ProgressBar的使用

简单的使用下ProgressBar...

1.设置进度条的可见性通过setVisibility(int v)方法.注意v的取值.如下描述:

View 的setVisibility有三个值可以设置： 
VISIBLE--->可见 
INVISIBLE--->不可见，但这个View在ViewGroupt中仍保留它的位置，不重新layout 
GONE---->不可见，但这个View在ViewGroupt中不保留位置，重新layout,那后面的view就会取代他的位置。 

2.设置进度条长度通过setProgress()方法.

创建项目步骤:

step1:新建android工程，命名为ProgressBarTest。

step2:设置布局文件main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/hello" />
<!--
    设置水平的进度条 style="?android:attr/progressBarStyleHorizontal" 
    设置转圈的进度条style="?android:attr/progressBarStyle"
-->    
    <ProgressBar 
        android:id="@+id/firstprogress"
        style="?android:attr/progressBarStyleHorizontal"
        android:layout_width="200dp"
        android:layout_height="wrap_content"
        android:visibility="gone"/>
    
    <ProgressBar 
        android:id="@+id/secondprogress"
        style="?android:attr/progressBarStyle"
        android:layout_width="200dp"
        android:layout_height="wrap_content"
        android:visibility="gone"/>
    
    <Button 
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="确定"/>

</LinearLayout>

step3:设计主类ProgressBarTest.java

package com.cb.progressbar;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ProgressBar;

public class ProgressBarTest extends Activity {
    private ProgressBar mProgressBar1;
    private ProgressBar mProgressBar2;
    private Button mButton;
    
    private int i = 0;
    
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        mProgressBar1 = (ProgressBar)findViewById(R.id.firstprogress);
        mProgressBar2 = (ProgressBar)findViewById(R.id.secondprogress);
        mButton = (Button)findViewById(R.id.button);
        
        mButton.setOnClickListener(new OnClickListener() {
            
            @Override
            public void onClick(View v) {
                if (i==0) {
                    //设置进度条可见
                    mProgressBar1.setVisibility(View.VISIBLE);
                    mProgressBar2.setVisibility(View.VISIBLE);
                }
                else if (i < mProgressBar1.getMax()) {
                    //设置点击进度条时，进度条进度增加
                    mProgressBar1.setProgress(i);
                    //设置第二进度条(浅色的那条)
                    mProgressBar1.setSecondaryProgress(i+10);
                    mProgressBar2.setProgress(i);
                }
                else {
                    //当进度条走完时，设置进度条不可见
                    mProgressBar1.setVisibility(View.GONE);
                    mProgressBar2.setVisibility(View.GONE);
                }
                i = i+10;
            }
        });
        
    }
}

step4:执行结果如下