需要做一个动画（在Android 2.2及以上）：
1.Moving从上到下按钮（点击之后他），
从底部2.Moving回顶部（再次点击他后）。
第一个动画工作正常，但第二个不是，BTN“跳跃”，从底部到顶部，而不是动画。
码：
public class MainActivity extends Activity {
static RelativeLayout relativeLayout;
static Button btn;
static Boolean isUp = true;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn = (Button) findViewById(R.id.button1);
relativeLayout = (RelativeLayout) findViewById(R.id.relative_layout);
btn.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
if(isUp){
isUp = false;
v.startAnimation(MainActivity.getVerticalSlideAnimation(0,relativeLayout.getBottom() - v.getHeight(),500,0));
}else{
isUp = true;
v.startAnimation(MainActivity.getVerticalSlideAnimation(relativeLayout.getBottom() - v.getHeight(),0,500,0));
}
}
});
}
public static Animation getVerticalSlideAnimation(int fromYPosition, final int toYPosition, int duration, int startOffset)
{
TranslateAnimation translateAnimation = new TranslateAnimation(1, 0.0F, 1, 0.0F, 0, fromYPosition, 0, toYPosition);
translateAnimation.setDuration(duration);
translateAnimation.setInterpolator(new AccelerateInterpolator());
translateAnimation.setStartOffset(startOffset);
//Stop animation after finishing.
//translateAnimation.setFillAfter(true);
translateAnimation.setAnimationListener(new AnimationListener()
{
public void onAnimationStart(Animation animation) { }
public void onAnimationRepeat(Animation animation) { }
public void onAnimationEnd(Animation animation) {
btn.setY(toYPosition);
}
});
return translateAnimation;
}
}
布局：
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/relative_layout"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:text="Button" />
</RelativeLayout>
好吧，我解决了这个问题。
还有，你应该知道动画几个issuses：
动画paremeters都不是简单的“从（固定位置）” - >“将（固定位置）”你应该想到。 还有很多类似的“从（当前位置/ 0）” - >“多少步骤要做，哪个方向（PLUSE正/负负）”
动画不改变屏幕上的视图的实际位置，因此，如果你想停在终点位置的动画，你应该使用：
animation.setFillAfter(true);
如果你想改变视图的实际位置，你应该更新视图参数对“onAnimationEnd”（如下面的代码），或计算位置（在“onAnimationEnd”再次）手动设置Y / X位置，如：
animatedView.setY(stopPosition);
编码：
public class AnimationActivity extends Activity {
private boolean isUp;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
((Button) findViewById(R.id.button1))
.setOnClickListener(new OnClickListener() {
public void onClick(final View v) {
final float direction = (isUp) ? -1 : 1;
final float yDelta = getScreenHeight() - (2 * v.getHeight());
final int layoutTopOrBottomRule = (isUp) ? RelativeLayout.ALIGN_PARENT_TOP : RelativeLayout.ALIGN_PARENT_BOTTOM;
final Animation animation = new TranslateAnimation(0,0,0, yDelta * direction);
animation.setDuration(500);
animation.setAnimationListener(new AnimationListener() {
public void onAnimationStart(Animation animation) {
}
public void onAnimationRepeat(Animation animation) {
}
public void onAnimationEnd(Animation animation) {
// fix flicking
// Source : http://stackoverflow.com/questions/9387711/android-animation-flicker
TranslateAnimation anim = new TranslateAnimation(0.0f, 0.0f, 0.0f, 0.0f);
anim.setDuration(1);
v.startAnimation(anim);
//set new params
LayoutParams params = new LayoutParams(v.getLayoutParams());
params.addRule(RelativeLayout.CENTER_HORIZONTAL);
params.addRule(layoutTopOrBottomRule);
v.setLayoutParams(params);
}
});
v.startAnimation(animation);
//reverse direction
isUp = !isUp;
}
});
}
private float getScreenHeight() {
DisplayMetrics displaymetrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);
return (float) displaymetrics.heightPixels;
}
}
public class AnimationActivity extends Activity {
private boolean isUp;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
((Button) findViewById(R.id.button1))
.setOnClickListener(new OnClickListener() {
public void onClick(final View v) {
final float direction = (isUp) ? -1 : 1;
final float yDelta = getScreenHeight() - (2 * v.getHeight());
final int layoutTopOrBottomRule = (isUp) ? RelativeLayout.ALIGN_PARENT_TOP : RelativeLayout.ALIGN_PARENT_BOTTOM;
final Animation animation = new TranslateAnimation(0,0,0, yDelta * direction);
animation.setDuration(500);
animation.setAnimationListener(new AnimationListener() {
public void onAnimationStart(Animation animation) {
}
public void onAnimationRepeat(Animation animation) {
}
public void onAnimationEnd(Animation animation) {
// fix flicking
// Source : http://stackoverflow.com/questions/9387711/android-animation-flicker
TranslateAnimation anim = new TranslateAnimation(0.0f, 0.0f, 0.0f, 0.0f);
anim.setDuration(1);
v.startAnimation(anim);
//set new params
LayoutParams params = new LayoutParams(v.getLayoutParams());
params.addRule(RelativeLayout.CENTER_HORIZONTAL);
params.addRule(layoutTopOrBottomRule);
v.setLayoutParams(params);
}
});
v.startAnimation(animation);
//reverse direction
isUp = !isUp;
}
});
}
private float getScreenHeight() {
DisplayMetrics displaymetrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(displaymetrics);
return (float) displaymetrics.heightPixels;
}
