带进度的progressBar

优化版本 v2： 进入

1.实现思路：

计算progressBar的宽度，计算屏幕的宽度。根据currentProgress（）计算出，progress点在屏幕上的偏移量。然后不断更新偏移量！

这里使用线性布局，嵌套两个TextView
（如果不需要实时更新，定义一个TextView 通过偏移量动态更新TextView的setPadding（leftPadding,0,0,0），如果需要动态更新，就需要定义两个组件。给前一个设置leftPadding，第二个设置具体跟随浮动的内容）。

2.上效果图

3.使用场景:
对于精度要求不高的需求可以使用。因为上面的偏移量和下面的进度有些许的偏差。

4.对比:
市面上同类解决方案，该方式代码量少。容易上手。扩展容易。缺点就是上下位置有偏差。

贴代码：

布局

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/text_white"
    android:orientation="vertical">


    <LinearLayout
        android:id="@+id/line_container"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:gravity="center"
        android:orientation="vertical">

        <LinearLayout
            android:layout_width="fill_parent"
            android:layout_height="wrap_content">

            <TextView
                android:id="@+id/txt_cursor"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content" />

            <TextView
                android:id="@+id/progress_txt"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:background="@drawable/icon_gas_bg"
                android:gravity="center"
                android:lines="1"
                android:textColor="@color/text_white"
                android:textSize="8sp"
                android:visibility="gone" />
        LinearLayout>

        <SeekBar
            android:id="@+id/seekBar_progressBar"
            android:layout_width="match_parent"
            android:layout_height="2dp"
            android:layout_gravity="center_vertical"
            android:layout_marginLeft="@dimen/width_35"
            android:layout_marginRight="@dimen/width_35"
            android:layout_marginTop="10dp"
            android:maxHeight="2dp"
            android:padding="-2dp"
            android:progressDrawable="@drawable/progress_background"
            android:thumb="@null"
            android:thumbOffset="0dp" />

        <TextView
            android:id="@+id/txt_bytevalue"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="15dp" />

        <ImageView
            android:id="@+id/img_close_pdfdown"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="143dp" />

        <Button
            android:id="@+id/button"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_horizontal"
            android:text="New Button" />

    LinearLayout>


LinearLayout>

---

代码块：

package com.example.payui;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.DisplayMetrics;
import android.view.View;
import android.widget.SeekBar;
import android.widget.TextView;

import java.util.Timer;
import java.util.TimerTask;

public class MainActivity extends Activity {

    private SeekBar customSeekBar;
    private TextView txtCur;
    private int screenWidth;
    private int defaultOff;
    private TextView progress_txt;
    private TextView txt_bytevalue;
    private int temp = 0;

    int count = 0;
    Handler handler = new Handler(new Handler.Callback() {
        @Override
        public boolean handleMessage(Message msg) {
            showProgressLoading(msg.what);
            showDownLoadingText(msg.what, 555524);
            return false;
        }
    });

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.pdfactivity);
        DisplayMetrics displayMetrics = getDisplayMetrics(this);
        screenWidth = displayMetrics.widthPixels;
        defaultOff = (int) getResources().getDimension(R.dimen.width_35) * 2;
        txtCur = (TextView) findViewById(R.id.txt_cursor);
        txt_bytevalue = (TextView) findViewById(R.id.txt_bytevalue);
        progress_txt = (TextView) findViewById(R.id.progress_txt);
        customSeekBar = (SeekBar) findViewById(R.id.seekBar_progressBar);
        findViewById(R.id.button).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                customSeekBar.setProgress(0);
                count = 0;
                initValue();
            }
        });
        initValue();
    }

    public void initValue() {
        Timer timer = new Timer();
        timer.schedule(new TimerTask() {
            @Override
            public void run() {
                final int go = count++;
                if (go <= 100) {
                    Message message = Message.obtain();
                    message.what = go;
                    handler.sendMessage(message);
                }
            }
        }, 0, 300);
    }

    private void showProgressLoading(long progress) {
        final int progressWidth = screenWidth - defaultOff;
        int offLeftWidth = (int) getResources().getDimension(R.dimen.width_35);
        int endPosition = screenWidth - (int) getResources().getDimension(R.dimen.width_35);
        int startPositon = (int) (progress * (progressWidth / 100)) + offLeftWidth;
        int offPosition = startPositon > endPosition ? endPosition : startPositon;
        if (progress == 0) {
            txtCur.setPadding(offLeftWidth, 0, 0, 0);
        } else if (progress == 100) {
            txtCur.setPadding(progressWidth + (int) getResources().getDimension(R.dimen.width_23), 0, 0, 0);
        } else {
            txtCur.setPadding(offPosition, 0, 0, 0);
        }
        progress_txt.setText(progress + "%");
        customSeekBar.setProgress((int) progress);

    }

    private void showDownLoadingText(long progress, long fileSize) {
        if (progress >= 1) {
            progress_txt.setVisibility(View.VISIBLE);
        }
        temp = (int) (fileSize / 100);
        txt_bytevalue.setText("DownLoading..." + (progress < 100 ? progress * temp : fileSize) + "k/" + fileSize + "k");
    }

    public static DisplayMetrics getDisplayMetrics(Context context) {
        DisplayMetrics dm = null;
        if (context != null) {
            dm = new DisplayMetrics();
            dm = context.getApplicationContext().getResources().getDisplayMetrics();
            return dm;
        }
        return new DisplayMetrics();
    }

}

这段代码只作为学习使用参考；