本文讲述了Android TV开发:实现3D仿Gallery效果的实例代码。分享给大家供大家参考,具体如下:
1.实现效果:
滚动翻页+ 页面点击+页码指示器+焦点控制
2.实现这个效果之前必须要了解
Android高级图片滚动控件实现3D版图片轮播器这篇文章,我是基于他的代码进行修改的,主要为了移植到电视上做了按键事件和焦点控制。
3.具体代码:
public class Image3DSwitchView extends LinearLayout { private int currentPage =0;//定义当前第几页 /** * 图片左右两边的空白间距 */ public static final int IMAGE_PADDING = 5; private static final int TOUCH_STATE_REST = 0; private static final int TOUCH_STATE_SCROLLING = 1; /** * 滚动到下一张图片的速度 */ private static final int SNAP_VELOCITY = 600; /** * 表示滚动到下一张图片这个动作 */ private static final int SCROLL_NEXT = 0; /** * 表示滚动到上一张图片这个动作 */ private static final int SCROLL_PREVIOUS = 1; /** * 表示滚动回原图片这个动作 */ private static final int SCROLL_BACK = 2; private static Handler handler = new Handler(); /** * 控件宽度 */ public static int mWidth; private VelocityTracker mVelocityTracker;//主要用跟踪触摸屏事件(flinging事件和其他gestures手势事件)的速率 private Scroller mScroller; /** * 图片滚动监听器,当图片发生滚动时回调这个接口 */ private OnImageSwitchListener mListener; /** * 记录当前的触摸状态 */ private int mTouchState = TOUCH_STATE_REST; /** * 记录被判定为滚动运动的最小滚动值 */ private int mTouchSlop; /** * 记录控件高度 */ private int mHeight; /** * 记录每张图片的宽度 */ private int mImageWidth; /** * 记录图片的总数量 */ private int mCount; /** * 记录当前显示图片的坐标 */ private int mCurrentImage; /** * 记录上次触摸的横坐标值 */ private float mLastMotionX; /** * 是否强制重新布局 */ private boolean forceToRelayout; private int[] mItems; public Image3DSwitchView(Context context, AttributeSet attrs) { super(context, attrs); mTouchSlop = ViewConfiguration.get(getContext()).getScaledTouchSlop(); mScroller = new Scroller(context); //设置可以获得焦点 setFocusable(true); } @Override protected void onLayout(boolean changed, int l, int t, int r, int b) { if (changed || forceToRelayout) { mCount = getChildCount(); // 图片数量必须大于5,不然无法正常显示 if (mCount < 5) { return; } mWidth = getMeasuredWidth(); mHeight = getMeasuredHeight(); // 每张图片的宽度设定为控件宽度的百分之六十 mImageWidth = (int) (mWidth * 0.6); if (mCurrentImage >= 0 && mCurrentImage < mCount) { mScroller.abortAnimation(); setScrollX(0); int left = -mImageWidth * 2 + (mWidth - mImageWidth) / 2; // 分别获取每个位置上应该显示的图片下标 int[] items = {getIndexForItem(1), getIndexForItem(2), getIndexForItem(3), getIndexForItem(4), getIndexForItem(5)}; mItems = items; // 通过循环为每张图片设定位置 for (int i = 0; i < items.length; i++) { Image3DView childView = (Image3DView) getChildAt(items[i]); childView.layout(left + IMAGE_PADDING, 0, left + mImageWidth - IMAGE_PADDING, mHeight); childView.initImageViewBitmap(); left = left + mImageWidth; } refreshImageShowing(); } forceToRelayout = false; } } public interface OnFocusListener{ void onFocus(); void setValue(String value); } private OnFocusListener onFocusListener; public void setonFocusListener(OnFocusListener onFocusListener){ this.onFocusListener = onFocusListener; } @Override public boolean dispatchKeyEvent(KeyEvent event) { if (event.getAction() == KeyEvent.ACTION_DOWN){ switch (event.getKeyCode()){ //按下键 响应回调 case KeyEvent.KEYCODE_DPAD_DOWN: if (onFocusListener != null){onFocusListener.onFocus();} break; //按确定键 case KeyEvent.KEYCODE_DPAD_CENTER: Toast.makeText(getContext(),"点击了图片"+(currentPage%7+1),Toast.LENGTH_SHORT).show(); break; //右键 case KeyEvent.KEYCODE_DPAD_RIGHT: scrollToNext(); if (onFocusListener !=null){ onFocusListener.setValue((currentPage%7+1)+""); } break; //左键 case KeyEvent.KEYCODE_DPAD_LEFT: scrollToPrevious(); if (onFocusListener !=null){ onFocusListener.setValue((currentPage%7+1)+""); } break; } } return true; } @Override public boolean onTouchEvent(MotionEvent event) { if (mScroller.isFinished()) { if (mVelocityTracker == null) { mVelocityTracker = VelocityTracker.obtain(); } mVelocityTracker.addMovement(event); int action = event.getAction(); float x = event.getX(); switch (action) { case MotionEvent.ACTION_DOWN: // 记录按下时的横坐标 mLastMotionX = x; break; case MotionEvent.ACTION_MOVE: int disX = (int) (mLastMotionX - x); mLastMotionX = x; scrollBy(disX, 0); // 当发生移动时刷新图片的显示状态 refreshImageShowing(); break; case MotionEvent.ACTION_UP: mVelocityTracker.computeCurrentVelocity(1000); int velocityX = (int) mVelocityTracker.getXVelocity(); if (shouldScrollToNext(velocityX)) { // 滚动到下一张图 scrollToNext(); } else if (shouldScrollToPrevious(velocityX)) { // 滚动到上一张图 scrollToPrevious(); } else { // 滚动回当前图片 scrollBack(); } if (mVelocityTracker != null) { mVelocityTracker.recycle(); mVelocityTracker = null; } break; } } return true; } /** * 根据当前的触摸状态来决定是否屏蔽子控件的交互能力。 */ @Override public boolean onInterceptTouchEvent(MotionEvent ev) { int action = ev.getAction(); if ((action == MotionEvent.ACTION_MOVE) && (mTouchState != TOUCH_STATE_REST)) { return true; } float x = ev.getX(); switch (action) { case MotionEvent.ACTION_DOWN: mLastMotionX = x; mTouchState = TOUCH_STATE_REST; break; case MotionEvent.ACTION_MOVE: int xDiff = (int) Math.abs(mLastMotionX - x); if (xDiff > mTouchSlop) { mTouchState = TOUCH_STATE_SCROLLING; } break; case MotionEvent.ACTION_UP: default: mTouchState = TOUCH_STATE_REST; break; } return mTouchState != TOUCH_STATE_REST; } @Override public void computeScroll() { if (mScroller.computeScrollOffset()) { scrollTo(mScroller.getCurrX(), mScroller.getCurrY()); refreshImageShowing(); postInvalidate(); } } /** * 设置图片滚动的监听器,每当有图片滚动时会回调此接口。 * * @param listener 图片滚动监听器 */ public void setOnImageSwitchListener(OnImageSwitchListener listener) { mListener = listener; } /** * 设置当前显示图片的下标,注意如果该值小于零或大于等于图片的总数量,图片则无法正常显示。 * * @param currentImage 图片的下标 */ public void setCurrentImage(int currentImage) { mCurrentImage = currentImage; requestLayout(); } /** * 滚动到下一张图片。 */ public void scrollToNext() { if (mScroller.isFinished()) { currentPage++; int disX = mImageWidth - getScrollX(); checkImageSwitchBorder(SCROLL_NEXT); if (mListener != null) { mListener.onImageSwitch(mCurrentImage); } beginScroll(getScrollX(), 0, disX, 0, SCROLL_NEXT); } } /** * 滚动到上一张图片。 */ public void scrollToPrevious() { if (mScroller.isFinished()) { if (currentPage ==0){ currentPage = 7; }else currentPage--; int disX = -mImageWidth - getScrollX(); checkImageSwitchBorder(SCROLL_PREVIOUS); if (mListener != null) { mListener.onImageSwitch(mCurrentImage); } beginScroll(getScrollX(), 0, disX, 0, SCROLL_PREVIOUS); } } /** * 滚动回原图片。 */ public void scrollBack() { if (mScroller.isFinished()) { beginScroll(getScrollX(), 0, -getScrollX(), 0, SCROLL_BACK); } } /** * 回收所有图片对象,释放内存。 */ public void clear() { for (int i = 0; i < mCount; i++) { Image3DView childView = (Image3DView) getChildAt(i); childView.recycleBitmap(); } } /** * 让控件中的所有图片开始滚动。 */ private void beginScroll(int startX, int startY, int dx, int dy, final int action) { int duration = (int) (700f / mImageWidth * Math.abs(dx)); mScroller.startScroll(startX, startY, dx, dy, duration); invalidate(); handler.postDelayed(new Runnable() { @Override public void run() { if (action == SCROLL_NEXT || action == SCROLL_PREVIOUS) { forceToRelayout = true; requestLayout(); } } }, duration); } /** * 根据当前图片的下标和传入的item参数,来判断item位置上应该显示哪张图片。 * * @param item 取值范围是1-5 * @return 对应item位置上应该显示哪张图片。 */ private int getIndexForItem(int item) { int index = -1; index = mCurrentImage + item - 3; while (index < 0) { index = index + mCount; } while (index > mCount - 1) { index = index - mCount; } return index; } /** * 刷新所有图片的显示状态,包括当前的旋转角度。 */ private void refreshImageShowing() { for (int i = 0; i < mItems.length; i++) { Image3DView childView = (Image3DView) getChildAt(mItems[i]); childView.setRotateData(i, getScrollX()); childView.invalidate(); } } /** * 检查图片的边界,防止图片的下标超出规定范围。 */ private void checkImageSwitchBorder(int action) { if (action == SCROLL_NEXT && ++mCurrentImage >= mCount) { mCurrentImage = 0; } else if (action == SCROLL_PREVIOUS && --mCurrentImage < 0) { mCurrentImage = mCount - 1; } } /** * 判断是否应该滚动到下一张图片。 */ private boolean shouldScrollToNext(int velocityX) { return velocityX < -SNAP_VELOCITY || getScrollX() > mImageWidth / 2; } /** * 判断是否应该滚动到上一张图片。 */ private boolean shouldScrollToPrevious(int velocityX) { return velocityX > SNAP_VELOCITY || getScrollX() < -mImageWidth / 2; } /** * 图片滚动的监听器 */ public interface OnImageSwitchListener { /** * 当图片滚动时会回调此方法 * * @param currentImage 当前图片的坐标 */ void onImageSwitch(int currentImage); } }
public class Image3DView extends ImageView { /** * 旋转角度的基准值 */ private static final float BASE_DEGREE = 50f; /** * 旋转深度的基准值 */ private static final float BASE_DEEP = 150f; private Camera mCamera; private Matrix mMaxtrix; private Bitmap mBitmap; /** * 当前图片对应的下标 */ private int mIndex; /** * 在前图片在X轴方向滚动的距离 */ private int mScrollX; /** * Image3DSwitchView控件的宽度 */ private int mLayoutWidth; /** * 当前图片的宽度 */ private int mWidth; /** * 当前旋转的角度 */ private float mRotateDegree; /** * 旋转的中心点 */ private float mDx; /** * 旋转的深度 */ private float mDeep; public Image3DView(Context context, AttributeSet attrs) { super(context, attrs); mCamera = new Camera(); mMaxtrix = new Matrix(); //设置可获焦 & 可点击 setFocusable(true); setClickable(true); } /** * 初始化Image3DView所需要的信息,包括图片宽度,截取背景图等。 */ public void initImageViewBitmap() { if (mBitmap == null) { //我们要获取cache首先要通过setDrawingCacheEnable方法开启cache,然后再调用getDrawingCache方法就可以获得view的cache图片了。 setDrawingCacheEnabled(true); buildDrawingCache(); mBitmap = getDrawingCache(); } mLayoutWidth = Image3DSwitchView.mWidth; mWidth = getWidth() + Image3DSwitchView.IMAGE_PADDING * 2; } /** * 设置旋转角度。 * * @param index 当前图片的下标 * @param scrollX 当前图片在X轴方向滚动的距离 */ public void setRotateData(int index, int scrollX) { mIndex = index; mScrollX = scrollX; } /** * 回收当前的Bitmap对象,以释放内存。 */ public void recycleBitmap() { if (mBitmap != null && !mBitmap.isRecycled()) { mBitmap.recycle(); } } @Override public void setImageResource(int resId) { super.setImageResource(resId); mBitmap = null; initImageViewBitmap(); } @Override public void setImageBitmap(Bitmap bm) { super.setImageBitmap(bm); mBitmap = null; initImageViewBitmap(); } @Override public void setImageDrawable(Drawable drawable) { super.setImageDrawable(drawable); mBitmap = null; initImageViewBitmap(); } @Override public void setImageURI(Uri uri) { super.setImageURI(uri); mBitmap = null; initImageViewBitmap(); } @Override protected void onDraw(Canvas canvas) { if (mBitmap == null) { // 如果Bitmap对象还不存在,先使用父类的onDraw方法进行绘制 super.onDraw(canvas); } else { if (isImageVisible()) { // 绘图时需要注意,只有当图片可见的时候才进行绘制,这样可以节省运算效率 computeRotateData(); mCamera.save(); mCamera.translate(0.0f, 0.0f, mDeep); mCamera.rotateY(mRotateDegree); mCamera.getMatrix(mMaxtrix); mCamera.restore(); mMaxtrix.preTranslate(-mDx, -getHeight() / 2); mMaxtrix.postTranslate(mDx, getHeight() / 2); canvas.drawBitmap(mBitmap, mMaxtrix, null); } } } /** * 在这里计算所有旋转所需要的数据。 */ private void computeRotateData() { float degreePerPix = BASE_DEGREE / mWidth; float deepPerPix = BASE_DEEP / ((mLayoutWidth - mWidth) / 2); switch (mIndex) { case 0: mDx = mWidth; mRotateDegree = 360f - (2 * mWidth + mScrollX) * degreePerPix; if (mScrollX < -mWidth) { mDeep = 0; } else { mDeep = (mWidth + mScrollX) * deepPerPix; } break; case 1: if (mScrollX > 0) { mDx = mWidth; mRotateDegree = (360f - BASE_DEGREE) - mScrollX * degreePerPix; mDeep = mScrollX * deepPerPix; } else { if (mScrollX < -mWidth) { mDx = -Image3DSwitchView.IMAGE_PADDING * 2; mRotateDegree = (-mScrollX - mWidth) * degreePerPix; } else { mDx = mWidth; mRotateDegree = 360f - (mWidth + mScrollX) * degreePerPix; } mDeep = 0; } break; case 2: if (mScrollX > 0) { mDx = mWidth; mRotateDegree = 360f - mScrollX * degreePerPix; mDeep = 0; if (mScrollX > mWidth) { mDeep = (mScrollX - mWidth) * deepPerPix; } } else { mDx = -Image3DSwitchView.IMAGE_PADDING * 2; mRotateDegree = -mScrollX * degreePerPix; mDeep = 0; if (mScrollX < -mWidth) { mDeep = -(mWidth + mScrollX) * deepPerPix; } } break; case 3: if (mScrollX < 0) { mDx = -Image3DSwitchView.IMAGE_PADDING * 2; mRotateDegree = BASE_DEGREE - mScrollX * degreePerPix; mDeep = -mScrollX * deepPerPix; } else { if (mScrollX > mWidth) { mDx = mWidth; mRotateDegree = 360f - (mScrollX - mWidth) * degreePerPix; } else { mDx = -Image3DSwitchView.IMAGE_PADDING * 2; mRotateDegree = BASE_DEGREE - mScrollX * degreePerPix; } mDeep = 0; } break; case 4: mDx = -Image3DSwitchView.IMAGE_PADDING * 2; mRotateDegree = (2 * mWidth - mScrollX) * degreePerPix; if (mScrollX > mWidth) { mDeep = 0; } else { mDeep = (mWidth - mScrollX) * deepPerPix; } break; } } /** * 判断当前图片是否可见。 * * @return 当前图片可见返回true,不可见返回false。 */ private boolean isImageVisible() { boolean isVisible = false; switch (mIndex) { case 0: if (mScrollX < (mLayoutWidth - mWidth) / 2 - mWidth) { isVisible = true; } else { isVisible = false; } break; case 1: if (mScrollX > (mLayoutWidth - mWidth) / 2) { isVisible = false; } else { isVisible = true; } break; case 2: if (mScrollX > mLayoutWidth / 2 + mWidth / 2 || mScrollX < -mLayoutWidth / 2 - mWidth / 2) { isVisible = false; } else { isVisible = true; } break; case 3: if (mScrollX < -(mLayoutWidth - mWidth) / 2) { isVisible = false; } else { isVisible = true; } break; case 4: if (mScrollX > mWidth - (mLayoutWidth - mWidth) / 2) { isVisible = true; } else { isVisible = false; } break; } return isVisible; } }
public class MainActivity extends AppCompatActivity { private Button btn; private Image3DSwitchView image3DSwitchView; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); btn = (Button) findViewById(R.id.btn); image3DSwitchView = (Image3DSwitchView) findViewById(R.id.image_switch_view); btn.setOnKeyListener(new View.OnKeyListener() { @Override public boolean onKey(View v, int keyCode, KeyEvent event) { if (keyCode == KeyEvent.KEYCODE_DPAD_UP && event.getAction()== KeyEvent.ACTION_DOWN) image3DSwitchView.requestFocus(); return true; } }); //设置监听,并实现接口 image3DSwitchView.setonFocusListener(new Image3DSwitchView.OnFocusListener() { @Override public void onFocus() { btn.requestFocus(); } @Override public void setValue(String value) { btn.setText(value+"/7"); } }); } }
4.自己的成长点:
①响应遥控器按键事件:重写Image3DSwitchView类的dispatchKeyEvent()函数
@Override public boolean dispatchKeyEvent(KeyEvent event) { if (event.getAction() == KeyEvent.ACTION_DOWN){ switch (event.getKeyCode()){ //按下键 响应回调 case KeyEvent.KEYCODE_DPAD_DOWN: if (onFocusListener != null){onFocusListener.onFocus();} break; //按确定键 case KeyEvent.KEYCODE_DPAD_CENTER: Toast.makeText(getContext(),"点击了图片"+(currentPage%7+1),Toast.LENGTH_SHORT).show(); break; //右键 case KeyEvent.KEYCODE_DPAD_RIGHT: scrollToNext(); if (onFocusListener !=null){ onFocusListener.setValue((currentPage%7+1)+""); } break; //左键 case KeyEvent.KEYCODE_DPAD_LEFT: scrollToPrevious(); if (onFocusListener !=null){ onFocusListener.setValue((currentPage%7+1)+""); } break; } } return true; }
注意:要能响应点击事件的前提必须是控件可以获得焦点,所以在构造函数中加上
setFocusable(true);
②回调机制:类似Android TV开发:使用RecycleView实现横向的Listview并响应点击事件的代码的原理。 越来越发现回调技术的好用:轻松通过接口函数里面的参数把动态变化的变量传递到mainActivity
public interface OnFocusListener{ void onFocus();//处理焦点 void setValue(String value);//处理当前页码 } private OnFocusListener onFocusListener; public void setonFocusListener(OnFocusListener onFocusListener){ this.onFocusListener = onFocusListener; www.jb51.net/article/140153.htm} @Override public boolean dispatchKeyEvent(KeyEvent event) { if (event.getAction() == KeyEvent.ACTION_DOWN){ switch (event.getKeyCode()){ //按下键 响应回调 case KeyEvent.KEYCODE_DPAD_DOWN: if (onFocusListener != null){onFocusListener.onFocus();} break; //按确定键 case KeyEvent.KEYCODE_DPAD_CENTER: Toast.makeText(getContext(),"点击了图片"+(currentPage%7+1),Toast.LENGTH_SHORT).show(); break; //右键 case KeyEvent.KEYCODE_DPAD_RIGHT: scrollToNext(); if (onFocusListener !=null){ onFocusListener.setValue((currentPage%7+1)+""); } break; //左键 case KeyEvent.KEYCODE_DPAD_LEFT: scrollToPrevious(); if (onFocusListener !=null){ onFocusListener.setValue((currentPage%7+1)+""); } break; } } return true; }
在acitivity中调用
image3DSwitchView.setonFocusListener(new Image3DSwitchView.OnFocusListener() { @Override public void onFocus() { btn.requestFocus();//让Image3DSwitchView控件下的按钮获得焦点 } @Override public void setValue(String value) { btn.setText(value+"/7");//给按钮设置 第几页/共几页 } });
5.源码+apk下载地址
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持脚本之家。