6.ProgressBar进度条

一、ProgressBar常用属性详解

1.android:max：进度条的最大值<br />    2.android:progress：进度条已完成进度值（在java中设置）<br />    3.android:indeterminate：如果设置成true，则进度条不精确显示进度<br />    4.style="?android:attr/progressBarStyleHorizontal"水平进度条

二、显示隐藏进度条设置

1.布局activity_main.xml代码

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    >
    <ProgressBar
        android:id="@+id/pb_one"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        />
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="btn_one"
        android:text="显示隐藏进度条"
        />
</LinearLayout>

2.MainActivity文件代码

package com.example.test;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ProgressBar;
public class MainActivity extends AppCompatActivity {
    private ProgressBar pb_one;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
         pb_one = findViewById(R.id.pb_one);
    }
    public void btn_one(View view) {
        if (pb_one.getVisibility()==View.GONE){
            pb_one.setVisibility(View.VISIBLE);
        }else{
            pb_one.setVisibility(View.GONE);
        }
    }
}

3.效果图：<br />![image.png](https://cdn.nlark.com/yuque/0/2021/png/1574587/1621925681634-5988d1ac-659b-417a-8ca3-7ed868c1d1d7.png#clientId=u2192a832-ffde-4&from=paste&height=91&id=u5d422e4d&margin=%5Bobject%20Object%5D&name=image.png&originHeight=91&originWidth=154&originalType=binary&size=5387&status=done&style=none&taskId=ud312cd07-30e3-48d1-9b9e-40ab7c6a233&width=154)![image.png](https://cdn.nlark.com/yuque/0/2021/png/1574587/1621925692995-877a8039-9ad2-4df8-87af-5103d1ec541f.png#clientId=u2192a832-ffde-4&from=paste&height=105&id=uf805b7ae&margin=%5Bobject%20Object%5D&name=image.png&originHeight=105&originWidth=156&originalType=binary&size=5378&status=done&style=none&taskId=ue9007279-0fb6-4d74-a093-39420f6ed17&width=156)

三、模拟下载的实现

1.布局activity_main.xml代码

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
    >
    <ProgressBar
        android:id="@+id/pb_two"
        android:layout_width="350dp"
        android:layout_height="wrap_content"
        android:max="100"
        style="?android:attr/progressBarStyleHorizontal"
        />
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="btn_two"
        android:text="已完成的进度值"
        />
</LinearLayout>

2.MainActivity文件代码

package com.example.test;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ProgressBar;
public class MainActivity extends AppCompatActivity {
    private ProgressBar pb_two;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        pb_two = findViewById(R.id.pb_two);
    }
    public void btn_two(View view) {
        int progress=pb_two.getProgress();
        progress=progress+5;
        pb_two.setProgress(progress);
    }
}

3.效果图（最大值为100，每点击一下增加5/100的值，加满即为下载成功）：<br />![image.png](https://cdn.nlark.com/yuque/0/2021/png/1574587/1621926326151-3b65d700-167f-4148-b14d-6a19b3e96261.png#clientId=u2192a832-ffde-4&from=paste&height=116&id=u801768b1&margin=%5Bobject%20Object%5D&name=image.png&originHeight=116&originWidth=294&originalType=binary&size=7913&status=done&style=none&taskId=u287e9e05-f290-4db5-8730-c2f831e584d&width=294)

四、不显示进度完成值

1.加该属性，就不显示<br />![image.png](https://cdn.nlark.com/yuque/0/2021/png/1574587/1621926468308-6a0cd9df-7765-4717-9945-164917fa0d18.png#clientId=u2192a832-ffde-4&from=paste&height=20&id=ue462e864&margin=%5Bobject%20Object%5D&name=image.png&originHeight=20&originWidth=224&originalType=binary&size=1395&status=done&style=none&taskId=u8a75d0cd-8f78-403d-abba-2338b899cc3&width=224)<br />    2.代码如下：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
    >
    <ProgressBar
        android:layout_width="350dp"
        android:layout_height="wrap_content"
        android:max="100"
        android:indeterminate="true"
        style="?android:attr/progressBarStyleHorizontal"
        />
</LinearLayout>

3.效果图：<br />![image.png](https://cdn.nlark.com/yuque/0/2021/png/1574587/1621926605777-1c6fb84c-17c0-421f-85f4-8c378fb6f24e.png#clientId=u2192a832-ffde-4&from=paste&height=236&id=u0c09ee45&margin=%5Bobject%20Object%5D&name=image.png&originHeight=236&originWidth=762&originalType=binary&size=33513&status=done&style=none&taskId=uc9ade444-25d4-48a7-b46f-1979a974e81&width=762)