Question

我在android中遇到了不确定的进展问题。我有一个按钮，单击按钮时会出现不确定的进度条，在任务结束时，进度条应该消失。

但我无法做到这一点。

package com.indeterminate;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.Window;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.*;

 public class IndeterminateProgressBarActivity extends Activity {


@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub

    super.onCreate(savedInstanceState);
    final ProgressBar pb=new ProgressBar(this);
    pb.setVisibility(View.GONE);
    Button b =new Button(this);
    b.setText("Click to start spinning");
    b.setOnClickListener(new OnClickListener(){

        @Override
        public void onClick(View v) {
            pb.setVisibility(View.VISIBLE);
            // Want to write some code
            pb.setVisibility(View.GONE);

            // But the progress bar is not shown on the screen

    LinearLayout l=new LinearLayout(this);
    l.addView(pb);
    l.addView(b);

    this.setContentView(l);
}

}

Answer 1

使用异步任务。在onClick电话

new SomeTask(0).execute();

/** Inner class for implementing progress bar before fetching data **/
    private class SomeTask extends AsyncTask<Void, Void, Integer> 
    {
        private ProgressDialog Dialog = new ProgressDialog(yourActivityClass.this);
        @Override
        protected void onPreExecute()
        {

            Dialog.setMessage("Doing something...");
            Dialog.show();
        }

        @Override
        protected Integer doInBackground(Void... params) 
        {
            //Task for doing something 

            return 0;
        }

        @Override
        protected void onPostExecute(Integer result)
            {

            if(result==0)
            {
//do some thing
            }

    // after completed finished the progressbar
            Dialog.dismiss();
        }

    }

Answer 2

对于这个概念，你应该asynctask类

on preExecute你可以设置progressBar可见，在DoInBackGround你可以写你的代码，在PostExecute你可以设置progressBar Gone的可见性。

static class PleaseWait extends AsyncTask<void, void, Void> {

final ProgressBar pb = new ProgressBar（this）; pb.setVisibility（View.GONE）;

    protected void onPreExecute() {
                 pb.setVisibility(View.VISIBLE);

    }

    protected Void doInBackground(Object... args) {
        //Write some code here
    }

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

    }
}

你可以调用新的PleaseWait（）。执行;

android不确定进度条问题

2 个答案: