长宁网站制作,眉山市住房和城乡建设局网站,电子工程师网名,百度统计怎么用关键计算地方:
1.当前是上滑动还是下滑动(相对于屏幕) ,使用ev.getRawY()获得当前滑动位置在屏幕哪个地方
2. 计算文本客滑动到哪里即可停止, (行高*总文本行数)- (行高 * 最多显示行数) int sum getLineHeight() * getLineCount() - getLineHeight() * getMaxLines();
…关键计算地方:
1.当前是上滑动还是下滑动(相对于屏幕) ,使用ev.getRawY()获得当前滑动位置在屏幕哪个地方
2. 计算文本客滑动到哪里即可停止, (行高*总文本行数)- (行高 * 最多显示行数) int sum getLineHeight() * getLineCount() - getLineHeight() * getMaxLines();
代码
import android.content.Context;
import android.text.method.ScrollingMovementMethod;
import android.util.AttributeSet;
import android.view.MotionEvent;/*** Description: 可滑动的TextView, 并且解决了与 ScrollView等的滑动冲突*/
public class ScrollTextView extends android.support.v7.widget.AppCompatTextView {public ScrollTextView(Context context) {super(context);setMovementMethod(ScrollingMovementMethod.getInstance());}public ScrollTextView(Context context, AttributeSet attrs) {super(context, attrs);setMovementMethod(ScrollingMovementMethod.getInstance());}public ScrollTextView(Context context, AttributeSet attrs, int defStyleAttr) {super(context, attrs, defStyleAttr);setMovementMethod(ScrollingMovementMethod.getInstance());}float lastScrollY 0;Overridepublic boolean onTouchEvent(MotionEvent ev) {if (getLineCount() getMaxLines()) {if (ev.getAction() MotionEvent.ACTION_DOWN) {lastScrollY ev.getRawY();} else if (ev.getAction() MotionEvent.ACTION_MOVE) {//滑动到头并且还在继续上滑动,或者滑动到底部就不要再拦截了(有误差)int sum getLineHeight() * getLineCount() - getLineHeight() * getMaxLines();//计算上次与本次差float diff lastScrollY - ev.getRawY();if (diff0){//下滑动并且到达了底部也不要处理了//底部这里用abs的原因是,因为计算sum的时候有些误差if (Math.abs(sum - getScrollY())5) {getParent().requestDisallowInterceptTouchEvent(false);} else {getParent().requestDisallowInterceptTouchEvent(true);}}else if (diff0){//上滑动if (getScrollY() 0) {//上滑动并且已经到达了顶部就不要在处理了getParent().requestDisallowInterceptTouchEvent(false);} else {getParent().requestDisallowInterceptTouchEvent(true);}}lastScrollY ev.getRawY();} else {getParent().requestDisallowInterceptTouchEvent(false);}}return super.onTouchEvent(ev);}
}如果上面方法不能解决你的问题那就参考下面的文章让textview实现 NestedScroolChild3 接口并重写相应的方法从而实现TextView嵌套滑动。
WebView 实现嵌套滑动丝滑般实现吸顶效果完美兼容 X5 webview
我使用的代码
package com.**.view;
import android.annotation.SuppressLint;
import android.text.StaticLayout;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.text.Layout;
import android.text.TextPaint;
import android.text.method.ScrollingMovementMethod;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.VelocityTracker;
import android.view.View;
import android.view.ViewParent;
import android.widget.OverScroller;
import android.widget.TextView;import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.core.view.NestedScrollingChild3;
import androidx.core.view.NestedScrollingChildHelper;
import androidx.core.view.ViewCompat;public class JustifyTextView extends androidx.appcompat.widget.AppCompatTextView implements NestedScrollingChild3 {private static final String TAG JustifyTextView;private int mLineY;private int mViewWidth;private static final int INVALID_POINTER -1;private final int[] mScrollOffset new int[2];private final int[] mScrollConsumed new int[2];private int mLastMotionY;private NestedScrollingChildHelper mChildHelper;private boolean mIsBeingDragged false;private VelocityTracker mVelocityTracker;private int mTouchSlop;private int mActivePointerId INVALID_POINTER;private int mNestedYOffset;private OverScroller mScroller;private int mMinimumVelocity;private int