2

当在设置的开发人员选项进度对话框中选择“不保留活动”时，不会关闭。实际上，我正在显示 Progerss 栏，用于初始化应用程序，当我从 Activity A 到 Activity B 然后来到 Activity A 时，初始化完成后进度栏不会消失。下面是我的代码，

第一个活动

package com.example.donotkeepactivitiesalive;

import android.app.Activity;
import android.app.Dialog;
import android.app.ProgressDialog;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class MainActivity extends Activity {

    public static final int MESSAGE_PROGRESS_BAR_INITIALIZING = 1;
    private Dialog m_cObjDialog;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        System.out.println(getClass().getName() + "before InitializeEnvironment >>>>>>");
        new InitializeEnvironment().execute();
        System.out.println(getClass().getName() + "after InitializeEnvironment >>>>>>");
        Button lb = (Button) findViewById(R.id.button1);
        lb.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent lIntent = new Intent(MainActivity.this, SecondActivity.class);
                startActivity(lIntent);
            }
        });
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.activity_main, menu);
        return true;
    }

    @Override
    protected Dialog onCreateDialog(int id) {
        m_cObjDialog = new ProgressDialog(this);
        m_cObjDialog.setTitle("Initializing");
        ((ProgressDialog) m_cObjDialog).setMessage("Initializing the Application");
        m_cObjDialog.setCancelable(false);
        return m_cObjDialog;
    }


    class InitializeEnvironment extends AsyncTask<String, String, String> {
        @Override
        protected void onPreExecute() {
            System.out.println(getClass().getName() + "onPreExecute >>>>>>");
            super.onPreExecute();
            showDialog(MESSAGE_PROGRESS_BAR_INITIALIZING);
        }

        @Override
        protected String doInBackground(String... aurl) {
            System.out.println(getClass().getName() + " doInBackground >>>>>>");
            return null;
        }

        @Override
        protected void onPostExecute(String unused) {
            dismissDialog(MESSAGE_PROGRESS_BAR_INITIALIZING);
            System.out.println(getClass().getName() + " onPostExecute >>>>>>");
        }
    }

}

第二次活动

package com.example.donotkeepactivitiesalive;

import android.app.Activity;
import android.os.Bundle;

public class SecondActivity extends Activity{
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

}

即使启用了“不保留活动”，是否有任何方法可以跟踪此问题并正常工作

4

1 回答 1

0

我解决了这个问题，通过检查 Bundle 对象是否为空。如果 Bundle 对象为空，则调用 AsynTask 类，否则不调用，

if(null == savedInstanceState) {
        new InitializeEnvironment().execute();
    }

但请确保您之前的 Activity 没有覆盖 onActivityResult()

于 2013-03-22T08:40:49.483 回答