Android自定义锁屏页Demo

package com.example.liujian.lockscreendemo.swipe; import android.app.Activity; import android.content.Context; import android.content.res.TypedArray; import android.util.AttributeSet; import android.view.MotionEvent; import android.view.VelocityTracker; import android.view.View; import android.view.ViewConfiguration; import android.view.ViewGroup; import android.widget.FrameLayout; import android.widget.Scroller; /** * @author xiaanming * @blog http://blog.csdn.net/xiaanming */ public class SwipeUpLayout extends FrameLayout { private static final String TAG = SwipeUpLayout.class.getSimpleName( ); private static final long MAX_VELOCITY_Y = -4000; private VelocityTracker mVelocityTracker; private int mPointerId; private int mMaxVelocity; private boolean needFinish = false; private View mContentView; private int mTouchSlop; private int downX; private int downY; private int tempX; private int tempY; private Scroller mScroller; private int viewWidth; private int viewHeight; private boolean isSilding; private boolean isFinish; private Activity mActivity; private OnSwipeBackListener mListener; public interface OnSwipeBackListener { void onFinish( ); } public void setOnSwipeBackListener( OnSwipeBackListener l ) { mListener = l; } public SwipeUpLayout( Context context, AttributeSet attrs ) { this( context, attrs, 0 ); } public SwipeUpLayout( Context context, AttributeSet attrs, int defStyle ) { super( context, attrs, defStyle ); mTouchSlop = ViewConfiguration.get( context ).getScaledTouchSlop( ); mScroller = new Scroller( context ); mMaxVelocity = ViewConfiguration.get( context ).getMaximumFlingVelocity( ); } public void attachToActivity( Activity activity ) { mActivity = activity; TypedArray a = activity.getTheme( ).obtainStyledAttributes( new int[] { android.R.attr.windowBackground } ); int background = a.getResourceId( 0, 0 ); a.recycle( ); ViewGroup decor = ( ViewGroup ) activity.getWindow( ).getDecorView( ); ViewGroup decorChild = ( ViewGroup ) decor.getChildAt( 0 ); decorChild.setBackgroundResource( background ); decor.removeView( decorChild ); addView( decorChild ); setContentView( decorChild ); decor.addView( this ); } private void setContentView( View decorChild ) { mContentView = ( View ) decorChild.getParent( ); } /** * 事件拦截操作 */ @Override public boolean onInterceptTouchEvent( MotionEvent ev ) { if( isFinish ) { return true; } switch( ev.getAction( ) ) { case MotionEvent.ACTION_DOWN: downY = tempY = ( int ) ev.getRawY( ); downX = ( int ) ev.getRawX( ); break; case MotionEvent.ACTION_MOVE: int moveY = ( int ) ev.getRawY( ); // 满足此条件屏蔽SildingFinishLayout里面子类的touch事件 if( moveY - downY > mTouchSlop && Math.abs( ( int ) ev.getRawX( ) - downX ) < mTouchSlop ) { return true; } break; default: break; } return super.onInterceptTouchEvent( ev ); } @Override public boolean onTouchEvent( MotionEvent event ) { acquireVelocityTracker( event ); switch( event.getAction( ) ) { case MotionEvent.ACTION_DOWN: mPointerId = event.getPointerId( 0 ); break; case MotionEvent.ACTION_MOVE: touchEvenMove( event ); break; case MotionEvent.ACTION_UP: touchEvenUp( ); releaseVelocityTracker( ); break; default: break; } return true; } /** * @param event 向VelocityTracker添加MotionEvent * @see VelocityTracker#obtain() * @see VelocityTracker#addMovement(MotionEvent) */ private void acquireVelocityTracker( final MotionEvent event ) { if( null == mVelocityTracker ) { mVelocityTracker = VelocityTracker.obtain( ); } mVelocityTracker.addMovement( event ); } private void releaseVelocityTracker( ) { if( null != mVelocityTracker ) { mVelocityTracker.clear( ); mVelocityTracker.recycle( ); mVelocityTracker = null; } } /** * 记录当前速度 * * @param velocityX x轴速度 * @param velocityY y轴速度 */ private void recodeInfo( final float velocityX, final float velocityY ) { //向上滑动，去到一定加速度，退出 needFinish = velocityY < MAX_VELOCITY_Y; } /** * 向上滑动 */ private void touchEvenUp( ) { isSilding = false; if( mContentView.getScrollY( ) >= viewHeight / 2 || needFinish ) { isFinish = true; scrollUp( ); } else { scrollOrigin( ); isFinish = false; } } /** * 向上滑动 * * @param event */ private void touchEvenMove( MotionEvent event ) { //求伪瞬时速度 mVelocityTracker.computeCurrentVelocity( 1000, mMaxVelocity ); float velocityX = mVelocityTracker.getXVelocity( mPointerId ); float velocityY = mVelocityTracker.getYVelocity( mPointerId ); recodeInfo( velocityX, velocityY ); int moveY = ( int ) event.getRawY( ); int deltaY = tempY - moveY; tempY = moveY; if( moveY - downY < mTouchSlop && Math.abs( ( int ) event.getRawX( ) - downX ) < mTouchSlop ) { isSilding = true; } if( moveY - downY <= 0 && isSilding ) { mContentView.scrollBy( 0, deltaY ); } } @Override protected void onLayout( boolean changed, int l, int t, int r, int b ) { super.onLayout( changed, l, t, r, b ); if( changed ) { viewWidth = this.getWidth( ); viewHeight = this.getHeight( ); } } /** * 向上滚动出界面 */ private void scrollUp( ) { final int delta = ( viewHeight - mContentView.getScrollY( ) ); mScroller.startScroll( 0, mContentView.getScrollY( ), 0, delta + 1, Math.abs( delta ) ); postInvalidate( ); } /** * 从上滚动到起始位置 */ private void scrollOrigin( ) { int delta = mContentView.getScrollY( ); mScroller.startScroll( 0, mContentView.getScrollY( ), 0, -delta, Math.abs( delta ) ); postInvalidate( ); } @Override public void computeScroll( ) { // 调用startScroll的时候scroller.computeScrollOffset()返回true， if( mScroller.computeScrollOffset( ) ) { mContentView.scrollTo( mScroller.getCurrX( ), mScroller.getCurrY( ) ); postInvalidate( ); if( mScroller.isFinished( ) && isFinish ) { mActivity.finish( ); if( mListener != null ) { mListener.onFinish( ); } } } } public void reset( ) { isFinish = false; mScroller.setFinalX( 0 ); mScroller.setFinalY( 0 ); postInvalidate( ); } }