自定义ViewGroup实现ViewPager的滑动效果
来源:互联网 发布:js中数组和对象的区别 编辑:程序博客网 时间:2024/04/27 07:27
看下他的布局文件:
复制代码
通过判断移动距离和移动方向做出不同的响应。欢迎大家一起讨论,一起学习。
- 复制代码
- <?xml version="1.0" encoding="utf-8"?>
- <RelativeLayout
- android:layout_width="fill_parent"
- android:layout_height="fill_parent"
- xmlns:android="http://schemas.android.com/apk/res/android">
- <com.genius.scroll.MyScrollLayout
- xmlns:android="http://schemas.android.com/apk/res/android"
- android:id="@+id/ScrollLayout"
- android:layout_width="fill_parent"
- android:layout_height="fill_parent">
- <FrameLayout
- android:background="@drawable/guide01"
- android:layout_width="fill_parent"
- android:layout_height="fill_parent">
- </FrameLayout>
- <FrameLayout
- android:background="@drawable/guide02"
- android:layout_width="fill_parent"
- android:layout_height="fill_parent">
- </FrameLayout>
- <FrameLayout
- android:background="@drawable/guide03"
- android:layout_width="fill_parent"
- android:layout_height="fill_parent">
- </FrameLayout>
- <FrameLayout
- android:background="@drawable/guide04"
- android:layout_width="fill_parent"
- android:layout_height="fill_parent">
- </FrameLayout>
- <FrameLayout
- android:background="@drawable/guide05"
- android:layout_width="fill_parent"
- android:layout_height="fill_parent">
- </FrameLayout>
- </com.genius.scroll.MyScrollLayout>
- <LinearLayout
- android:orientation="horizontal"
- android:id="@+id/llayout"
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:layout_marginBottom="24.0dip"
- android:layout_alignParentBottom="true"
- android:layout_centerHorizontal="true">
- <ImageView android:clickable="true"
- android:padding="15.0dip"
- android:layout_gravity="center_vertical"
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:src="@drawable/guide_round" />
- <ImageView android:clickable="true"
- android:padding="15.0dip"
- android:layout_gravity="center_vertical"
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:src="@drawable/guide_round" />
- <ImageView android:clickable="true"
- android:padding="15.0dip"
- android:layout_gravity="center_vertical"
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:src="@drawable/guide_round" />
- <ImageView android:clickable="true"
- android:padding="15.0dip"
- android:layout_gravity="center_vertical"
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:src="@drawable/guide_round" />
- <ImageView android:clickable="true"
- android:padding="15.0dip"
- android:layout_gravity="center_vertical"
- android:layout_width="wrap_content"
- android:layout_height="wrap_content"
- android:src="@drawable/guide_round" />
- </LinearLayout>
- </RelativeLayout>
底部的LinearLayout是放了5个按钮,上面使用到了一个自定义的控件:MyScrollLayout下面再看下这个自定义控件:里面使用frameLayout放了5张图片。 - <?xml version="1.0" encoding="utf-8"?>
- 复制代码
- public class MyScrollLayout extends ViewGroup{
-
- private static final String TAG = "ScrollLayout";
- private VelocityTracker mVelocityTracker; // 用于判断甩动手势
- private static final int SNAP_VELOCITY = 600;
- private Scroller mScroller; // 滑动控制器
- private int mCurScreen;
- private int mDefaultScreen = 0;
- private float mLastMotionX;
-
- private OnViewChangeListener mOnViewChangeListener;
- public MyScrollLayout(Context context) {
- super(context);
- init(context);
- }
- public MyScrollLayout(Context context, AttributeSet attrs) {
- super(context, attrs);
- init(context);
- }
- public MyScrollLayout(Context context, AttributeSet attrs, int defStyle) {
- super(context, attrs, defStyle);
- init(context);
- }
- private void init(Context context)
- {
- mCurScreen = mDefaultScreen;
- mScroller = new Scroller(context);
- }
-
- @Override
- protected void onLayout(boolean changed, int l, int t, int r, int b) {
- // TODO Auto-generated method stub
- if (changed) {
- int childLeft = 0;
- final int childCount = getChildCount();
- for (int i=0; i<childCount; i++) {
- final View childView = getChildAt(i);
- if (childView.getVisibility() != View.GONE) {
- final int childWidth = childView.getMeasuredWidth();
- childView.layout(childLeft, 0,
- childLeft+childWidth, childView.getMeasuredHeight());
