Android 滑動Scrollview標題欄漸變效果(仿京東toolbar)

Posted on by

Scrollview標題欄滑動漸變

仿京東樣式(上滑顯示下滑漸變消失)

在這裡插入圖片描述

在這裡插入圖片描述

/**
 * @ClassName MyScrollView
 * @Author Rex
 * @Date 2021/1/27 17:38
 */
public class MyScrollView extends ScrollView {
 private TranslucentListener mTranslucentListener;

 public void setTranslucentListener(TranslucentListener translucentListener) {
  this.mTranslucentListener = translucentListener;
 }
 public MyScrollView(Context context) {
  this(context, null);
 }

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

 public MyScrollView(Context context, AttributeSet attrs, int defStyleAttr) {
  this(context, attrs, defStyleAttr, 0);
 }

 public MyScrollView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
  super(context, attrs, defStyleAttr, defStyleRes);
 }

 @Override
 protected void onScrollChanged(int l, int t, int oldl, int oldt) {
  super.onScrollChanged(l, t, oldl, oldt);
  if (mTranslucentListener != null) {
   //ScrollView滑出高度
   int scrollY = getScrollY();
   //屏幕高度
   int screenHeight = getContext().getResources().getDisplayMetrics().heightPixels;
   //有效滑動距離為屏幕2分之一
   // alpha = 滑動高度/（screenHeight/3f）
   if (scrollY <= screenHeight / 2f) {
    Log.d(">>>>>>>>>", "ScrollView劃出高度：" + scrollY);
    Log.d(">>>>>>>>>", "屏幕高度：" + screenHeight);
    Log.d(">>>>>>>>>", "漸變值：" + (0 + scrollY / (screenHeight / 4f)));
    // 漸變的過程 1~0
    mTranslucentListener.onTranslucent(0 + scrollY / (screenHeight /4f));
   }
  }
 }
}

Activity 設置

public class ToolbarActivity extends AppCompatActivity implements TranslucentListener {
 private Toolbar mToolBar;
 private MyScrollView mScrollView;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_toobar);
  mToolBar = findViewById(R.id.id_toolbar);
  mScrollView = findViewById(R.id.id_scrollView);
  //初始化漸變為0
  mToolBar.setAlpha(0);
  //設置漸變回調
  mScrollView.setTranslucentListener(this);
 }

 @Override
 public void onTranslucent(float alpha) {
  mToolBar.setAlpha(alpha);
 }
}

漸變回調接口

/**
 * @ClassName TranslucentListener
 * @Author rex
 * @Date 2021/1/27 17:38
 */
public interface TranslucentListener {
 /**
  * 透明度的回調監聽
  *
  * @param alpha 0~1 透明度
  */
 public void onTranslucent(float alpha);
}

佈局文件

<RelativeLayout 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">

 <com.rex.rxhttpdemo.MyScrollView
  android:id="@+id/id_scrollView"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:clipChildren="false"
  android:clipToPadding="false"
  >

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

   <Button
    android:id="@+id/button1"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button0" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button1" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button2" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button3" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button4" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button5" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button5" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button5" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button5" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button5" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button5" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button5" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button5" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button" />

   <Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Button" />
  </LinearLayout>
 </com.rex.rxhttpdemo.MyScrollView>

 <androidx.appcompat.widget.Toolbar
  android:id="@+id/id_toolbar"
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:background="@color/colorAccent"
  app:title="title"
  />

</RelativeLayout>

下滑顯示上滑漸變消失

/**
 * @ClassName MyScrollView
 * @Author Rex
 * @Date 2021/1/27 17:38
 */
public class MyScrollView extends ScrollView {
 private TranslucentListener mTranslucentListener;

 public void setTranslucentListener(TranslucentListener translucentListener) {
  this.mTranslucentListener = translucentListener;
 }
 public MyScrollView(Context context) {
  this(context, null);
 }

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

 public MyScrollView(Context context, AttributeSet attrs, int defStyleAttr) {
  this(context, attrs, defStyleAttr, 0);
 }

 public MyScrollView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
  super(context, attrs, defStyleAttr, defStyleRes);
 }

 @Override
 protected void onScrollChanged(int l, int t, int oldl, int oldt) {
  super.onScrollChanged(l, t, oldl, oldt);
  if (mTranslucentListener != null) {
   //ScrollView滑出高度
   int scrollY = getScrollY();
   //屏幕高度
   int screenHeight = getContext().getResources().getDisplayMetrics().heightPixels;
   //有效滑動距離為屏幕2分之一
   // alpha = 滑動高度/（screenHeight/3f）
   if (scrollY <= screenHeight / 2f) {
    Log.d(">>>>>>>>>", "ScrollView劃出高度：" + scrollY);
    Log.d(">>>>>>>>>", "屏幕高度：" + screenHeight);
    Log.d(">>>>>>>>>", "漸變值：" + (1 - scrollY / (screenHeight / 4f)));
    // 漸變的過程 1~0
    mTranslucentListener.onTranslucent(1 - scrollY / (screenHeight /4f));
   }
  }
 }
}

註意: 這裡隻是更改瞭 mTranslucentListener.onTranslucent 裡的 漸變值

Activty 裡 把初始化 mToolBar.setAlpha(0); 去掉

XML

 <com.rex.rxhttpdemo.MyScrollView
  android:id="@+id/id_scrollView"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:clipChildren="false"
  android:clipToPadding="false"
  android:paddingTop="?attr/actionBarSize"
  >
 </com.rex.rxhttpdemo.MyScrollView>

xml 加入 paddingtop .

註意:
android:clipChildren=“false”
android:clipToPadding=”false”
這倆個屬性 如果不加會有留白

到此這篇關於Android 滑動Scrollview標題欄漸變效果(仿京東toolbar)的文章就介紹到這瞭,更多相關Android 滑動Scrollview標題欄漸變內容請搜索WalkonNet以前的文章或繼續瀏覽下面的相關文章希望大傢以後多多支持WalkonNet！

推薦閱讀：