如何在用数据加载列表视图之前在具有列表视图的活动中显示进度条?

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我有一个ListView在我的第二个activity.OnItemClick,我调用一个web服务,并试图获取数据。在此之后,我正在转向第三项活动,该活动也ListView对之前的活动ListView项目进行了描述。

我想在填充这个之前显示一个进度对话框ListView

我不明白该怎么做ListView?有人知道该怎么做吗?

我的代码 :

ThirdActivity.java

   package com.google.iprotect;

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

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import org.xmlpull.v1.XmlPullParserException;

import com.google.iprotect.layout.TitleBarLayout;

import android.app.Activity;
import android.app.ListActivity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.content.res.ColorStateList;
import android.content.res.XmlResourceParser;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.ProgressBar;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.TextView;

public class ThirdActivity extends ListActivity implements OnItemClickListener{

    JSONArray jArray1,jArray2;
    String one,two,three,tablename;
    String color,r;
    JSONObject responseJSON;
    TitleBarLayout titlebarLayout;
    final ArrayList<Tables> arraylist = new ArrayList<Tables>();
    TextView tableName;
    ColorStateList colorStateList1;
    String email1,password1;
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.thirdactivity);

        ListView lv=getListView();
        lv.setOnItemClickListener(this);


        tablename=getIntent().getExtras().getString("Table Name");
        email1 = getIntent().getExtras().getString("email");
        password1 =getIntent().getExtras().getString("password");

        titlebarLayout = new TitleBarLayout(ThirdActivity.this);
        titlebarLayout.setLeftButtonText("go Back");
        titlebarLayout.setRightButtonText("Logout");
        titlebarLayout.setTitle(tablename);
        titlebarLayout.setLeftButtonSize(70,40);
        titlebarLayout.setRightButtonSize(70,40);
        //titlebarLayout.setLeftButtonLeftDrawable(R.drawable.refresh);

        //titlebarLayout.setRightButtonLeftDrawable(R.drawable.buttonrefresh);
        //titlebarLayout.setLeftButtonBackgroundColor(Color.rgb(255,255,255));
        //titlebarLayout.setRightButtonBackgroundColor(Color.rgb(34,49,64));
        //titlebarLayout.setLeftButtonTextColor(Color.rgb(255,255,255));
        //titlebarLayout.setRightButtonTextColor(Color.rgb(255,255,0));     

        XmlResourceParser parser1 =getResources().getXml(R.color.colorstatelist);


        try {
            colorStateList1 = ColorStateList.createFromXml(getResources(), parser1);
            titlebarLayout.setRightButtonTextColor(colorStateList1);
        } catch (XmlPullParserException e) {    
            e.printStackTrace();
        } catch (IOException e) {

            e.printStackTrace();
        }

        OnClickListener listener = new OnClickListener() {

            public void onClick(View v) {
                // TODO Auto-generated method stub
                if (v.getId() == R.id.left_button) {
                    Intent intent = new Intent(ThirdActivity.this,SecondActivity.class);
                    intent.putExtra("email", email1);
                    intent.putExtra("password", password1);
                    startActivity(intent);
                    finish();

                } else if (v.getId() == R.id.right_button) {
                    Intent intent = new Intent(ThirdActivity.this,
                            MainActivity.class);
                    //intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                    intent.setFlags( Intent.FLAG_ACTIVITY_CLEAR_TASK | Intent.FLAG_ACTIVITY_NEW_TASK);
                    ThirdActivity.this.startActivity(intent);

                }
            }
        };
        titlebarLayout.setLeftButtonOnClickListener(listener);
        titlebarLayout.setRightButtonOnClickListener(listener);


        updateTableList();




    }

    private void updateTableList() {
        // TODO Auto-generated method stub
        //final ProgressDialog pd1=ProgressDialog.show(this, "Calling Webservice", "Waiting...", true, false);

        final ProgressBar pbHeaderProgress = (ProgressBar) findViewById(R.id.pbHeaderProgress);

        new AsyncTask<Void, Void, Void>() {


            protected void onPreExecute() {
                // TODO Auto-generated method stub
                super.onPreExecute();
                pbHeaderProgress.setVisibility(View.VISIBLE);
            }



            protected Void doInBackground(Void... params) {
                r = invokeWebService1(tablename);
                //pd1.dismiss();

                try {
                    responseJSON = new JSONObject(r);
                    //json reading
                    jArray1 = responseJSON.getJSONArray("FirstThree");//get JSONArray jArray1 from JSONObject with name FirstThree
                    jArray2 = responseJSON.getJSONArray("Color");//get JSONArray jArray2 from JSONOobject with name Color
                    JSONObject json_data1 = null;
                    JSONObject json_data2 = null;

                    for (int i = 0; i < jArray1.length(); i++) {
                        json_data1 = jArray1.getJSONObject(i);//get JSONObject json_data1 from JSONArray at index i;
                        one = json_data1.getString("One");//get value from JSONObject json_data1 with key "One"
                        two = json_data1.getString("Two");
                        three = json_data1.getString("Three");
                        json_data2 = jArray2.getJSONObject(i);
                        color = json_data2.getString("color");//get value from JSONObject json_data2 with key "color"

                        Tables tables = new Tables();
                        //set value to Tables Class
                        tables.column1 = one;
                        tables.column2 = two;
                        tables.column3 = three;
                        tables.tableName=tablename;
                        tables.color=color;
                        //add Tables object into ArrayList<Tables>
                        arraylist.add(tables);

