阅读《Android 从入门到精通》（17）——进度条

Posted 2020-10-02 yutingliuyl

进度条（ProgressBar）

java.lang.Object;
android.view.View;
android.widget.ProgressBar;

ProgressBar 类方法

ProgressBar 演示样例

完整project：http://download.csdn.net/detail/sweetloveft/9416791

以下我们要学习该类中最经常使用的方法。主要是 setMax 和 setProgress 等方法。

1.MainActivity.java

package com.sweetlover.activity;

import com.sweetlover.progressbar.R;

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 MainActivity extends Activity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		// TODO Auto-generated method stub
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		
		final ProgressBar progressHorizontal = (ProgressBar) findViewById(R.id.progress_horizontal);
        setProgress(progressHorizontal.getProgress() * 100);
        setSecondaryProgress(progressHorizontal.getSecondaryProgress() * 100);
        
        Button button = (Button) findViewById(R.id.increase);
        button.setOnClickListener(new OnClickListener() {
            public void onClick(View v) {
                progressHorizontal.incrementProgressBy(1);
                // Title progress is in range 0..10000
                setProgress(100 * progressHorizontal.getProgress());
            }
        });

        button = (Button) findViewById(R.id.decrease);
        button.setOnClickListener(new OnClickListener() {
            public void onClick(View v) {
                progressHorizontal.incrementProgressBy(-1);
                // Title progress is in range 0..10000
                setProgress(100 * progressHorizontal.getProgress());
            }
        });

        button = (Button) findViewById(R.id.increase_secondary);
        button.setOnClickListener(new OnClickListener() {
            public void onClick(View v) {
                progressHorizontal.incrementSecondaryProgressBy(1);
                // Title progress is in range 0..10000
                setSecondaryProgress(100 * progressHorizontal.getSecondaryProgress());
            }
        });

        button = (Button) findViewById(R.id.decrease_secondary);
        button.setOnClickListener(new OnClickListener() {
            public void onClick(View v) {
                progressHorizontal.incrementSecondaryProgressBy(-1);
                // Title progress is in range 0..10000
                setSecondaryProgress(100 * progressHorizontal.getSecondaryProgress());
            }
        });
	}
}

2.activity_main.xml

<?
xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:padding="30dp" >

    <ProgressBar android:id="@+id/progress_horizontal"
        style="?
android:attr/progressBarStyleHorizontal"
        android:layout_width="200dip"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:max="100"
        android:progress="50"
        android:secondaryProgress="75" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_marginTop="20dp"
        android:text="@string/normal" />


    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:layout_marginTop="20dp" >

        <Button
            android:id="@+id/decrease"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/decrease" />

        <Button
            android:id="@+id/increase"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/increase" />

    </LinearLayout>

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_marginTop="20dp"
        android:text="@string/custom" />


    <LinearLayout
        android:orientation="horizontal"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:layout_marginTop="20dp" >

        <Button
            android:id="@+id/decrease_secondary"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/decrease" />

        <Button
            android:id="@+id/increase_secondary"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="@string/increase" />

    </LinearLayout>

</LinearLayout>

3.strings.xml

<resources>

    <string name="app_name">ProgressBar</string>
    <string name="normal">默认进度条</string>
    <string name="decrease">降低</string>
    <string name="increase">添加</string>
    <string name="custom">自己定义进度条</string>
    

</resources>

4.AndroidManifest.xml

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.sweetlover.progressbar"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="19" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity android:name="com.sweetlover.activity.MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>
                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>
    </application>

</manifest>