- childLeft += childWidth;
- }
- }
- }
- }
-
- @Override
- protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
- // TODO Auto-generated method stub
- super.onMeasure(widthMeasureSpec, heightMeasureSpec);
- final int width = MeasureSpec.getSize(widthMeasureSpec);
- final int widthMode = MeasureSpec.getMode(widthMeasureSpec);
- final int count = getChildCount();
- for (int i = 0; i < count; i++) {
- getChildAt(i).measure(widthMeasureSpec, heightMeasureSpec);
- }
- scrollTo(mCurScreen * width, 0);
- }
-
- public void snapToDestination() {
- final int screenWidth = getWidth();
- final int destScreen = (getScrollX()+ screenWidth/2)/screenWidth;
- snapToScreen(destScreen);
- }
-
- public void snapToScreen(int whichScreen) {
- // get the valid layout page
- whichScreen = Math.max(0, Math.min(whichScreen, getChildCount()-1));
- if (getScrollX() != (whichScreen*getWidth())) {
- final int delta = whichScreen*getWidth()-getScrollX();
- mScroller.startScroll(getScrollX(), 0,
- delta, 0, Math.abs(delta)*2);
- mCurScreen = whichScreen;
- invalidate(); // Redraw the layout
- if (mOnViewChangeListener != null)
- {
- mOnViewChangeListener.OnViewChange(mCurScreen);
- }
- }
- }
-
- @Override
- public void computeScroll() {
- // TODO Auto-generated method stub
- if (mScroller.computeScrollOffset()) {
- scrollTo(mScroller.getCurrX(), mScroller.getCurrY());
- postInvalidate();
- }
- }
-
- @Override
- public boolean onTouchEvent(MotionEvent event) {
- // TODO Auto-generated method stub
- final int action = event.getAction();
- final float x = event.getX();
- final float y = event.getY();
- switch (action) {
- case MotionEvent.ACTION_DOWN:
- Log.i("", "onTouchEvent ACTION_DOWN");
- if (mVelocityTracker == null) {
- mVelocityTracker = VelocityTracker.obtain();
- mVelocityTracker.addMovement(event);
- }
- if (!mScroller.isFinished()){
- mScroller.abortAnimation();
- }
- mLastMotionX = x;
- break;
- case MotionEvent.ACTION_MOVE:
- int deltaX = (int)(mLastMotionX - x);
- if (IsCanMove(deltaX)){
- if (mVelocityTracker != null){
- mVelocityTracker.addMovement(event);
- }
- mLastMotionX = x;
- scrollBy(deltaX, 0);
- }
- break;
- case MotionEvent.ACTION_UP:
- int velocityX = 0;
- if (mVelocityTracker != null){
- mVelocityTracker.addMovement(event);
- mVelocityTracker.computeCurrentVelocity(1000);
- velocityX = (int) mVelocityTracker.getXVelocity();
- }
- if (velocityX > SNAP_VELOCITY && mCurScreen > 0) {
- Log.e(TAG, "snap left");
- snapToScreen(mCurScreen - 1);
- } else if (velocityX < -SNAP_VELOCITY
- && mCurScreen < getChildCount() - 1) {
- Log.e(TAG, "snap right");
- snapToScreen(mCurScreen + 1);
- } else {
- snapToDestination();
- }
- if (mVelocityTracker != null) {
- mVelocityTracker.recycle();
- mVelocityTracker = null;
- }
- break;
- }
- return true;
- }
-
- private boolean IsCanMove(int deltaX)
- {
- if (getScrollX() <= 0 && deltaX < 0 ){
- return false;
- }
- if (getScrollX() >= (getChildCount() - 1) * getWidth() && deltaX > 0){
- return false;
- }
- return true;
- }
-
- public void SetOnViewChangeListener(OnViewChangeListener listener)
- {
- mOnViewChangeListener = listener;
- }
- }
首先注意,他继承了ViewGroup类,在这里面主要重写了onMeasure()、onTouchEvent()等方法,在这里使用了一个自定义的接口private OnViewChangeListener mOnViewChangeListener。看下它的定义: - public class MyScrollLayout extends ViewGroup{
- 复制代码
- public interface OnViewChangeListener {
- public void OnViewChange(int view);
- }
这个接口里之定义了一个回调方法:OnViewChange()这个方法的具体实现,是在主Activity中: - public interface OnViewChangeListener {
- 复制代码
- public class SwitchViewDemoActivity extends Activity implements OnViewChangeListener, OnClickListener{
- /** Called when the activity is first created. */
-
- private MyScrollLayout mScrollLayout;
- private ImageView[] mImageViews;
- private int mViewCount;
- private int mCurSel;
-
- @Override
- public void onCreate(Bundle savedInstanceState) {
- super.onCreate(savedInstanceState);
- setContentView(R.layout.main);
- init();
- }
-
- private void init()
- {
- mScrollLayout = (MyScrollLayout) findViewById(R.id.ScrollLayout);
