android - 帮助 ProgressDisplay

Question

我希望我的应用在连接到在线资源时以 ProgressDialog 开始，抓取数据，解析数据，然后用它填充微调器。下面代码中的 DirectoryTransaction.doDepts() 将数据连接并解析为 String[][] DeptResults。我已经尝试了其他问题和答案但没有成功，并且真的很想让它起作用。就像现在一样，应用程序在完成所有这些工作时似乎会卡住几秒钟。我宁愿让它显示对话框。

这是我现在的代码:

package com.test.directory;

import android.app.Activity;
import android.content.Intent;
import android.os.Build;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.Toast;

public class Directory extends Activity {

    public static boolean test = false;
    public static int Start = 1;
    public static int Page = 1;
    public static int ResultsCount = 0;
    public static int sdk = new Integer(Build.VERSION.SDK).intValue();
    public static String[] Fields = new String[6];
    public static String[][] DeptResults;
    public static String[][] ReturnResults;
    public static String[] ResultsDetails = new String[11];

    public EditText fname = (EditText) findViewById(R.id.fname);
    public EditText lname = (EditText) findViewById(R.id.lname);
    public EditText aim = (EditText) findViewById(R.id.aim);
    public EditText phone = (EditText) findViewById(R.id.phone);
    public Spinner depts = (Spinner) findViewById(R.id.dept);


    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.searchscreen);

        DirectoryTransaction.doDepts();

        //Sets up and fills the department spinner
        final ArrayAdapter<CharSequence> deptsAdapter = new ArrayAdapter<CharSequence>(this, android.R.layout.simple_spinner_item);
        deptsAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        depts.setAdapter(deptsAdapter);
        for(int i = 0 ; i < DeptResults.length ; i++){
            deptsAdapter.add(DeptResults[i][0]);            
        }

        //Search button
        findViewById(R.id.search).setOnClickListener(new OnClickListener() {
            public void onClick(View v) {

                Start = 1;
                Page = 1;

              //Put all the info from the fields into a string array
                Fields[0] = fname.getText().toString();
                Fields[1] = lname.getText().toString();
                Fields[2] = aim.getText().toString();
                Fields[3] = phone.getText().toString();
                Fields[4] = DeptResults[(int)depts.getSelectedItemId()][1];
                Fields[5] = Integer.toString(Start);

                DirectoryTransaction.doSearch(Directory.Start, Fields[0], Fields[1], Fields[2], Fields[4], Fields[3]);


              //Shows error if more than 300 results
                if(ResultsCount > 300){
                    Toast.makeText(Directory.this, "Too many results found, please narrow your search.", Toast.LENGTH_LONG).show();
                }else{              
              //Load a new Intent and start the results activity
                Intent i = new Intent(v.getContext(), DirectoryResults.class);
                startActivity(i);
                }
            }
        });

        //Clear Button
        findViewById(R.id.clear).setOnClickListener(new OnClickListener() {
            public void onClick(View v) {
                //Clears all the fields, sets the Spinner to 0.
                fname.setText("");
                lname.setText("");
                aim.setText("");
                phone.setText("");
                depts.setSelection(0);
            }
        });
    }
}

基本上，这是我在 ProgressDialog 显示时想要做的事情。

        DirectoryTransaction.doDepts();

        //Sets up and fills the department spinner
        final ArrayAdapter<CharSequence> deptsAdapter = new ArrayAdapter<CharSequence>(this, android.R.layout.simple_spinner_item);
        deptsAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        depts.setAdapter(deptsAdapter);
        for(int i = 0 ; i < DeptResults.length ; i++){
            deptsAdapter.add(DeptResults[i][0]);            
        }

有什么想法/例子可以告诉我我需要什么吗？我已经看了很多，但一直没弄明白。

谢谢，我成功了。我不确定我是否需要它，所以我会玩弄它。这是代码:

package com.test.directory;

import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.os.AsyncTask;
import android.os.Build;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.Spinner;
import android.widget.Toast;

public class Directory extends Activity {

    public static boolean test = false;
    public static int Start = 1;
    public static int Page = 1;
    public static int ResultsCount = 0;
    public static int sdk = new Integer(Build.VERSION.SDK).intValue();
    public static String[] Fields = new String[6];
    public static String[][] DeptResults;
    public static String[][] ReturnResults;
    public static String[] ResultsDetails = new String[11];

    public ArrayAdapter<CharSequence> deptsAdapter;

    ProgressDialog dialog;
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.searchscreen);

        new getAllData().execute(this);

        final EditText fname = (EditText) findViewById(R.id.fname);
        final EditText lname = (EditText) findViewById(R.id.lname);
        final EditText aim = (EditText) findViewById(R.id.aim);
        final EditText phone = (EditText) findViewById(R.id.phone);
        final Spinner depts = (Spinner) findViewById(R.id.dept);

        //Sets up and fills the department spinner
        deptsAdapter = new ArrayAdapter<CharSequence>(Directory.this, android.R.layout.simple_spinner_item);
        deptsAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        depts.setAdapter(deptsAdapter);

      //Search button
        findViewById(R.id.search).setOnClickListener(new OnClickListener() {
            public void onClick(View v) {

                Start = 1;
                Page = 1;

              //Put all the info from the fields into a string array
                Fields[0] = fname.getText().toString();
                Fields[1] = lname.getText().toString();
                Fields[2] = aim.getText().toString();
                Fields[3] = phone.getText().toString();
                Fields[4] = DeptResults[(int)depts.getSelectedItemId()][1];
                Fields[5] = Integer.toString(Start);

                DirectoryTransaction.doSearch(Directory.Start, Fields[0], Fields[1], Fields[2], Fields[4], Fields[3]);


              //Shows error if more than 300 results
                if(ResultsCount > 300){
                    Toast.makeText(Directory.this, "Too many results found, please narrow your search.", Toast.LENGTH_LONG).show();
                }else{
              //Load a new Intent and start the results activity
                Intent i = new Intent(v.getContext(), DirectoryResults.class);
                startActivity(i);
                }
            }
        });

      //Clear Button
        findViewById(R.id.clear).setOnClickListener(new OnClickListener() {
            public void onClick(View v) {
              //Clears all the fields, sets the Spinner to 0.
                fname.setText("");
                lname.setText("");
                aim.setText("");
                phone.setText("");
                depts.setSelection(0);
            }
        });
    }

    private class getAllData extends AsyncTask<Context, Void, Cursor> {
        protected void onPreExecute () {
            dialog = ProgressDialog.show(Directory.this, "", 
                    "Loading. Please wait...", true);
        }

        @Override
        protected Cursor doInBackground(Context... params) {
            DirectoryTransaction.doDepts();

            return null;
        }

        protected void onPostExecute(Cursor c) {

            for(int i = 0 ; i < DeptResults.length ; i++){
                deptsAdapter.add(DeptResults[i][0]);            
            }
            //update the UI or do soemthing
            dialog.dismiss();
        }
    }

}

Answer 1

这是我的做法:

我将 ProgressDialog dialog; 放在我的类文件的顶部。

在我的 onCreate() 方法中我有这个:

new getAllData().execute(this);   

由于我的任务需要一些时间，所以我让它在后台线程中运行(如果您的应用“卡住”，我建议您也这样做)。后台线程的代码如下所示:

 private class getAllData extends AsyncTask<Context, Void, Cursor> {
    protected void onPreExecute () {
        dialog = ProgressDialog.show(Shows.this, "", 
                "Loading shows. Please wait...", true);
    }

    @Override
    protected Cursor doInBackground(Context... params) {
        //do all the work
    }

    protected void onPostExecute(Cursor c) {
        //update the UI or do soemthing
        dialog.dismiss();
    }
}

这里有更多关于 ASync 的信息:http://developer.android.com/reference/android/os/AsyncTask.html

如果您要使用 Async，您的 onPreExecute 将显示对话框，doInBackground() 将获取您需要从网络获取的任何内容，然后 onPostExecute() 会将所有内容粘贴到您的微调器中。

如果您不想这样做，那么您仍然可以在完成时执行 ProgressDialog.show(...) 和 dialog.dimiss()