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2024年04月09日

HarmonyOS实现Material风格的下拉刷新

介绍

Ohos-MaterialRefreshLayout是一个自定义Material风格下拉刷新控件，支持设置水波纹效果，支持下拉刷新侵入式和非侵入式，初始化自动刷新及上滑加载更多，支持刷新头部自定义图案，上拉加载更多等。该控件一般配合ListContainer使用,因涉及事件分发操作，本库中使用了三方控件NestedListContainer、事件分发等方便处理事件拦截分发事件。

效果图:

自定义控件结构

MaterialRefreshLayout控件，首先初始化设置头部、脚部布局,在手势下滑时显示头部布局，动态设置头部高度，展示下拉刷新效果，在页面底部向上滑动时显示脚部布局，展示上拉加载更多效果，松手时图形即开始旋转动画。

下拉圆形转动风格MaterialRefreshLayout

1.MaterialRefreshLayout包含自定义头部布局MaterialHeaderView和脚部布局MaterialFooterView。

2.头部MaterialHeaderView包含圆形转动条CircleProgressBar和下拉波纹MaterialWaveView。

3.脚部布局MaterialFooterView同头部结构一致，包含圆形转动条CircleProgressBar和下拉波纹MaterialWaveView。

4.CircleProgressBar包含有自定义图形的MaterialProgressDrawable，设置圆形的转动图案。

下拉自定义笑脸风格MaterialRefreshLayout

1.MaterialRefreshLayout包含SunLayout头部布局和脚部布局MaterialFooterView。

2.SunLayout头部包含滚动短线SunLineView和笑脸SunFaceView。

2.当有手势下滑时，自定义短线SunLineView，开始旋转动画，监听刷新动作，在onSizeChanged中动态改变图形大小。

3.当手势向下滑动时，自定义笑脸图形SunFaceView，监听刷新动作，在onSizeChanged中动态改变图形大小。

代码实现解读

首先在拦截事件中根据手指的滑动距离，设置自定义头部布局MaterialHeaderView可见，底部向上滑动时，当滑到页面底部，设置脚部布局MaterialFooterView可见。

事件分发onInterceptTouchEvent中设置头、脚布局可见

在拦截事件onInterceptTouchEvent中，手指移动TouchEvent.POINT_MOVE时，根据滑动距离及是否是在头部的滑动，设置头部自定义headerview是否显示，再根据向上滑动距离是否小于0及是否滑动到底部加载底部footerview。代码如下：

case TouchEvent.POINT_MOVE:
            float currentY = ev.getPointerPosition(0).getY();
            Float dy= new BigDecimal(currentY).subtract(new BigDecimal(mTouchY)).floatValue();
            if (dy > 0 && !canChildScrollUp()) {
                if (mMaterialHeaderView != null) {
                   mMaterialHeaderView.setVisibility(Component.VISIBLE);
                    mMaterialHeaderView.onBegin(this);
                } else if (mSunLayout != null) {
                    mSunLayout.setVisibility(Component.VISIBLE);
                    mSunLayout.onBegin(this);
                }
                return true;
            } else if (dy < 0 && !canChildScrollDown() && isLoadMore) {
                if (mMaterialFooterView != null && !isLoadMoreing) {
                    soveLoadMoreLogic();
                }
                return false;
            }
            break;

上一步完成后，紧接着就是在触摸事件中动态设置头部布局高度，水波纹高度，滑到最大距离时，设置为控件本身高度。

事件触摸onTouchEvent中设置高度

  • 在触摸事件onTouchEvent中，当手指下滑，onTouchEvent中设置头部自定义headerview的高度，随着下滑距离增加，动态设置水波纹高度，当头部为侵入式时，设置component向下平移。代码如下：
case TouchEvent.POINT_MOVE:
            mCurrentY = e.getPointerPosition(0).getY();
            float dy = new BigDecimal(mCurrentY).subtract(new BigDecimal(mTouchY)).floatValue();
            dy = Math.min(mWaveHeight * 2, dy);
            dy = Math.max(0, dy);
            if (mChildView != null) {
                float offsetY = dy / 2;
                float fraction = offsetY / mHeadHeight;
                if (mMaterialHeaderView != null) {
                    mMaterialHeaderView.setHeight((int) offsetY);
                    mMaterialHeaderView.postLayout();
                    mMaterialHeaderView.onPull(this, fraction);
                } else if (mSunLayout != null) {
                    mSunLayout.setHeight((int) offsetY);
                    mSunLayout.postLayout();
                    mSunLayout.startSunLineAnim(this);
                    mSunLayout.onPull(this, fraction);
                }
                if (!isOverlay)
                    mChildView.setTranslationY(offsetY);
            }

在松手时，监听抬起事件TouchEvent.PRIMARY_POINT_UP，当头部headerview高度大于原有高度时，将头部设置为刷新中状态，代码如下：

if (mMaterialHeaderView.getLayoutConfig().height > mHeadHeight) {
    updateListener();
    mMaterialHeaderView.setHeight((int) mHeadHeight);
    mMaterialHeaderView.postLayout();
}

再接下来就是完成自定义头部控件的布局，并在下拉接口方法中设置下拉时的缩放，透明度等状态。

自定义头部MaterialHeaderView

自定义MaterialHeaderView由MaterialWaveView和CircleProgressBar两个自定义Component组合成，实现MaterialHeadListener接口。

  • onBegin方法中设置materialWaveView的起始状态，circleProgressBar缩放大小，透明度等。代码如下：
@Override
public void onBegin(MaterialRefreshLayout materialRefreshLayout) {
    if (materialWaveView != null) {
        materialWaveView.onBegin(materialRefreshLayout);
    }
    if (circleProgressBar != null) {
        circleProgressBar.setScaleX(0.001f);
        circleProgressBar.setScaleY(0.001f);
        circleProgressBar.onBegin(materialRefreshLayout);
    }
 }

onPull方法中设置materialWaveView的下拉状态，circleProgressBar缩放大小，透明度等。代码如下：

@Override
public void onPull(MaterialRefreshLayout materialRefreshLayout, float fraction) {
    if (materialWaveView != null) {
        materialWaveView.onPull(materialRefreshLayout, fraction);
    }
    if (circleProgressBar != null) {
        circleProgressBar.onPull(materialRefreshLayout, fraction);
        float a = Util.limitValue(1, fraction);
        circleProgressBar.setScaleX(a);
        circleProgressBar.setScaleY(a);
        circleProgressBar.setAlpha(a);
    }
}

设置刷新中onRefreshing状态。代码如下：

@Override
public void onRefreshing(MaterialRefreshLayout materialRefreshLayout) {
    if (materialWaveView != null) {
        materialWaveView.onRefreshing(materialRefreshLayout);
    }
    if (circleProgressBar != null) {
        circleProgressBar.onRefreshing(materialRefreshLayout);
    }
}

onComlete刷新完成后自定义Component的状态初始化，代码如下：

@Override
 public void onComlete(MaterialRefreshLayout materialRefreshLayout) {
   if (materialWaveView != null) {
       materialWaveView.onComlete(materialRefreshLayout);
   }
   if (circleProgressBar != null) {
       circleProgressBar.onComlete(materialRefreshLayout);
       circleProgressBar.setTranslationY(0);
       circleProgressBar.setScaleX(0);
       circleProgressBar.setScaleY(0);
  }
}

头部布局完成后，接下来就是实现自定义脚部布局实现。

自定义脚部MaterialFooterView

自定义MaterialFooterView由MaterialWaveView和CircleProgressBar两个自定义Component组合成，实现MaterialHeadListener接口。基本同MaterialHeaderView一致，接口实现方法设置内容相同。

  • onBegin方法中设置materialWaveView的起始状态，circleProgressBar缩放1，透明度等。代码如下：
@Override
public void onBegin(MaterialRefreshLayout materialRefreshLayout) {
    if (materialWaveView != null) {
        materialWaveView.onBegin(materialRefreshLayout);
    }
    if (circleProgressBar != null) {
        circleProgressBar.onBegin(materialRefreshLayout);
        circleProgressBar.setScaleX(1);
        circleProgressBar.setScaleY(1);
    }
}

onPull方法中设置materialWaveView的下拉状态，circleProgressBar缩放1，透明度等。代码如下：

@Override
public void onPull(MaterialRefreshLayout materialRefreshLayout, float fraction) {
    if (materialWaveView != null) {
        materialWaveView.onPull(materialRefreshLayout, fraction);
    }
    if (circleProgressBar != null) {
        circleProgressBar.onPull(materialRefreshLayout, fraction);
        float a = Util.limitValue(1, fraction);
        circleProgressBar.setScaleX(1);
        circleProgressBar.setScaleY(1);
        circleProgressBar.setAlpha(a);
    }
}

设置刷新中onRefreshing状态。代码如下：

@Override
public void onRefreshing(MaterialRefreshLayout materialRefreshLayout) {
    if (materialWaveView != null) {
        materialWaveView.onRefreshing(materialRefreshLayout);
    }
    if (circleProgressBar != null) {
        circleProgressBar.onRefreshing(materialRefreshLayout);
    }
}

onComlete刷新完成后自定义Component的状态初始化，代码如下：####

@Override
public void onComlete(MaterialRefreshLayout materialRefreshLayout) {
    if (materialWaveView != null) {
        materialWaveView.onComlete(materialRefreshLayout);
    }
    if (circleProgressBar != null) {
        circleProgressBar.onComlete(materialRefreshLayout);
        circleProgressBar.setTranslationY(0);
        circleProgressBar.setScaleX(0);
        circleProgressBar.setScaleY(0);
    }
}

头部、脚部布局都完成后，就开始要完成头部和脚部布局里面的自定义组件，首先从头部布局中的自定义组件开始，前面讲到头部由圆形转动条CircleProgressBar和下拉波纹MaterialWaveView组成，先开始绘制波浪纹MaterialWaveView，实现MaterialHeadListener接口，接口回调中设置组件的状态。

自定义MaterialWaveView

  • 初始化画笔设置，添加addDrawTask任务，onDraw方法中绘制下拉区域图形，并填充颜色，代码如下：
@Override
public void onDraw(Component component, Canvas canvas) {
    path.reset();
    paint.setColor(new Color(color));
    path.lineTo(0, headHeight);
    path.quadTo(getEstimatedWidth() / (float) 2, headHeight + waveHeight, getEstimatedWidth(), headHeight);
    path.lineTo(getEstimatedWidth(), 0);
    canvas.drawPath(path, paint);
}

实现MaterialHeadListener接口，监听各下拉方法的回调，当有下拉的情形时，改变下拉区域状态。下拉时在onPull中，设置下拉区域header高度及wave高度。刷新中onRefreshing，加载数值动画并动态改变wave高度。结束onComlete中，加载数值动画动态改变head的高度。代码如下：

  • 下拉时：
@Override
public void onPull(MaterialRefreshLayout br, float fraction) {
    setHeadHeight((int) (Util.dip2px(getContext(), DefaulHeadHeight) * Util.limitValue(1, fraction)));
    setWaveHeight((int) (Util.dip2px(getContext(), DefaulWaveHeight) * Math.max(0, new BigDecimal(fraction).subtract(new BigDecimal(1)).floatValue())));
    invalidate();
}

刷新时：

@Override
public void onRefreshing(MaterialRefreshLayout br) {
    setHeadHeight((int) (Util.dip2px(getContext(), DefaulHeadHeight)));
    int waveHeight = getWaveHeight();
    AnimatorValue animator = new AnimatorValue();
    animator.setValueUpdateListener(new AnimatorValue.ValueUpdateListener() {
        @Override
        public void onUpdate(AnimatorValue animatorValue, float value) {
            setWaveHeight(getIntValue((1 - (double) value) * waveHeight));
            invalidate();
        }
    });
    animator.setCurveType(Animator.CurveType.BOUNCE);
    animator.setDuration(200);
    animator.start();
}

结束时：

@Override
public void onComlete(MaterialRefreshLayout br) {
    waveHeight = 0;
    AnimatorValue animator = new AnimatorValue();
    animator.setDuration(200);
    animator.setValueUpdateListener(new AnimatorValue.ValueUpdateListener() {
        @Override
        public void onUpdate(AnimatorValue animatorValue, float value) {
            headHeight = getIntValue((1 - (double) value) * headHeight);
            invalidate();
        }
    });
    animator.start();
}

上一步完成后接下来开始实现头部圆形转动的CircleProgressBar，并设置图案的自定义ShapeElement图形，配合手势操作，下拉时设置图形动态大小，松手时旋转刷新。

自定义CircleProgressBar

  • 自定义圆形转动CircleProgressBar,设置自定义背景MaterialProgressDrawable，实现MaterialHeadListener接口，根据下拉状态设置圆形MaterialProgressDrawable旋转角度，释放手势时开始动画，结束后停止旋转并初始化状态等。代码如下：
@Override
public void onPull(MaterialRefreshLayout materialRefreshLayout, float fraction) {
    if (mProgressDrawable != null)
        mProgressDrawable.setProgressRotation(fraction);
	invalidate();
}

@Override
Public void onRefreshing(MaterialRefreshLayout materialRefreshLayout) {
    if (mProgressDrawable != null) {
        mProgressDrawable.onStart();
    }
}

@Override
public void onComlete(MaterialRefreshLayout materialRefreshLayout) {
    if (mProgressDrawable != null) {
        mProgressDrawable.onStop();
    }
    setVisibility(Component.INVISIBLE);
}
  • 自定义MaterialProgressDrawable设置CircleProgressBar的背景

首先构造方法中初始化圆形Ring和旋转动画，设置画笔颜色，宽度，大小，在drawToCanvas中绘制圆形Ring, 当有手势操作时调用onStart方法中的旋转动画，开始旋转。在Ring类draw方法中，根据起始旋转角度绘制圆形圈圈及三角箭头，代码如下：

public void draw(Canvas c, Rect bounds) {
        final RectFloat arcBounds = mTempBounds;
        arcBounds.modify(bounds);
        arcBounds.left = new BigDecimal(arcBounds.left).add(new BigDecimal(mStrokeInset)).floatValue();
        arcBounds.top = new BigDecimal(arcBounds.top).add(new BigDecimal(mStrokeInset)).floatValue();
        arcBounds.right = new BigDecimal(arcBounds.right).subtract(new BigDecimal(mStrokeInset)).floatValue();
        arcBounds.bottom = new BigDecimal(arcBounds.bottom).subtract(new BigDecimal(mStrokeInset)).floatValue();

        final float startAngle = new BigDecimal(mStartTrim).add(new BigDecimal(mRotation)).floatValue() * 360;
        final float endAngle = new BigDecimal(mEndTrim).add(new BigDecimal(mRotation)).floatValue() * 360;
        float sweepAngle = new BigDecimal(endAngle).subtract(new BigDecimal(startAngle)).floatValue();

        mPaint.setColor(Color.RED);
        c.drawArc(arcBounds, new Arc(startAngle, sweepAngle, false), mPaint);
        drawTriangle(c, startAngle, sweepAngle, bounds);

        if (mAlpha < 255) {
            mCirclePaint.setColor(new Color(mBackgroundColor));
            mCirclePaint.setAlpha(255 - mAlpha);
            c.drawCircle(bounds.getCenterX(), bounds.getCenterY(), bounds.getWidth() / (float) 2,
                    mCirclePaint);
        }
    }

上述基本上就完成了Material风格下拉刷新带水波纹，带转动progressbar的实现步骤，紧接着讲一讲下拉自定义笑脸的另外一种刷新风格，实际上就是重新定义了刷新头部的图形，在这里也可以自己尝试替换成其它不同的图形。

自定义头部SunLayout布局

自定义头部SunLayout由SunFaceView和SunLineView组成，SunFaceView为自定义笑脸，SunLineView为自定义笑脸周围短线。SunLayout实现了MaterialHeadListener接口，开始状态onBegin时缩放从零到有，下拉onPull时，设置SunView和LineView的大小，缩放等。代码如下：

  • 开始时：
@Override
public void onBegin(MaterialRefreshLayout materialRefreshLayout) {
    setScaleX(0.001f);
    setScaleY(0.001f);
}

下拉时:

@Override
public void onPull(MaterialRefreshLayout materialRefreshLayout, float fraction) {
    float a = Util.limitValue(1, fraction);
    if (a >= 0.7) {
        mLineView.setVisibility(VISIBLE);
    } else {
        mLineView.setVisibility(HIDE);
    }
    mSunView.setPerView(mSunRadius, a);
    mLineView.setLineWidth(mLineWidth);
    setScaleX(a);
    setScaleY(a);
    setAlpha(a);
}
  • 自定义笑脸SunFaceView

继承Component实现Component.EstimateSizeListener, Component.DrawTask接口，onEstimateSize中获取实际宽高，根据宽高onDraw中绘制圆形笑脸，代码如下：

 private void drawCircle(Canvas canvas) {
    mCirclePaint.setColor(new Color(mSunColor));
    mCirclePaint.setStyle(Paint.Style.FILL_STYLE);
    canvas.drawCircle(mWidth / (float) 2, mHeight / (float) 2, mSunRadius, mCirclePaint);
    mCirclePaint.setColor(Color.WHITE);
    if (isDrawFace) {
        mouthRect.left = mWidth / 2 - mSunRadius / 2;
        mouthRect.right = mWidth / 2 + mSunRadius / 2;
        mouthRect.top = mHeight / 2 - mSunRadius / 2;
        mouthRect.bottom = mHeight / 2 + mSunRadius / 2;

        canvas.save();
        canvas.drawCircle(mWidth / 2 - mSunRadius / 2 + mEyesRadius, mHeight / 2 - mSunRadius / 2 + mEyesRadius, mEyesRadius, mCirclePaint);
        canvas.drawCircle(mWidth / 2 + mSunRadius / 2 - mEyesRadius, mHeight / 2 - mSunRadius / 2 + mEyesRadius, mEyesRadius, mCirclePaint);
        mCirclePaint.setStyle(Paint.Style.STROKE_STYLE);
        mCirclePaint.setStrokeWidth(mouthStro);
        canvas.drawArc(mouthRect, new Arc(20, 140, false), mCirclePaint);
        canvas.restore();
    }
}
  • 自定义短线SunLineView

SunLineView继承Component实现Component.DrawTask, Component.EstimateSizeListener接口，构造方法中初始化Paint，onEstimateSize中测量宽高，onDraw中绘制线条，代码如下：

  • 测量时：
@Override
public boolean onEstimateSize(int widthMeasureSpec, int heightMeasureSpec) {
    HiLog.info(Contants.LABEL, "onMeasure");
    int widthMode = EstimateSpec.getMode(widthMeasureSpec);
    int widthSize = EstimateSpec.getSize(widthMeasureSpec);
    int heightMode = EstimateSpec.getMode(heightMeasureSpec);
    int heightSize = EstimateSpec.getSize(heightMeasureSpec);
    int width;
    int height;
    if (widthMode == EstimateSpec.PRECISE) {
        width = widthSize;
    } else {
        width = (mSunRadius + mFixLineHeight + mLineHeight) * 2 + getPaddingRight() + getPaddingLeft();
    }
    if (heightMode == EstimateSpec.PRECISE) {
        height = heightSize;
    } else {
        height = (mSunRadius + mFixLineHeight + mLineHeight) * 2 + getPaddingTop() + getPaddingBottom();
    }
    setEstimatedSize(width, height);
    mWidth = width;
    mHeight = height;
    return false;
}

画线条:

private void drawLines(Canvas canvas) {
    for (int i = 0; i <= 360; i++) {
        if (i % mLineLevel == 0) {
            mLineLeft = mWidth / 2 - mLineWidth / 2;
            mLineTop = mHeight / 2 - mSunRadius - mFixLineHeight;
            mLineBottom = mLineTop + mLineHeight;

           canvas.save();
           canvas.rotate(i, mWidth / (float) 2, mHeight / (float) 2);
           canvas.drawLine(mLineLeft, mLineTop, mLineLeft, mLineBottom, mLinePaint);
           canvas.restore();
     }
 }

}

代码参考

https://gitee.com/chinasoft5_ohos/Ohos-MaterialRefreshLayout

标签：bigdecimalsubtract 

作者:gojiuye , 分类:技术精选 , 浏览:19 , 评论:0

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