我有一个活动,需要定期更换ImageView,因此我编写了以下代码。
imageview.setImageUri(resId);
我正在增加资源ID。虽然它运行良好,但一个图像会突然转换为另一个。我不想要那样,我希望图像视图的过渡是平稳的。我该怎么做?
我有一个活动,需要定期更换ImageView,因此我编写了以下代码。
imageview.setImageUri(resId);
我正在增加资源ID。虽然它运行良好,但一个图像会突然转换为另一个。我不想要那样,我希望图像视图的过渡是平稳的。我该怎么做?
试试这个
ImageView demoImage = (ImageView) findViewById(R.id.DemoImage);
int imagesToShow[] = { R.drawable.image1, R.drawable.image2,R.drawable.image3 };
animate(demoImage, imagesToShow, 0,false);
private void animate(final ImageView imageView, final int images[], final int imageIndex, final boolean forever) {
//imageView <-- The View which displays the images
//images[] <-- Holds R references to the images to display
//imageIndex <-- index of the first image to show in images[]
//forever <-- If equals true then after the last image it starts all over again with the first image resulting in an infinite loop. You have been warned.
int fadeInDuration = 500; // Configure time values here
int timeBetween = 3000;
int fadeOutDuration = 1000;
imageView.setVisibility(View.INVISIBLE); //Visible or invisible by default - this will apply when the animation ends
imageView.setImageResource(images[imageIndex]);
Animation fadeIn = new AlphaAnimation(0, 1);
fadeIn.setInterpolator(new DecelerateInterpolator()); // add this
fadeIn.setDuration(fadeInDuration);
Animation fadeOut = new AlphaAnimation(1, 0);
fadeOut.setInterpolator(new AccelerateInterpolator()); // and this
fadeOut.setStartOffset(fadeInDuration + timeBetween);
fadeOut.setDuration(fadeOutDuration);
AnimationSet animation = new AnimationSet(false); // change to false
animation.addAnimation(fadeIn);
animation.addAnimation(fadeOut);
animation.setRepeatCount(1);
imageView.setAnimation(animation);
animation.setAnimationListener(new AnimationListener() {
public void onAnimationEnd(Animation animation) {
if (images.length - 1 > imageIndex) {
animate(imageView, images, imageIndex + 1,forever); //Calls itself until it gets to the end of the array
}
else {
if (forever == true){
animate(imageView, images, 0,forever); //Calls itself to start the animation all over again in a loop if forever = true
}
}
}
public void onAnimationRepeat(Animation animation) {
// TODO Auto-generated method stub
}
public void onAnimationStart(Animation animation) {
// TODO Auto-generated method stub
}
});
}
尝试使用alpha动画。首先淡出ImageView,在动画结束时更改资源,然后淡入ImageView。
animate(imageView, images, imageIndex % images.length + 1,forever);
这样索引将始终在范围内。 - Miquel Perez