Tap to refresh is visible all the time and gap is still visible on list view

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无人共我
无人共我 2021-02-11 11:05

I am using pull to refresh in my application. Pull to refresh is working fine when the list size is crossing screen. But when the size is one or two there is a gap between the h

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  • 2021-02-11 11:11

    Use this code instead

    public class PullToRefreshListView extends ListView implements OnScrollListener {
    
    //  private static final int TAP_TO_REFRESH = 1;
    private static final int PULL_TO_REFRESH = 2;
    private static final int RELEASE_TO_REFRESH = 3;
    protected static final int REFRESHING = 4;
    
    protected static final String TAG = "PullToRefreshListView";
    
    private OnRefreshListener mOnRefreshListener;
    
    /**
     * Listener that will receive notifications every time the list scrolls.
     */
    private OnScrollListener mOnScrollListener;
    protected LayoutInflater mInflater;
    
    // header
    private RelativeLayout mRefreshView;
    private TextView mRefreshViewText;
    private ImageView mRefreshViewImage;
    private ProgressBar mRefreshViewProgress;
    private TextView mRefreshViewLastUpdated;
    
    protected int mCurrentScrollState;
    protected int mRefreshState;
    
    private RotateAnimation mFlipAnimation;
    private RotateAnimation mReverseFlipAnimation;
    
    private int mRefreshViewHeight;
    private int mRefreshOriginalTopPadding;
    private int mLastMotionY;
    
    private boolean mBounceHack;
    
    public PullToRefreshListView(Context context) {
        super(context);
        init(context);
    }
    
    public PullToRefreshListView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(context);
    }
    
    public PullToRefreshListView(Context context, AttributeSet attrs,
            int defStyle) {
        super(context, attrs, defStyle);
        init(context);
    }
    
    protected void init(Context context) {
        // Load all of the animations we need in code rather than through XML
        mFlipAnimation = new RotateAnimation(0, -180,
                RotateAnimation.RELATIVE_TO_SELF, 0.5f,
                RotateAnimation.RELATIVE_TO_SELF, 0.5f);
        mFlipAnimation.setInterpolator(new LinearInterpolator());
        mFlipAnimation.setDuration(250);
        mFlipAnimation.setFillAfter(true);
        mReverseFlipAnimation = new RotateAnimation(-180, 0,
                RotateAnimation.RELATIVE_TO_SELF, 0.5f,
                RotateAnimation.RELATIVE_TO_SELF, 0.5f);
        mReverseFlipAnimation.setInterpolator(new LinearInterpolator());
        mReverseFlipAnimation.setDuration(250);
        mReverseFlipAnimation.setFillAfter(true);
    
        mInflater = (LayoutInflater) context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    
        // header
        mRefreshView = (RelativeLayout) mInflater.inflate(
                R.layout.pull_to_refresh_header, this, false);
        mRefreshViewText = (TextView) mRefreshView
                .findViewById(R.id.pull_to_refresh_text);
        mRefreshViewImage = (ImageView) mRefreshView
                .findViewById(R.id.pull_to_refresh_image);
        mRefreshViewProgress = (ProgressBar) mRefreshView
                .findViewById(R.id.pull_to_refresh_progress);
        mRefreshViewLastUpdated = (TextView) mRefreshView
                .findViewById(R.id.pull_to_refresh_updated_at);
    
        mRefreshViewImage.setMinimumHeight(50);
        mRefreshView.setOnClickListener(new OnClickRefreshListener());
        mRefreshOriginalTopPadding = mRefreshView.getPaddingTop();
    
        mRefreshState = PULL_TO_REFRESH;
    
        addHeaderView(mRefreshView);
    
        super.setOnScrollListener(this);
    
        measureView(mRefreshView);
        mRefreshViewHeight = mRefreshView.getMeasuredHeight();
    }
    
    @Override
    protected void onAttachedToWindow() {
        //have to ask super to attach to window, otherwise it won't scroll in jelly bean.
        super.onAttachedToWindow();
        setSelection(1);
    }
    
    @Override
    public void setAdapter(ListAdapter adapter) {
        super.setAdapter(adapter);
    
        setSelection(1);
    }
    
    /**
     * Set the listener that will receive notifications every time the list
     * scrolls.
     * 
     * @param l
     *            The scroll listener.
     */
    @Override
    public void setOnScrollListener(AbsListView.OnScrollListener l) {
        mOnScrollListener = l;
    }
    
    /**
     * Register a callback to be invoked when this list should be refreshed.
     * 
     * @param onRefreshListener
     *            The callback to run.
     */
    public void setOnRefreshListener(OnRefreshListener onRefreshListener) {
        mOnRefreshListener = onRefreshListener;
    }
    
