<LinearLayout android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical"> <com.wiggins.expandable.widget.MoreLineTextView  android:id="@+id/tv_more_line_short"  android:layout_width="match_parent"  android:layout_height="wrap_content"  android:background="@color/white"  android:padding="@dimen/padding_small"  app:clickAll="true"  app:textColor="@color/red" /> <View style="@style/spaceLine" /> <com.wiggins.expandable.widget.expandable.ExpandableTextView  android:id="@+id/tv_expandable_short"  android:layout_width="match_parent"  android:layout_height="wrap_content"  android:background="@color/white"  android:ellipsize="end"  android:padding="@dimen/padding_small"  android:textColor="@color/blue"  app:allClickable="false"  app:contentTextColor="@color/blue"  app:isDisplayIcon="false"  app:maxCollapsedLines="4" /> <View style="@style/spaceLine" /> <com.wiggins.expandable.widget.MoreLineTextView  android:id="@+id/tv_more_line_long"  android:layout_width="match_parent"  android:layout_height="wrap_content"  android:background="@color/white"  android:padding="@dimen/padding_small"  app:clickAll="true"  app:textColor="@color/red" /> <View style="@style/spaceLine" /> <com.wiggins.expandable.widget.expandable.ExpandableTextView  android:id="@+id/tv_expandable_long"  android:layout_width="match_parent"  android:layout_height="wrap_content"  android:background="@color/white"  android:ellipsize="end"  android:padding="@dimen/padding_small"  android:textColor="@color/blue"  app:allClickable="false"  app:contentTextColor="@color/blue"  app:isDisplayIcon="false"  app:maxCollapsedLines="4" /></LinearLayout>

private void initData() { mTvMoreLineShort.setText(Constant.content1); mTvExpandableShort.setText(Constant.content2); mTvMoreLineLong.setText(Constant.content3); mTvExpandableLong.setText(Constant.content4);}

<declare-styleable name="MoreTextStyle"> <!--內容大小--> <attr name="textSize" format="dimension" /> <!--內容顏色--> <attr name="textColor" format="color" /> <!--內容默認最大行數--> <attr name="maxLine" format="integer" /> <!--展開/收起圖標--> <attr name="expandIcon" format="reference" /> <!--展開/收起動畫執行時間--> <attr name="durationMillis" format="integer" /> <!--可點擊區域，默認展開/收起區域可點擊--> <attr name="clickAll" format="boolean" /></declare-styleable>

@Overrideprotected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); // 如果沒有變化，測量并返回 if (!mRelayout || getVisibility() == View.GONE) {  super.onMeasure(widthMeasureSpec, heightMeasureSpec);  return; } mRelayout = false; super.onMeasure(widthMeasureSpec, heightMeasureSpec); // 內容區域初始顯示行高 mTvContent.setHeight(mTvContent.getLineHeight() * (mMaxLine > mTvContent.getLineCount() ? mTvContent.getLineCount() : mMaxLine)); mLlExpand.post(new Runnable() {  @Override  public void run() {   // 是否顯示折疊效果   mLlExpand.setVisibility(mTvContent.getLineCount() > mMaxLine ? View.VISIBLE : View.GONE);  } });}

/** * @Description 設置顯示內容 */public void setText(String str) { mRelayout = true; mTvContent.setText(str); setVisibility(TextUtils.isEmpty(str) ? View.GONE : View.VISIBLE);}

@Overridepublic void onClick(View v) { if (mTvContent.getLineCount() <= mMaxLine) {  return; } isExpand = !isExpand; mTvContent.clearAnimation(); final int deltaValue; final int startValue = mTvContent.getHeight(); if (isExpand) {  deltaValue = mTvContent.getLineHeight() * mTvContent.getLineCount() - startValue;//計算要展開高度  RotateAnimation animation = new RotateAnimation(0, 180, Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 0.5f);  animation.setDuration(mDurationMillis);  animation.setFillAfter(true);  mIvExpand.startAnimation(animation);  mTvExpand.setText(getContext().getString(R.string.collapse)); } else {  deltaValue = mTvContent.getLineHeight() * mMaxLine - startValue;//為負值，收縮的高度  RotateAnimation animation = new RotateAnimation(180, 0, Animation.RELATIVE_TO_SELF, 0.5f, Animation.RELATIVE_TO_SELF, 0.5f);  animation.setDuration(mDurationMillis);  animation.setFillAfter(true);  mIvExpand.startAnimation(animation);  mTvExpand.setText(getContext().getString(R.string.expand)); } Animation animation = new Animation() {  protected void applyTransformation(float interpolatedTime, Transformation t) {   //interpolatedTime:為當前動畫幀對應的相對時間，值總在0-1之間,原始長度+高度差*（從0到1的漸變）即表現為動畫效果   mTvContent.setHeight((int) (startValue + deltaValue * interpolatedTime));  } }; animation.setDuration(mDurationMillis); mTvContent.startAnimation(animation);}

<declare-styleable name="ExpandableTextView"> <!--內容默認最大行數，超過隱藏--> <attr name="maxCollapsedLines" format="integer" /> <!--展開/收起動畫執行時間--> <attr name="animDuration" format="integer" /> <!--展開圖片--> <attr name="expandDrawable" format="reference" /> <!--收起圖片--> <attr name="collapseDrawable" format="reference" /> <!--內容顏色--> <attr name="contentTextColor" format="color" /> <!--內容大小--> <attr name="contentTextSize" format="dimension" /> <!--收起/展開顏色--> <attr name="collapseExpandTextColor" format="color" /> <!--收起/展開大小--> <attr name="collapseExpandTextSize" format="dimension" /> <!--收起文字--> <attr name="textCollapse" format="string" /> <!--展開文字--> <attr name="textExpand" format="string" /> <!--可點擊區域，默認展開/收起區域可點擊--> <attr name="allClickable" format="boolean" /> <!--是否顯示展開/收起圖標，默認顯示--> <attr name="isDisplayIcon" format="boolean" /> <!--收起/展開位置，默認左邊--> <attr name="collapseExpandGrarity">  <flag name="left" value="3" />  <flag name="right" value="5" /> </attr> <!--收起/展開圖標位置，默認右邊--> <attr name="drawableGrarity">  <flag name="left" value="3" />  <flag name="right" value="5" /> </attr></declare-styleable>

@Overrideprotected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { // 如果沒有變化，測量并返回 if (!mRelayout || getVisibility() == View.GONE) {  super.onMeasure(widthMeasureSpec, heightMeasureSpec);  return; } mRelayout = false; // Setup with optimistic case // i.e. Everything fits. No button needed mLlExpand.setVisibility(View.GONE); mTvContent.setMaxLines(Integer.MAX_VALUE); // Measure super.onMeasure(widthMeasureSpec, heightMeasureSpec); //如果內容真實行數小于等于最大行數，不處理 if (mTvContent.getLineCount() <= mMaxCollapsedLines) {  return; } // 獲取內容tv真實高度（含padding） mTextHeightWithMaxLines = getRealTextViewHeight(mTvContent); // 如果是收起狀態，重新設置最大行數 if (mCollapsed) {  mTvContent.setMaxLines(mMaxCollapsedLines); } mLlExpand.setVisibility(View.VISIBLE); // Re-measure with new setup super.onMeasure(widthMeasureSpec, heightMeasureSpec); if (mCollapsed) {  // Gets the margin between the TextView's bottom and the ViewGroup's bottom  mTvContent.post(new Runnable() {   @Override   public void run() {    mMarginBetweenTxtAndBottom = getHeight() - mTvContent.getHeight();   }  });  // 保存這個容器的測量高度  mCollapsedHeight = getMeasuredHeight(); }}

/** * @Description 設置顯示內容 */public void setText(CharSequence text) { mRelayout = true; mTvContent.setText(text); setVisibility(TextUtils.isEmpty(text) ? View.GONE : View.VISIBLE);}

@Overridepublic void onClick(View view) { if (mLlExpand.getVisibility() != View.VISIBLE) {  return; } mCollapsed = !mCollapsed; // 修改收起/展開圖標、文字 setDrawbleAndText(); // 保存位置狀態 if (mCollapsedStatus != null) {  mCollapsedStatus.put(mPosition, mCollapsed); } // 執行展開/收起動畫 mAnimating = true; ValueAnimator valueAnimator; if (mCollapsed) {  valueAnimator = new ValueAnimator().ofInt(getHeight(), mCollapsedHeight); } else {  mCollapsedHeight = getHeight();  valueAnimator = new ValueAnimator().ofInt(getHeight(), getHeight() + mTextHeightWithMaxLines - mTvContent.getHeight()); } valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {  @Override  public void onAnimationUpdate(ValueAnimator valueAnimator) {   int animatedValue = (int) valueAnimator.getAnimatedValue();   mTvContent.setMaxHeight(animatedValue - mMarginBetweenTxtAndBottom);   getLayoutParams().height = animatedValue;   requestLayout();  } }); valueAnimator.addListener(new Animator.AnimatorListener() {  @Override  public void onAnimationStart(Animator animator) {  }  @Override  public void onAnimationEnd(Animator animator) {   // 動畫結束后發送結束的信號，清除動畫標志   mAnimating = false;   // 通知監聽   if (mListener != null) {    mListener.onExpandStateChanged(mTvContent, !mCollapsed);   }  }  @Override  public void onAnimationCancel(Animator animator) {  }  @Override  public void onAnimationRepeat(Animator animator) {  } }); valueAnimator.setDuration(mAnimationDuration); valueAnimator.start();}