Question

我有登录的登录页面，如果用户点击登录按钮，它将转到tabactivity。在标签活动中，我有四个选项卡：主页，库存等。从tabactivity我调用嵌套活动的活动组。从活动组我称之为家庭活动。从家里我加载标签栏并调用webservices并解析值并在home选项卡中加载主页活动。这需要时间。我该如何避免黑屏？谁能举个例子？我已经尝试了很多，但它没有用。如果有人知道，请给出代码。在第二个活动中，我将标签栏加载到加载的标签并调用webservices。我必须展示一些启动画面。

我在doInBackground方法中添加了tabbar，这是正确的吗？

import java.util.ArrayList;

//import com.inquest.LoginActivity.FetchTask;

import android.app.Activity;
import android.app.AlertDialog;
import android.app.ProgressDialog;
import android.app.TabActivity;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.res.Resources;
import android.graphics.Typeface;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.Gravity;
import android.view.Window;
import android.widget.Button;
import android.widget.RelativeLayout;
import android.widget.TabHost;
import android.widget.TabWidget;
import android.widget.TextView;
import android.widget.TabHost.TabSpec;
//TabActivity 

public class HelloTabWidget extends TabActivity 
{
     int width =40;  
     int height =49;
    //private TabHost tabHost;
    TextView txthome;
    TextView txtstock;
    TextView txtcitn;
    TextView txtmyquest;
    Button btn;
    //private ProgressDialog pd = null; 
    private ProgressDialog dlg; 
    private Object data = null; 
    String strusername="";
    String strPassWord="";
    String questGroupId="";
    String userid="";
    String systemuserid="";
    String providerid="";
    private ProgressDialog dialog; 
 public void onCreate(Bundle savedInstanceState) { 
       super.onCreate(savedInstanceState); 
       requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS); 
       setProgressBarIndeterminateVisibility(true);
    setContentView(R.layout.tab); 






    new TabTask(HelloTabWidget.this).execute(null);

 //}

 }





 public class TabTask extends AsyncTask<Void, Void,Void> 
 { 
        private ProgressDialog dlg; 
          private Context ctx; 
        public TabTask(Context context) { 
            ctx = context; 
        } 




        @Override 
        protected void onPreExecute() { 
            super.onPreExecute(); 
            dlg = new ProgressDialog(HelloTabWidget.this); 
            dlg.setMessage("Loading...."); 
            dlg.show();
        } 



        @Override
        protected Void doInBackground(Void... params) {
            // TODO Auto-generated method stub
            try
            {
                 TabHost.TabSpec spec;
                 TabHost tabHost=getTabHost();
                 TabWidget tabWidget = tabHost.getTabWidget();
                Resources res = getResources();

                                                    Typeface myTypeface = Typeface.createFromAsset(ctx.getAssets(),"verdanab.TTF");
                Typeface myTypeface1 = Typeface.createFromAsset(ctx.getAssets(),"verdana.TTF");
                Intent homeintent;   
                // Create an Intent to launch an Activity for the tab (to be reused) 
                homeintent = new Intent();
                 Bundle bundle=getIntent().getExtras();
                 String strusername=bundle.get("strUserName").toString();
                 String strPassWord=bundle.get("strPassword").toString();
                 String questGroupId=bundle.get("questGroupId").toString();
                 String userid=bundle.get("userid").toString();
                 String systemuserid=bundle.get("systemuserid").toString();
                 String providerid=bundle.get("providerid").toString();
                  Log.d("home activity username", strusername);
                 Log.d("home activity password", strPassWord);
                 Log.d("home activityquestGroupId",questGroupId);
                    homeintent.setClass(ctx, HomeActivityGroup.class); 
                  homeintent.putExtra("strUserName", strusername);
                  homeintent.putExtra("strPassWord",strPassWord );
                  homeintent.putExtra("questGroupId",questGroupId);
                  homeintent.putExtra("userid",userid);
                  homeintent.putExtra("systemuserid", systemuserid);
                  homeintent.putExtra("checking", "one");

                   spec = tabHost.newTabSpec("home").setIndicator("Home",res.getDrawable(R.drawable.home_tab_bar_icon)).setContent(homeintent);
                tabHost.addTab(spec); 

                //homeintent = new Intent().setClass(this,ThemeSearchActivity.class); 
                homeintent = new Intent().setClass(ctx,StockActivity.class);
                homeintent.putExtra("strUserName", strusername);
                homeintent.putExtra("strPassWord",strPassWord );
                homeintent.putExtra("questGroupId",questGroupId);
                homeintent.putExtra("userid",userid);
                homeintent.putExtra("systemuserid", systemuserid);
                homeintent.putExtra("providerid", providerid);  
                spec = tabHost.newTabSpec("stock").setIndicator("Stock",res.getDrawable(R.drawable.stocks_tab_bar_icon)).setContent(homeintent);
                tabHost.addTab(spec);
                homeintent = new Intent().setClass(ctx,ArticleActivity.class); 
                   spec = tabHost.newTabSpec("citn").setIndicator("CITN",res.getDrawable(R.drawable.citn_tabbar_icon)).setContent(homeintent);
                tabHost.addTab(spec);
                homeintent = new Intent().setClass(ctx, MyCompaniesActivity.class); 
                spec = tabHost.newTabSpec("myquest").setIndicator("My Quest",res.getDrawable(R.drawable.quest_tab_bar_icon)).setContent(homeintent);
                tabHost.addTab(spec);

                for (int i =0; i < tabWidget.getChildCount(); i++) {
                     //tabWidget.getChildAt(i).setBackgroundColor(R.color.black);
                      tabWidget.getChildAt(i).getLayoutParams().height = height;
               tabWidget.getChildAt(i).getLayoutParams().width = width;
               RelativeLayout relLayout = (RelativeLayout)tabWidget.getChildAt(i); 
               TextView tv = (TextView)relLayout.getChildAt(1); 
               tv.setTextSize(10.0f);
               //tv.setCompoundDrawablesWithIntrinsicBounds(0, 1, 0, 0);
              tv.setTypeface(myTypeface1);          



            }
            }
                catch (Exception e) {
                // TODO: handle exception
                    e.printStackTrace();
            }

            return null;
        }

    }   


}

Answer 1

您需要在Tabbar活动中实施 AsyncTask 功能。

private class LongOperation extends AsyncTask<String, Void, String> {

@Override
    protected void onPreExecute() {
    // Things to be done before execution of long running operation. For example showing ProgessDialog
    }

    @Override
    protected String doInBackground(String... params) {
        // perform long running operation operation
        return null;
    }

    @Override
    protected void onPostExecute(String result) {
        // execution of result of Long time consuming operation
    }

    @Override
    protected void onProgressUpdate(Void... values) {
      // Things to be done while execution of long running operation is in progress. For example updating ProgessDialog
     }
}

Answer 2

我也有同样的问题，但我的问题是通过将此属性添加到活动来解决的：

[Activity(Theme = "@android:style/Theme.Translucent.NoTitleBar")]

试试吧。

Answer 3

这很简单只是不要在onCreate（）方法中调用任何长时间运行的任务，它会阻止你的活动创建，直到任务完成。

只需在此方法下定义UI任务，并从onStart（）或onResume（）方法调用任何其他调用。

尽量保持你的oncreate（）方法精简版。

显示黑屏，从一个活动到另一个活动几分钟

3 个答案: