最近遇到一个特殊的需求，，需要一个超出屏幕大小的view，动态绘制中间的内容,开始时以为使用双重scrollview可以很简单的实现，但是发现，paint绘制错乱，滚动事件冲突，找了很久都没有完美符合的，只能参考大佬的自己魔改了一个双套件的组件了
1.此为里层
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.util.AttributeSet;
import android.util.Log;
import android.view.GestureDetector;
import android.view.Gravity;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.animation.AccelerateInterpolator;
import android.view.animation.DecelerateInterpolator;
import android.widget.LinearLayout;
import android.widget.OverScroller;
import androidx.annotation.Nullable;
import androidx.core.view.ViewCompat;
import com.rerise.reriselib.R;
import com.rerise.reriselib.utils.ScaleHelper;
import static android.view.ViewGroup.LayoutParams.WRAP_CONTENT;
public class ZoomLayout extends LinearLayout {
private static final String TAG = "ZoomLayout";
private static final float DEFAULT_MAX_ZOOM = 8.0F;
private static final float DEFAULT_MIN_ZOOM = 1.5F;
private static final float DEFAULT_DOUBLE_CLICK_ZOOM = 6.0f;
private float mDoubleClickZoom;
private float mMinZoom;
private float mMaxZoom;
private float mCurrentZoom = 1;
private int mMinimumVelocity;
private int mMaximumVelocity;
private boolean mScrollBegin; // 是否已经开始滑动
private ScaleGestureDetector mScaleDetector;
private GestureDetector mGestureDetector;
private OverScroller mOverScroller;
private ScaleHelper mScaleHelper;
private AccelerateInterpolator mAccelerateInterpolator;
private DecelerateInterpolator mDecelerateInterpolator;
private ZoomLayoutGestureListener mZoomLayoutGestureListener;
private int mLastChildHeight;
private int mLastChildWidth;
private int mLastHeight;
private int mLastWidth;
private int mLastCenterX;
private int mLastCenterY;
private boolean mNeedReScale;
private OnScaleListener onScaleListener;
public interface OnScaleListener {
void OnScale(float Scale);
}
public void setOnScaleListener(OnScaleListener onScaleListener) {
this.onScaleListener = onScaleListener;
}
public ZoomLayout(Context context) {
super(context);
init(context, null);
}
public ZoomLayout(Context context, AttributeSet attrs) {
super(context, attrs);
init(context, attrs);
}
public ZoomLayout(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init(context, attrs);
}
private void init(Context context, @Nullable AttributeSet attrs) {
mScaleDetector = new ScaleGestureDetector(context, mSimpleOnScaleGestureListener);
mGestureDetector = new GestureDetector(context, mSimpleOnGestureListener);
mOverScroller = new OverScroller(getContext());
mScaleHelper = new ScaleHelper();
final ViewConfiguration configuration = ViewConfiguration.get(getContext());
mMinimumVelocity = configuration.getScaledMinimumFlingVelocity();
mMaximumVelocity = configuration.getScaledMaximumFlingVelocity();
setWillNotDraw(false);
if (attrs != null) {
TypedArray array = null;
try {
array = context.obtainStyledAttributes(attrs, R.styleable.ZoomLayout);
mMinZoom = array.getFloat(R.styleable.ZoomLayout_min_zoom, DEFAULT_MIN_ZOOM);
mMaxZoom = array.getFloat(R.styleable.ZoomLayout_max_zoom, DEFAULT_MAX_ZOOM);
mDoubleClickZoom = array.getFloat(R.styleable.ZoomLayout_double_click_zoom, DEFAULT_DOUBLE_CLICK_ZOOM);
if (mDoubleClickZoom > mMaxZoom) {
mDoubleClickZoom = mMaxZoom;
}
} catch (Exception e) {
Log.e(TAG, TAG, e);
} finally {
if (array != null) {