- LinearLayout linearLayout = (LinearLayout) findViewById(R.id.llayout);
- mViewCount = mScrollLayout.getChildCount();
- mImageViews = new ImageView[mViewCount];
- for(int i = 0; i < mViewCount; i++) {
- mImageViews = (ImageView) linearLayout.getChildAt(i);
- mImageViews.setEnabled(true);
- mImageViews.setOnClickListener(this);
- mImageViews.setTag(i);
- }
- mCurSel = 0;
- mImageViews[mCurSel].setEnabled(false);
- mScrollLayout.SetOnViewChangeListener(this);
- }
-
- private void setCurPoint(int index)
- {
- if (index < 0 || index > mViewCount - 1 || mCurSel == index) {
- return ;
- }
- mImageViews[mCurSel].setEnabled(true);
- mImageViews[index].setEnabled(false);
- mCurSel = index;
- }
-
- @Override
- public void OnViewChange(int view) {
- // TODO Auto-generated method stub
- setCurPoint(view);
- }
-
- @Override
- public void onClick(View v) {
- // TODO Auto-generated method stub
- int pos = (Integer)(v.getTag());
- setCurPoint(pos);
- mScrollLayout.snapToScreen(pos);
- }
- }
这个OnViewChange()方法,主要调用了setCurPoint()方法,就是完成界面的跳转。在MyScrollLayout中的snapToScreen()方法中就是典型的回调方法: - public class SwitchViewDemoActivity extends Activity implements OnViewChangeListener, OnClickListener{
- 复制代码
- public void snapToScreen(int whichScreen) {
- // get the valid layout page
- whichScreen = Math.max(0, Math.min(whichScreen, getChildCount()-1));
- if (getScrollX() != (whichScreen*getWidth())) {
- final int delta = whichScreen*getWidth()-getScrollX();
- mScroller.startScroll(getScrollX(), 0,
- delta, 0, Math.abs(delta)*2);
- mCurScreen = whichScreen;
- invalidate(); // Redraw the layout
- if (mOnViewChangeListener != null)
- {
- mOnViewChangeListener.OnViewChange(mCurScreen);
- }
- }
- }
- public void snapToScreen(int whichScreen) {
- mOnViewChangeListener.OnViewChange(mCurScreen);
这句代码就是典型的回调。
在MyScrollLayout的onTouchEvent()的方法里面是对触屏事件做出的响应:
- final int action = event.getAction();
- final float x = event.getX();
- final float y = event.getY();
- switch (action) {
- case MotionEvent.ACTION_DOWN:
- Log.i("", "onTouchEvent ACTION_DOWN");
- if (mVelocityTracker == null) {
- mVelocityTracker = VelocityTracker.obtain();
- mVelocityTracker.addMovement(event);
- }
- if (!mScroller.isFinished()){
- mScroller.abortAnimation();
- }
- mLastMotionX = x;
- break;
- case MotionEvent.ACTION_MOVE:
- int deltaX = (int)(mLastMotionX - x);
- if (IsCanMove(deltaX)){
- if (mVelocityTracker != null){
- mVelocityTracker.addMovement(event);
- }
- mLastMotionX = x;
- scrollBy(deltaX, 0);
- }
- break;
- case MotionEvent.ACTION_UP:
- int velocityX = 0;
- if (mVelocityTracker != null){
- mVelocityTracker.addMovement(event);
- mVelocityTracker.computeCurrentVelocity(1000);
- velocityX = (int) mVelocityTracker.getXVelocity();
- }
- if (velocityX > SNAP_VELOCITY && mCurScreen > 0) {
- Log.e(TAG, "snap left");
- snapToScreen(mCurScreen - 1);
- } else if (velocityX < -SNAP_VELOCITY
- && mCurScreen < getChildCount() - 1) {
- Log.e(TAG, "snap right");
- snapToScreen(mCurScreen + 1);
- } else {
- snapToDestination();
- }
- if (mVelocityTracker != null) {
- mVelocityTracker.recycle();
- mVelocityTracker = null;
- }
- break;
- }
通过判断移动距离和移动方向做出不同的响应。欢迎大家一起讨论,一起学习。
0 0
- 自定义ViewGroup实现ViewPager的滑动效果
- 自定义ViewGroup实现类似ViewPager的滑动效果
- 自定义ViewGroup实现纵向滑动切换的ViewPager
- 自定义ViewGroup实现弹性滑动效果
- 自定义类似ViewPager的效果的ViewGroup
- Android 使用ViewGroup实现ViewPager的效果
- 【安卓自定义控件】自定义ViewGroup实现透明背景的ViewPager效果
- 自定义ViewGroup实现多个单页面上下滑动效果
- 自定义ViewGroup实现多个单页面上下滑动效果
- android 自定义Viewpager 实现静止滑动,并去掉默认的滑动效果
- 使用自定义RadioButton和ViewPager实现TabHost效果和带滑动的页卡效果。
- ViewPager+Fragment 实现滑动页面的效果
- 实现viewpager的无限滑动效果
- 实现ViewPager的不同滑动效果
- 自定义ViewGroup实现水平滑动
- 自定义RecyclerView实现垂直滑动的ViewPager
- android-使用ViewGroup实现左右滑动切换界面的效果
- 实现ViewPager底部条跟着ViewPager滑动的效果
- Android应用签名打包(一)
- 使用Gradle发布项目到JCenter仓库
- 使用python实现二叉搜索树
- Spark通过mapPartitions方式加载Json文件,提高文件加载速度
- uploadify 发送多余请求的问题
- 自定义ViewGroup实现ViewPager的滑动效果
- Kettle REST Client生成经纬度
- MATLAB把pgm格式转换为jpg
- AndroidStudio操作笔记--如何加载外部aar包
- 求最大值
- iOS 图片加载 圆形进度条
- app引导页
- 自定义数字键盘 HJNumKeyBoard
- netstat命令用法(转载)