启动引导界面实现(类似手机主界面切换应用屏幕)

我们手机安装很多应用时，分屏摆放，不同屏的应用切换时的效果我们使用得多，如何实现呢?转载自:

高仿launcher和墨迹左右拖动效果

(1)主界面代码SwitchViewDemoActivity.java:

package com.example.switchview;

import android.app.Activity;
import android.os.Bundle;
import android.view.Gravity;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.LinearLayout.LayoutParams;

public class SwitchViewDemoActivity extends Activity implements
		OnViewChangeListener, OnClickListener {

	private MyScrollLayout mScrollLayout;
	private ImageView[] mImageViews;
	private int mViewCount;
	private int mCurSel;

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		init();

	}

	private void init() {
		mScrollLayout = (MyScrollLayout) findViewById(R.id.ScrollLayout);
		LinearLayout linearLayout = (LinearLayout) findViewById(R.id.llayout);
		
		
		//如果不想写死在布局文件里也可以动态添加，这里动态添加一个作为示例
		// 动态添加一个layout控件
		LinearLayout layout = new LinearLayout(this);
		layout.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.FILL_PARENT));
		layout.setBackgroundResource(R.drawable.mm_1);
		mScrollLayout.addView(layout);
		
		// 动态添加一个imageView控件
		ImageView imageView = new ImageView(this);
		LayoutParams lp = new LayoutParams(LayoutParams.WRAP_CONTENT,
				LayoutParams.WRAP_CONTENT);
		lp.gravity = Gravity.CENTER;
		imageView.setLayoutParams(lp);
		imageView.setPadding(15, 15, 15, 15);
		imageView.setImageResource(R.drawable.white_dot);
		linearLayout.addView(imageView);
		

		
		
		mViewCount = mScrollLayout.getChildCount();
		mImageViews = new ImageView[mViewCount];
		for (int i = 0; i < mViewCount; i++) {
			mImageViews[i] = (ImageView) linearLayout.getChildAt(i);
			mImageViews[i].setEnabled(true);
			mImageViews[i].setOnClickListener(this);
			mImageViews[i].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].setImageResource(R.drawable.white_dot);
		mImageViews[index].setImageResource(R.drawable.green_dot);
				
		mImageViews[mCurSel].setEnabled(true);
		mImageViews[index].setEnabled(false);
		mCurSel = index;
	}

	@Override
	public void OnViewChange(int view) {
		setCurPoint(view);
	}

	@Override
	public void onClick(View v) {
		int pos = (Integer) (v.getTag());
		setCurPoint(pos);
		mScrollLayout.snapToScreen(pos);
	}
}

(2) 主滑动自定义控件MyScrollLayout.java:

package com.example.switchview;

import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.VelocityTracker;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Scroller;

/**
 * 一组图片滑动主控件
 * 
 * @author chenwenbiao
 * @date 2014-6-7 下午3:55:12
 * @version V1.0
 */
public class MyScrollLayout extends ViewGroup {

	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 int mTouchSlop;

	private OnViewChangeListener mOnViewChangeListener;

	public MyScrollLayout(Context context) {
		super(context);
		// TODO Auto-generated constructor stub
		init(context);
	}

	public MyScrollLayout(Context context, AttributeSet attrs) {
		super(context, attrs);
		// TODO Auto-generated constructor stub
		init(context);
	}

	public MyScrollLayout(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
		// TODO Auto-generated constructor stub
		init(context);
	}

	private void init(Context context) {
		mCurScreen = mDefaultScreen;
		// mTouchSlop =
		// ViewConfiguration.get(getContext()).getScaledTouchSlop();
		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) {
				// Fling enough to move left
				snapToScreen(mCurScreen - 1);
			} else if (velocityX < -SNAP_VELOCITY
					&& mCurScreen < getChildCount() - 1) {
				// Fling enough to move right
				snapToScreen(mCurScreen + 1);
			} else {
				snapToDestination();
			}

			if (mVelocityTracker != null) {
				mVelocityTracker.recycle();
				mVelocityTracker = null;
			}
			// mTouchState = TOUCH_STATE_REST;
			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;
	}
}

（3）接口OnViewChangeListener:

package com.example.switchview;

public interface OnViewChangeListener {
	public void OnViewChange(int view);
}

（4）布局文件activity_main.xml:

<?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.example.switchview.MyScrollLayout
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/ScrollLayout"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" >

        <LinearLayout
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:background="@drawable/mm_1" >
        </LinearLayout>

        <LinearLayout
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:background="@drawable/mm_2" >
        </LinearLayout>

        <LinearLayout
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:background="@drawable/mm_3" >
        </LinearLayout>

        <LinearLayout
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:background="@drawable/mm_4" >
        </LinearLayout>

        <LinearLayout
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:background="@drawable/mm_5" >
        </LinearLayout>
    </com.example.switchview.MyScrollLayout>

    <LinearLayout
        android:id="@+id/llayout"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:layout_marginBottom="24.0dip"
        android:orientation="horizontal" >

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical"
            android:clickable="true"
            android:padding="15.0dip"
            android:src="@drawable/green_dot" />

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical"
            android:clickable="true"
            android:padding="15.0dip"
            android:src="@drawable/white_dot" />

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical"
            android:clickable="true"
            android:padding="15.0dip"
            android:src="@drawable/white_dot" />

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical"
            android:clickable="true"
            android:padding="15.0dip"
            android:src="@drawable/white_dot" />

        <ImageView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical"
            android:clickable="true"
            android:padding="15.0dip"
            android:src="@drawable/white_dot" />
    </LinearLayout>

</RelativeLayout>

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效果图:

切换的都是图片，这里可能会使用到就是点，也上传了.