    /**
     * Set a text to represent when the list was last updated.
     * 
     * @param lastUpdated
     *            Last updated at.
     */
    public void setLastUpdated(CharSequence lastUpdated) {
        if (lastUpdated != null) {
            mRefreshViewLastUpdated.setVisibility(View.VISIBLE);
            mRefreshViewLastUpdated.setText(lastUpdated);
        } else {
            mRefreshViewLastUpdated.setVisibility(View.GONE);
        }
    }
    
    @SuppressLint("ClickableViewAccessibility")
    @Override
    public boolean onTouchEvent(MotionEvent event) {
        final int y = (int) event.getY();
        mBounceHack = false;
    
        switch (event.getAction()) {
        case MotionEvent.ACTION_UP:
            if (!isVerticalScrollBarEnabled()) {
                setVerticalScrollBarEnabled(true);
            }
            if (getFirstVisiblePosition() == 0 && mRefreshState != REFRESHING) {
                if ((mRefreshView.getBottom() >= mRefreshViewHeight || mRefreshView
                        .getTop() >= 0) && mRefreshState == RELEASE_TO_REFRESH) {
                    // Initiate the refresh
                    mRefreshState = REFRESHING;
                    prepareForRefresh();
                    onRefresh();
                } else if (mRefreshView.getBottom() < mRefreshViewHeight
                        || mRefreshView.getTop() <= 0) {
                    // Abort refresh and scroll down below the refresh view
                    resetHeader();
                    setSelection(1);
                }
            }
            break;
        case MotionEvent.ACTION_DOWN:
            mLastMotionY = y;
            break;
        case MotionEvent.ACTION_MOVE:
            applyHeaderPadding(event);
            break;
        }
        return super.onTouchEvent(event);
    }
    
    private void applyHeaderPadding(MotionEvent ev) {
        // getHistorySize has been available since API 1
        int pointerCount = ev.getHistorySize();
    
        for (int p = 0; p < pointerCount; p++) {
    //          if (mRefreshState == RELEASE_TO_REFRESH) {
                if (isVerticalFadingEdgeEnabled()) {
                    setVerticalScrollBarEnabled(false);
                }
    
                int historicalY = (int) ev.getHistoricalY(p);
    
                // Calculate the padding to apply, we divide by 1.7 to
                // simulate a more resistant effect during pull.
                int topPadding = (int) (((historicalY - mLastMotionY) - mRefreshViewHeight) / 1.7);
    
                mRefreshView.setPadding(mRefreshView.getPaddingLeft(),
                        topPadding, mRefreshView.getPaddingRight(),
                        mRefreshView.getPaddingBottom());
            }
    //      }
    }
    
    /**
     * Sets the header padding back to original size.
     */
    private void resetHeaderPadding() {
        mLastMotionY = 0;
        mRefreshView.setPadding(mRefreshView.getPaddingLeft(),
                mRefreshOriginalTopPadding, mRefreshView.getPaddingRight(),
                mRefreshView.getPaddingBottom());
    }
    
    /**
     * Resets the header to the original state.
     */
    private void resetHeader() {
    //      if (mRefreshState != TAP_TO_REFRESH) {
            mRefreshState = PULL_TO_REFRESH;
    
            resetHeaderPadding();
    
            // Set refresh view text to the pull label
            mRefreshViewText.setText(R.string.pull_to_refresh_tap_label);
            // Replace refresh drawable with arrow drawable
            mRefreshViewImage
                    .setImageResource(R.drawable.ic_pulltorefresh_arrow);
            // Clear the full rotation animation
            mRefreshViewImage.clearAnimation();
            // Hide progress bar and arrow.
            mRefreshViewImage.setVisibility(View.GONE);
            mRefreshViewProgress.setVisibility(View.GONE);
    //      }
    }
    
    private void measureView(View child) {
        ViewGroup.LayoutParams p = child.getLayoutParams();
        if (p == null) {
            p = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.FILL_PARENT,
                    ViewGroup.LayoutParams.WRAP_CONTENT);
        }
    
        int childWidthSpec = ViewGroup.getChildMeasureSpec(0, 0 + 0, p.width);
        int lpHeight = p.height;
        int childHeightSpec;
        if (lpHeight > 0) {
            childHeightSpec = MeasureSpec.makeMeasureSpec(lpHeight,
                    MeasureSpec.EXACTLY);
        } else {
            childHeightSpec = MeasureSpec.makeMeasureSpec(0,
                    MeasureSpec.UNSPECIFIED);
        }
        child.measure(childWidthSpec, childHeightSpec);
    }
    
    public void onScroll(AbsListView view, int firstVisibleItem,
            int visibleItemCount, int totalItemCount) {
        // When the refresh view is completely visible, change the text to say
        // "Release to refresh..." and flip the arrow drawable.
        if (mCurrentScrollState == SCROLL_STATE_TOUCH_SCROLL
                && mRefreshState != REFRESHING) {
            if (firstVisibleItem == 0) {
                mRefreshViewImage.setVisibility(View.VISIBLE);
                if ((mRefreshView.getBottom() >= mRefreshViewHeight + 20 || mRefreshView
                        .getTop() >= 0) && mRefreshState != RELEASE_TO_REFRESH) {
                    mRefreshViewText
                            .setText(R.string.pull_to_refresh_release_label);
                    mRefreshViewImage.clearAnimation();
                    mRefreshViewImage.startAnimation(mFlipAnimation);
                    mRefreshState = RELEASE_TO_REFRESH;
                } else if (mRefreshView.getBottom() < mRefreshViewHeight + 20
                        && mRefreshState != PULL_TO_REFRESH) {
                    mRefreshViewText
                            .setText(R.string.pull_to_refresh_pull_label);
    //                  if (mRefreshState != TAP_TO_REFRESH) {
                        mRefreshViewImage.clearAnimation();
                        mRefreshViewImage.startAnimation(mReverseFlipAnimation);
    //                  }
                    mRefreshState = PULL_TO_REFRESH;
                }
            } else {
                mRefreshViewImage.setVisibility(View.GONE);
                resetHeader();
            }
        } else if (mCurrentScrollState == SCROLL_STATE_FLING
                && firstVisibleItem == 0 && mRefreshState != REFRESHING) {
            setSelection(1);
            mBounceHack = true;
        } else if (mBounceHack && mCurrentScrollState == SCROLL_STATE_FLING) {
            setSelection(1);
        }
    
        if (mOnScrollListener != null) {
            mOnScrollListener.onScroll(view, firstVisibleItem,
                    visibleItemCount, totalItemCount);
        }
    }
    
    public void onScrollStateChanged(AbsListView view, int scrollState) {
        mCurrentScrollState = scrollState;
    
        if (mCurrentScrollState == SCROLL_STATE_IDLE) {
            mBounceHack = false;
        }
    
        if (mOnScrollListener != null) {
            mOnScrollListener.onScrollStateChanged(view, scrollState);
        }
    
    }
    
    public void prepareForRefresh() {
        resetHeaderPadding();
    
        mRefreshViewImage.setVisibility(View.GONE);
        // We need this hack, otherwise it will keep the previous drawable.
        mRefreshViewImage.setImageDrawable(null);
        mRefreshViewProgress.setVisibility(View.VISIBLE);
    
        // Set refresh view text to the refreshing label
        mRefreshViewText.setText(R.string.pull_to_refresh_refreshing_label);
    
        mRefreshState = REFRESHING;
    }
    
    public void onRefresh() {
        Log.d(TAG, "onRefresh");
    
        if (mOnRefreshListener != null) {
            mOnRefreshListener.onRefresh();
        }
    }
    
    /**
     * Resets the list to a normal state after a refresh.
     * 
     * @param lastUpdated
     *            Last updated at.
     */
    public void onRefreshComplete(CharSequence lastUpdated) {
        setLastUpdated(lastUpdated);
        onRefreshComplete();
    }
    
    /**
     * Resets the list to a normal state after a refresh.
     */
    public void onRefreshComplete() {
        Log.d(TAG, "onRefreshComplete");
    
        resetHeader();
    
        // If refresh view is visible when loading completes, scroll down to
        // the next item.
        if (mRefreshView.getBottom() > 0) {
            invalidateViews();
            setSelection(1);
        }
    }
    
    /**
     * Invoked when the refresh view is clicked on. This is mainly used when
     * there's only a few items in the list and it's not possible to drag the
     * list.
     */
    private class OnClickRefreshListener implements OnClickListener {
    
        public void onClick(View v) {
            if (mRefreshState != REFRESHING) {
                prepareForRefresh();
                onRefresh();
            }
        }
    
    }
    
    /**
     * Interface definition for a callback to be invoked when list should be
     * refreshed.
     */
    public interface OnRefreshListener {
        /**
         * Called when the list should be refreshed.
         * <p>
         * A call to {@link PullToRefreshListView #onRefreshComplete()} is
         * expected to indicate that the refresh has completed.
         */
        public void onRefresh();
    }
    
    }
    

    also set the visibility to gone in the pull_to_refresh_header.xml in your library layout if you have it (android:id="@+id/pull_to_refresh_text")

    <TextView
        android:id="@+id/pull_to_refresh_text"
        android:text="@string/pull_to_refresh_pull_label"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:textStyle="bold"
        android:paddingTop="5dip"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:gravity="center"
        android:visibility="gone"
        />
    

    enjoy!

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