array.recycle();
}
}
}
}
private ScaleGestureDetector.SimpleOnScaleGestureListener mSimpleOnScaleGestureListener = new ScaleGestureDetector.SimpleOnScaleGestureListener() {
@Override
public boolean onScale(ScaleGestureDetector detector) {
if (!isEnabled()) {
return false;
}
float newScale;
newScale = mCurrentZoom * detector.getScaleFactor();
if (newScale > mMaxZoom) {
newScale = mMaxZoom;
} else if (newScale < mMinZoom) {
newScale = mMinZoom;
}
setScale(newScale, (int) detector.getFocusX(), (int) detector.getFocusY());
return true;
}
@Override
public boolean onScaleBegin(ScaleGestureDetector detector) {
if (mZoomLayoutGestureListener != null) {
mZoomLayoutGestureListener.onScaleGestureBegin();
}
return true;
}
@Override
public void onScaleEnd(ScaleGestureDetector detector) {
}
};
private GestureDetector.SimpleOnGestureListener mSimpleOnGestureListener = new GestureDetector.SimpleOnGestureListener() {
@Override
public boolean onDown(MotionEvent e) {
if (!mOverScroller.isFinished()) {
mOverScroller.abortAnimation();
}
return true;
}
@Override
public boolean onDoubleTap(MotionEvent e) {
float newScale;
if (mCurrentZoom < 1) {
newScale = DEFAULT_MIN_ZOOM;
} else if (mCurrentZoom < mDoubleClickZoom) {
newScale = mDoubleClickZoom;
} else {
newScale = DEFAULT_MIN_ZOOM;
}
smoothScale(newScale, (int) e.getX(), (int) e.getY());
if (mZoomLayoutGestureListener != null) {
mZoomLayoutGestureListener.onDoubleTap();
}
return true;
}
@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
if (!isEnabled()) {
return false;
}
if (!mScrollBegin) {
mScrollBegin = true;
if (mZoomLayoutGestureListener != null) {
mZoomLayoutGestureListener.onScrollBegin();
}
}
processScroll((int) distanceX, (int) distanceY, getScrollRangeX(), getScrollRangeY());
return true;
}
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
if (!isEnabled()) {
return false;
}
fling((int) -velocityX, (int) -velocityY);
return true;
}
};
private boolean fling(int velocityX, int velocityY) {
if (Math.abs(velocityX) < mMinimumVelocity) {
velocityX = 0;
}
if (Math.abs(velocityY) < mMinimumVelocity) {
velocityY = 0;
}
final int scrollY = getScrollY();
final int scrollX = getScrollX();
final boolean canFlingX = (scrollX > 0 || velocityX > 0) &&
(scrollX < getScrollRangeX() || velocityX < 0);
final boolean canFlingY = (scrollY > 0 || velocityY > 0) &&
(scrollY < getScrollRangeY() || velocityY < 0);
boolean canFling = canFlingY || canFlingX;
if (canFling) {
velocityX = Math.max(-mMaximumVelocity, Math.min(velocityX, mMaximumVelocity));
velocityY = Math.max(-mMaximumVelocity, Math.min(velocityY, mMaximumVelocity));
int height = getHeight() - getPaddingBottom() - getPaddingTop();
int width = getWidth() - getPaddingRight() - getPaddingLeft();
int bottom = getContentHeight();
int right = getContentWidth();
mOverScroller.fling(getScrollX(), getScrollY(), velocityX, velocityY, 0, Math.max(0, right - width), 0,
Math.max(0, bottom - height), 0, 0);
notifyInvalidate();
return true;
}
return false;
}
public void smoothScale(float newScale, int centerX, int centerY) {
onScaleListener.OnScale(newScale);
if (mCurrentZoom > newScale) {
if (mAccelerateInterpolator == null) {
mAccelerateInterpolator = new AccelerateInterpolator();
}
