeta", "Source Done");
        } else {
            destination = new GeoPoint((int) (latitude * 1E6), (int) (longitude * 1E6));
            Log.d("Taxeeta", "Destination Done");
        }
    } catch (JSONException e) {
        Log.e("Taxeeta", "Cannot process JSON results", e);
    }
}

AutoCompleteTextView不显示下拉列表

2 个答案: