Android学习笔记之ProgressBar案例分析 _android学习

但使书种多，会有岁稔时。这篇文章主要讲述Android学习笔记之ProgressBar案例分析相关的知识，希望能为你提供帮助。

（1）

< RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" android:paddingBottom="@dimen/activity_vertical_margin" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" tools:context=".MainActivity" > < TextView android:id="@+id/textView1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:text="进度条的使用：" /> < ProgressBar android:id="@+id/progressBar1" style="?android:attr/progressBarStyleHorizontal" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignLeft="@+id/button1" android:layout_alignRight="@+id/button1" android:layout_below="@+id/textView1" android:layout_marginTop="30dp" /> < Button android:id="@+id/button1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignLeft="@+id/textView1" android:layout_below="@+id/progressBar1" android:layout_marginLeft="74dp" android:layout_marginTop="146dp" android:text="下载图片" /> < /RelativeLayout>

（2）

package com.example.progressbar; import android.app.Activity; 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; import android.widget.ProgressBar; public class MainActivity extends Activity { private Button button1; private ProgressBar progressBar1; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); button1 = (Button) this.findViewById(R.id.button1); progressBar1 = (ProgressBar) this.findViewById(R.id.progressBar1); progressBar1.setMax(100); // 设置最大值为100button1.setOnClickListener(new OnClickListener() {@Override public void onClick(View v) { new MyTask().execute(); } }); } class MyTask extends AsyncTask< Void, Integer, Void> { @Override protected void onProgressUpdate(Integer... values) { super.onProgressUpdate(values); progressBar1.setProgress(values[0]); }@Override protected Void doInBackground(Void... params) {int i = 1; while (i < = 100) { try { Thread.sleep(500); } catch (Exception e) { // TODO: handle exception } publishProgress(i); i++; } return null; } } @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.main, menu); return true; }}

（3）演示效果
【Android学习笔记之ProgressBar案例分析】