mScaleHelper.startScale(mCurrentZoom, newScale, centerX, centerY, mAccelerateInterpolator);
} else {
if (mDecelerateInterpolator == null) {
mDecelerateInterpolator = new DecelerateInterpolator();
}
mScaleHelper.startScale(mCurrentZoom, newScale, centerX, centerY, mDecelerateInterpolator);
}
notifyInvalidate();
}
private void notifyInvalidate() {
// 效果和 invalidate 一样，但是会使得动画更平滑
ViewCompat.postInvalidateOnAnimation(this);
}
public void setScale(float scale, int centerX, int centerY) {
mLastCenterX = centerX;
mLastCenterY = centerY;
float preScale = mCurrentZoom;
mCurrentZoom = scale;
onScaleListener.OnScale(scale);
int sX = getScrollX();
int sY = getScrollY();
int dx = (int) ((sX + centerX) * (scale / preScale - 1));
int dy = (int) ((sY + centerY) * (scale / preScale - 1));
if (getScrollRangeX() < 0) {
child().setPivotX(child().getWidth() / 2);
child().setTranslationX(0);
} else {
child().setPivotX(0);
int willTranslateX = -(child().getLeft());
child().setTranslationX(willTranslateX);
}
if (getScrollRangeY() < 0) {
child().setPivotY(child().getHeight() / 2);
child().setTranslationY(0);
} else {
int willTranslateY = -(child().getTop());
child().setTranslationY(willTranslateY);
child().setPivotY(0);
}
child().setScaleX(mCurrentZoom);
child().setScaleY(mCurrentZoom);
processScroll(dx, dy, getScrollRangeX(), getScrollRangeY());
notifyInvalidate();
}
private void processScroll(int deltaX, int deltaY,
int scrollRangeX, int scrollRangeY) {
int oldScrollX = getScrollX();
int oldScrollY = getScrollY();
int newScrollX = oldScrollX + deltaX;
int newScrollY = oldScrollY + deltaY;
final int left = 0;
final int right = scrollRangeX;
final int top = 0;
final int bottom = scrollRangeY;
if (newScrollX > right) {
newScrollX = right;
} else if (newScrollX < left) {
newScrollX = left;
}
if (newScrollY > bottom) {
newScrollY = bottom;
} else if (newScrollY < top) {
newScrollY = top;
}
if (newScrollX < 0) {
newScrollX = 0;
}
if (newScrollY < 0) {
newScrollY = 0;
}
Log.e(TAG, "newScrollX = " + newScrollX + " ,newScrollY = " + newScrollY);
scrollTo(newScrollX, newScrollY);
}
private int getScrollRangeX() {
final int contentWidth = getWidth() - getPaddingRight() - getPaddingLeft();
return (getContentWidth() - contentWidth);
}
private int getContentWidth() {
return (int) (child().getWidth() * mCurrentZoom);
}
private int getScrollRangeY() {
final int contentHeight = getHeight() - getPaddingBottom() - getPaddingTop();
return getContentHeight() - contentHeight;
}
private int getContentHeight() {
return (int) (child().getHeight() * mCurrentZoom);
}
private View child() {
return getChildAt(0);
}
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
super.onLayout(changed, l, t, r, b);
if (mNeedReScale) {
// 需要重新刷新，因为宽高已经发生变化
setScale(mCurrentZoom, mLastCenterX, mLastCenterY);
mNeedReScale = false;
}
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
child().setClickable(true);
if (child().getHeight() < getHeight() || child().getWidth() < getWidth()) {
setGravity(Gravity.CENTER);
} else {
setGravity(Gravity.TOP);
}
if (mLastChildWidth != child().getWidth() || mLastChildHeight != child().getHeight() || mLastWidth != getWidth()
|| mLastHeight != getHeight()) {
// 宽高变化后，记录需要重新刷新，放在下次 onLayout 处理，避免 View 的一些配置：比如 getTop() 没有初始化好
// 下次放在 onLayout 处理的原因是 setGravity 会在 onLayout 确定完位置，这时候去 setScale 导致位置的变化就不会导致用户看到
// 闪一下的问题
mNeedReScale = true;
}
mLastChildWidth = child().getWidth();
mLastChildHeight = child().getHeight();
mLastWidth = child().getWidth();
mLastHeight = getHeight();
if (mNeedReScale) {
notifyInvalidate();
}
}
@Override
public void computeScroll() {
super.computeScroll();
if (mScaleHelper.computeScrollOffset()) {
setScale(mScaleHelper.getCurScale(), mScaleHelper.getStartX(), mScaleHelper.getStartY());
}
if (mOverScroller.computeScrollOffset()) {
int oldX = getScrollX();
int oldY = getScrollY();
int x = mOverScroller.getCurrX();
int y = mOverScroller.getCurrY();
if (oldX != x || oldY != y) {
final int rangeY = getScrollRangeY();
final int rangeX = getScrollRangeX();
processScroll(x - oldX, y - oldY, rangeX, rangeY);
}
if (!mOverScroller.isFinished()) {
notifyInvalidate();
}
}
}
@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
if (ev.getAction() == MotionEvent.ACTION_UP) {
// 最后一根手指抬起的时候，重置 mScrollBegin 为 false
mScrollBegin = false;
}
mGestureDetector.onTouchEvent(ev);
mScaleDetector.onTouchEvent(ev);
return super.dispatchTouchEvent(ev);
}
@Override
protected void measureChildWithMargins(View child, int parentWidthMeasureSpec, int widthUsed,
int parentHeightMeasureSpec, int heightUsed) {
final MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams();
final int childWidthMeasureSpec = getChildMeasureSpec(parentWidthMeasureSpec,
getPaddingLeft() + getPaddingRight() + lp.leftMargin + lp.rightMargin
+ widthUsed, lp.width);
final int usedTotal = getPaddingTop() + getPaddingBottom() + lp.topMargin + lp.bottomMargin +
heightUsed;
final int childHeightMeasureSpec;
if (lp.height == WRAP_CONTENT) {
childHeightMeasureSpec = MeasureSpec.makeMeasureSpec(
Math.max(0, MeasureSpec.getSize(parentHeightMeasureSpec) - usedTotal),
MeasureSpec.UNSPECIFIED);
} else {
childHeightMeasureSpec = getChildMeasureSpec(parentHeightMeasureSpec,
getPaddingTop() + getPaddingBottom() + lp.topMargin + lp.bottomMargin
+ heightUsed, lp.height);
}
child.measure(childWidthMeasureSpec, childHeightMeasureSpec);
}
/**
* 是否可以在水平方向上滚动
* 举例: ViewPager 通过这个方法判断子 View 是否可以水平滚动，从而解决滑动冲突
*/
@Override
public boolean canScrollHorizontally(int direction) {
if (direction > 0) {
return getScrollX() < getScrollRangeX();
} else {
return getScrollX() > 0 && getScrollRangeX() > 0;
}
}
/**
* 是否可以在竖直方向上滚动
* 举例: ViewPager 通过这个方法判断子 View 是否可以竖直滚动，从而解决滑动冲突
*/
@Override
public boolean canScrollVertically(int direction) {
if (direction > 0) {
return getScrollY() < getScrollRangeY();
} else {
return getScrollY() > 0 && getScrollRangeY() > 0;
}
}
public void setZoomLayoutGestureListener(ZoomLayoutGestureListener zoomLayoutGestureListener) {
mZoomLayoutGestureListener = zoomLayoutGestureListener;
}
public interface ZoomLayoutGestureListener {
void onScrollBegin();
void onScaleGestureBegin();
void onDoubleTap();
}
}
2、此为外层
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.util.AttributeSet;
import android.util.Log;
import android.view.GestureDetector;
import android.view.Gravity;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.animation.AccelerateInterpolator;
import android.view.animation.DecelerateInterpolator;
import android.widget.LinearLayout;
import android.widget.OverScroller;
import androidx.annotation.Nullable;