                        Log.i("ONE", json_data1.getString("One"));
                        Log.i("TWO", json_data1.getString("Two"));
                        Log.i("THREE", json_data1.getString("Three"));
                        Log.i("color",""+ json_data2.getString("color"));
                    }

                } catch (JSONException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
                return null;
            }

            protected void onPostExecute(Void result) {
                pbHeaderProgress.setVisibility(View.GONE);

                //Custom Adapter for ListView
                TableDetailAdapter adaptor = new TableDetailAdapter(ThirdActivity.this,
                        R.layout.table_data_list_item, arraylist);
                setListAdapter(adaptor);
            }
        }.execute();

    }

    protected String invokeWebService1(String tablename2) {
        // TODO Auto-generated method stub
        String response = "";
        try {
            WebService webService = new WebService(
            "http://sphinx-solution.com/iProtect/api.php?");

            // Pass the parameters if needed
            Map<String, String> params = new HashMap<String, String>();
            params.put("action", "getTableRecords");
            params.put("tablename", tablename2);
            params.put("email", email1);
            params.put("password", password1);

            // Get JSON response from server the "" are where the method name
            // would normally go if needed example
            response = webService.WebGet("auth", params);

        } catch (Exception e) {
            Log.d("Error: ", e.getMessage());
        }
        return response;
    }


    public void onItemClick(AdapterView<?> arg0, View arg1, int position, long arg3) {
        // TODO Auto-generated method stub

        Log.v("", "Click ListItem Number "+position);
        Intent intent = new Intent(ThirdActivity.this,FourthActivity.class);
        intent.putExtra("Json", responseJSON.toString());//sending json Object as a string to next activity
        intent.putExtra("Table Name", tablename);
        intent.putExtra("email", email1);
        intent.putExtra("password", password1);
        intent.putExtra("Item No", position);
        startActivity(intent);

    }

}

thirdactivity.xml

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

    <include
        android:id="@+id/titlebar"
        layout="@layout/titlebar_layout" />

    <ProgressBar
        android:id="@+id/pbHeaderProgress"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_weight="2" >
    </ProgressBar>

    <ListView
        android:id="@android:id/list"
        android:layout_width="match_parent"
        android:layout_height="260dp" 
        android:layout_weight="5.04">
    </ListView>

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="@dimen/titlebar_height"
        android:layout_alignParentBottom="true"
        android:background="@color/footer_bg_color"
        android:gravity="bottom"
        android:orientation="horizontal" >

        <include
            android:id="@+id/footer"
            android:layout_height="@dimen/titlebar_height"
            android:layout_gravity="bottom|center_horizontal"
            layout="@layout/footer_layout" />
    </LinearLayout>

</LinearLayout>
提问于
用户回答回答于

有几种方法在加载时显示进度条(圆圈)activity。在你的情况下,一个与ListView它在一起。

如果你使用的是ActionBar,你可以这样调用ProgressBar(这可能会在你的onCreate()

requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS);  
setProgressBarIndeterminateVisibility(true);

在完成列表显示后,隐藏它:

setProgressBarIndeterminateVisibility(false);

在布局中(XML),代码如下:

<LinearLayout
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:layout_weight="1"
    android:orientation="vertical" >

    <LinearLayout
        android:id="@+id/linlaHeaderProgress"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:gravity="center"
        android:orientation="vertical"
        android:visibility="gone" >

        <ProgressBar
            android:id="@+id/pbHeaderProgress"
            android:style="@style/Spinner"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content" >
        </ProgressBar>
    </LinearLayout>

    <ListView
        android:id="@+id/list"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:layout_weight="1"
        android:cacheColorHint="@android:color/transparent"
        android:divider="#00000000"
        android:dividerHeight="0dp"
        android:fadingEdge="none"
        android:persistentDrawingCache="scrolling"
        android:smoothScrollbar="false" >
    </ListView>
</LinearLayout>

我使用AsyncTask为我的列表获取数据。所以,在AsyncTask中,onPreExecute()代码:

// CAST THE LINEARLAYOUT HOLDING THE MAIN PROGRESS (SPINNER)
LinearLayout linlaHeaderProgress = (LinearLayout) findViewById(R.id.linlaHeaderProgress);

@Override
protected void onPreExecute() {    
    // SHOW THE SPINNER WHILE LOADING FEEDS
    linlaHeaderProgress.setVisibility(View.VISIBLE);
}

并在将onPostExecute()适配器设置为ListView

@Override
protected void onPostExecute(Void result) {     
    // SET THE ADAPTER TO THE LISTVIEW
    lv.setAdapter(adapter);

    // CHANGE THE LOADINGMORE STATUS TO PERMIT FETCHING MORE DATA
    loadingMore = false;

    // HIDE THE SPINNER AFTER LOADING FEEDS
    linlaHeaderProgress.setVisibility(View.GONE);
}

这是它在加载其中一个时在我的应用程序中的外观 :

用户回答回答于

参考:http//www.tutorialspoint.com/android/android_loading_spinner.htm

布局:

<ProgressBar
   android:id="@+id/progressBar1"
   style="?android:attr/progressBarStyleLarge"
   android:layout_width="wrap_content"
   android:layout_height="wrap_content"
   android:layout_centerHorizontal="true" />

在xml中定义之后,你必须通过ProgressBar类在java文件中获取其引用。其语法如下:

private ProgressBar spinner;
spinner = (ProgressBar)findViewById(R.id.progressBar1);

之后,可以使其消失,并在需要时通过setVisibility方法将其恢复。其语法如下:

spinner.setVisibility(View.GONE);
spinner.setVisibility(View.VISIBLE);

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