android 上下滑屏

最近比较闲，想起墨迹左右滑屏的效果该如何实现，如是在网上搜索资料，都没看到理想的效果，于是参照别人的例子自己加以修改，最终效果还行。左右滑屏是通过ViewGroup结合手势划屏来实现，代码如下：

package com.scroll.test;import com.scroll.test.R;import android.app.Activity;import android.os.Bundle;import android.util.Log;import android.view.View;import android.view.View.OnClickListener;import android.view.View.OnFocusChangeListener;import android.widget.Button;public class ScrollLayoutTest extends Activity {	private ScrollLayout sl;	private Button btn1;	private PageControlView pageControlView;	@Override	public void onCreate(Bundle savedInstanceState) {		super.onCreate(savedInstanceState);		setContentView(R.layout.main);		sl = (ScrollLayout) findViewById(R.id.ScrollLayoutTest);		pageControlView = (PageControlView) findViewById(R.id.pageControl);		btn1 = (Button) findViewById(R.id.btn1);		btn1.setOnClickListener(new OnClickListener() {			@Override			public void onClick(View v) {				sl.snapToScreen(1);			}		});		sl.setOnFocusChangeListener(new OnFocusChangeListener() {			@Override			public void onFocusChange(View v, boolean hasFocus) {				int i = v.getVisibility();				Log.v("=sl.i=", i + "=");			}		});		Log.v("=sl.getCurScreen()=", sl.getCurScreen() + "=");		pageControlView.bindScrollLayout(sl);	}}

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package com.scroll.test;import android.content.Context;import android.graphics.Canvas;import android.util.AttributeSet;import android.util.Log;import android.view.MotionEvent;import android.view.VelocityTracker;import android.view.View;import android.view.ViewConfiguration;import android.view.ViewGroup;import android.widget.Scroller;/** * 仿Launcher中的WorkSapce，可以左右滑动切换屏幕的类 *  *  *  */public class ScrollLayout extends ViewGroup {	private static final String TAG = "ScrollLayout";	private Scroller mScroller;	private VelocityTracker mVelocityTracker;	private int mCurScreen;	private int mDefaultScreen = 0;	private static final int TOUCH_STATE_REST = 0;	private static final int TOUCH_STATE_SCROLLING = 1;	private static final int SNAP_VELOCITY = 600;	private int mTouchState = TOUCH_STATE_REST;	private int mTouchSlop;	private float mLastMotionX;	private float mLastMotionY;	public ScrollLayout(Context context, AttributeSet attrs) {		this(context, attrs, 0);		// TODO Auto-generated constructor stub	}	public ScrollLayout(Context context, AttributeSet attrs, int defStyle) {		super(context, attrs, defStyle);		// TODO Auto-generated constructor stub		mScroller = new Scroller(context);		mCurScreen = mDefaultScreen;		mTouchSlop = ViewConfiguration.get(getContext()).getScaledTouchSlop();	}	@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) {		Log.e(TAG, "onMeasure");		super.onMeasure(widthMeasureSpec, heightMeasureSpec);		final int width = MeasureSpec.getSize(widthMeasureSpec);		final int widthMode = MeasureSpec.getMode(widthMeasureSpec);		if (widthMode != MeasureSpec.EXACTLY) {			throw new IllegalStateException(					"ScrollLayout only canmCurScreen run at EXACTLY mode!");		}		final int heightMode = MeasureSpec.getMode(heightMeasureSpec);		if (heightMode != MeasureSpec.EXACTLY) {			throw new IllegalStateException(					"ScrollLayout only can run at EXACTLY mode!");		}		// The children are given the same width and height as the scrollLayout		final int count = getChildCount();		for (int i = 0; i < count; i++) {			getChildAt(i).measure(widthMeasureSpec, heightMeasureSpec);		}		// Log.e(TAG, "moving to screen "+mCurScreen);		scrollTo(mCurScreen * width, 0);	}	/**	 * According to the position of current layout scroll to the destination	 * page.	 */	public void snapToDestination() {		final int screenWidth = getWidth();		final int destScreen = (getScrollX() + screenWidth / 2) / screenWidth;		snapToScreen(destScreen);		// 设置循环滑屏方法一：		// 设置使循环（5表示总共有多少屏）	/*	if (destScreen == 0) {			setToScreen(5);		} else if (destScreen == 5) {			setToScreen(0);		} else {			// 设置不循环			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;			onScreenChangeListener.onScreenChange(mCurScreen);			invalidate(); // Redraw the layout		}	}	public void setToScreen(int whichScreen) {		whichScreen = Math.max(0, Math.min(whichScreen, getChildCount() - 1));		mCurScreen = whichScreen;		scrollTo(whichScreen * getWidth(), 0);		//设置循环滑屏方法二：		//onScreenChangeListener.onScreenChange(mCurScreen);	}	public int getCurScreen() {		return 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		if (mVelocityTracker == null) {			mVelocityTracker = VelocityTracker.obtain();		}		mVelocityTracker.addMovement(event);		final int action = event.getAction();		final float x = event.getX();		final float y = event.getY();		switch (action) {		case MotionEvent.ACTION_DOWN:			Log.e(TAG, "event down!");			if (!mScroller.isFinished()) {				mScroller.abortAnimation();			}			mLastMotionX = x;			break;		case MotionEvent.ACTION_MOVE:			int deltaX = (int) (mLastMotionX - x);			mLastMotionX = x;			scrollBy(deltaX, 0);			break;		case MotionEvent.ACTION_UP:			Log.e(TAG, "event : up");			// if (mTouchState == TOUCH_STATE_SCROLLING) {			final VelocityTracker velocityTracker = mVelocityTracker;			velocityTracker.computeCurrentVelocity(1000);			int velocityX = (int) velocityTracker.getXVelocity();			Log.e(TAG, "velocityX:" + velocityX);			if (velocityX > SNAP_VELOCITY && mCurScreen > 0) {				// Fling enough to move left				// onScreenChangeListener.onScreenChange(mCurScreen - 1);				Log.e(TAG, "snap left");				snapToScreen(mCurScreen - 1);			} else if (velocityX < -SNAP_VELOCITY					&& mCurScreen < getChildCount() - 1) {				// Fling enough to move right				Log.e(TAG, "snap right");				// onScreenChangeListener.onScreenChange(mCurScreen + 1);				snapToScreen(mCurScreen + 1);			} else {				snapToDestination();			}			if (mVelocityTracker != null) {				mVelocityTracker.recycle();				mVelocityTracker = null;			}			// }			mTouchState = TOUCH_STATE_REST;			break;		case MotionEvent.ACTION_CANCEL:			mTouchState = TOUCH_STATE_REST;			break;		}		return true;	}	@Override	public boolean onInterceptTouchEvent(MotionEvent ev) {		// TODO Auto-generated method stub		Log.e(TAG, "onInterceptTouchEvent-slop:" + mTouchSlop);		final int action = ev.getAction();		if ((action == MotionEvent.ACTION_MOVE)				&& (mTouchState != TOUCH_STATE_REST)) {			return true;		}		final float x = ev.getX();		final float y = ev.getY();		switch (action) {		case MotionEvent.ACTION_MOVE:			final int xDiff = (int) Math.abs(mLastMotionX - x);			if (xDiff > mTouchSlop) {				mTouchState = TOUCH_STATE_SCROLLING;			}			break;		case MotionEvent.ACTION_DOWN:			mLastMotionX = x;			mLastMotionY = y;			mTouchState = mScroller.isFinished() ? TOUCH_STATE_REST					: TOUCH_STATE_SCROLLING;			break;		case MotionEvent.ACTION_CANCEL:		case MotionEvent.ACTION_UP:			mTouchState = TOUCH_STATE_REST;			break;		}		return mTouchState != TOUCH_STATE_REST;	}	// 监听页面变动	public interface OnScreenChangeListener {		void onScreenChange(int currentIndex);	}	private OnScreenChangeListener onScreenChangeListener;	public void setOnScreenChangeListener(			OnScreenChangeListener onScreenChangeListener) {		this.onScreenChangeListener = onScreenChangeListener;	}}