import androidx.core.view.ViewCompat;
import com.rerise.reriselib.R;
import com.rerise.reriselib.utils.ScaleHelper;
import static android.view.ViewGroup.LayoutParams.WRAP_CONTENT;
public class FeedLayout extends LinearLayout {
private static final String TAG = "ZoomLayout";
private float mDoubleClickZoom;
private float mMinZoom;
private float mMaxZoom;
private float mCurrentZoom = 1;
private int mMinimumVelocity;
private int mMaximumVelocity;
private boolean mScrollBegin; // 是否已经开始滑动
private ScaleGestureDetector mScaleDetector;
private GestureDetector mGestureDetector;
private OverScroller mOverScroller;
private ScaleHelper mScaleHelper;
private AccelerateInterpolator mAccelerateInterpolator;
private DecelerateInterpolator mDecelerateInterpolator;
private ZoomLayoutGestureListener mZoomLayoutGestureListener;
private int mLastChildHeight;
private int mLastChildWidth;
private int mLastHeight;
private int mLastWidth;
private int mLastCenterX;
private int mLastCenterY;
private boolean mNeedReScale;
public FeedLayout(Context context) {
super(context);
init(context, null);
}
public FeedLayout(Context context, AttributeSet attrs) {
super(context, attrs);
init(context, attrs);
}
public FeedLayout(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init(context, attrs);
}
private GestureDetector.SimpleOnGestureListener mSimpleOnGestureListener = new GestureDetector.SimpleOnGestureListener() {
@Override
public boolean onDown(MotionEvent e) {
if (!mOverScroller.isFinished()) {
mOverScroller.abortAnimation();
}
return false;
}
@Override
public boolean onDoubleTap(MotionEvent e) {
float newScale;
return false;
}
@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
if (!isEnabled()) {
return false;
}
if (!mScrollBegin) {
mScrollBegin = true;
if (mZoomLayoutGestureListener != null) {
mZoomLayoutGestureListener.onScrollBegin();
}
}
processScroll((int) distanceX, (int) distanceY, getScrollRangeX(), getScrollRangeY());
return false;
}
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
if (!isEnabled()) {
return false;
}
return false;
}
};
private void init(Context context, @Nullable AttributeSet attrs) {
mScaleDetector = new ScaleGestureDetector(context, mSimpleOnScaleGestureListener);
mGestureDetector = new GestureDetector(context, mSimpleOnGestureListener);
mOverScroller = new OverScroller(getContext());
mScaleHelper = new ScaleHelper();
final ViewConfiguration configuration = ViewConfiguration.get(getContext());
mMinimumVelocity = configuration.getScaledMinimumFlingVelocity();
mMaximumVelocity = configuration.getScaledMaximumFlingVelocity();
setWillNotDraw(false);
if (attrs != null) {
TypedArray array = null;
try {
array = context.obtainStyledAttributes(attrs, R.styleable.ZoomLayout);
mMinZoom = array.getFloat(R.styleable.ZoomLayout_min_zoom, 1);
mMaxZoom = array.getFloat(R.styleable.ZoomLayout_max_zoom, 1);
mDoubleClickZoom = array.getFloat(R.styleable.ZoomLayout_double_click_zoom, 1);
if (mDoubleClickZoom > mMaxZoom) {
mDoubleClickZoom = mMaxZoom;
}
} catch (Exception e) {
Log.e(TAG, TAG, e);
} finally {
if (array != null) {
array.recycle();
}
}
}
}
private ScaleGestureDetector.SimpleOnScaleGestureListener mSimpleOnScaleGestureListener = new ScaleGestureDetector.SimpleOnScaleGestureListener() {
@Override
