假设我有一个垂直线性布局:
[v1]
[v2]
默认情况下，v1已经可见= GONE。我想用一个展开动画显示v1，同时下推v2。
我是这样做的:
Animation a = new Animation()
{
int initialHeight;
@Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
final int newHeight = (int)(initialHeight * interpolatedTime);
v.getLayoutParams().height = newHeight;
v.requestLayout();
}
@Override
public void initialize(int width, int height, int parentWidth, int parentHeight) {
super.initialize(width, height, parentWidth, parentHeight);
initialHeight = height;
}
@Override
public boolean willChangeBounds() {
return true;
}
};
但是用这个解决方案，当动画开始时我有一个眨眼。我认为这是由于v1在应用动画之前显示全尺寸。
用javascript，这是一行jQuery!android有什么简单的方法吗?
这是一个片段，我用来调整一个视图(线性布局)的宽度与动画。
代码应该根据目标大小进行扩展或收缩。如果你想要一个fill_parent宽度，你必须在将标志设置为true时将父类. getmeasuredwidth作为目标宽度。
希望它能帮助到你们中的一些人。
public class WidthResizeAnimation extends Animation {
int targetWidth;
int originaltWidth;
View view;
boolean expand;
int newWidth = 0;
boolean fillParent;
public WidthResizeAnimation(View view, int targetWidth, boolean fillParent) {
this.view = view;
this.originaltWidth = this.view.getMeasuredWidth();
this.targetWidth = targetWidth;
newWidth = originaltWidth;
if (originaltWidth > targetWidth) {
expand = false;
} else {
expand = true;
}
this.fillParent = fillParent;
}
@Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
if (expand && newWidth < targetWidth) {
newWidth = (int) (newWidth + (targetWidth - newWidth) * interpolatedTime);
}
if (!expand && newWidth > targetWidth) {
newWidth = (int) (newWidth - (newWidth - targetWidth) * interpolatedTime);
}
if (fillParent && interpolatedTime == 1.0) {
view.getLayoutParams().width = -1;
} else {
view.getLayoutParams().width = newWidth;
}
view.requestLayout();
}
@Override
public void initialize(int width, int height, int parentWidth, int parentHeight) {
super.initialize(width, height, parentWidth, parentHeight);
}
@Override
public boolean willChangeBounds() {
return true;
}
}
这是非常简单的droidQuery。首先，考虑这样的布局:
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical" >
<LinearLayout
android:id="@+id/v1"
android:layout_width="wrap_content"
android:layout_height="wrap_content" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="View 1" />
</LinearLayout>
<LinearLayout
android:id="@+id/v2"
android:layout_width="wrap_content"
android:layout_height="0dp" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="View 2" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="View 3" />
</LinearLayout>
</LinearLayout>
我们可以使用下面的代码将高度动画到所需的值-比如100dp:
//convert 100dp to pixel value
int height = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 100, getResources().getDisplayMetrics());
然后使用droidQuery进行动画。最简单的方法是:
$.animate("{ height: " + height + "}", new AnimationOptions());
为了让动画更吸引人，可以考虑添加一个easing:
$.animate("{ height: " + height + "}", new AnimationOptions().easing($.Easing.BOUNCE));
你也可以使用duration()方法改变AnimationOptions上的持续时间，或者处理动画结束时发生的事情。对于一个复杂的例子，试试:
$.animate("{ height: " + height + "}", new AnimationOptions().easing($.Easing.BOUNCE)
.duration(1000)
.complete(new Function() {
@Override
public void invoke($ d, Object... args) {
$.toast(context, "finished", Toast.LENGTH_SHORT);
}
}));
这是我的解决方案。我认为这样更简单。它只是扩展了视图，但很容易扩展。
public class WidthExpandAnimation extends Animation
{
int _targetWidth;
View _view;
public WidthExpandAnimation(View view)
{
_view = view;
}
@Override
protected void applyTransformation(float interpolatedTime, Transformation t)
{
if (interpolatedTime < 1.f)
{
int newWidth = (int) (_targetWidth * interpolatedTime);
_view.layout(_view.getLeft(), _view.getTop(),
_view.getLeft() + newWidth, _view.getBottom());
}
else
_view.requestLayout();
}
@Override
public void initialize(int width, int height, int parentWidth, int parentHeight)
{
super.initialize(width, height, parentWidth, parentHeight);
_targetWidth = width;
}
@Override
public boolean willChangeBounds() {
return true;
}
}
好吧，我刚刚发现了一个非常丑陋的解决方案:
public static Animation expand(final View v, Runnable onEnd) {
try {
Method m = v.getClass().getDeclaredMethod("onMeasure", int.class, int.class);
m.setAccessible(true);
m.invoke(
v,
MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED),
MeasureSpec.makeMeasureSpec(((View)v.getParent()).getMeasuredHeight(), MeasureSpec.AT_MOST)
);
} catch (Exception e){
Log.e("test", "", e);
}
final int initialHeight = v.getMeasuredHeight();
Log.d("test", "initialHeight="+initialHeight);
v.getLayoutParams().height = 0;
v.setVisibility(View.VISIBLE);
Animation a = new Animation()
{
@Override
protected void applyTransformation(float interpolatedTime, Transformation t) {
final int newHeight = (int)(initialHeight * interpolatedTime);
v.getLayoutParams().height = newHeight;
v.requestLayout();
}
@Override
public boolean willChangeBounds() {
return true;
}
};
a.setDuration(5000);
v.startAnimation(a);
return a;
}
请随意提出一个更好的解决方案!
展开/折叠视图的最佳解决方案:
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
View view = buttonView.getId() == R.id.tb_search ? fSearch : layoutSettings;
transform(view, 200, isChecked
? ViewGroup.LayoutParams.WRAP_CONTENT
: 0);
}
public static void transform(final View v, int duration, int targetHeight) {
int prevHeight = v.getHeight();
v.setVisibility(View.VISIBLE);
ValueAnimator animator;
if (targetHeight == ViewGroup.LayoutParams.WRAP_CONTENT) {
v.measure(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
animator = ValueAnimator.ofInt(prevHeight, v.getMeasuredHeight());
} else {
animator = ValueAnimator.ofInt(prevHeight, targetHeight);
}
animator.addUpdateListener(animation -> {
v.getLayoutParams().height = (animation.getAnimatedFraction() == 1.0f)
? targetHeight
: (int) animation.getAnimatedValue();
v.requestLayout();
});
animator.setInterpolator(new LinearInterpolator());
animator.setDuration(duration);
animator.start();
}