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package com.scroll.test;import com.scroll.test.ScrollLayout.OnScreenChangeListener;import com.scroll.test.R;import android.R.integer;import android.content.Context;import android.util.AttributeSet;import android.util.Log;import android.widget.FrameLayout;import android.widget.ImageView;import android.widget.LinearLayout;public class PageControlView extends LinearLayout {	private Context context;	private int count;	public PageControlView(Context context) {		super(context);		this.context = context;	}	public PageControlView(Context context, AttributeSet attrs) {		super(context, attrs);		this.context = context;	}	public void bindScrollLayout(ScrollLayout scrollLayout) {		this.count = scrollLayout.getChildCount();		Log.v("=count==", count + "=");		// 初始化第一屏		generatePageControl(0);		scrollLayout.setOnScreenChangeListener(new OnScreenChangeListener() {			@Override			public void onScreenChange(int currentIndex) {				generatePageControl(currentIndex);			}		});	}	private void generatePageControl(int currentIndex) {		this.removeAllViews();		for (int i = 0; i < this.count; i++) {			Log.v("=i==", i + "=");			ImageView imageView = new ImageView(context);			if (i == currentIndex) {				imageView.setImageResource(R.drawable.page_indicator_focused);			} else {				imageView.setImageResource(R.drawable.page_indicator);			}			this.addView(imageView);		}	}}

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<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"	android:layout_width="fill_parent" android:layout_height="fill_parent">	<com.scroll.test.ScrollLayout		xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/ScrollLayoutTest"		android:layout_width="fill_parent" android:layout_height="fill_parent">		<LinearLayout android:background="#FF00"			android:layout_width="fill_parent" android:layout_height="fill_parent"></LinearLayout>		<FrameLayout android:background="#F0F0"			android:layout_width="fill_parent" android:layout_height="fill_parent"></FrameLayout>		<FrameLayout android:background="#F00F"			android:layout_width="fill_parent" android:layout_height="fill_parent">		</FrameLayout>		<LinearLayout android:background="#FF00"			android:layout_width="fill_parent" android:layout_height="fill_parent">			<Button android:layout_width="wrap_content"				android:layout_height="wrap_content" android:text="Button1"				android:id="@+id/btn1" />		</LinearLayout>		<LinearLayout android:layout_width="wrap_content"			android:layout_height="wrap_content">			<Button android:layout_width="wrap_content"				android:layout_height="wrap_content" android:text="Button2" />		</LinearLayout>	</com.scroll.test.ScrollLayout>	<com.scroll.test.PageControlView		android:id="@+id/pageControl" android:layout_width="wrap_content"		android:layout_height="wrap_content" android:layout_centerHorizontal="true"		android:layout_alignParentBottom="true">	</com.scroll.test.PageControlView></RelativeLayout>

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?? 附近是具体的源码。

1 楼 轻指飞扬 2012-05-31  

很强啊 ，没用android-support-v4就实现了这个效果