public boolean onScale(ScaleGestureDetector detector) {return false;}
@Override
public boolean onScaleBegin(ScaleGestureDetector detector) {
if (mZoomLayoutGestureListener != null) {
mZoomLayoutGestureListener.onScaleGestureBegin();
}
return true;
}
@Override
public void onScaleEnd(ScaleGestureDetector detector) {
}
};
private void notifyInvalidate() {
// 效果和 invalidate 一样，但是会使得动画更平滑
ViewCompat.postInvalidateOnAnimation(this);
}
public void setScale(float scale, int centerX, int centerY) {
mLastCenterX = centerX;
mLastCenterY = centerY;
float preScale = mCurrentZoom;
mCurrentZoom = scale;
int sX = getScrollX();
int sY = getScrollY();
int dx = (int) ((sX + centerX) * (scale / preScale - 1));
int dy = (int) ((sY + centerY) * (scale / preScale - 1));
if (getScrollRangeX() < 0) {
child().setPivotX(child().getWidth() / 2);
child().setTranslationX(0);
} else {
child().setPivotX(0);
int willTranslateX = -(child().getLeft());
child().setTranslationX(willTranslateX);
}
if (getScrollRangeY() < 0) {
child().setPivotY(child().getHeight() / 2);
child().setTranslationY(0);
} else {
int willTranslateY = -(child().getTop());
child().setTranslationY(willTranslateY);
child().setPivotY(0);
}
child().setScaleX(mCurrentZoom);
child().setScaleY(mCurrentZoom);
processScroll(dx, dy, getScrollRangeX(), getScrollRangeY());
notifyInvalidate();
}
private void processScroll(int deltaX, int deltaY,
int scrollRangeX, int scrollRangeY) {
int oldScrollX = getScrollX();
int oldScrollY = getScrollY();
int newScrollX = oldScrollX + deltaX;
int newScrollY = oldScrollY + deltaY;
final int left = 0;
final int right = scrollRangeX;
final int top = 0;
final int bottom = scrollRangeY;
if (newScrollX > right) {
newScrollX = right;
} else if (newScrollX < left) {
newScrollX = left;
}
if (newScrollY > bottom) {
newScrollY = bottom;
} else if (newScrollY < top) {
newScrollY = top;
}
if (newScrollX < 0) {
newScrollX = 0;
}
if (newScrollY < 0) {
newScrollY = 0;
}
Log.e(TAG, "newScrollX = " + newScrollX + " ,newScrollY = " + newScrollY);
scrollTo(newScrollX, newScrollY);
}
private int getScrollRangeX() {
final int contentWidth = getWidth() - getPaddingRight() - getPaddingLeft();
return (getContentWidth() - contentWidth);
}
private int getContentWidth() {
return (int) (child().getWidth() * mCurrentZoom);
}
private int getScrollRangeY() {
final int contentHeight = getHeight() - getPaddingBottom() - getPaddingTop();
return getContentHeight() - contentHeight;
}
private int getContentHeight() {
return (int) (child().getHeight() * mCurrentZoom);
}
private View child() {
return getChildAt(0);
}
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
super.onLayout(changed, l, t, r, b);
if (mNeedReScale) {
// 需要重新刷新，因为宽高已经发生变化
setScale(mCurrentZoom, mLastCenterX, mLastCenterY);
mNeedReScale = false;
}
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
child().setClickable(true);
if (child().getHeight() < getHeight() || child().getWidth() < getWidth()) {
setGravity(Gravity.CENTER);
} else {
setGravity(Gravity.TOP);
}
if (mLastChildWidth != child().getWidth() || mLastChildHeight != child().getHeight() || mLastWidth != getWidth()
|| mLastHeight != getHeight()) {
// 宽高变化后，记录需要重新刷新，放在下次 onLayout 处理，避免 View 的一些配置：比如 getTop() 没有初始化好
// 下次放在 onLayout 处理的原因是 setGravity 会在 onLayout 确定完位置，这时候去 setScale 导致位置的变化就不会导致用户看到
