一、各自的功能及用途

ProgressBar：进度条，主要向用户展示当前任务的完成进度，例如游戏加载、app更新、文件下载等；

SeekBar：进度条的升级款，与ProgressBar不同的是用户可以自行拖动以控制进度；音量大小、音视频的播放进度等都可以用它实现；

RatingBar：星级评分条，这里我只用三个字描述：“打分的”，多用于电商类app以及各大应用商店，比如对某款app、某件商品评分

二、简单使用

1、打开之前的布局文件activity_main.xml，先删掉之前定义的所有控件，然后再添加今天我们讲到的控件,如图1

图1

2、打开MainActivity.java,因为布局中之前定义的控件已经被删掉，所以代码中也需要清理，不然因为找不到控件id会报错；清掉后定义并绑定今天的控件

public class MainActivity extends AppCompatActivity { private ProgressBar pbProgress; private SeekBar sbProgress; private RatingBar rbEvaluate; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); initView(); pbProgress.setProgress(30); sbProgress.setMax(100); setListener(); } private void setListener() { sbProgress.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() { @Override public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) { Log.e("onProgressChanged======",progress+""); } @Override public void onStartTrackingTouch(SeekBar seekBar) { } @Override public void onStopTrackingTouch(SeekBar seekBar) { } }); rbEvaluate.setOnRatingBarChangeListener(new RatingBar.OnRatingBarChangeListener() { @Override public void onRatingChanged(RatingBar ratingBar, float rating, boolean fromUser) { Log.e("onRatingChanged======",rating+""); } }); } private void initView() { rbEvaluate=findViewById(R.id.rb_evaluate); pbProgress=findViewById(R.id.pb_progress); sbProgress=findViewById(R.id.sb_progress); }}

代码中我用setProgress()方法为pbProgress设置了当前进度

三、官网对于上述控件的属性介绍

1、RatingBar

android:isIndicator

Whether this rating bar is an indicator (and non-changeable by the user).

android:numStars

The number of stars (or rating items) to show.

android:rating

The rating to set by default.

android:stepSize

The step size of the rating.

2、SeekBar

android:thumb

Draws the thumb on a seekbar.

3、ProgressBar

android:animationResolution

Timeout between frames of animation in milliseconds.

android:indeterminate

Allows to enable the indeterminate mode.

android:indeterminateBehavior

Defines how the indeterminate mode should behave when the progress reaches max.

android:indeterminateDrawable

Drawable used for the indeterminate mode.

android:indeterminateDuration

Duration of the indeterminate animation.

android:indeterminateOnly

Restricts to ONLY indeterminate mode (state-keeping progress mode will not work).

android:indeterminateTint

Tint to apply to the indeterminate progress indicator.

android:indeterminateTintMode

Blending mode used to apply the indeterminate progress indicator tint.

android:interpolator

Sets the acceleration curve for the indeterminate animation.

android:max

Defines the maximum value.

android:maxHeight

An optional argument to supply a maximum height for this view.

android:maxWidth

An optional argument to supply a maximum width for this view.

android:min

Defines the minimum value.

android:minHeight

android:minWidth

android:mirrorForRtl

Defines if the associated drawables need to be mirrored when in RTL mode.

android:progress

Defines the default progress value, between 0 and max.

android:progressBackgroundTint

Tint to apply to the progress indicator background.

android:progressBackgroundTintMode

Blending mode used to apply the progress indicator background tint.

android:progressDrawable

Drawable used for the progress mode.

android:progressTint

Tint to apply to the progress indicator.

android:progressTintMode

Blending mode used to apply the progress indicator tint.

android:secondaryProgress

Defines the secondary progress value, between 0 and max.

android:secondaryProgressTint

Tint to apply to the secondary progress indicator.

android:secondaryProgressTintMode

Blending mode used to apply the secondary progress indicator tint.

四、补充

可以看到在代码中我用到了Log.e()，它是用于向控制台输出日志的，除了使用调试**以外，合理使用日志输出也可以帮我们快速定位问题，除了e外，级别由低到高还有v, d, i, w；e的级别是**的

图2

五、运行截图

最后附上一张运行效果图