我正在使用RotateAnimation，我想在动画运行时更改动画，例如，更改“toDegrees”参数，并使动画更短或更长。
感谢。
答案 0 :(得分：0)
您有cancel() startOffsetTime()和restrictDuration()。我没有看到任何改变学位的api，所以你可能不得不开始一个新的RotateAnitmation
答案 1 :(得分：0)
这可以帮助您（只需将getter和setter添加到所需的字段）
package com.test;
import android.content.Context;
import android.content.res.TypedArray;
import android.util.AttributeSet;
import android.view.animation.Animation;
import android.view.animation.Transformation;
/**
* An animation that controls the rotation of an object. This rotation takes
* place int the X-Y plane. You can specify the point to use for the center of
* the rotation, where (0,0) is the top left point. If not specified, (0,0) is
* the default rotation point.
*
*/
public class MyRotateAnimation extends Animation {
private float mFromDegrees;
private float mToDegrees;
private int mPivotXType = ABSOLUTE;
private int mPivotYType = ABSOLUTE;
private float mPivotXValue = 0.0f;
private float mPivotYValue = 0.0f;
private float mPivotX;
private float mPivotY;
/**
* Constructor used when a RotateAnimation is loaded from a resource.
*
* @param context Application context to use
* @param attrs Attribute set from which to read values
*/
public ZenRotateAnimation(Context context, AttributeSet attrs) {
super(context, attrs);
}
/**
* Constructor to use when building a RotateAnimation from code.
* Default pivotX/pivotY point is (0,0).
*
* @param fromDegrees Rotation offset to apply at the start of the
* animation.
*
* @param toDegrees Rotation offset to apply at the end of the animation.
*/
public MyRotateAnimation(float fromDegrees, float toDegrees) {
mFromDegrees = fromDegrees;
mToDegrees = toDegrees;
mPivotX = 0.0f;
mPivotY = 0.0f;
}
/**
* Constructor to use when building a RotateAnimation from code
*
* @param fromDegrees Rotation offset to apply at the start of the
* animation.
*
* @param toDegrees Rotation offset to apply at the end of the animation.
*
* @param pivotX The X coordinate of the point about which the object is
* being rotated, specified as an absolute number where 0 is the left
* edge.
* @param pivotY The Y coordinate of the point about which the object is
* being rotated, specified as an absolute number where 0 is the top
* edge.
*/
public MyRotateAnimation(float fromDegrees, float toDegrees, float pivotX, float pivotY) {
mFromDegrees = fromDegrees;
mToDegrees = toDegrees;
mPivotXType = ABSOLUTE;
mPivotYType = ABSOLUTE;
mPivotXValue = pivotX;
mPivotYValue = pivotY;
}
/**
* Constructor to use when building a RotateAnimation from code
*
* @param fromDegrees Rotation offset to apply at the start of the
* animation.
*
* @param toDegrees Rotation offset to apply at the end of the animation.
*
* @param pivotXType Specifies how pivotXValue should be interpreted. One of
* Animation.ABSOLUTE, Animation.RELATIVE_TO_SELF, or
* Animation.RELATIVE_TO_PARENT.
* @param pivotXValue The X coordinate of the point about which the object
* is being rotated, specified as an absolute number where 0 is the
* left edge. This value can either be an absolute number if
* pivotXType is ABSOLUTE, or a percentage (where 1.0 is 100%)
* otherwise.
* @param pivotYType Specifies how pivotYValue should be interpreted. One of
* Animation.ABSOLUTE, Animation.RELATIVE_TO_SELF, or
* Animation.RELATIVE_TO_PARENT.
* @param pivotYValue The Y coordinate of the point about which the object
* is being rotated, specified as an absolute number where 0 is the
* top edge. This value can either be an absolute number if
* pivotYType is ABSOLUTE, or a percentage (where 1.0 is 100%)
* otherwise.
*/
public MyRotateAnimation(float fromDegrees, float toDegrees, int pivotXType, float pivotXValue,
int pivotYType, float pivotYValue) {
mFromDegrees = fromDegrees;
mToDegrees = toDegrees;
mPivotXValue = pivotXValue;
mPivotXType = pivotXType;
mPivotYValue = pivotYValue;
mPivotYType = pivotYType;
}
@Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
float degrees = mFromDegrees + ((mToDegrees - mFromDegrees) * interpolatedTime);
if (mPivotX == 0.0f && mPivotY == 0.0f) {
t.getMatrix().setRotate(degrees);
} else {
t.getMatrix().setRotate(degrees, mPivotX, mPivotY);
}
}
@Override
public void initialize(int width, int height, int parentWidth, int parentHeight) {
super.initialize(width, height, parentWidth, parentHeight);
mPivotX = resolveSize(mPivotXType, mPivotXValue, width, parentWidth);
mPivotY = resolveSize(mPivotYType, mPivotYValue, height, parentHeight);
}
/**
* @return the mFromDegrees
*/
public synchronized float getmFromDegrees() {
return mFromDegrees;
}
/**
* @param mFromDegrees the mFromDegrees to set
*/
public synchronized void setmFromDegrees(float mFromDegrees) {
this.mFromDegrees = mFromDegrees;
}
/**
* @return the mToDegrees