mMaximumVelocity;private int mLastScrollerY;public JustifyTextView(Context context) {super(context);init();}public JustifyTextView(Context context, AttributeSet attrs) {super(context, attrs);init();}public JustifyTextView(Context context, AttributeSet attrs, int defStyleAttr) {super(context, attrs, defStyleAttr);init();}private void init() {mScroller new OverScroller(getContext());setMovementMethod(ScrollingMovementMethod.getInstance());setOverScrollMode(TextView.OVER_SCROLL_NEVER);mChildHelper new NestedScrollingChildHelper(this);setNestedScrollingEnabled(true);}Overrideprotected void onLayout(boolean changed, int left, int top, int right, int bottom) {super.onLayout(changed, left, top, right, bottom);}Overrideprotected void onDraw(Canvas canvas) {TextPaint paint getPaint();paint.setColor(getCurrentTextColor());// 返回绘制状态的资源ID数组表示视图的当前状态paint.drawableState getDrawableState();// 对View上的内容进行测量后得到的View内容占据的宽度// 前提是你必须在父布局的onLayout()方法或者此View的onDraw()方法里调用measure(0,0);// 否则你得到的结果和getWidth()得到的结果一样。mViewWidth getMeasuredWidth();// 获取文本String text getText().toString();mLineY 0;mLineY getTextSize();// 获取用于显示当前文本的布局Layout layout getLayout();if (layout null) {return;}Paint.FontMetrics fm paint.getFontMetrics();int textHeight (int) (Math.ceil(fm.descent - fm.ascent));textHeight (int) (textHeight * layout.getSpacingMultiplier() layout.getSpacingAdd());for (int i 0; i layout.getLineCount(); i) {// 返回文本中的指定行开头的偏移int lineStart layout.getLineStart(i);// 返回文本中的指定行最后一个字符的偏移int lineEnd layout.getLineEnd(i);float width StaticLayout.getDesiredWidth(text, lineStart, lineEnd, getPaint());String line text.substring(lineStart, lineEnd);if (line.equals()) {break;}if (i layout.getLineCount() - 1) {if (needScale(line)) {drawScaledText(canvas, lineStart, line, width);} else {
// canvas.drawText(line.replace(%, ), 0, mLineY, paint);canvas.drawText(line, 0, mLineY, paint);}} else {canvas.drawText(line, 0, mLineY, paint);}// 增加行高mLineY textHeight;}}private void drawScaledText(Canvas canvas, int lineStart, String line,float lineWidth) {float x 0;if (isFirstLineOfParagraph(lineStart, line)) {String blanks ;canvas.drawText(blanks, x, mLineY, getPaint());float bw StaticLayout.getDesiredWidth(blanks, getPaint());x bw;line line.substring(3);}int gapCount line.length() - 1;int i 0;if (line.length() 2 line.charAt(0) 12288 line.charAt(1) 12288) {String substring line.substring(0, 2);float cw StaticLayout.getDesiredWidth(substring, getPaint());canvas.drawText(substring, x, mLineY, getPaint());x cw;i 2;}float d (mViewWidth - lineWidth) / gapCount;for (; i line.length(); i) {String c String.valueOf(line.charAt(i));float cw StaticLayout.getDesiredWidth(c, getPaint());canvas.drawText(c, x, mLineY, getPaint());x cw d;}}private boolean isFirstLineOfParagraph(int lineStart, String line) {return line.length() 3 line.charAt(0) line.charAt(1) ;}private boolean needScale(String line) {if (line.length() 0) {return false;} else {
// return line.charAt(line.length() - 1) ! %;return line.charAt(line.length() - 1) ! \n;}}SuppressLint(ClickableViewAccessibility)Overridepublic boolean onTouchEvent(MotionEvent ev) {initVelocityTrackerIfNotExists();MotionEvent vtev MotionEvent.obtain(ev);final int actionMasked ev.getActionMasked();if (actionMasked MotionEvent.ACTION_DOWN) {mNestedYOffset 0;}vtev.offsetLocation(0, mNestedYOffset);switch (actionMasked) {case MotionEvent.ACTION_DOWN:if ((mIsBeingDragged !mScroller.isFinished())) {final ViewParent parent getParent();if (parent ! null) {parent.requestDisallowInterceptTouchEvent(true);}}if (!mScroller.isFinished()) {abortAnimatedScroll();}mLastMotionY (int) ev.getY();mActivePointerId ev.getPointerId(0);startNestedScroll(ViewCompat.SCROLL_AXIS_VERTICAL, ViewCompat.TYPE_TOUCH);break;case MotionEvent.ACTION_MOVE:final int activePointerIndex ev.findPointerIndex(mActivePointerId);if (activePointerIndex -1) {Log.e(TAG, Invalid pointerId mActivePointerId in onTouchEvent);break;}final int y (int) ev.getY(activePointerIndex);int deltaY mLastMotionY - y;if (dispatchNestedPreScroll(0, deltaY, mScrollConsumed, mScrollOffset,ViewCompat.TYPE_TOUCH)) {deltaY - mScrollConsumed[1];mNestedYOffset mScrollOffset[1];}if (!mIsBeingDragged Math.abs(deltaY) mTouchSlop) {final ViewParent parent getParent();if (parent ! null) {parent.requestDisallowInterceptTouchEvent(true);}mIsBeingDragged true;if (deltaY 0) {deltaY - mTouchSlop;} else {deltaY mTouchSlop;}}if (mIsBeingDragged) {mLastMotionY y - mScrollOffset[1];final int oldY getScrollY();final int range getScrollRange();// Calling overScrollByCompat will call onOverScrolled, which// calls onScrollChanged if applicable.if (overScrollByCompat(0, deltaY, 0, oldY, 0, range, 0,0, true) !hasNestedScrollingParent(ViewCompat.TYPE_TOUCH)) {mVelocityTracker.clear();}final int scrolledDeltaY getScrollY() - oldY;final int unconsumedY deltaY - scrolledDeltaY;mScrollConsumed[1] 0;dispatchNestedScroll(0, scrolledDeltaY, 0, unconsumedY, mScrollOffset,ViewCompat.TYPE_TOUCH, mScrollConsumed);mLastMotionY - mScrollOffset[1];mNestedYOffset mScrollOffset[1];}break;case MotionEvent.ACTION_UP:final VelocityTracker velocityTracker mVelocityTracker;velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);int initialVelocity (int) velocityTracker.getYVelocity(mActivePointerId);if ((Math.abs(initialVelocity) mMinimumVelocity)) {if (!dispatchNestedPreFling(0, -initialVelocity)) {dispatchNestedFling(0, -initialVelocity, true);fling(-initialVelocity);}} else if (mScroller.springBack(getScrollX(), getScrollY(), 0, 0, 0,getScrollRange())) {ViewCompat.postInvalidateOnAnimation(this);}mActivePointerId INVALID_POINTER;endDrag();break;case MotionEvent.ACTION_CANCEL:if (mIsBeingDragged) {if (mScroller.springBack(getScrollX(), getScrollY(), 0, 0, 0,getScrollRange())) {ViewCompat.postInvalidateOnAnimation(this);}}mActivePointerId INVALID_POINTER;endDrag();break;case MotionEvent.ACTION_POINTER_DOWN:final int index ev.getActionIndex();mLastMotionY (int) ev.getY(index);mActivePointerId ev.getPointerId(index);break;case MotionEvent.ACTION_POINTER_UP:onSecondaryPointerUp(ev);mLastMotionY (int) ev.getY(ev.findPointerIndex(mActivePointerId));break;}if (mVelocityTracker ! null) {mVelocityTracker.addMovement(vtev);}vtev.recycle();return super.onTouchEvent(ev);}private void abortAnimatedScroll() {mScroller.abortAnimation();stopNestedScroll(ViewCompat.TYPE_NON_TOUCH);}private void endDrag() {mIsBeingDragged false;recycleVelocityTracker();stopNestedScroll();}private void onSecondaryPointerUp(MotionEvent ev) {final int pointerIndex (ev.getAction() MotionEvent.ACTION_POINTER_INDEX_MASK) MotionEvent.ACTION_POINTER_INDEX_SHIFT;final int pointerId ev.getPointerId(pointerIndex);if (pointerId mActivePointerId) {final int newPointerIndex pointerIndex 0 ? 1 : 0;mLastMotionY (int) ev.getY(newPointerIndex);mActivePointerId ev.getPointerId(newPointerIndex);if (mVelocityTracker ! null) {mVelocityTracker.clear();}}}private void fling(int velocityY) {int height getHeight();mScroller.fling(getScrollX(), getScrollY(), // start0, velocityY, // velocities0, 0, // xInteger.MIN_VALUE, Integer.MAX_VALUE, // y0, height / 2);runAnimatedScroll(true);}private void runAnimatedScroll(boolean participateInNestedScrolling) {if (participateInNestedScrolling) {startNestedScroll(ViewCompat.SCROLL_AXIS_VERTICAL, ViewCompat.TYPE_NON_TOUCH);} else {stopNestedScroll(ViewCompat.TYPE_NON_TOUCH);}mLastScrollerY getScrollY();ViewCompat.postInvalidateOnAnimation(this);}private void initOrResetVelocityTracker() {if (mVelocityTracker null) {mVelocityTracker VelocityTracker.obtain();} else {mVelocityTracker.clear();}}private void initVelocityTrackerIfNotExists() {if (mVelocityTracker null) {mVelocityTracker VelocityTracker.obtain();}}private void recycleVelocityTracker() {if (mVelocityTracker ! null) {mVelocityTracker.recycle();mVelocityTracker null;}}Overrideprotected boolean overScrollBy(int deltaX, int deltaY,int scrollX, int scrollY,int scrollRangeX, int scrollRangeY,int maxOverScrollX, int maxOverScrollY,boolean isTouchEvent) {// this is causing double scroll call (doubled speed), but this WebView isnt overscrollable// all overscrolls are passed to appbar, so commenting this out during dragif (!mIsBeingDragged)overScrollByCompat(deltaX, deltaY, scrollX, scrollY, scrollRangeX, scrollRangeY,maxOverScrollX, maxOverScrollY, isTouchEvent);// without this call webview wont scroll to top when url change or when user pick input// (webview should move a bit making input still in viewport when adjustResize)return true;}int getScrollRange() {//Using scroll range of webview instead of childs as NestedScrollView does.return computeVerticalScrollRange();}Overridepublic boolean isNestedScrollingEnabled() {return mChildHelper.isNestedScrollingEnabled();}Overridepublic void setNestedScrollingEnabled(boolean enabled) {mChildHelper.setNestedScrollingEnabled(enabled);}Overridepublic boolean startNestedScroll(int axes, int type) {return mChildHelper.startNestedScroll(axes, type);}Overridepublic boolean startNestedScroll(int axes) {return startNestedScroll(axes, ViewCompat.TYPE_TOUCH);}Overridepublic void stopNestedScroll(int type) {mChildHelper.stopNestedScroll(type);}Overridepublic void stopNestedScroll() {stopNestedScroll(ViewCompat.TYPE_TOUCH);}Overridepublic boolean hasNestedScrollingParent(int type) {return mChildHelper.hasNestedScrollingParent(type);}Overridepublic boolean hasNestedScrollingParent() {return hasNestedScrollingParent(ViewCompat.TYPE_TOUCH);}Overridepublic boolean dispatchNestedScroll(int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed,int[] offsetInWindow) {return dispatchNestedScroll(dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed,offsetInWindow, ViewCompat.TYPE_TOUCH);}Overridepublic boolean dispatchNestedScroll(int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed,int[] offsetInWindow, int type) {return mChildHelper.dispatchNestedScroll(dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed,offsetInWindow, type);}Overridepublic void dispatchNestedScroll(int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed,Nullable int[] offsetInWindow, int type, NonNull int[] consumed) {mChildHelper.dispatchNestedScroll(dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed,offsetInWindow, type, consumed);}Overridepublic boolean dispatchNestedPreScroll(int dx, int dy, int[] consumed, int[] offsetInWindow) {return dispatchNestedPreScroll(dx, dy, consumed, offsetInWindow, ViewCompat.TYPE_TOUCH);}Overridepublic boolean dispatchNestedPreScroll(int dx, int dy, int[] consumed, int[] offsetInWindow, int type) {return mChildHelper.dispatchNestedPreScroll(dx, dy, consumed, offsetInWindow, type);}Overridepublic boolean dispatchNestedFling(float velocityX, float velocityY, boolean consumed) {return mChildHelper.dispatchNestedFling(velocityX, velocityY, false);}Overridepublic boolean dispatchNestedPreFling(float velocityX, float velocityY) {return mChildHelper.dispatchNestedPreFling(velocityX, velocityY);}Overridepublic void computeScroll() {if (mScroller.isFinished()) {return;}mScroller.computeScrollOffset();final int y mScroller.getCurrY();int unconsumed y - mLastScrollerY;mLastScrollerY y;// Nested Scrolling Pre PassmScrollConsumed[1] 0;dispatchNestedPreScroll(0, unconsumed, mScrollConsumed, null,ViewCompat.TYPE_NON_TOUCH);unconsumed - mScrollConsumed[1];if (unconsumed ! 0) {// Internal Scrollfinal int oldScrollY getScrollY();overScrollByCompat(0, unconsumed, getScrollX(), oldScrollY, 0, getScrollRange(),0, 0, false);final int scrolledByMe getScrollY() - oldScrollY;unconsumed - scrolledByMe;// Nested Scrolling Post PassmScrollConsumed[1] 0;dispatchNestedScroll(0, 0, 0, unconsumed, mScrollOffset,ViewCompat.TYPE_NON_TOUCH, mScrollConsumed);unconsumed - mScrollConsumed[1];}if (unconsumed ! 0) {abortAnimatedScroll();}if (!mScroller.isFinished()) {ViewCompat.postInvalidateOnAnimation(this);}}// copied from NestedScrollView exacly as it looks, leaving overscroll related code, maybe future useprivate boolean overScrollByCompat(int deltaX, int deltaY,int scrollX, int scrollY,int scrollRangeX, int scrollRangeY,int maxOverScrollX, int maxOverScrollY,boolean isTouchEvent) {final int overScrollMode getOverScrollMode();final boolean canScrollHorizontal computeHorizontalScrollRange() computeHorizontalScrollExtent();final boolean canScrollVertical computeVerticalScrollRange() computeVerticalScrollExtent();final boolean overScrollHorizontal overScrollMode View.OVER_SCROLL_ALWAYS|| (overScrollMode View.OVER_SCROLL_IF_CONTENT_SCROLLS canScrollHorizontal);final boolean overScrollVertical overScrollMode View.OVER_SCROLL_ALWAYS|| (overScrollMode View.OVER_SCROLL_IF_CONTENT_SCROLLS canScrollVertical);int newScrollX scrollX deltaX;if (!overScrollHorizontal) {maxOverScrollX 0;}int newScrollY scrollY deltaY;if (!overScrollVertical) {maxOverScrollY 0;}// Clamp values if at the limits and recordfinal int left -maxOverScrollX;final int right maxOverScrollX scrollRangeX;final int top -maxOverScrollY;final int bottom maxOverScrollY scrollRangeY;boolean clampedX false;if (newScrollX right) {newScrollX right;clampedX true;} else if (newScrollX left) {newScrollX left;clampedX true;}boolean clampedY false;if (newScrollY bottom) {newScrollY bottom;clampedY true;} else if (newScrollY top) {newScrollY top;clampedY true;}if (clampedY !hasNestedScrollingParent(ViewCompat.TYPE_NON_TOUCH)) {mScroller.springBack(newScrollX, newScrollY, 0, 0, 0, getScrollRange());}onOverScrolled(newScrollX, newScrollY, clampedX, clampedY);return clampedX || clampedY;}
}
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定时垂直滚动的textviewGitHub - paradoxie/AutoVerticalTextview: 垂直滚动的textview继承自TextSwitcher抽出一个依赖库供以后备用
左右对齐的TextView
GitHub - Giftedcat/JustifyTextView: 左右对齐的TextView适配各种分辨率完美实现UI需求 JustifyTextView 自定义TextView解决中文排版-CSDN博客