// 闪一下的问题
mNeedReScale = true;
}
mLastChildWidth = child().getWidth();
mLastChildHeight = child().getHeight();
mLastWidth = child().getWidth();
mLastHeight = getHeight();
if (mNeedReScale) {
notifyInvalidate();
}
}
@Override
public void computeScroll() {
super.computeScroll();
if (mScaleHelper.computeScrollOffset()) {
setScale(mScaleHelper.getCurScale(), mScaleHelper.getStartX(), mScaleHelper.getStartY());
}
if (mOverScroller.computeScrollOffset()) {
int oldX = getScrollX();
int oldY = getScrollY();
int x = mOverScroller.getCurrX();
int y = mOverScroller.getCurrY();
if (oldX != x || oldY != y) {
final int rangeY = getScrollRangeY();
final int rangeX = getScrollRangeX();
processScroll(x - oldX, y - oldY, rangeX, rangeY);
}
if (!mOverScroller.isFinished()) {
notifyInvalidate();
}
}
}
@Override
public boolean dispatchTouchEvent(MotionEvent ev) {
if (ev.getAction() == MotionEvent.ACTION_UP) {
// 最后一根手指抬起的时候，重置 mScrollBegin 为 false
mScrollBegin = false;
}
mGestureDetector.onTouchEvent(ev);
mScaleDetector.onTouchEvent(ev);
return super.dispatchTouchEvent(ev);
}
@Override
protected void measureChildWithMargins(View child, int parentWidthMeasureSpec, int widthUsed,
int parentHeightMeasureSpec, int heightUsed) {
final MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams();
final int childWidthMeasureSpec = getChildMeasureSpec(parentWidthMeasureSpec,
getPaddingLeft() + getPaddingRight() + lp.leftMargin + lp.rightMargin
+ widthUsed, lp.width);
final int usedTotal = getPaddingTop() + getPaddingBottom() + lp.topMargin + lp.bottomMargin +
heightUsed;
final int childHeightMeasureSpec;
if (lp.height == WRAP_CONTENT) {
childHeightMeasureSpec = MeasureSpec.makeMeasureSpec(
Math.max(0, MeasureSpec.getSize(parentHeightMeasureSpec) - usedTotal),
MeasureSpec.UNSPECIFIED);
} else {
childHeightMeasureSpec = getChildMeasureSpec(parentHeightMeasureSpec,
getPaddingTop() + getPaddingBottom() + lp.topMargin + lp.bottomMargin
+ heightUsed, lp.height);
}
child.measure(childWidthMeasureSpec, childHeightMeasureSpec);
}
/**
* 是否可以在水平方向上滚动
* 举例: ViewPager 通过这个方法判断子 View 是否可以水平滚动，从而解决滑动冲突
*/
@Override
public boolean canScrollHorizontally(int direction) {
if (direction > 0) {
return getScrollX() < getScrollRangeX();
} else {
return getScrollX() > 0 && getScrollRangeX() > 0;
}
}
/**
* 是否可以在竖直方向上滚动
* 举例: ViewPager 通过这个方法判断子 View 是否可以竖直滚动，从而解决滑动冲突
*/
@Override
public boolean canScrollVertically(int direction) {
if (direction > 0) {
return getScrollY() < getScrollRangeY();
} else {
return getScrollY() > 0 && getScrollRangeY() > 0;
}
}
public void setZoomLayoutGestureListener(ZoomLayoutGestureListener zoomLayoutGestureListener) {
mZoomLayoutGestureListener = zoomLayoutGestureListener;
}
public interface ZoomLayoutGestureListener {
void onScrollBegin();
void onScaleGestureBegin();
void onDoubleTap();
}
}
使用：
<com.rerise.reriselib.view.FeedLayout
android:id="@+id/zoom1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:clipChildren="false">
<com.rerise.reriselib.view.ZoomLayout
android:id="@+id/zoom"
android:layout_width="2600px"
android:layout_height="2600px"
android:clipChildren="false">
<include layout="@layout/include_subline_map" />
</com.rerise.reriselib.view.ZoomLayout>
</com.rerise.reriselib.view.FeedLayout>