*/
public synchronized float getmToDegrees() {
return mToDegrees;
}
/**
* @param mToDegrees the mToDegrees to set
*/
public synchronized void setmToDegrees(float mToDegrees) {
this.mToDegrees = mToDegrees;
}
/**
* @return the mPivotXType
*/
public synchronized int getmPivotXType() {
return mPivotXType;
}
/**
* @param mPivotXType the mPivotXType to set
*/
public synchronized void setmPivotXType(int mPivotXType) {
this.mPivotXType = mPivotXType;
}
/**
* @return the mPivotYType
*/
public synchronized int getmPivotYType() {
return mPivotYType;
}
/**
* @param mPivotYType the mPivotYType to set
*/
public synchronized void setmPivotYType(int mPivotYType) {
this.mPivotYType = mPivotYType;
}
/**
* @return the mPivotXValue
*/
public synchronized float getmPivotXValue() {
return mPivotXValue;
}
/**
* @param mPivotXValue the mPivotXValue to set
*/
public synchronized void setmPivotXValue(float mPivotXValue) {
this.mPivotXValue = mPivotXValue;
}
/**
* @return the mPivotYValue
*/
public synchronized float getmPivotYValue() {
return mPivotYValue;
}
/**
* @param mPivotYValue the mPivotYValue to set
*/
public synchronized void setmPivotYValue(float mPivotYValue) {
this.mPivotYValue = mPivotYValue;
}
/**
* @return the mPivotX
*/
public synchronized float getmPivotX() {
return mPivotX;
}
/**
* @param mPivotX the mPivotX to set
*/
public synchronized void setmPivotX(float mPivotX) {
this.mPivotX = mPivotX;
}
/**
* @return the mPivotY
*/
public synchronized float getmPivotY() {
return mPivotY;
}
/**
* @param mPivotY the mPivotY to set
*/
public synchronized void setmPivotY(float mPivotY) {
this.mPivotY = mPivotY;
}
}
答案 2 :(得分：0)
接受的答案对我不起作用。所需要的是“平滑”延续当前动画而不会出现故障。相反，我稍微修改了RotationAnimation类以返回“当前使用的”度，然后可以使用它：
/**
* Allows you to fetch the currently 'used' animation degrees so you can create a new animator
* out of it, allowing smooth animation
*/
class AdjustableRotationAnimation extends Animation {
private float mFromDegrees;
private float mToDegrees;
private volatile float mAnimatedDegrees;
private int mPivotXType = ABSOLUTE;
private int mPivotYType = ABSOLUTE;
private float mPivotXValue = 0.0f;
private float mPivotYValue = 0.0f;
private float mPivotX;
private float mPivotY;
public AdjustableRotationAnimation(Context context, AttributeSet attrs) {
super(context, attrs);
}
public AdjustableRotationAnimation(float fromDegrees, float toDegrees) {
mFromDegrees = fromDegrees;
mToDegrees = toDegrees;
mPivotX = 0.0f;
mPivotY = 0.0f;
}
public AdjustableRotationAnimation(float fromDegrees, float toDegrees, float pivotX, float pivotY) {
mFromDegrees = fromDegrees;
mToDegrees = toDegrees;
mPivotXType = ABSOLUTE;
mPivotYType = ABSOLUTE;
mPivotXValue = pivotX;
mPivotYValue = pivotY;
}
public AdjustableRotationAnimation(float fromDegrees, float toDegrees, int pivotXType, float pivotXValue,
int pivotYType, float pivotYValue) {
mFromDegrees = fromDegrees;
mToDegrees = toDegrees;
mPivotXValue = pivotXValue;
mPivotXType = pivotXType;
mPivotYValue = pivotYValue;
mPivotYType = pivotYType;
}
@Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
mAnimatedDegrees = mFromDegrees + ((mToDegrees - mFromDegrees) * interpolatedTime);
float scale = getScaleFactor();
if (mPivotX == 0.0f && mPivotY == 0.0f) {
t.getMatrix().setRotate(mAnimatedDegrees);
} else {
t.getMatrix().setRotate(mAnimatedDegrees, mPivotX * scale, mPivotY * scale);
}
}
@Override
public void initialize(int width, int height, int parentWidth, int parentHeight) {
super.initialize(width, height, parentWidth, parentHeight);
mPivotX = resolveSize(mPivotXType, mPivotXValue, width, parentWidth);
mPivotY = resolveSize(mPivotYType, mPivotYValue, height, parentHeight);
}
public synchronized float getAnimatedDegrees() {
return mAnimatedDegrees;
}
}
这就是我使用它的方式：
currentRotate = currentRotate % DEGREES_360;
int animationDuration = 400;
if (rotateAnimation != null && !rotateAnimation.hasEnded()) {
rotateAnimation = new AdjustableRotationAnimation(rotateAnimation.getAnimatedDegrees(), currentRotate, Animation.RELATIVE_TO_SELF, CENTER, Animation.RELATIVE_TO_SELF, CENTER);
rotateAnimation.setInterpolator(new DecelerateInterpolator());
rotateAnimation.setDuration(animationDuration);
rotateAnimation.setFillAfter(true);
rotateAnimation.setAnimationListener(this);
} else {
rotateAnimation = new AdjustableRotationAnimation(lastRotation, currentRotate, Animation.RELATIVE_TO_SELF, CENTER, Animation.RELATIVE_TO_SELF, CENTER);
rotateAnimation.setInterpolator(new DecelerateInterpolator());
rotateAnimation.setDuration(animationDuration);
rotateAnimation.setFillAfter(true);
rotateAnimation.setAnimationListener(this);
}
viewToRotate.startAnimation(rotateAnimation);
每次都会创建一个新的动画，但它会给人一种延续的感觉，动画将从“取消”的地方顺利地继续。