自定义属性

<?xml version="1.0" encoding="utf-8"?>
<resources>

    <declare-styleable name="HorizentailProgressBar">
        <attr name="progress_text_color" format="color" />
        <attr name="progress_text_size" format="dimension" />
        <attr name="progress_text_offset" format="dimension" />
        <attr name="progress_unreach_color" format="color" />
        <attr name="progress_unreach_height" format="dimension" />
        <attr name="progress_reach_color" format="color" />
        <attr name="progress_reach_height" format="dimension" />
    </declare-styleable>

</resources>

创建横向进度条类

public class HorizentailProgressBar extends ProgressBar {

    // 字体颜色
    private int textColor = 0x66FF0000;
    // 字体大小
    private int textSize = sp2px(16);
    // 字体两旁的间隔
    private int textOffset = dp2px(10);
    // 完成路径的颜色
    private int reachColor = 0x66FF0000;
    // 完成路径的高度
    private int reachHeight = dp2px(2);
    // 未完成路径的颜色
    private int unreachColor = 0x22FF0000;
    // 未完成路径的颜色
    private int unreachHeight = dp2px(2);
    // 控件的真实宽度
    private int realWidth = 0;
    // 是否需要绘制未完成路径
    private boolean unreachFlag = true;

    private Paint paint = new Paint();

    public HorizentailProgressBar(Context context) {
        this(context, null);
    }

    public HorizentailProgressBar(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public HorizentailProgressBar(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        obtainStyleAttrs(context, attrs);
    }

    private void obtainStyleAttrs(Context context, AttributeSet attrs) {
        TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.HorizentailProgressBar);
        textSize = ta.getDimensionPixelSize(R.styleable.HorizentailProgressBar_progress_text_size, textSize);
        textColor = ta.getColor(R.styleable.HorizentailProgressBar_progress_text_color, textColor);
        textOffset = (int) ta.getDimension(R.styleable.HorizentailProgressBar_progress_text_offset, textOffset);
        reachColor = ta.getColor(R.styleable.HorizentailProgressBar_progress_reach_color, reachColor);
        reachHeight = (int) ta.getDimension(R.styleable.HorizentailProgressBar_progress_reach_height, reachHeight);
        unreachColor = ta.getColor(R.styleable.HorizentailProgressBar_progress_unreach_color, unreachColor);
        unreachHeight = (int) ta.getDimension(R.styleable.HorizentailProgressBar_progress_unreach_height, unreachHeight);
        ta.recycle();
    }

    @Override
    protected synchronized void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        int width = MeasureSpec.getSize(widthMeasureSpec);
        int height = measureHeight(heightMeasureSpec);
        setMeasuredDimension(width, height);

        // 获取控件真实的宽度
        realWidth = getMeasuredWidth() - getPaddingLeft() - getPaddingRight();
    }

    // 获取控件的高度
    private int measureHeight(int heightMeasureSpec) {
        int result = 0;
        int heightSize = MeasureSpec.getSize(heightMeasureSpec);
        int heightMode = MeasureSpec.getMode(heightMeasureSpec);
        if (heightMode == MeasureSpec.EXACTLY) {    // 具体高度，如30dp...
            result = heightSize;
        } else {                    // 看是字体高，还是ProgressBar的线高
            int lineHeight = dp2px(Math.max(unreachHeight, reachHeight));
            int textHeight = sp2px((int) Math.abs((paint.descent() - paint.ascent())));
            if (lineHeight > textHeight) {
                result = getPaddingTop() + getPaddingBottom() + lineHeight;
            } else {
                result = getPaddingTop() + getPaddingBottom() + textHeight;
            }
        }
        return result;
    }

    @Override
    protected synchronized void onDraw(Canvas canvas) {
        canvas.save();
        // 开始绘制的偏移
        canvas.translate(getPaddingLeft(), getHeight() / 2);

        // 进度值
        String text = getProgress() + "%";
        int textWidth = (int) paint.measureText(text);

        // 绘制完成路径
        float end = (getProgress() * 1.0f / getMax()) * realWidth;
        if (end + textOffset + textWidth >= realWidth) {
            end = realWidth - textOffset - textWidth;
            unreachFlag = false;
        }
        paint.setColor(reachColor);
        paint.setStrokeWidth(reachHeight);
        canvas.drawLine(0, 0, end, 0, paint);

        // 绘制进度值
        float x = end + textOffset / 2;
        paint.setColor(textColor);
        paint.setTextSize(textSize);
        int y = (int) (-(paint.descent() + paint.ascent()) / 2);
        canvas.drawText(text, x, y, paint);

        // 绘制未完成的路径
        if (unreachFlag) {
            float start = end + textWidth + textOffset;
            paint.setColor(unreachColor);
            paint.setStrokeWidth(unreachHeight);
            canvas.drawLine(start, 0, realWidth, 0, paint);
        }
        canvas.restore();
    }

    private int dp2px(int value) {
        return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, value,
                getResources().getDisplayMetrics());
    }

    private int sp2px(int value) {
        return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_SP, value,
                getResources().getDisplayMetrics());
    }

}

在布局文件中引用

<?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"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <com.zc.myapp.views.demo.HorizentailProgressBar
        android:id="@+id/progress"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="30dp"
        android:layout_marginLeft="15dp"
        android:layout_marginRight="15dp"
        app:progress_reach_color="#77FF0000"
        app:progress_reach_height="2dp"
        app:progress_text_color="#77FF0000"
        app:progress_text_size="16sp"
        app:progress_text_offset="10dp"
        app:progress_unreach_color="#33FF0000"
        app:progress_unreach_height="2dp"
        android:progress="0" />

</LinearLayout>

在Activity中使用

public class MainActivity extends AppCompatActivity {

    private HorizentailProgressBar progressBar;

    private Handler handler = new Handler() {
        @Override
        public void handleMessage(@NonNull Message msg) {
            int progress = progressBar.getProgress();
            progressBar.setProgress(++progress);
            if (progress >= 100) {
                handler.removeMessages(111);
            }
            handler.sendEmptyMessageDelayed(111, 100);
        }
    };

    @SuppressLint("WrongViewCast")
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        progressBar = findViewById(R.id.progress);
        handler.sendEmptyMessage(111);
    }

}